09/27/2021 | Press release | Distributed by Public on 09/27/2021 15:29

Supplemental Prospectus (SEC Filing - 424B5)

ktra-424b5.htm

Filed Pursuant to Rule 424(b)(5)

Registration No. 333-254662

PROSPECTUS SUPPLEMENT

(To Prospectus dated April 1, 2021)

Kintara Therapeutics, Inc.

7,200,000 Shares of Common Stock

Pre-Funded Warrants to Purchase up to 4,800,000 Shares of Common Stock

Warrants to Purchase up to 12,000,000 Shares of Common Stock

Placement Agent Warrants to Purchase up to 600,000 Shares of Common Stock

Shares of Common Stock underlying the Pre-Funded Warrants, Warrants and Placement Agent Warrants

We are offering 7,200,000 shares of our common stock, par value $0.001 per share, and warrants to purchase up to 12,000,000 shares of common stock. Each share of common stock is being sold together with one warrant to purchase one share of common stock. Each warrant will have an exercise price of $1.25 per share, will be immediately exercisable and will expire on the three and a half year anniversary of the original issuance date. This offering also relates to the shares of common stock issuable upon exercise of the warrants sold in this offering The shares of common stock and the warrants are immediately separable and will be issued separately, but will be purchased together in this offering.

We are also offering pre-funded warrants to purchase up to an aggregate of 4,800,000 shares of common stock to certain institutional investors whose purchase of shares of common stock in this offering would otherwise result in such purchasers, together with their affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchasers, 9.99%) of our outstanding shares of common stock immediately following the closing of this offering. Subject to limited exceptions, a holder of pre-funded warrants will not have the right to exercise any portion of its pre-funded warrants if the holder, together with its affiliates, would beneficially own in excess of 4.99% (or, at the election of the holder, 9.99%) of the number of shares of common stock outstanding immediately after giving effect to such exercise. Each pre-funded warrant to purchase one share of common stock is being sold together with one warrant to purchase one share of common stock. This offering also relates to the shares of common stock issuable upon exercise of any pre-funded warrants sold in this offering. Each pre-funded warrant and accompanying warrant is being sold at a price of $1.249. Each pre-funded warrant will have an exercise price per share of common stock equal to $0.001 and is exercisable at any time after its original issuance until exercised in full. The shares of common stock and the warrants are immediately separable and will be issued separately, but will be purchased together in this offering. The shares of common stock, pre-funded warrants and warrants are being sold directly to certain institutional investors pursuant to this prospectus supplement and the accompanying prospectus and a securities purchase agreement dated September 23, 2021.

Our shares of common stock are listed on The Nasdaq Capital Market LLC ("Nasdaq") under the symbol "KTRA". There is no established trading market for the pre-funded warrants. the warrants or the placement agent warrants, and we do not expect a market to develop. We do not intend to apply for a listing for any such warrants on any securities exchange or other nationally recognized trading system. Without an active trading market, the liquidity of the pre-funded warrants, the warrants, or the placement agent warrants will be limited. On September 24, 2021, the last reported sales price of our common stock on Nasdaq was $0.88 per share.

We have retained H.C. Wainwright & Co., LLC to act as our exclusive placement agent in connection with the securities offered by this prospectus supplement and the accompanying prospectus. The placement agent has no obligation to buy any of the securities from us or to arrange for the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay the placement agent the placement agent fees set forth in the table below, which assumes that we sell all of the securities we are offering.

Investing in our securities involves risks. Before buying any securities, you should read the discussion of material risks of investing in our common stock in "Risk Factors" beginning on page S-7 of this prospectus supplement, on page 4 of the accompanying prospectus and in the documents incorporated by reference in this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

Delivery of the shares of our common stock, pre-funded warrants, warrants, and placement agent warrants being offered pursuant to this prospectus supplement and the accompanying prospectus is expected to be made on or about September 28, 2021, subject to satisfaction of customary closing conditions.

H.C. Wainwright & Co.

The date of this prospectus supplement is September 23, 2021.

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

PROSPECTUS

i

ABOUT THIS PROSPECTUS SUPPLEMENT

On March 24, 2021, we filed with the Securities and Exchange Commission, or SEC, a registration statement on Form S-3 (File No. 333-254662) utilizing a "shelf" registration process relating to the securities described in this prospectus supplement, which registration statement was declared effective on April 1, 2021. Under this shelf registration process, we may offer and sell, either individually or in combination, in one or more offerings, any of the securities described in the accompanying prospectus, for total gross proceeds of up to $100,000,000.

This prospectus supplement describes the specific terms of this offering and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein and into the accompanying prospectus. The second part, the accompanying prospectus, provides more general information. If the information in this prospectus supplement or any relevant free writing prospectus we may authorize for use in connection with this offering is inconsistent with the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement or such free writing prospectus, you should rely on the information in this prospectus supplement or such free writing prospectus.

We and the placement agent have not authorized anyone to provide you with any information or to make any representations other than those included or incorporated by reference in this prospectus supplement and the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering. If you receive any information not authorized by us, we and the placement agent take no responsibility for, and can provide no assurance as to the reliability of, such information. We are not making an offer to sell the securities offered hereby in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained or incorporated by reference in this prospectus supplement or the accompanying prospectus or any relevant free writing prospectus we may authorize for use in connection with this offering is accurate as of any date other than its respective date, regardless of its time of delivery or any sale of the securities covered hereby. Our business, financial condition, results of operations and prospects may have changed since that date.

It is important for you to read and consider all of the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering in making your investment decision. This prospectus supplement contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. We include cross-references in this prospectus supplement and the accompanying prospectus to captions in these materials where you can find additional related discussions. The table of contents in this prospectus supplement provides the pages on which these captions are located. You should read both this prospectus supplement and the accompanying prospectus, together with the additional information described in the sections entitled "Where You Can Find Additional Information" on page S-19 and "Incorporation of Certain Information by Reference" on page S-20 of this prospectus supplement, before investing in our common stock.

We are offering to sell, and seeking offers to buy, the securities offered hereby only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement, the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering and the offering of the securities offered hereby in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement, the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering must inform themselves about, and observe any restrictions relating to, the offering of the securities offered hereby and the distribution of this prospectus supplement, the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering outside the United States. This prospectus supplement, the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement, the accompanying prospectus and any relevant free writing prospectus we may authorize for use in connection with this offering by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

Kintara Therapeutics, Inc. and its consolidated subsidiaries are referred to herein as "Kintara," "the Company," "we," "us" and "our," unless the context indicates otherwise.

This prospectus supplement and the accompanying prospectus contain, or incorporate by reference, trademarks, tradenames, service marks and service names of Kintara Therapeutics, Inc. and its subsidiaries.

S-2

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, including the documents that we incorporate by reference, contains forward-looking statements as that term is defined in the federal securities laws. The events described in forward-looking statements contained in this prospectus supplement, including the documents that we incorporate by reference, may not occur. Generally, these statements relate to our business plans or strategies, projected or anticipated benefits or other consequences of our plans or strategies, financing plans, projected or anticipated benefits from acquisitions that we may make, or projections involving anticipated revenues, earnings or other aspects of our operating results or financial position, and the outcome of any contingencies. Any such forward-looking statements are based on current expectations, estimates and projections of management. We intend for these forward-looking statements to be covered by the safe-harbor provisions for forward-looking statements. Words such as "may," "expect," "believe," "anticipate," "project," "plan," "intend," "estimate," and "continue," and their opposites and similar expressions are intended to identify forward-looking statements. We caution you that these statements are not guarantees of future performance or events and are subject to a number of uncertainties, risks and other influences, many of which are beyond our control that may influence the accuracy of the statements and the projections upon which the statements are based. Factors that may affect our results include, but are not limited to, the risks and uncertainties discussed in the "Risk Factors" section on page S-7 of this prospectus supplement and on page 4 of the accompanying prospectus, in our Annual Report on Form 10-K for the fiscal year ended June 30, 2020 or in other reports we file with the Securities and Exchange Commission.

Any one or more of these uncertainties, risks and other influences could materially affect our results of operations and whether forward-looking statements made by us ultimately prove to be accurate. Our actual results, performance and achievements could differ materially from those expressed or implied in these forward-looking statements. We undertake no obligation to publicly update or revise any forward-looking statements, whether from new information, future events or otherwise.

You should rely only on the information in this prospectus supplement and accompanying base prospectus. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it.

S-3

PROSPECTUS SUPPLEMENT SUMMARY

The following summary highlights some information from this prospectus supplement. It is not complete and does not contain all of the information that you should consider before making an investment decision. You should read this entire prospectus, including the "Risk Factors" section on page S-7 and the accompanying prospectus on page 2, the consolidated financial statements and related notes and the other more detailed information appearing elsewhere or incorporated by reference into this prospectus supplement.

The Company

We are a clinical stage, biopharmaceutical company focused on the development and commercialization of new cancer therapies. We are dedicated to the development of novel cancer therapies for patients with unmet medical needs. Our mission is to benefit patients by developing and commercializing anti-cancer therapies for patients whose solid tumors exhibit features that make them resistant to, or unlikely to respond to, currently available therapies, with particular focus on orphan cancer indications.

Our two lead candidates are VAL-083, a novel, validated, DNA-targeting agent, for the treatment of drug-resistant solid tumors such as glioblastoma multiforme ("GBM") and potentially other solid tumors, including ovarian cancer, non-small cell lung cancer ("NSCLC"), and diffuse intrinsic pontine glioma ("DIPG") and REM-001, a late-stage photodynamic therapy ("PDT") for the treatment of cutaneous metastatic breast cancer ("CMBC"). PDT is a treatment that uses light sensitive compounds, or photosensitizers, that, when exposed to specific wavelengths of light, act as a catalyst to produce a form of oxygen that induces local tumor cell death.

Corporate Information

Our address is 12707 High Bluff Dr., Suite 200, San Diego, CA 92130 and our telephone number is (858) 350-4364. Our corporate website is: www.kintara.com. Our website and the information contained on, or that can be accessed through, our website shall not be deemed to be incorporated by reference in, and are not considered part of, this prospectus supplement. You should not rely on any such information in making your decision whether to purchase our common stock.

S-4

THE OFFERING

S-5

The number of shares of our common stock to be outstanding immediately after this offering is based on 35,974,989 shares outstanding as of September 24, 2021, and excludes, as of that date, the following:

S-6

RISK FACTORS

Before deciding whether to invest in our securities, you should carefully consider the risk factors set forth below and incorporated by reference in this prospectus supplement from our Annual Report on Form 10-K for the fiscal year ended June 30, 2020 and any subsequent updates described in our Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as the risks, uncertainties and additional information set forth in our SEC reports on Forms 10-K, 10-Q and 8-K and in the other documents incorporated by reference in this prospectus supplement. For a description of these reports and documents, and information about where you can find them, see "Where You Can Find Additional Information" and "Incorporation of Certain Information By Reference". Additional risks not presently known or that we presently consider to be immaterial could subsequently materially and adversely affect our financial condition, results of operations, business and prospects.

Risks Related to this Offering and our Common Stock

This is a best efforts offering, no minimum number or dollar amount of securities is required to be sold, and we may not raise the amount of capital we believe is required for our business plans.

The placement agent has agreed to use its reasonable best efforts to solicit offers to purchase the securities in this offering. The placement agent has no obligation to buy any of the securities from us or to arrange for the purchase or sale of any specific number or dollar amount of the securities. There is no required minimum number of securities that must be sold as a condition to completion of this offering. Because there is no minimum offering amount required as a condition to the closing of this offering, the actual offering amount, placement agent fees and proceeds to us are not presently determinable and may be substantially less than the maximum amounts set forth above. We may sell fewer than all of the securities offered hereby, which may significantly reduce the amount of proceeds received by us, and investors in this offering will not receive a refund in the event that we do not sell an amount of securities sufficient to fund our expected capital needs. Thus, we may not raise the amount of capital we believe is required for our operations and may need to raise additional funds, which may not be available or available on terms acceptable to us.

