Free Writing Prospectus (Form FWP)

Issuer Free Writing Prospectus

Filed Pursuant to Rule 433

Dated February 2, 2026

Relating to Prospectus dated April 8, 2025

Registration Statement No. 333-279692

Shares of Common Stock

Pre-Funded Warrants to Purchase Shares of Common Stock

This free writing prospectus relates only to the offering of shares of common stock and pre-funded warrants to purchase common stock described below by Perspective Therapeutics, Inc. ("we," "us," "our"," the "Company" and "Perspective"), and provides the terms of certain pre-funded warrants, and the shares of common stock issuable upon the exercise of such pre-funded warrants, being offered. Except as otherwise indicated, all information in this free writing prospectus assumes no exercise of outstanding options or warrants.

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RECENT DEVELOPMENTS

Based on information currently available, we estimate that as of December 31, 2025 we had approximately $144 million of cash, cash equivalents and short-term investments. The preliminary financial data included in this free writing prospectus has been prepared by, and are the responsibility of, our management. Our independent registered public accounting firm, WithumSmith+Brown, PC, has not audited, reviewed, compiled or performed any procedures with respect to the preliminary financial data. Accordingly, WithumSmith+Brown, PC does not express an opinion or any other form of assurance with respect thereto.

Further, as of December 31, 2025, we had approximately 74.3 million shares outstanding and approximately 10.9 million outstanding common stock warrants and options.

Our actual results as of December 31, 2025 may differ from the preliminary financial data due to the completion of our closing procedures with respect to the year ended December 31, 2025, final adjustments and other developments that may arise between now and the time the financial results for the fiscal year are finalized. Our consolidated audited financial statements as of and for the year ended December 31, 2025 will not be available until after this offering is completed.

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RISK FACTORS

Certain covenants related to our Investment Agreement with Lantheus may restrict our ability to obtain future financing and cause additional dilution for our stockholders.

Pursuant to that certain Investment Agreement, dated January 8, 2024, between Lantheus Alpha Therapy, LLC ("Lantheus") and us (the "Investment Agreement"), Lantheus was provided with certain pro rata participation rights to maintain its ownership position in us in the event that we make any public or non-public offering of any equity or voting interests in us or any securities that are convertible or exchangeable into (or exercisable for) equity or voting interests in us, subject to certain exceptions. These participation rights could severely impact our ability to engage investment bankers to structure a financing transaction and raise additional financing on favorable terms. Furthermore, negotiating and obtaining a waiver to these participation rights may either not be possible or may be costly to us. If Lantheus exercises its participation rights, our existing stockholders would be further diluted to the extent of the number of shares Lantheus acquires to maintain its ownership percentage. Lantheus has waived its participation rights in connection with this offering.

Pursuant to the Investment Agreement, we are required to notify Lantheus within 10 business days of the end of a fiscal quarter in which we issued shares of common stock pursuant to the Controlled Equity OfferingSM Sales Agreement, dated August 13, 2024, with Cantor Fitzgerald & Co. and RBC Capital Markets, LLC (the "Sales Agreement") of (i) the number of shares of common stock issued during such fiscal quarter pursuant to the Sales Agreement and (ii) the average price per share received by us before commissions (the "ATM Average Price"). Upon receipt of such notice, Lantheus may elect, at its option, to purchase all or a portion of its Pro Rata Portion (as defined in the Investment Agreement) of such shares at an aggregate price equal to the number of shares purchased multiplied by the ATM Average Price for such quarter (the "ATM Participation Right"). Pursuant to the Investment Agreement, Lantheus may not exercise the ATM Participation Right more than two times per calendar year.

You will experience immediate and substantial dilution if you purchase our securities in this offering.

Since the price per share of our common stock and the price per pre-funded warrant being offered is substantially higher than the net tangible book value per share of our common stock, you will suffer substantial dilution with respect to the securities you purchase in this offering. Our net tangible book value as of September 30, 2025 was approximately $192.2 million, or $2.59 per share of our common stock, based on 74,337,990 shares of our common stock outstanding on September 30, 2025.