We have broad discretion in the use of the net proceeds from this offering and our existing cash and may not use them effectively.

Our management will have broad discretion in the application of the net proceeds from this offering, including for any of the purposes described in the section entitled "Use of Proceeds," as well as our existing cash and cash equivalents, and you will be relying on the judgment of our management regarding such application. You will not have the opportunity, as part of your investment decision, to assess whether the net proceeds are being used appropriately. Because of the number and variability of factors that will determine our use of the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. Our management might not apply the net proceeds or our existing cash in ways that ultimately increase the value of your investment. If we do not invest or apply the net proceeds from this offering or our existing cash and cash equivalents in ways that enhance stockholder value, we may fail to achieve expected business and financial results, which could cause our stock price to decline. Pending their use, we may invest the net proceeds from this offering in short-term, investment-grade, interest-bearing securities. These investments may not yield a favorable return to our stockholders.

You will experience immediate dilution in the book value per share of the securities you purchase in this offering.

Because the price per share of our common stock being offered is substantially higher than the pro forma net tangible book value per share of our common stock after giving effect to this offering, you will suffer substantial dilution in the pro forma as adjusted net tangible book value of the common stock you purchase in this offering. If you purchase shares of common stock in this offering, you will suffer immediate and substantial dilution of $0.57 per share in the pro forma as adjusted net tangible book value of the common stock you purchase. Any exercise of outstanding stock options, warrants or other equity awards will result in further dilution. See "Dilution" for a more detailed discussion of the dilution you will incur if you purchase our securities in this offering.

S-7

The issuance or sale of shares in the future to raise money or for strategic purposes could reduce the market price of our common stock.

In the future, we may issue securities to raise cash for operations, to pay down then existing indebtedness, as consideration for the acquisition of assets, as consideration for receipt of goods or services, and to pay for the development of our product candidates. We have and in the future may issue securities convertible into our common stock. Any of these events may dilute stockholders' ownership interests in our company and have an adverse impact on the price of our common stock.

In addition, sales of a substantial amount of our common stock in the public market, or the perception that these sales may occur, could reduce the market price of our common stock. This could also impair our ability to raise additional capital through the sale of our securities.

Any actual or anticipated sales of shares by our stockholders may cause the trading price of our common stock to decline. The sale of a substantial number of shares of our common stock by our stockholders, or anticipation of such sales, could make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise wish to effect sales.

Issuance of our common stock upon exercise of convertible securities may depress the price of our common stock.

Upon consummation of this offering, we will have 47,974,989 shares of common stock issued and outstanding, warrants to purchase 19,151,752 shares of common stock at a weighted-average exercise price of $1.99 per share (including warrants to purchase 12,000,000 shares of common stock to be issued in this offering and placement agent warrants to purchase 600,000 shares of common stock to be issued in this offering), 15,827,521 shares of common stock issuable upon conversion of Series C Stock, warrants to purchase 2,443 shares of Series C Stock at a weighted-average exercise price of $1,000 per share, and options to purchase 6,809,125 shares of common stock at a weighted-average exercise price of $2.16 per share. All warrants and stock options are convertible, or exercisable into, one share of common stock. The issuance of shares of our common stock upon the exercise of outstanding convertible securities could result in substantial dilution to our stockholders, which may have a negative effect on the price of our common stock.

There is no public market for the warrants and pre-funded warrants being offered by us in this offering.

There is no established public trading market for the warrants and the pre-funded warrants, and we do not expect a market to develop. In addition, we do not intend to apply to list the warrants or the pre-funded warrants on any national securities exchange or other nationally recognized trading system. Without an active market, the liquidity of the warrants and the pre-funded warrants will be limited.

Holders of the warrants offered hereby will have no rights as shareholders with respect to shares of common stock underlying the warrants until such holders exercise their warrants and acquire our common shares, except as otherwise provided in the warrants.

Until holders of the warrants and the pre-funded warrants acquire our shares of common stock upon exercise thereof, such holders will have no rights with respect to the shares of common stock underlying such warrants, except to the extent that holders of such warrants will have certain rights to participate in distributions or dividends paid on our shares of common stock as set forth in the warrants. Upon exercise of the warrants and the pre-funded warrants, the holders will be entitled to exercise the rights of a shareholder only as to matters for which the record date occurs after the exercise date.

S-8

USE OF PROCEEDS

We estimate that the net proceeds from the offering will be approximately $13.6 million, after deducting the placement agent fees and commissions and estimated offering expenses payable by us and excluding the proceeds, if any, from the subsequent exercise of the pre-funded warrants, warrants or placement agent warrants offered and issued pursuant to this offering. We cannot predict when or if the pre-funded warrants. warrants or placement agent warrants will be exercised. It is possible that the warrants may expire and may never be exercised.

We intend to use the net proceeds from the offering for working capital and other general corporate purposes, which may include funding acquisitions or investments in businesses, products or technologies that are complementary to our own. The amounts and timing of these expenditures will depend on numerous factors, including the development of our current business initiatives. We have no specific acquisition contemplated at this time. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds from this offering. The amounts and timing of our actual expenditures will depend on numerous factors, including factors described under "Risk Factors" in this prospectus supplement, the accompanying base prospectus and the documents incorporated by reference herein and therein.

S-9

DILUTION

The net tangible book value of our common stock as of March 31, 2021 was approximately $16.1million, or approximately $0.51per share of common stock. Net tangible book value per share represents the amount of our total tangible assets less total liabilities divided by the total number of our shares of common stock outstanding as of March 31, 2021.

After giving effect to the sale by us in this offering of 7,200,000 shares of common stock at a price per share and related warrant of $1.25 and pre-funded warrants to purchase 4,800,000 shares of common stock in this offering at a price of $1.249, assuming the exercise in full of the pre-funded warrants at the exercise price of $0.001 per share of common stock, and after deducting estimated placement agent fees and commissions and estimated offering expenses payable by us, our pro forma as adjusted net tangible book value as of March 31, 2021 would have been approximately $29.7 million, or approximately $0.68 per share of common stock. This represents an immediate increase in as adjusted net tangible book value of approximately $0.17 per share of common stock to our existing security holders and an immediate dilution in pro forma as adjusted net tangible book value of approximately $0.57 per share of common stock to purchasers of common stock in this offering, as illustrated by the following table:

The figures above are based on 31,764,223shares outstanding as of March 31, 2021 and excludes as of such date:

To the extent that outstanding exercisable options, pre-funded warrants, warrants or placement agent warrants are exercised, you may experience further dilution. In addition, we may need to raise additional capital and to the extent that we raise additional capital by issuing equity or convertible debt securities your ownership will be further diluted.

S-10

DESCRIPTION OF THE SECURITIES WE ARE OFFERING

In this offering, we are offering shares of our common stock, pre-funded warrants to purchase shares of common stock, warrants to purchase shares of common stock and placement warrants to purchase shares of common stock (and the shares of common stock issuable from time to time upon exercise of the warrants,pre-funded warrants and placement agent warrants). No fractional warrants will be issued.

Common Stock

Thematerial terms and provisions of our common stock and each other class of our securities that qualifies or limits our common stock are described under the caption "Description of Capital Stock" starting on page 5 of the accompanying prospectus. Our common stock is listed on the Nasdaq Global Market under the symbol "NOVN." Our transfer agent is American Stock Transfer & Trust Company, LLC.

Pre-Funded Warrants

The following is a summary of the material terms and provisions of the pre-funded warrants that are being offered hereby. This summary is subject to and qualified in its entirety by the form of pre-funded warrants, which has been provided to the investors in this offering and which will be filed with the SEC as an exhibit to a Current Report on Form 8-K in connection with this offering and incorporated by reference into the registration statement of which this prospectus supplement forms a part. Prospective investors should carefully review the terms and provisions of the form of pre-funded warrant for a complete description of the terms and conditions of the pre-funded warrants.

Duration and Exercise Price

The pre-funded warrants offered hereby will have an exercise price of $0.001 per share. The pre-funded warrants will be immediately exercisable and may be exercised at any time after their original issuance until such pre-funded warrants are exercised in full. The exercise price and number of shares of common stock issuable upon exercise are subject to appropriate adjustment in the event of share dividends, share splits, reorganizations or similar events affecting our shares of common stock. Pre-funded warrants will be issued in certificated form only.

Exercisability

The pre-funded warrants will be exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares of common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of such holder's warrants to the extent that the holder would own more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding shares of common stock immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of ownership of outstanding shares of common stock after exercising the holder's pre-funded warrants up to 9.99% of the number of shares of common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. Purchasers in this offering may also elect prior to the issuance of pre-funded warrants to have the initial exercise limitation set at 9.99% of our outstanding shares of common stock.

Cashless Exercise

If, at the time a holder exercises its pre-funded warrants, a registration statement registering the issuance of the shares of common stock underlying the pre-funded warrants under the Securities Act of 1933, as amended, or the Securities Act, is not then effective or available for the issuance of such shares, then in lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the net number of shares of common stock determined according to a formula set forth in the pre-funded warrant.

S-11

Fundamental Transactions

In the event of any fundamental transaction, as described in the pre-funded warrants and generally including any merger with or into another entity, sale of all or substantially all of our assets, tender offer or exchange offer, or reclassification of our shares of common stock, then upon any subsequent exercise of a pre-funded warrant, the holder will have the right to receive as alternative consideration, for each share of common stock that would have been issuable upon such exercise immediately prior to the occurrence of such fundamental transaction, the number of shares of common stock of the successor or acquiring corporation or of our company, if it is the surviving corporation, and any additional consideration receivable upon or as a result of such transaction by a holder of the number of shares of common stock for which the pre-funded warrant is exercisable immediately prior to such event.

Transferability

In accordance with its terms and subject to applicable laws, a pre-funded warrant may be transferred at the option of the holder upon surrender of the pre-funded warrant to us together with the appropriate instruments of transfer and payment of funds sufficient to pay any transfer taxes (if applicable).

Fractional Shares

No fractional shares of common stock will be issued upon the exercise of the pre-funded warrants. Rather, the number of shares of common stock to be issued will, at our election, either be rounded up to the nearest whole number or we will pay a cash adjustment in respect of such final fraction in an amount equal to such fraction multiplied by the exercise price.

Trading Market

There is no established trading market for the pre-funded warrants, and we do not expect a market to develop. We do not intend to apply for a listing for the pre-funded warrants on any securities exchange or other nationally recognized trading system. Without an active trading market, the liquidity of the pre-funded warrants will be limited.

Rights as a Shareholder

Except as otherwise provided in the pre-funded warrants or by virtue of the holders' ownership of shares of common stock, the holders of pre-funded warrants do not have the rights or privileges of holders of our shares of common stock, including any voting rights, until such pre-funded warrant holders exercise their warrants.

Warrants

The following summary of certain terms and provisions of the warrants that are being offered hereby is not complete and is subject to, and qualified in its entirety by, the provisions of the warrants, the form of which will be filed as an exhibit to a Current Report on Form 8-K that we will file with the SEC and that will be incorporated by reference into the registration statement of which this prospectus supplement forms a part. Prospective investors should carefully review the terms and provisions of the form of warrant for a complete description of the terms and conditions of the warrants.

Exercise Price and Duration

The warrants will have an exercise price of $1.25 per share. The warrants are exercisable immediately upon issuance, and at any time thereafter up to the three and a half year anniversary of the issuance date. The exercise price is subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our shares of common stock and also upon any distributions of assets, including cash, stock or other property to our shareholders.

S-12

Exercisability

The warrants will be exercisable, at the option of each holder, in whole or in part by delivering to us a duly executed exercise notice and, at any time a registration statement registering the issuance of the shares of common stock underlying the warrants under the Securities Act is effective and available for the issuance of such shares, or an exemption from registration under the Securities Act is available for the issuance of such shares, by payment in full in immediately available funds for the number of common shares purchased upon such exercise.

Cashless Exercise

If, at the time of exercise there is no effective registration statement registering, or the prospectus contained therein is not available for the issuance of, the shares of common stock underlying the warrants, then the warrants may also be exercised, in whole or in part, at such time by means of a cashless exercise, in which case the holder would receive upon such exercise the net number of common shares determined according to the formula set forth in the warrant.

Exercise Limitation

A holder will not have the right to exercise any portion of the warrant if the holder (together with its affiliates) would beneficially own in excess of 4.99% (or 9.99% upon the request of the holder) of the number of common shares outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the warrants. However, any holder may increase or decrease such percentage, provided that any increase will not be effective until the 61st day after such election.

Transferability

Subject to applicable laws, the warrants may be offered for sale, sold, transferred or assigned without our consent.

Fractional Shares

No fractional common shares will be issued upon the exercise of the warrants. Rather, the number of common shares to be issued will be rounded to the nearest whole number.

Trading Market

There is no established public trading market for the warrants being issued in this offering, and we do not expect a market to develop. We do not intend to apply for listing of the warrants on any securities exchange or other nationally recognized trading system. Without an active trading market, the liquidity of the warrants will be limited.

Fundamental Transactions

If a fundamental transaction occurs, then the successor entity will succeed to, and be substituted for us, and may exercise every right and power that we may exercise and will assume all of our obligations under the warrants with the same effect as if such successor entity had been named in the warrant itself. If holders of our common shares are given a choice as to the securities, cash or property to be received in a fundamental transaction, then the holder shall be given the same choice as to the consideration it receives upon any exercise of the warrant following such fundamental transaction.

Rights as a Shareholder

Except as otherwise provided in the warrants or by virtue of such holder's ownership of our shares of common stock, the holder of a warrant does not have the rights or privileges of a holder of our common shares, including any voting rights, until the holder exercises the warrant.

S-13

Amendment and Waiver

The warrants may be modified or amended or the provisions thereof waived with the written consent of our company and the respective holder.

Placement Agent Warrants

We have also agreed to issue to the placement agent the placement agent warrants to purchase up to 600,000 shares of common stock. The placement agent warrants will be exercisable immediately and will have substantially the same terms as the warrants described above, except that the placement agent warrants will have an exercise price of $1.565 per share (representing 125% of the public offering price). Reference is hereby made to the "-Warrants" description above and to the provisions of the placement agent warrant, which has been provided to the investors in this offering and will be filed with the SEC as an exhibit to a Current Report on Form 8-K in connection with this offering and incorporated by reference into the registration statement of which this prospectus supplement forms a part. Prospective investors should carefully review the terms and provisions of the form of warrant for a complete description of the terms and conditions of the warrants.

Other Warrants

Assuming full exercise of the pre-funded warrants and excluding the warrants and placement agent warrants to be issued as part of this offering, as of September 24, 2021, we had 6,551,752 shares of common stock issuable upon the exercise of outstanding warrants with a weighted average exercise price of approximately $3.38 per share and 2,100,302 shares of common stock issuable upon conversion of Series C Stock underlying warrants with an exercise conversion price of approximately $1.16 per share.

S-14

PLAN OF DISTRIBUTION

Pursuant to an engagement letter agreement dated September 10, 2021, we have engaged H.C. Wainwright & Co., LLC, referred to herein as Wainwright or the placement agent, to act as our exclusive placement agent in connection with this offering of our shares of common stock, pre-funded warrants and warrants pursuant to this prospectus supplement and accompanying prospectus. Under the terms of the engagement letter, the placement agent has agreed to be our exclusive placement agent, on a reasonable best efforts basis, in connection with the issuance and sale by us of our securities in this takedown from our shelf registration statement. The terms of this offering were subject to market conditions and negotiations between us, the placement agent and prospective investors. The engagement letter does not give rise to any commitment by the placement agent to purchase any of our shares of common stock, and the placement agent will have no authority to bind us by virtue of the engagement letter. Further, the placement agent does not guarantee that it will be able to raise new capital in any prospective offering. The placement agent may engage sub-agents or selected dealers to assist with the offering.

The placement agent proposes to arrange for the sale of the securities we are offering pursuant to this prospectus supplement and accompanying prospectus to one or more institutional or accredited investors through securities purchase agreements directly between the purchasers and us. We will only sell to such investors who have entered into the securities purchase agreement with us.

We will deliver the shares of common stock being issued to the investors electronically upon receipt of investor funds for the purchase of the shares of our common stock offered pursuant to this prospectus supplement. We expect to deliver the shares of our common stock, pre-funded warrants and warrants being offered pursuant to this prospectus supplement on or about September 28, 2021.

Commission and Expenses

The following table shows the per share and total placement agent fees we will pay in connection with the sale of the shares in this offering, reflecting the purchase of all of the securities we are offering.

We have agreed to pay the placement agent a total cash fee equal to 7.0% of the gross proceeds of this offering. We will also pay the placement agent $25,000 for non-accountable expenses, an expense allowance of $90,000 for legal fees and other out-of-pocket expenses and $15,950 for clearing fees. We estimate the total expenses payable by us for this offering will be approximately $1.4 million, which amount includes the placement agent's fees and reimbursable expenses.

In addition, we have agreed to issue to the placement agent warrants to purchase up to 5% of the aggregate number of shares of common stock or pre-funded warrants sold in this offering, or 600,000 shares. The placement agent warrants will have an exercise price equal to $1.5625, or 125% of the offering price per share (or pre-funded warrant) and warrant and will be exercisable for three and a half years from the effective date of this offering. The placement agent warrants and the shares of common stock issuable upon exercise thereof are being registered hereby.

S-15

Right of First Refusal

We have granted the placement agent a six-month right of first refusal to act as sole book-running manager, sole underwriter, or sole placement agent if we or any of our subsidiaries raise funds resulting in an aggregate gross proceeds to us of at least $15.0 million by means of a public offering (including at-the-market facility) or a private placement or any other capital-raising financing of equity, equity-linked or debt securities using an underwriter or placement agent. Such period will be extended to a twelve-month right of first refusal if one or more offerings during the term of engagement results in aggregate gross proceeds to us of at least $25.0 million.

If the placement agent or an affiliate of the placement agent accepts any such engagement, the agreement governing such engagement will contain, among other things, provisions for customary fees and terms for transactions of similar size and nature, including indemnification, which are appropriate to such a transaction.

Tail

We shall pay the placement agent the cash and warrant compensation provided above on the gross proceeds provided to us by investors that were brought over-the-wall or introduced to the Company by the placement agent during our engagement of the placement agent in a public or private offering or other financing or capital-raising transaction within six months following the termination of our engagement of the placement agent. This period will be extended to twelve months if one or more offerings during the term of engagement results in aggregate gross proceeds to the Company of at least $25.0 million.

Lock-Up Agreements

Each of our officers and directors have agreed to not sell any shares of our common stock or any securities convertible into or exercisable or exchangeable into share of common stock, subject to certain exceptions, for a period of 90 days after the closing of this offering. We have also agreed to a lock-up provision that prevents us from issuing any shares of common stock or any securities convertible into or exercisable or exchangeable into shares of common stock for a period of 75 days after the closing date of the offering.

The exceptions to the restriction with respect to the Company include, among other things, the issuance of any shares of our capital stock or securities convertible into shares of our capital stock that are issued (i) pursuant to a stock or option plan, (ii) pursuant to the exercise or exchange of or conversion of any securities exercisable or exchangeable for or convertible into shares of common stock issued and outstanding on the date of this prospectus supplement, (iii) as consideration in an acquisition, merger or similar strategic transaction approved by a majority of the disinterested directors, provided that such securities are issued as "restricted securities" as defined in Rule 144 and carry no registration rights that require or permit the filing of any registration statement in connection therewith within 90 days following the closing of this offering, and provided that any such issuance shall only be to a person providing us business synergies and additional benefits in addition to the investment of funds, but shall not include a transaction in which we are issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities.

Indemnification

We have agreed to indemnify the placement agent against certain liabilities, including civil liabilities under the Securities Act, or to contribute to payments that the placement agent may be required to make in respect of those liabilities.

Transfer Agent

The transfer agent and registrar for our common stock is Mountain Share Transfer, Inc. The transfer agent address is 2030 Powers Ferry Road SE, Suite #212, Atlanta, GA 30339, (404)-474-3110.

S-16

Listing

Our common stock is listed on Nasdaq under the symbol "KTRA". There is no established public trading market for the warrants or the pre-funded warrants, and we do not expect a market to develop. We do not intend to apply for listing of the warrants or the pre-funded warrants on any securities exchange or other nationally recognized trading system. Without an active trading market, the liquidity of the warrants, the pre-funded warrants and the warrants will be limited.

Regulation M The placement agent may be deemed to be an underwriter within the meaning of Section 2(a)(11) of the Securities Act, and any commissions received by it and any profit realized on the resale of the securities sold by it while acting as principal might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, the placement agent would be required to comply with the requirements of the Securities Act and the Exchange Act, including, without limitation, Rule 415(a)(4) under the Securities Act and Rule 10b-5 and Regulation M under the Exchange Act. These rules and regulations may limit the timing of purchases and sales of shares of common stock and warrants by the placement agent acting as principal. Under these rules and regulations, the placement agent:

From time to time, the placement agent has provided and may provide in the future various advisory, investment and commercial banking and other services to us, including acting as a financial advisor in connection with any business combination or strategic alternative, for which they have received and may continue to receive customary fees and commissions.

S-17

LEGAL MATTERS

The validity of the common stock being offered will be passed upon for us by Fennemore Craig, P.C., Reno, Nevada. Lowenstein Sandler, LLP, New York, New York, will pass upon certain legal matters relating to the issuance and sale of the common stock offered hereby. Ellenoff Grossman & Schole LLP is counsel for the placement agent in connection with this offering.

EXPERTS

The consolidated balance sheet of Kintara Therapeutics, Inc. as of June 30, 2020, and the related consolidated statements of operations, stockholders' equity and cash flows for the year then ended, have been audited by Marcum LLP, an independent registered public accounting firm, as stated in their report which is incorporated herein by reference. Such consolidated financial statements have been incorporated herein by reference in reliance on the report of such firm given upon their authority as experts in accounting and auditing.

The consolidated financial statements of Kintara Therapeutics, Inc. at June 30, 2019, and for the year then ended, appearing in Kintara Therapeutics, Inc.'s Annual Report (Form 10-K) for the year ended June 30, 2020, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

S-18

WHERE YOU CAN FIND ADDITIONAL INFORMATION

This prospectus supplement is part of a registration statement on Form S-3 that we have filed with the SEC relating to the shares of our securities being offered hereby. This prospectus supplement does not contain all of the information in the registration statement and its exhibits. The registration statement, its exhibits and the documents incorporated by reference in this prospectus supplement and their exhibits, all contain information that is material to the offering of the securities hereby. Whenever a reference is made in this prospectus supplement to any of our contracts or other documents, the reference may not be complete. You should refer to the exhibits that are a part of the registration statement in order to review a copy of the contract or documents. The registration statement and the exhibits are available at the SEC's Public Reference Room or through its website.

We file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC maintains an Internet site at http://www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers, such as us, that file electronically with the SEC. Additionally, you may access our filings with the SEC through our website at www.kintara.com. We have included our website address as an inactive textual reference only and our website and the information contained on, or that can be accessed through, our website will not be deemed to be incorporated by reference in, and are not considered part of, this prospectus supplement.

We will provide you without charge, upon your oral or written request, with an electronic or paper copy of any or all reports, proxy statements and other documents we file with the SEC, as well as any or all of the documents incorporated by reference in this prospectus supplement (other than exhibits to such documents unless such exhibits are specifically incorporated by reference into such documents). Requests for such copies should be directed to:

Kintara Therapeutics, Inc.