In addition, as of September 30, 2025, we had outstanding options to purchase 10,486,831 shares of our common stock at a weighted-average exercise price of $4.97 per share and outstanding warrants to purchase 415,779 shares of our common stock at a weighted-average exercise price of $3.26 per share. As of September 30, 2025, there were 5,161,317 shares of our common stock available for future issuance under the 2020 Equity Plan. The shares of our common stock issuable under the 2020 Equity Plan may be immediately eligible for resale in the open market. Such shares of our common stock, along with any other market transactions, could adversely affect the market price of our common stock. Additional dilution may result from the issuance of shares of our common stock in connection with additional financings or in connection with commercial transactions.

Substantial future sales or other issuances of our common stock could depress the market for our common stock.

In the future, sales of a substantial number of shares of our common stock, or the perception by the market that those sales could occur, could cause the market price of our common stock to decline or could make it more difficult for us to raise funds through the sale of equity in the future.

In connection with this offering, we and our directors and executive officers have entered into lock-up agreements for a period of 60 days. We and our directors and executive officers may be released from such lock-up agreements prior to the expiration of the lock-up period at the discretion of Piper Sandler & Co. and UBS Securities, LLC. Upon expiration or earlier release of the lock-up, we and our directors and executive officers may sell shares into the market, which could adversely affect the market price of shares of our common stock.

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We have previously entered into the Sales Agreement, pursuant to which, from time to time, we may offer and sell shares of our common stock with an aggregate offering price of up to $250,000,000 under an "at-the-market" offering program. To the extent that we sell shares of our common stock pursuant to our at-the-market offering program or any similar program in the future, investors purchasing shares of common stock in this offering could experience further dilution.

In addition, certain of our employees, executive officers, and directors have entered or may enter into Rule 10b5-1 trading plans providing for sales of shares of our common stock from time to time. Under a Rule 10b5-1 trading plan, a broker executes trades pursuant to parameters established by the employee, director, or officer when entering into the plan, without further direction from the employee, officer, or director. A Rule 10b5-1 trading plan may be amended or terminated in some circumstances. Our employees, executive officers, and directors also may buy or sell additional shares outside of a Rule 10b5-1 trading plan when they are not in possession of material, nonpublic information, subject to the expiration of the lock-up agreements, if applicable.

In particular, during the lock-up period, our directors and officers may enter into any new plan established in compliance with Rule 10b5-1, provided that (i) such plan may only be established if no public announcement or filing with the SEC, or other applicable regulatory authority, is made (or required to be made) in connection with the establishment of such plan during such period, and (ii) no sale of shares of common stock are made pursuant to such plan during the lock-up period. Furthermore, the lock-up agreements also include other exceptions for shares sold by our executive officers and directors. Such sales of shares into the market, including during the lock-up period, could adversely affect the market price of shares of our common stock.

Future issuances of our common stock or our other equity securities could further depress the market for our common stock. We expect to continue to incur commercialization, drug development and selling, general and administrative costs, and to satisfy our funding requirements, we may need to sell additional equity securities. The sale or the proposed sale of substantial amounts of our common stock or our other equity securities may adversely affect the market price of our common stock and our stock price may decline substantially. Our stockholders may experience substantial dilution and a reduction in the price that they are able to obtain upon sale of their shares. New equity securities issued may have greater rights, preferences or privileges than our existing common stock.

We have broad discretion in the use of the net proceeds from this offering; despite our efforts, we may use such net proceeds in a manner that does not increase the value of your investment.