Attn: Saiid Zarrabian, Chief Executive Officer

12707 High Bluff Dr., Suite 200

San Diego, CA 92130

(858) 350-4364

You should rely only on the information in this prospectus supplement and the additional information described above and under the heading "Incorporation of Certain Information by Reference" below. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it. We are not making an offer to sell these securities in any jurisdiction where such offer or sale is not permitted. You should assume that the information in this prospectus supplement was accurate on the date of the front cover of this prospectus supplement only. Our business, financial condition, results of operations and prospects may have changed since that date.

S-19

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to "incorporate by reference" information that we file with it into this prospectus supplement, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus supplement. The information incorporated by reference is considered to be a part of this prospectus supplement, and information that we file later with the SEC will automatically update and supersede information contained in this prospectus supplement.

We incorporate by reference the documents listed below that we have previously filed with the SEC:

All reports and other documents (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed in such forms that are related to such items unless such Form 8-K expressly provides to the contrary) we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, prior to the termination of this offering, will also be incorporated by reference in this prospectus supplement and deemed to be part of this prospectus supplement from the date of the filing of such reports and documents.

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus supplement shall be deemed modified, superseded or replaced for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement, or in any subsequently filed document that also is deemed to be incorporated by reference in this prospectus supplement, modifies, supersedes or replaces such statement. Any statement so modified, superseded or replaced shall not be deemed, except as so modified, superseded or replaced, to constitute a part of this prospectus supplement. None of the information that we disclose under Items 2.02 or 7.01 of any Current Report on Form 8-K or any corresponding information, either furnished under Item 9.01 or included as an exhibit therein, that we may from time to time furnish to the SEC will be incorporated by reference into, or otherwise included in, this prospectus supplement, except as otherwise expressly set forth in the relevant document. Subject to the foregoing, all information appearing in this prospectus supplement is qualified in its entirety by the information appearing in the documents incorporated by reference.

S-20

PROSPECTUS

Kintara Therapeutics, Inc.

$100,000,000

Common Stock

Preferred Stock

Warrants

Debt Securities

Subscription Rights

Units

We may offer, issue and sell from time to time together or separately, in one or more offerings, any combination of (i) our common stock, (ii) our preferred stock, which we may issue in one or more series, (iii) warrants, (iv) senior or subordinated debt securities, (v) subscription rights and (vi) units. The debt securities may consist of debentures, notes, or other types of debt. The debt securities, preferred stock, warrants and subscription rights may be convertible into, or exercisable or exchangeable for, common or preferred stock or other securities of ours. The units may consist of any combination of the securities listed above.

The aggregate public offering price of the securities that we may offer will not exceed $100,000,000. We will offer the securities in an amount and on terms that market conditions will determine at the time of the offering. Our common stock is listed on the Nasdaq Capital Market under the symbol "KTRA." The last reported sale price for our common stock on March 23, 2021 as quoted on the Nasdaq Capital Market was $1.95 per share. You are urged to obtain current market quotations of our common stock. We have no preferred stock, warrants, debt securities, subscription rights or units listed on any market. Each prospectus supplement will indicate if the securities offered thereby will be listed on any securities exchange.

Investing in our securities involves risk. You should carefully consider the risks that we refer you to under the section captioned "Risk Factors" in this prospectus on page 3 before buying our securities.

Should we offer any of the securities described in this prospectus, we will provide you with the specific terms of the particular securities being offered in supplements to this prospectus. You should read this prospectus and any supplement, together with additional information described under the headings "Additional Information" and "Incorporation of Certain Information by Reference" carefully before you invest. This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

We may sell these securities directly to our stockholders or to other purchasers or through agents on our behalf or through underwriters or dealers as designated from time to time. If any agents or underwriters are involved in the sale of any of these securities, the applicable prospectus supplement will provide the names of the agents or underwriters and any applicable fees, commissions or discounts.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is April 1, 2021.

TABLE OF CONTENTS

Kintara Therapeutics, Inc. and its consolidated subsidiaries are referred to herein as "Kintara," "the Company," "we," "us" and "our," unless the context indicates otherwise.

You may only rely on the information contained in this prospectus and the accompanying prospectus supplement or that we have referred you to. We have not authorized anyone to provide you with different information. This prospectus and any prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities other than the securities offered by this prospectus and the prospectus supplement. This prospectus and any prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities in any circumstances in which such offer or solicitation is unlawful. Neither the delivery of this prospectus or any prospectus supplement nor any sale made hereunder shall, under any circumstances, create any implication that there has been no change in our affairs since the date of this prospectus or such prospectus supplement or that the information contained by reference to this prospectus or any prospectus supplement is correct as of any time after its date

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or SEC, using a "shelf" registration process. Under this shelf registration process, we may from time to time offer and sell, in one or more offerings, any or all of the securities described in this prospectus, separately or together, up to an aggregate offering price of $100,000,000. This prospectus provides you with a general description of our securities being offered. When we issue the securities being offered by this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the heading "Additional Information" and "Incorporation of Certain Information by Reference."

PROSPECTUS SUMMARY

The following summary highlights some information from this prospectus. It is not complete and does not contain all of the information that you should consider before making an investment decision. You should read this entire prospectus, including the "Risk Factors" section on page 3 and the disclosures to which that section refers you, the financial statements and related notes and the other more detailed information appearing elsewhere or incorporated by reference into this prospectus before investing in any of the securities described in this prospectus.

Corporate Overview

We are a clinical stage, biopharmaceutical company focused on the development and commercialization of new cancer therapies. We are dedicated to the development of novel cancer therapies for patients with unmet medical needs. Our mission is to benefit patients by developing and commercializing anti-cancer therapies for patients whose solid tumors exhibit features that make them resistant to, or unlikely to respond to, currently available therapies, with particular focus on orphan cancer indications.

Our two lead candidates are VAL-083, a novel, validated, DNA-targeting agent, for the treatment of drug-resistant solid tumors such as glioblastoma multiforme and potentially other solid tumors, including ovarian cancer, non-small cell lung cancer and diffuse intrinsic pontine glioma and REM-001, a late-stage photodynamic therapy ("PDT") for the treatment of cutaneous metastatic breast cancer. PDT is a treatment that uses light sensitive compounds, or photosensitizers, that, when exposed to specific wavelengths of light, act as a catalyst to produce a form of oxygen that induces local tumor cell death.

Corporate Information

Our address is 12707 High Bluff Dr., Suite 200, San Diego, CA 92130 and our telephone number is (858) 350-4364. Our corporate website is: www.kintara.com. The content of our website shall not be deemed incorporated by reference in this prospectus and you should not consider such information as part of this prospectus.

RISK FACTORS

Before purchasing any of the securities you should carefully consider the risk factors contained herein as well as incorporated by reference in this prospectus from our Annual Report on Form 10-K for the fiscal year ended June 30, 2020 and any subsequent updates described in our Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as the risks, uncertainties and additional information set forth in our SEC reports on Forms 10-K, 10-Q and 8-K and in the other documents incorporated by reference in this prospectus, including any prospectus supplement. For a description of these reports and documents, and information about where you can find them, see "Additional Information" and "Incorporation of Certain Information By Reference." Additional risks not presently known or that we presently consider to be immaterial could subsequently materially and adversely affect our financial condition, results of operations, business and prospects.

1

We have expressed substantial doubt about our ability to continue as a going concern.

As discussed in Note 1 to the condensed consolidated interim financial statements for the quarter ended December 31, 2020, our unaudited financial statements for the fiscal quarter ended December 31, 2020, include an explanatory paragraph that such financial statements were prepared assuming that we will continue as a going concern. A going concern basis assumes that we will continue our operations for the foreseeable future and contemplates the realization of assets and the settlement of liabilities in the normal course of business.

For the six months ended December 31, 2020, we reported a loss of $24.9 million, and a negative cash flow from operations of $9.5 million. We had an accumulated deficit of $97.8 million as of December 31, 2020. As of December 31, 2020, we had cash and cash equivalents on hand of $17.2 million. We are in the clinical stage and have not generated any revenues to-date. We do not have the prospect of achieving revenues until such time that our product candidates are commercialized, or partnered, which may not ever occur. In the future, we will require additional funding to maintain our clinical studies, research and development projects, and for general operations. These circumstances indicate substantial doubt exists about our ability to continue as a going concern.

Consequently, management is pursuing various financing alternatives to fund our operations so we can continue as a going concern. However, the coronavirus ("COVID-19") pandemic has created significant economic uncertainty and volatility in the credit and capital markets. Management plans to secure the necessary financing through the issue of new equity and/or the entering into of strategic partnership arrangements but the ultimate impact of the COVID-19 pandemic on the our ability to raise additional capital is unknown and will depend on future developments, which are highly uncertain and cannot be predicted with confidence, including the duration of the COVID-19 outbreak and any new information which may emerge concerning the severity of the COVID-19 pandemic. We may not be able to raise sufficient additional capital and may tailor our drug candidate development program based on the amount of funding we are able to raise in the future. Nevertheless, there is no assurance that these initiatives will be successful.

The condensed consolidated interim financial statements for the quarter ended December 31, 2020 do not give effect to any adjustments to the financial statements and classification of assets and liabilities that may be necessary should we be unable to continue as a going concern. Such adjustments could be material.

FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference, contains forward-looking statements as that term is defined in the federal securities laws. The events described in forward-looking statements contained in this prospectus, including the documents that we incorporate by reference, may not occur. Generally, these statements relate to our business plans or strategies, projected or anticipated benefits or other consequences of our plans or strategies, financing plans, projected or anticipated benefits from acquisitions that we may make, or projections involving anticipated revenues, earnings or other aspects of our operating results or financial position, and the outcome of any contingencies. Any such forward-looking statements are based on current expectations, estimates and projections of management. We intend for these forward-looking statements to be covered by the safe-harbor provisions for forward-looking statements. Words such as "may," "expect," "believe," "anticipate," "project," "plan," "intend," "estimate," and "continue," and their opposites and similar expressions are intended to identify forward-looking statements. We caution you that these statements are not guarantees of future performance or events and are subject to a number of uncertainties, risks and other influences, many of which are beyond our control that may influence the accuracy of the statements and the projections upon which the statements are based. Factors that may affect our results include, but are not limited to, the risks and uncertainties discussed in the "Risk Factors" section on page 3 of this prospectus, in our Annual Report on Form 10-K for the fiscal year ended June 30, 2020 or in other reports we file with the Securities and Exchange Commission.

Any one or more of these uncertainties, risks and other influences could materially affect our results of operations and whether forward-looking statements made by us ultimately prove to be accurate. Our actual results, performance and achievements could differ materially from those expressed or implied in these forward-looking statements. We undertake no obligation to publicly update or revise any forward-looking statements, whether from new information, future events or otherwise.

2

You should rely only on the information in this prospectus. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it.

USE OF PROCEEDS

Unless we inform you otherwise in the prospectus supplement relating to a particular offering of securities, we will use the net proceeds from the sale of the securities offered by this prospectus and the exercise price from the exercise of any convertible securities, if any, for working capital and other general corporate purposes, which may include funding acquisitions or investments in businesses, products or technologies that are complementary to our own and reducing indebtedness.

When particular securities are offered, the prospectus supplement relating to that offering will set forth our intended use of the net proceeds received from the sale of those securities we sell. Pending the application of the net proceeds for these purposes, we expect to invest the proceeds in short-term, interest-bearing instruments or other investment-grade securities.

THE SECURITIES WE MAY OFFER

General

The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize all of the material terms and provisions of the various types of securities that we may offer. We will describe in the applicable prospectus supplement relating to any securities the particular terms of the securities offered by that prospectus supplement. If we indicate in the applicable prospectus supplement, the terms of the securities may differ from the terms we have summarized below. We may also include in the prospectus supplement information about material United States federal income tax considerations relating to the securities, and the securities exchange, if any, on which the securities will be listed.

We may sell from time to time, in one or more offerings:

In this prospectus, we refer to the common stock, preferred stock, warrants, debt securities, subscription rights and units collectively as "securities." The total dollar amount of all securities that we may sell pursuant to this prospectus will not exceed $100,000,000.

If we issue debt securities at a discount from their original stated principal amount, then, for purposes of calculating the total dollar amount of all securities issued under this prospectus, we will treat the initial offering price of the debt securities as the total original principal amount of the debt securities.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

3

DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock is a summary and does not purport to be complete. It is subject to and qualified in its entirety by reference to our articles of incorporation, as amended (the "Articles of Incorporation") and our bylaws, as amended (the "Bylaws"), each of which is incorporated by reference as exhibits to the registration statement of which this prospectus is a part. We encourage you to read our Articles of Incorporation, our Bylaws and the applicable provisions of the Nevada Revised Statutes, as amended ("NRS"), for additional information.

Authorized Stock

We are authorized to issue up to 100,000,000 shares of capital stock, including 95,000,000 shares of common stock, par value $0.001 per share, and 5,000,000 shares of preferred stock, par value $0.001 per share.

The additional shares of our authorized stock available for issuance may be issued at times and under circumstances so as to have a dilutive effect on earnings per share and on the equity ownership of the holders of our common stock. The ability of our board of directors to issue additional shares of stock could enhance the board's ability to negotiate on behalf of the stockholders in a takeover situation but could also be used by the board to make a change-in-control more difficult, thereby denying stockholders the potential to sell their shares at a premium and entrenching current management.

Common Stock

Each outstanding share of our common stock entitles the holder to one vote, either in person or by proxy, on all matters submitted to a vote of stockholders, including the election of directors. There is no cumulative voting in the election of directors. All actions required or permitted to be taken by stockholders at an annual or special meeting of the stockholders must be effected at a duly called meeting, with a quorum present of a majority in voting power of the shares entitled to vote thereon. Special meetings of the stockholders may only be called by our board of directors acting pursuant to a resolution approved by the affirmative majority of the entire board of directors. Stockholders may not take action by written consent. A vote by the holders of a majority of our outstanding shares is required to effectuate certain fundamental corporate changes such as liquidation, merger or an amendment to our articles of incorporation.

Subject to preferences which may be applicable to any outstanding shares of preferred stock from time to time, holders of our common stock have equal ratable rights to such dividends as may be declared from time to time by our board of directors out of funds legally available therefor. In the event of any liquidation, dissolution or winding-up of our affairs, holders of our common stock will be entitled to share ratably in our remaining assets after provision for payment of amounts owed to creditors and preferences applicable to any outstanding shares of preferred stock. All outstanding shares our common stock are fully paid and nonassessable. Holders of our common stock do not have preemptive rights.

The rights, preferences and privileges of holders of our common stock are subject to the rights of the holders of any outstanding shares of preferred stock.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Mountain Share Transfer, Inc. The transfer agent address is 2030 Powers Ferry Road SE, Suite #212, Atlanta, GA 30339, (404)-474-3110.

Preferred Stock

Our board of directors is authorized to issue up to 5,000,000 shares of preferred stock, par value $0.001 per share, in one or more series, 3,693,070 of which shares are undesignated, with such designations, rights and preferences as may be determined from time to time by our board of directors. Accordingly, our board of directors is empowered, without stockholder approval, to issue preferred stock with dividend, liquidation, conversion, voting, or other rights that could adversely affect the voting power or other rights of the holders of our common stock. The issuance of preferred stock could have the effect of decreasing the market price of the common stock, impeding or delaying a possible takeover and adversely affecting the voting and other rights of the holders of our common stock.

4

Series A Preferred Stock

Our board of directors previously established a series of preferred stock designated as Series A Preferred Stock ("Series A Preferred Stock"), comprising 278,530 shares of preferred stock. Subject to superior rights of any other outstanding preferred stock from time to time, each outstanding share of Series A Preferred Stock is entitled to receive, in preference to our common stock, cumulative dividends, payable quarterly in arrears, at an annual rate of 3% of $1.00 per share (the "Series A Stated Value"). We have never paid dividends on shares of our common stock and we do not intend to do so for the foreseeable future. Series A Preferred Stock does not have any voting rights. In the event of liquidation, each share of Series A Preferred Stock is entitled to receive, in preference to our common stock and pari passu with the Series B Preferred Stock and Series C Preferred Stock, a liquidation payment equal to the Series A Stated Value (as adjusted for stock splits, stock dividends, combinations or other recapitalizations of the Series A Preferred Stock), plus any accrued and unpaid dividends. If there are insufficient funds to permit full payment, the assets legally available for distribution will be distributed pro rata among the holders of the Series A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock. The Series A Preferred Stock cannot be transferred without our prior written consent.

Series B Preferred Stock

Our board of directors previously established a series of preferred stock designated as Series B Preferred Stock ("Series B Preferred Stock"), comprising 1,000,000 shares of preferred stock. Subject to superior rights of any other outstanding preferred our from time to time, each outstanding share of Series B Preferred Stock is entitled to receive, in preference to our common stock and pari passu with the Series A Preferred Stock and Series C Preferred Stock, annual cumulative dividends equal to 9% of $8.00 per share (the "Series B Stated Value"), accruing quarterly on the date of issue and payable quarterly in arrears on December 31, March 31, June 30 and September 30 of each year. At the time shares of Series B Preferred Stock are converted into our common stock, accrued and unpaid dividends will be paid in shares of our common stock. In the event we elect to declare any dividends on our common stock, the Series B Preferred Stock is entitled to participate in such dividends on an as-converted basis. We have never paid dividends on shares of our common stock and we do not intend to do so for the foreseeable future. Series B Preferred Stock is entitled to vote with our common stock, on an as-converted basis, as a single class. In the event of liquidation, each share of Series B Preferred Stock is entitled to receive, in preference to our common stock and pari passu with the Series A Preferred Stock and Series C Preferred Stock, a liquidation payment equal to the Series B Stated Value plus any accrued and unpaid dividends. If there are insufficient funds to permit full payment, the assets legally available for distribution will be distributed pro rata among the holders of the A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock.

Each share of Series B Preferred Stock may be converted into 0.25 fully paid shares our common stock at the option of a holder as long as we have sufficient authorized and unissued shares our common stock available. The conversion rate may be adjusted in the event of a reverse stock split, merger or reorganization. The Series B Preferred Stock will automatically convert into our common stock on the earlier of (i) April 29, 2021, or (ii) upon the approval of VAL-083 by the U.S. Food and Drug Administration or the European Medicines Agency so long as the closing bid price our common stock at the time of such approval is at least $80.00 per share.

Series C Preferred Stock

Our board of directors previously established a series of preferred stock designated as Series C Preferred Stock ("Series C Preferred Stock"), comprised of three classes: 22,000 shares have been designated as Series C-1 Preferred Stock, 2,700 shares have been designated as Series C-2 Preferred Stock and 3,700 shares have been designated as Series C-3 Preferred Stock. Each class of Series C Preferred Stock has identical terms, except for the Conversion Price of the particular class of Series C Preferred Stock.

Dividends. The Series C Preferred Stock will be entitled to receive dividends, payable in shares our common stock at a rate of 10%, 15%, 20% and 25% of the number of shares our common stock issuable upon conversion of the Series C Preferred Stock, on the 12th, 24th, 36th and 48th month, anniversary of the initial closing of the private placement offering of the Series C Preferred Stock (the "Private Placement"), which occurred on August 19, 2020. Dividends will be payable in shares our common stock and will only be payable to those holders that continue to hold the Series C Preferred Stock on the respective anniversary dates of August 19, 2020. In addition, each holder of Series C

5

Preferred Stock will be entitled to receive dividends equal, on an as-converted to shares of our common stock basis, to and in the same form as dividends actually paid on shares our common stock when, as, and if such dividends are paid on shares our common stock. We have never paid dividends on shares our common stock and we do not intend to do so for the foreseeable future.

Rank. The Series C Preferred Stock will rank pari passu with the shares of Series A Preferred Stock and Series B Preferred Stock.

Liquidation. Upon any dissolution, liquidation or winding up, whether voluntary or involuntary, holders of Series C Preferred Stock, together with the Series A Preferred Stock and Series B Preferred Stock, will be entitled to receive distributions out of our assets in an amount per share equal to $1,000 with respect to the Series C Preferred Stock (and $1.00 and $8.00 per share, respectively, for the Series A Preferred Stock and Series B Preferred Stock) plus all accrued and unpaid dividends, whether capital or surplus before any distributions shall be made on any shares our common stock.

Conversion. Upon the earlier of (i) the three and a half year anniversary of the initial closing of the Private Placement, which occurred on August 19, 2020, or (ii) the consent to conversion by holders of at least 50.1% of all of the then-outstanding shares of Series C Preferred Stock, without any action on the part of the holder, each share of Series C Preferred Stock will automatically convert into shares our common stock at the Conversion Price, as set forth below. In addition, each share of Series C Preferred Stock will be convertible, at any time and from time to time at the option of the holder, into that number of shares our common stock at the Conversion Price, subject to adjustment. The Conversion Price of the Series C Preferred Stock will equal the lesser of (i) the closing price of our common stock on Nasdaq on the date immediately preceding the signing of the applicable binding agreements for the applicable closing date of the Private Placement for which the Series C Preferred Stock is issued or (ii) the average closing price of our common stock on Nasdaq for the five trading days immediately preceding the signing of the applicable binding agreements for the applicable closing date of the Private Placement for which the Series C Preferred Stock is issued, subject to adjustment. The Conversion Prices for the Series C-1 Preferred Stock, Series C-2 Preferred Stock and Series C-3 Preferred Stock are $1.16, $1.214 and $1.15, respectively.

Conversion Price Adjustment:

Stock Dividends and Stock Splits. If we pay a stock dividend or otherwise make a distribution payable in shares our common stock on shares our common stock or any other common stock equivalents, subdivide or combine outstanding our common stock, or reclassify our common stock, the Conversion Price will be adjusted by multiplying the then conversion price by a fraction, the numerator of which shall be the number of shares our common stock outstanding immediately before such event, and the denominator of which shall be the number of shares outstanding immediately after such event.

Fundamental Transaction. If we effect a fundamental transaction, then upon any subsequent conversion of Series C Preferred Stock, the holder thereof shall have the right to receive, for each share our common stock that would have been issuable upon such conversion immediately prior to the occurrence of such fundamental transaction, the number of shares of the successor's or acquiring corporation's common stock or our common stock, if we are the surviving corporation, and any additional consideration receivable as a result of such fundamental transaction by a holder of the number of shares our common stock into which Series C Preferred Stock is convertible immediately prior to such fundamental transaction. A fundamental transaction means: (i) a merger or consolidation with or into another entity, (ii) any sale of all or substantially all of our assets in one transaction or a series of related transactions, or (iii) any reclassification our common stock or any compulsory share exchange by which our common stock is effectively converted into or exchanged for other securities, cash or property.

Voting Rights. Except as otherwise provided in the Certificate of Designation of Preferences, Rights and Limitations for the applicable class of Series C Preferred Stock (the "Certificate of Designation") or required by law, Series C Preferred Stock shall have no separate class voting rights. The Certificate of Designation provides that each share of Series C Preferred Stock will entitle its holder to vote with our common stock on an as-converted basis. Notwithstanding certain protections in the Certificate of Designation, Nevada law also provides holders of preferred stock with certain rights. The holders of the outstanding shares of Series C Preferred Stock generally will be entitled to vote as a class upon a proposed amendment to our Articles of Incorporation if the amendment would:

6

Fractional Shares. No fractional shares our common stock will be issued upon conversion of Series C Preferred Stock. Rather, we will round up to the next whole share.