We currently intend to use the net proceeds from this offering to advance the clinical development of product candidates, continue to invest in our manufacturing facilities and for working capital and other general corporate purposes. A portion of the net proceeds may also be used to acquire, license or invest in complementary products, technologies, intellectual property or businesses, although we have no present commitments or agreements to do so. However, we have not determined the specific allocation of the net proceeds among these potential uses. Our management will have broad discretion over the use and investment of the net proceeds from this offering, and, accordingly, investors in this offering will need to rely upon the judgment of our management with respect to the use of proceeds, with only limited information concerning our specific intentions. These proceeds could be applied in ways that do not improve our operating results or increase the value of your investment.

We do not currently intend to pay dividends on our common stock, and any return to investors is expected to come, if at all, only from potential increases in the price of our common stock.

We have never declared or paid cash dividends on our capital stock, and you should not rely on an investment in our common stock to provide dividend income. We currently intend to retain all of our future earnings, if any, to finance the growth and development of our business and do not anticipate declaring or paying any cash dividends for the foreseeable future. As a result, capital appreciation, if any, of our common stock will be your sole source of gain for the foreseeable future.

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The trading price of the shares of our common stock could be highly volatile, and purchasers of our common stock could incur substantial losses.

The price of our common stock is highly volatile and may be affected by developments directly affecting our business, as well as by developments out of our control or not specific to us. The pharmaceutical and biotechnology industries, in particular, and the stock market generally, are vulnerable to abrupt changes in investor sentiment. Prices of securities and trading volumes of companies in the pharmaceutical and biotechnology industries, including ours, can swing dramatically in ways unrelated to, or that bear a disproportionate relationship to, our performance. This volatility may affect the price at which you could sell the shares of our common stock, and the sale of substantial amounts of our common stock could adversely affect the price of our common stock. Our stock price is likely to continue to be volatile and subject to significant price and volume fluctuations in response to market and other factors, including those described in the sections entitled "Risk Factors" in this free writing prospectus, the accompanying prospectus and the documents incorporated by reference therein.

As a result, you may not be able to sell your shares of common stock at or above the price at which you purchase them. In addition, the stock market in general, the NYSE American and the stock of pharmaceutical and bio pharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors may negatively affect the market price of our common stock, regardless of our actual operating performance.

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

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

Except for the right to participate in certain dividends and distributions, holders of the pre-funded warrants will have no rights as common stockholders until such holders exercise their pre-funded warrants and acquire our common stock.

Except by virtue of such holder's ownership of shares of our common stock, and except for the right to participate in certain dividends and distributions, until holders of the pre-funded warrants exercise their pre-funded warrants and acquire shares of our common stock, such holders will have no rights with respect to the shares of our common stock underlying such pre-funded warrants.

We may not receive any additional funds upon the exercise of the pre-funded warrants.

Each pre-funded warrant may be exercised by way of a cashless exercise, meaning that the holder may not pay a cash purchase price upon exercise, but instead would receive upon such exercise the net number of shares of our common stock determined according to the formula set forth in the pre-funded warrant. Accordingly, we may not receive any additional funds upon the exercise of the pre-funded warrants.

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Significant holders or beneficial holders of our common stock may not be permitted to exercise pre-funded warrants that they hold.

A holder of a pre-funded warrant will not be entitled to exercise any portion of any pre-funded warrant which, upon giving effect or immediately prior to such exercise, would cause (i) the aggregate number of shares of our common stock beneficially owned by such holder (together with its attribution parties) to exceed 4.99% or 9.99% (at the initial election of the holder) of the number of shares of our common stock outstanding immediately after giving effect to the exercise; or (ii) the combined voting power of our securities beneficially owned by such holder (together with its attribution parties) to exceed 4.99% or 9.99% (at the initial election of the holder) of the combined voting power of all of our securities outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. Such percentage may be increased by the holder of the pre-funded warrant to any other percentage not in excess of 19.99% of the issued and outstanding shares of our common stock immediately after giving effect to such issuance upon at least 61 days' prior notice from the holder to us. As a result, you may not be able to exercise your pre-funded warrants for shares of our common stock at a time when it would be financially beneficial for you to do so. In such circumstance you could seek to sell your pre-funded warrants to realize value, but you may be unable to do so in the absence of an established trading market for the pre-funded warrants.