Future Issuance of Preferred Stock

If we offer a specific series of preferred stock under this prospectus, we will describe the terms of the preferred stock in the prospectus supplement for such offering and will file a copy of the certificate establishing the terms of the preferred stock with the SEC. To the extent required, this description will include:

7

Transfer Agent and Registrar for Preferred Stock

The transfer agent and registrar for any series or class of preferred stock will be set forth in each applicable prospectus supplement.

Anti-takeover Effects of Nevada Law and our Articles of Incorporation, as amended, and Bylaws

Our Articles of Incorporation and Bylaws contain a number of provisions that could make our acquisition by means of a tender or exchange offer, a proxy contest or otherwise more difficult. Certain of these provisions are summarized below.

Special Meetings

Special meetings of the stockholders may only be called by our board of directors or such person or person authorized by the board of directors.

Business Combinations Act

The Business Combinations Act, Sections 78.411 to 78.444 of the NRS, restricts the ability of a Nevada "resident domestic corporation" having at least 200 stockholders of record to engage in any "combination" with an "interested stockholder" for two (2) years after the date that the person first became an interested stockholder, unless the combination meets all of the requirements of the articles of incorporation of the resident domestic corporation and (i) the purchase of shares by the interested stockholder is approved by the board of directors before that date or (ii) the combination is approved by the board of directors of the resident domestic corporation and, at or after that time, the combination is approved at an annual or special meeting of the stockholders of the resident domestic corporation, and not by written consent, by the affirmative vote of the holders of stock representing at least sixty percent (60%) of the outstanding voting power of the resident domestic corporation not beneficially owned by the interested stockholder or the affiliates or associates of the interested stockholder.

If this approval is not obtained, then after the expiration of the two (2) year period, the business combination may still not be consummated unless it is a combination meeting all of the requirements of the articles of incorporation of the resident domestic corporation and either the "fair price" requirements specified in NRS 78.441 to 78.444, inclusive are satisfied or the combination is (a) a combination or transaction by which the person first became an interested stockholder is approved by the board of directors of the resident domestic corporation before the person first became an interested stockholder, or (b) a combination approved by a majority of the outstanding voting power of the resident domestic corporation not beneficially owned by the interested stockholder, or any affiliate or associate of the interested stockholder.

"Interested stockholder" means any person, other than the resident domestic corporation or its subsidiaries, who is (a) the beneficial owner, directly or indirectly, of 10% or more of the voting power of the outstanding voting shares of the resident domestic corporation or (b) an affiliate or associate of the resident domestic corporation and at any time within two years immediately before the date in question was the beneficial owner, directly or indirectly, of 10% or more of the voting power of the then outstanding shares of the resident domestic corporation.

8

A "combination" is broadly defined and includes, for example, any merger or consolidation of a corporation or any of its subsidiaries with (i) an interested stockholder or (ii) any other entity that after and as a result of the merger or consolidation would be an affiliate or associate of the interested stockholder; or any sale, lease, exchange, pledge, transfer or other disposition of assets of the corporation, in one transaction or a series of transactions, to or with an interested stockholder having: (x) an aggregate market value equal to more than 5% of the aggregate market value of the assets of a corporation, (y) an aggregate market value equal to more than 5% of the aggregate market value of all outstanding voting shares of a corporation, or (z) representing more than 10% of the earning power or net income of a corporation.

The provisions of Nevada law, our Articles of Incorporation and our Bylaws could have the effect of discouraging others from attempting hostile takeovers and, as a consequence, they may also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions may also have the effect of preventing changes in our management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

Control Shares

Nevada law also seeks to impede "unfriendly" corporate takeovers by providing in Sections 78.378 to 78.3793 of the NRS that an "acquiring person" shall only obtain voting rights in the "control shares" purchased by such person to the extent approved by the other shareholders at a meeting. With certain exceptions, an acquiring person is one who acquires or offers to acquire a "controlling interest" in the corporation, defined as one-fifth or more of the voting power. Control shares include not only shares acquired or offered to be acquired in connection with the acquisition of a controlling interest, but also all shares acquired by the acquiring person within the preceding 90 days. The statute covers not only the acquiring person but also any persons acting in association with the acquiring person.

A Nevada corporation may elect to opt out of the provisions of Sections 78.378 to 78.3793 of the NRS. We have no provision in our articles of incorporation pursuant to which we have elected to opt out of Sections 78.378 to 78.3793; therefore, these sections do apply to us.

Potential Effects of Authorized but Unissued Stock

We have shares of common stock and preferred stock available for future issuance without stockholder approval. We may utilize these additional shares for a variety of corporate purposes, including future public offerings to raise additional capital, to facilitate corporate acquisitions or payment as a dividend on the capital stock.

The existence of unissued and unreserved common stock and preferred stock may enable our board of directors to issue shares to persons friendly to current management or to issue preferred stock with terms that could render more difficult or discourage a third-party attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise, thereby protecting the continuity of our management. In addition, the board of directors has the discretion to determine designations, rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences of each series of preferred stock, all to the fullest extent permissible under the Nevada Revised Statute and subject to any limitations set forth in our articles of incorporation. The purpose of authorizing the board of directors to issue preferred stock and to determine the rights and preferences applicable to such preferred stock is to eliminate delays associated with a stockholder vote on specific issuances. The issuance of preferred stock, while providing desirable flexibility in connection with possible financings, acquisitions and other corporate purposes, could have the effect of making it more difficult for a third-party to acquire, or could discourage a third-party from acquiring, a majority of our outstanding voting stock.

DESCRIPTION OF STOCK WARRANTS

We summarize below some of the provisions that will apply to the warrants unless the applicable prospectus supplement provides otherwise. This summary may not contain all information that is important to you. The complete terms of the warrants will be contained in the applicable warrant certificate and warrant agreement. These documents have been or will be included or incorporated by reference as exhibits to the registration statement of which this prospectus is a part. You should read the warrant certificate and the warrant agreement. You should also read the

9

prospectus supplement, which will contain additional information and which may update or change some of the information below.

General

We may issue, together with common or preferred stock as units or separately, warrants for the purchase of shares of our common or preferred stock. The terms of each warrant will be discussed in the applicable prospectus supplement relating to the particular series of warrants. The form(s) of certificate representing the warrants and/or the warrant agreement will be, in each case, filed with the SEC as an exhibit to a document incorporated by reference in the registration statement of which this prospectus is a part on or prior to the date of any prospectus supplement relating to an offering of the particular warrant. The following summary of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to a particular series of warrants.

The prospectus supplement relating to any series of warrants that are offered by this prospectus will describe, among other things, the following terms to the extent they are applicable to that series of warrants:

Each warrant may entitle the holder to purchase for cash, or, in limited circumstances, by effecting a cashless exercise for, the number of shares of our common or preferred stock at the exercise price that is described in the applicable prospectus supplement. Warrants will be exercisable during the period of time described in the applicable prospectus supplement. After that period, unexercised warrants will be void. Warrants may be exercised in the manner described in the applicable prospectus supplement.

10

A holder of a warrant will not have any of the rights of a holder of our common or preferred stock before the stock is purchased upon exercise of the warrant. Therefore, before a warrant is exercised, the holder of the warrant will not be entitled to receive any dividend payments or exercise any voting or other rights associated with shares of our common or preferred stock which may be purchased when the warrant is exercised.

Transfer Agent and Registrar

The transfer agent and registrar, if any, for any warrants will be set forth in the applicable prospectus supplement.

DESCRIPTION OF DEBT SECURITIES

This prospectus describes certain general terms and provisions of debt securities that we may offer. The debt securities may be issued pursuant to, in the case of senior debt securities, a senior indenture, and in the case of subordinated debt securities, a subordinated indenture, in each case in the forms filed as exhibits to this registration statement, which we refer to as the "indentures." The indentures will be entered into between us and a trustee to be named prior to the issuance of any debt securities, which we refer to as the "trustee." The indentures will not limit the amount of debt securities that can be issued thereunder and will provide that the debt securities may be issued from time to time in one or more series pursuant to the terms of one or more securities resolutions or supplemental indentures creating such series.

We have summarized below the material provisions of the indentures and the debt securities or indicated which material provisions will be described in the related prospectus supplement for any offering of debt securities. These descriptions are only summaries, and you should refer to the relevant indenture for the particular offering of debt securities itself which will describe completely the terms and definitions of the offered debt securities and contain additional information about the debt securities.

Terms

When we offer to sell a particular series of debt securities, we will describe the specific terms of the securities in a prospectus supplement. The prospectus supplement will set forth the following terms, as applicable, of the debt securities offered thereby:

11

Debt securities of any series may be issued as registered debt securities or uncertificated debt securities, in such denominations as specified in the terms of the series.

Securities may be issued under the indentures as Discounted Debt Securities to be offered and sold at a substantial discount from the principal amount thereof. Special United States federal income tax and other considerations applicable thereto will be described in the prospectus supplement relating to such Discounted Debt Securities. "Discounted Debt Security" means a security where the amount of principal due upon acceleration is less than the stated principal amount.

We are not obligated to issue all debt securities of one series at the same time and, unless otherwise provided in the prospectus supplement, we may reopen a series, without the consent of the holders of the debt securities of that series, for the issuance of additional debt securities of that series. Additional debt securities of a particular series will have the same terms and conditions as outstanding debt securities of such series, except for the date of original issuance and the offering price, and will be consolidated with, and form a single series with, such outstanding debt securities.

Ranking

The senior debt securities will rank equally with all of our other senior and unsubordinated debt. Our secured debt, if any, will be effectively senior to the senior debt securities to the extent of the value of the assets securing such debt. The subordinated debt securities will be subordinate and junior in right of payment to all of our present and future senior indebtedness to the extent and in the manner described in the prospectus supplement and as set forth in the board resolution, officer's certificate or supplemental indenture relating to such offering.

We have only a stockholder's claim on the assets of our subsidiaries. This stockholder's claim is junior to the claims that creditors of our subsidiaries have against our subsidiaries. Holders of our debt securities will be our creditors and not creditors of any of our subsidiaries. As a result, all the existing and future liabilities of our subsidiaries, including any claims of their creditors, will effectively be senior to the debt securities with respect to the

assets of our subsidiaries. In addition, to the extent that we issue any secured debt, the debt securities will be effectively subordinated to such secured debt to the extent of the value of the assets securing such secured debt.

12

The debt securities will be obligations exclusively of Kintara Therapeutics, Inc. To the extent that our ability to service our debt, including the debt securities, may be dependent upon the earnings of our subsidiaries, our ability to do so will be dependent on the ability of our subsidiaries to distribute those earnings to us as dividends, loans or other payments.

Certain Covenants

Any covenants that may apply to a particular series of debt securities will be described in the prospectus supplement relating thereto.

Successor Obligor

The indentures will provide that, unless otherwise specified in the securities resolution or supplemental indenture establishing a series of debt securities, we shall not consolidate with or merge into, or transfer all or substantially all of our assets to, any person in any transaction in which we are not the survivor, unless:

In such event, the successor will be substituted for us, and thereafter all of our obligations under the relevant indenture, the debt securities and any coupons will terminate.

The indentures will provide that these limitations shall not apply if our board of directors makes a good faith determination that the principal purpose of the transaction is to change our state of incorporation.

Exchange of Debt Securities

Registered debt securities may be exchanged for an equal aggregate principal amount of registered debt securities of the same series and date of maturity in such authorized denominations as may be requested upon surrender of the registered debt securities at an agency of the Company maintained for such purpose and upon fulfillment of all other requirements of such agent.

Default and Remedies

Unless the securities resolution or supplemental indenture establishing the series otherwise provides (in which event the prospectus supplement will so state), an "Event of Default" with respect to a series of debt securities will occur if:

13

The term "Bankruptcy Law" means Title 11 of the United States Code or any similar Federal or State law for the relief of debtors. The term "Custodian" means any receiver, trustee, assignee, liquidator or a similar official under any Bankruptcy Law.

"Default" means any event which is, or after notice or passage of time would be, an Event of Default. A Default under subparagraph (3) above is not an Event of Default until the trustee or the holders of at least 25% in principal amount of the series notify us of the Default and we do not cure the Default within the time specified after receipt of the notice.

The trustee may require indemnity satisfactory to it before it enforces the indentures or the debt securities of the series. Subject to certain limitations, holders of a majority in principal amount of the debt securities of the series may direct the trustee in its exercise of any trust or power with respect to such series. Except in the case of Default in payment on a series, the trustee may withhold from securityholders of such series notice of any continuing Default if the trustee determines that withholding notice is in the interest of such securityholders. We are required to furnish the trustee annually a brief certificate as to our compliance with all conditions and covenants under the indentures.

The indentures will not have cross-default provisions. Thus, a default by us on any other debt, including any other series of debt securities, would not constitute an Event of Default.

Amendments and Waivers

The indentures and the debt securities or any coupons of the series may be amended, and any Default may be waived as follows:

Unless the securities resolution or supplemental indenture otherwise provides (in which event the applicable prospectus supplement will so state), the debt securities and the indentures may be amended with the consent of the holders of a majority in principal amount of the debt securities of all series affected voting as one class. Unless the securities resolution or supplemental indenture otherwise provides (in which event the applicable prospectus supplement will so state), a Default other than a Default in payment on a particular series may be waived with the consent of the holders of a majority in principal amount of the debt securities of the series. However, without the consent of each securityholder affected, no amendment or waiver may:

14

Without the consent of any securityholder, the indentures or the debt securities may be amended to:

15

Conversion Rights

Any securities resolution or supplemental indenture establishing a series of debt securities may provide that the debt securities of such series will be convertible at the option of the holders thereof into or for our common stock or other equity or debt instruments. The securities resolution or supplemental indenture may establish, among other things, (1) the number or amount of shares of common stock or other equity or debt instruments for which $1,000 aggregate principal amount of the debt securities of the series is convertible, as may be adjusted pursuant to the terms of the relevant indenture and the securities resolution; and (2) provisions for adjustments to the conversion rate and limitations upon exercise of the conversion right. The indentures provide that we will not be required to make an adjustment in the conversion rate unless the adjustment would require a cumulative change of at least 1% in the conversion rate. However, we will carry forward any adjustments that are less than 1% of the conversion rate and take them into account in any subsequent adjustment of the conversion rate.

Legal Defeasance and Covenant Defeasance

Debt securities of a series may be defeased in accordance with their terms and, unless the securities resolution or supplemental indenture establishing the terms of the series otherwise provides, as set forth below. We at any time may terminate as to a series all of our obligations (except for certain obligations, including obligations with respect to the defeasance trust and obligations to register the transfer or exchange of a debt security, to replace destroyed, lost or stolen debt securities and coupons and to maintain paying agencies in respect of the debt securities) with respect to the debt securities of the series and any related coupons and the relevant indenture, which we refer to as legal defeasance. We at any time may terminate as to a series our obligations with respect to any restrictive covenants which may be applicable to a particular series, which we refer to as covenant defeasance.

We may exercise our legal defeasance option notwithstanding our prior exercise of our covenant defeasance option. If we exercise our legal defeasance option, a series may not be accelerated because of an Event of Default. If we exercise our covenant defeasance option, a series may not be accelerated by reference to any covenant which may be applicable to a series.

To exercise either defeasance option as to a series, we must (1) irrevocably deposit in trust with the trustee (or another trustee) money or U.S. Government Obligations (as defined below), deliver a certificate from a nationally recognized firm of independent accountants expressing their opinion that the payments of principal and interest when due on the deposited U.S. Government Obligations, without reinvestment, plus any deposited money without investment will provide cash at such times and in such amounts as will be sufficient to pay the principal and interest when due on all debt securities of such series to maturity or redemption, as the case may be; and (2) comply with certain other conditions. In particular, we must obtain an opinion of tax counsel that the defeasance will not result in recognition of any gain or loss to holders for federal income tax purposes.

"U.S. Government Obligations" means direct obligations of the United States or any agency or instrumentality of the United States, the payment of which is unconditionally guaranteed by the United States, which, in either case, have the full faith and credit of the United States pledged for payment and which are not callable at the issuer's option, or certificates representing an ownership interest in such obligations.

Regarding the Trustee

16

Unless otherwise indicated in a prospectus supplement, the trustee will also act as depository of funds, transfer agent, paying agent and conversion agent, as applicable, with respect to the debt securities. In certain circumstances, we or the securityholders may remove the trustee as the trustee under a given indenture. The indenture trustee may also provide additional unrelated services to us as a depository of funds, registrar, trustee and similar services.

Governing Law

The indentures and the debt securities will be governed by New York law, except to the extent that the Trust Indenture Act of 1939 is applicable.

DESCRIPTION OF SUBSCRIPTION RIGHTS

We may issue subscription rights to purchase our common stock or debt securities. These subscription rights may be offered independently or together with any other security offered hereby and may or may not be transferable by the stockholder receiving the subscription rights in such offering. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The prospectus supplement relating to any subscription rights we offer, if any, will, to the extent applicable, include specific terms relating to the offering, including some or all of the following:

17

DESCRIPTION OF UNITS

We may issue units comprised of one or more of the other securities described in this prospectus in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security (but, to the extent convertible securities are included in the units, the holder of the units will be deemed the holder of the convertible securities and not the holder of the underlying securities). The unit agreement under which a unit is issued, if any, may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

This summary of certain general terms of units and any summary description of units in the applicable prospectus supplement do not purport to be complete and are qualified in their entirety by reference to all provisions of the applicable unit agreement and, if applicable, collateral arrangements and depositary arrangements relating to such units. The forms of the unit agreements and other documents relating to a particular issue of units will be filed with the SEC each time we issue units, and you should read those documents for provisions that may be important to you.

FORMS OF SECURITIES

Each debt security and, to the extent applicable, warrant, subscription right and unit, will be represented either by a certificate issued in definitive form to a particular investor or by one or more global securities representing the entire issuance of securities. Certificated securities in definitive form and global securities will be issued in registered form. Definitive securities name you or your nominee as the owner of the security, and in order to transfer or exchange these securities or to receive payments other than interest or other interim payments, you or your nominee must physically deliver the securities to the trustee, registrar, paying agent or other agent, as applicable. Global securities name a depositary or its nominee as the owner of the debt securities or warrants represented by these global securities. The depositary maintains a computerized system that will reflect each investor's beneficial ownership of the securities through an account maintained by the investor with its broker/dealer, bank, trust company or other representative, as we explain more fully below.

Global Securities

Registered Global Securities. We may issue the registered debt securities and, to the extent applicable, warrants, subscription rights and units, in the form of one or more fully registered global securities that will be deposited with a depositary or its nominee identified in the applicable prospectus supplement and registered in the name of that depositary or nominee. In those cases, one or more registered global securities will be issued in a denomination or aggregate denominations equal to the portion of the aggregate principal or face amount of the

securities to be represented by registered global securities. Unless and until it is exchanged in whole for securities in definitive registered form, a registered global security may not be transferred except as a whole by and among the

18

depositary for the registered global security, the nominees of the depositary or any successors of the depositary or those nominees.

If not described below, any specific terms of the depositary arrangement with respect to any securities to be represented by a registered global security will be described in the prospectus supplement relating to those securities. We anticipate that the following provisions will apply to all depositary arrangements.

Ownership of beneficial interests in a registered global security will be limited to persons, called participants, that have accounts with the depositary or persons that may hold interests through participants. Upon the issuance of a registered global security, the depositary will credit, on its book-entry registration and transfer system, the participants' accounts with the respective principal or face amounts of the securities beneficially owned by the participants. Any dealers, underwriters or agents participating in the distribution of the securities will designate the accounts to be credited. Ownership of beneficial interests in a registered global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary, with respect to interests of participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some states may require that some purchasers of securities take physical delivery of these securities in definitive form. These laws may impair your ability to own, transfer or pledge beneficial interests in registered global securities.

So long as the depositary, or its nominee, is the registered owner of a registered global security, that depositary or its nominee, as the case may be, will be considered the sole owner or holder of the securities represented by the registered global security for all purposes under the applicable indenture or warrant agreement. Except as described below, owners of beneficial interests in a registered global security will not be entitled to have the securities represented by the registered global security registered in their names, will not receive or be entitled to receive physical delivery of the securities in definitive form and will not be considered the owners or holders of the securities under the applicable indenture or warrant agreement. Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for that registered global security and, if that person is not a participant, on the procedures of the participant through which the person owns its interest, to exercise any rights of a holder under the applicable indenture or warrant agreement. We understand that under existing industry practices, if we request any action of holders or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder is entitled to give or take under the applicable indenture or warrant agreement, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take that action, and the participants would authorize beneficial owners owning through them to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them.

Principal, premium, if any, interest payments on debt securities and any payments to holders with respect to warrants represented by a registered global security registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the registered global security. None of the Company, the trustees, the warrant agents or any other agent of the Company, the trustees or the warrant agents will have any responsibility or liability for any aspect of the records relating to payments made on account of beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to those beneficial ownership interests.

We expect that the depositary for any of the securities represented by a registered global security, upon receipt of any payment of principal, premium, interest or other distribution of underlying securities or other property to holders on that registered global security, will immediately credit participants' accounts in amounts proportionate to their respective beneficial interests in that registered global security as shown on the records of the depositary. We also expect that payments by participants to owners of beneficial interests in a registered global security held through participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers in bearer form or registered in "street name," and will be the responsibility of those participants.

If the depositary for any of these securities represented by a registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Securities Exchange Act of

19

1934, as amended, or the Exchange Act, and a successor depositary registered as a clearing agency under the Exchange Act is not appointed by us within 90 days, we will issue securities in definitive form in exchange for the registered global security that had been held by the depositary. Any securities issued in definitive form in exchange for a registered global security will be registered in the name or names that the depositary gives to the relevant trustee or warrant agent or other relevant agent of ours or theirs. It is expected that the depositary's instructions will be based upon directions received by the depositary from participants with respect to ownership of beneficial interests in the registered global security that had been held by the depositary.

PLAN OF DISTRIBUTION

Initial Offering and Sale of Securities

Unless otherwise set forth in a prospectus supplement accompanying this prospectus, we may sell the securities being offered hereby, from time to time, by one or more of the following methods:

Offerings of securities covered by this prospectus also may be made into an existing trading market for those securities in transactions at other than a fixed price, either:

Those at-the-market offerings, if any, will be conducted by underwriters acting as principal or agent of the Company, who may also be third-party sellers of securities as described above. The prospectus supplement with respect to the offered securities will set forth the terms of the offering of the offered securities, including:

20

The distribution of the securities may be effected from time to time in one or more transactions:

Each prospectus supplement will set forth the manner and terms of an offering of securities including:

In addition, we may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. The applicable prospectus supplement may indicate, in connection with such a transaction, that the third parties may sell securities covered by and pursuant to this prospectus and an applicable prospectus supplement. If so, the third party may use securities pledged by us or borrowed from us or others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and an applicable prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and the applicable prospectus supplement.

Sales Through Underwriters

If underwriters are used in the sale of some or all of the securities covered by this prospectus, the underwriters will acquire the securities for their own account. The underwriters may resell the securities, either directly to the public or to securities dealers, at various times in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to certain conditions. Unless indicated otherwise in a prospectus supplement, the underwriters will be obligated to purchase all the securities of the series offered if any of the securities are purchased.

Any initial public offering price and any concessions allowed or reallowed to dealers may be changed intermittently.

Sales Through Agents

Unless otherwise indicated in the applicable prospectus supplement, when securities are sold through an agent, the designated agent will agree, for the period of its appointment as agent, to use specified efforts to sell the securities for our account and will receive commissions from us as will be set forth in the applicable prospectus supplement.

Securities bought in accordance with a redemption or repayment under their terms also may be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing by one or more firms acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with the securities remarketed by them.

If so indicated in the applicable prospectus supplement, we may authorize agents, underwriters or dealers to solicit offers by certain specified institutions to purchase securities at a price set forth in the prospectus supplement pursuant

21

to delayed delivery contracts providing for payment and delivery on a future date specified in the prospectus supplement. These contracts will be subject only to those conditions set forth in the applicable prospectus supplement, and the prospectus supplement will set forth the commissions payable for solicitation of these contracts.

Direct Sales

We may also sell offered securities directly to institutional investors or others. In this case, no underwriters or agents would be involved. The terms of such sales will be described in the applicable prospectus supplement.

General Information

Broker-dealers, agents or underwriters may receive compensation in the form of discounts, concessions or commissions from us and/or the purchasers of securities for whom such broker-dealers, agents or underwriters may act as agents or to whom they sell as principal, or both. This compensation to a particular broker-dealer might be in excess of customary commissions.

Underwriters, dealers and agents that participate in any distribution of the offered securities may be deemed "underwriters" within the meaning of the Securities Act of 1933, as amended, or the Securities Act, so any discounts or commissions they receive in connection with the distribution may be deemed to be underwriting compensation. Those underwriters and agents may be entitled, under their agreements with us, to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or to contribution by us to payments that they may be required to make in respect of those civil liabilities. Certain of those underwriters or agents may be customers of, engage in transactions with, or perform services for, us or our affiliates in the ordinary course of business. We will identify any underwriters or agents, and describe their compensation, in a prospectus supplement. Any institutional investors or others that purchase offered securities directly, and then resell the securities, may be deemed to be underwriters, and any discounts or commissions received by them from us and any profit on the resale of the securities by them may be deemed to be underwriting discounts and commissions under the Securities Act.

We will file a supplement to this prospectus, if required, pursuant to Rule 424(b) under the Securities Act, if we enter into any material arrangement with a broker, dealer, agent or underwriter for the sale of securities through a block trade, special offering, exchange distribution or secondary distribution or a purchase by a broker or dealer. Such prospectus supplement will disclose:

22

In order to facilitate the offering of certain securities under this prospectus or an applicable prospectus supplement, certain persons participating in the offering of those securities may engage in transactions that stabilize, maintain or otherwise affect the price of those securities during and after the offering of those securities. Specifically, if the applicable prospectus supplement permits, the underwriters of those securities may over-allot or otherwise create a short position in those securities for their own account by selling more of those securities than have been sold to them by us and may elect to cover any such short position by purchasing those securities in the open market.

In addition, the underwriters may stabilize or maintain the price of those securities by bidding for or purchasing those securities in the open market and may impose penalty bids, under which selling concessions allowed to syndicate members or other broker-dealers participating in the offering are reclaimed if securities previously distributed in the offering are repurchased in connection with stabilization transactions or otherwise. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. The imposition of a penalty bid may also affect the price of securities to the extent that it discourages resales of the securities. No representation is made as to the magnitude or effect of any such stabilization or other transactions. Such transactions, if commenced, may be discontinued at any time.

In order to comply with the securities laws of certain states, if applicable, the securities must be sold in such jurisdictions only through registered or licensed brokers or dealers. In addition, in certain states the securities may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

Rule 15c6-1 under the Exchange Act generally requires that trades in the secondary market settle in two business days, unless the parties to any such trade expressly agree otherwise. Your prospectus supplement may provide that the original issue date for your securities may be more than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the second business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than two scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

This prospectus, any applicable prospectus supplement and any applicable pricing supplement in electronic format may be made available on the Internet sites of, or through other online services maintained by, us and/or one or more of the agents and/or dealers participating in an offering of securities, or by their affiliates. In those cases, prospective investors may be able to view offering terms online and, depending upon the particular agent or dealer, prospective investors may be allowed to place orders online.

Other than this prospectus, any applicable prospectus supplement and any applicable pricing supplement in electronic format, the information on our website or the website of any agent or dealer, and any information contained in any other website maintained by any agent or dealer:

There can be no assurance that we will sell all or any of the securities offered by this prospectus.

This prospectus may also be used in connection with any issuance of common stock or preferred stock upon exercise of a warrant if such issuance is not exempt from the registration requirements of the Securities Act.

23

In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing securityholders. In some cases, we or dealers acting with us or on our behalf may also purchase securities and reoffer them to the public by one or more of the methods described above. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

LEGAL MATTERS

Unless otherwise indicated in the applicable prospectus supplement, the validity of the issuance of the securities offered hereby will be passed upon for us by Fennemore Craig, P.C., Reno, Nevada. Lowenstein Sandler, LLP, New York, New York, will pass upon certain legal matters relating to the issuance and sale of the securities offered hereby. If the validity of the securities offered hereby in connection with offerings made pursuant to this prospectus are passed upon by counsel for the underwriters, dealers or agents, if any, such counsel will be named in the prospectus supplement relating to such offering.

EXPERTS

The consolidated balance sheet of Kintara Therapeutics, Inc. as of June 30, 2020, and the related consolidated statements of operations, stockholders' equity and cash flows for the year then ended, have been audited by Marcum LLP, an independent registered public accounting firm, as stated in their report which is incorporated herein by reference. Such consolidated financial statements have been incorporated herein by reference in reliance on the report of such firm given upon their authority as experts in accounting and auditing.

The consolidated financial statements of Kintara Therapeutics, Inc. at June 30, 2019, and for the year then ended, appearing in Kintara Therapeutics, Inc.'s Annual Report (Form 10-K) for the year ended June 30, 2020, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

DISCLOSURE OF COMMISSION POSITION

ON INDEMNIFICATION FOR SECURITIES ACT LIABILITIES

Neither our Articles of Incorporation, as amended, or our Bylaws, as amended, prevent us from indemnifying our officers, directors and agents to the extent permitted under the Nevada Revised Statute ("NRS"). NRS Section 78.751 provides that a corporation shall indemnify any director, officer, employee or agent of a corporation against expenses, including attorneys' fees, actually and reasonably incurred by him in connection with any the defense to the extent that a director, officer, employee or agent of a corporation has been successful on the merits or otherwise in defense of any action, suit or proceeding referred to Section 78.7502(1) or 78.7502(2), or in defense of any claim, issue or matter therein.

NRS Section 78.7502(1) provides that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative, except an action by or in the right of the corporation, by reason of the fact that he is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses, including attorneys' fees, judgments, fines and amounts paid in settlement actually and reasonably incurred by him in connection with the action, suit or proceeding if he: (a) is not liable pursuant to NRS Section 78.138; or (b) acted in good faith and in a manner which he reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful.

NRS Section 78.7502(2) provides that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor, by reason of the fact that he is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation,

24

partnership, joint venture, trust or other enterprise against expenses, including amounts paid in settlement and attorneys' fees actually and reasonably incurred by him in connection with the defense or settlement of the action or suit if he: (a) is not liable pursuant to NRS Section 78.138; or (b) acted in good faith and in a manner which he reasonably believed to be in or not opposed to the best interests of the corporation. Indemnification may not be made for any claim, issue or matter as to which such a person has been adjudged by a court of competent jurisdiction, after exhaustion of all appeals there from, to be liable to the corporation or for amounts paid in settlement to the corporation, unless and only to the extent that the court in which the action or suit was brought or other court of competent jurisdiction determines upon application that in view of all the circumstances of the case, the person is fairly and reasonably entitled to indemnity for such expenses as the court deems proper.

NRS Section 78.747 provides that except as otherwise provided by specific statute, no stockholder, director or officer of a corporation is individually liable for a debt or liability of the corporation, unless the director or officer acts as the alter ego of the corporation. The court as a matter of law must determine the question of whether a director or officer acts as the alter ego of a corporation.

Insofar as indemnification for liabilities arising under the Securities Act, may be permitted to directors, officers or controlling persons of ours, pursuant to the foregoing provisions, or otherwise, we have been informed that, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such a director, officer or controlling person in connection with the securities being registered, we will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification is against public policy as expressed hereby in the Securities Act and we will be governed by the final adjudication of such issue.

We have entered agreements to indemnify our directors and officers to the maximum extent allowed under Nevada law. These agreements, among other things, indemnify our directors and officers for certain expenses (including attorneys' fees), judgments, fines and settlement amounts reasonably incurred by such person in any action or proceeding, including any action by or in our right, on account of any services undertaken by such person on behalf of the Company or that person's status as a member of our board of directors.

ADDITIONAL INFORMATION

This prospectus is part of a Registration Statement on Form S-3 that we have filed with the SEC relating to the shares of our securities being offered hereby. This prospectus does not contain all of the information in the Registration Statement and its exhibits. The Registration Statement, its exhibits and the documents incorporated by reference in this prospectus and their exhibits, all contain information that is material to the offering of the securities hereby. Whenever a reference is made in this prospectus to any of our contracts or other documents, the reference may not be complete. You should refer to the exhibits that are a part of the Registration Statement in order to review a copy of the contract or documents. The Registration Statement and the exhibits are available at the SEC's Public Reference Room or through its website.

We file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC maintains an Internet site at http://www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers, such as us, that file electronically with the SEC. Additionally, you may access our filings with the SEC through our website at www.kintara.com. We have included our website address as an inactive textual reference only and our website and the information contained on, or that can be accessed through, our website will not be deemed to be incorporated by reference in, and are not considered part of, this prospectus.

We will provide you without charge, upon your oral or written request, with an electronic or paper copy of any or all reports, proxy statements and other documents we file with the SEC, as well as any or all of the documents incorporated by reference in this prospectus (other than exhibits to such documents unless such exhibits are specifically incorporated by reference into such documents). Requests for such copies should be directed to:

25

Kintara Therapeutics, Inc.

Attn: Saiid Zarrabian, Chief Executive Officer

12707 High Bluff Dr., Suite 200

San Diego, CA 92130

(858) 350-4364

You should rely only on the information in this prospectus and the additional information described above and under the heading "Incorporation of Certain Information by Reference" below. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it. We are not making an offer to sell these securities in any jurisdiction where such offer or sale is not permitted. You should assume that the information in this prospectus was accurate on the date of the front cover of this prospectus only. Our business, financial condition, results of operations and prospects may have changed since that date.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to "incorporate by reference" information that we file with it into this prospectus, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. The information incorporated by reference is considered to be a part of this prospectus, and information that we file later with the SEC will automatically update and supersede information contained in this prospectus and any accompanying prospectus supplement.

We incorporate by reference the documents listed below that we have previously filed with the SEC:

All reports and other documents that we file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of the initial registration statement and prior to effectiveness of the registration statement, and after the date of this prospectus but before the termination of the offering of the securities hereunder will also be considered to be incorporated by reference into this prospectus from the date of the filing of these reports and documents, and will supersede the information herein; provided, however, that all reports, exhibits and other information that we "furnish" to the SEC will not be considered incorporated by reference into this prospectus. We undertake to provide without charge to each person (including any beneficial owner) who receives a copy of this prospectus, upon written or oral request, a copy of all of the preceding documents that are incorporated by reference (other than exhibits, unless the exhibits are specifically incorporated by reference into these documents). You may request a copy of these materials in the manner set forth under the heading "Additional Information," above.

26

KINTARA THERAPEUTICS, INC.

7,200,000 Shares of Common Stock

Pre-Funded Warrants to Purchase up to 4,800,000 Shares of Common Stock

Warrants to Purchase up to 12,000,000 Shares of Common Stock

Placement Agent Warrants to Purchase up to 600,000 Shares of Common Stock

Shares of Common Stock underlying the Pre-Funded Warrants, Warrants and Placement Agent Warrants

PROSPECTUS SUPPLEMENT

H.C. Wainwright & Co.

September 23, 2021

Please select the service you want to use:

• Newsvine
• Digg
• Delicious
• StumbleUpon
• Technorati
• Buzz
• Favorites
• Google Reader

Close

 Back

 View original format