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DESCRIPTION OF PRE-FUNDED WARRANTS

The following is a summary of certain terms and conditions of the pre-funded warrants being offered in this offering. The following description is subject in all respects to the provisions contained in the pre-funded warrants.

Form

The pre-funded warrants will be issued as individual warrant agreements to the purchasers. The form of pre-funded warrant will be filed as an exhibit to a Current Report on Form 8-K that we expect to file with the SEC.

Term

The pre-funded warrants will expire on the date the warrant is exercised in full.

Exercisability

The pre-funded warrants are exercisable at any time after their original issuance. 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 and by payment in full of the exercise price in immediately available funds for the number of shares of common stock purchased upon such exercise. As an alternative to payment in immediately available funds, the holder may, in its sole discretion, elect to exercise the pre-funded warrant through a cashless exercise, in which the holder would receive upon such exercise the net number of shares of our common stock determined according to the formula set forth in the pre-funded warrant. No fractional shares of our common stock will be issued in connection with the exercise of a pre-funded warrant. In lieu of fractional shares that would otherwise be issuable, the number of shares to be issued shall be rounded down to the next whole number and we will pay the holder an amount in cash equal to the fractional amount multiplied by the last closing trading price of our common stock on the exercise date.

Exercise Limitations

We may not effect the exercise of any pre-funded warrant, and a holder will not be entitled to exercise any portion of any pre-funded warrant that, upon giving effect to such exercise, would cause (i) the aggregate number of shares of our common stock beneficially owned by such holder (together with its attribution parties) to exceed 4.99% or 9.99% (at the initial election of the holder) of the number of shares of our common stock outstanding immediately after giving effect to the exercise; or (ii) the combined voting power of our securities beneficially owned by such holder (together with its attribution parties) to exceed 4.99% or 9.99% (at the initial election of the holder) of the combined voting power of all of our securities outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. However, any holder of a pre-funded warrant may increase or decrease such percentage to any other percentage not in excess of 19.99% upon at least 61 days' prior notice from the holder to us.

Exercise Price

The exercise price per whole share of our common stock purchasable upon the exercise of the pre-funded warrants is $0.001 per share of common stock. The exercise price of the pre-funded warrants and the number of shares of our common stock issuable upon exercise of the pre-funded warrants is subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock, as well as upon any distribution of assets, including cash, stock or other property, to our stockholders.

Transferability

Subject to applicable laws and the restrictions on transfer set forth in the pre-funded warrant, the pre-funded warrants may be offered for sale, sold, transferred or assigned without our consent.

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Exchange Listing

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 the listing of the pre-funded warrants on the NYSE American, any other national securities exchange or any other nationally recognized trading system.

Fundamental Transactions

Upon the consummation of a fundamental transaction (as described in the pre-funded warrants, and generally including any reorganization, recapitalization or reclassification of our common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of 50% of the voting power of our outstanding common stock), the holders of the pre-funded warrants will be entitled to receive, upon exercise of the pre-funded warrants, the kind and amount of securities, cash or other property that such holders would have received had they exercised the pre-funded warrants immediately prior to such fundamental transaction, without regard to any limitations on exercise contained in the pre-funded warrants (the "Alternate Consideration").

No Rights as a Stockholder

Except by virtue of such holder's ownership of shares of our common stock, and except for the right to participate in certain dividends and distributions, the holder of a pre-funded warrant does not have the rights or privileges of a holder of our common stock, including any voting rights, until such holder exercises the pre-funded warrant.

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MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES

The following discussion is a summary of the material U.S. federal income tax consequences of the purchase, ownership and disposition of shares of our common stock and pre-funded warrants issued pursuant to this offering, but does not purport to be a complete analysis of all potential tax effects. The effects of other U.S. federal tax laws, such as estate and gift tax laws, and any applicable state, local or non-U.S. tax laws are not discussed. This discussion is based on the Internal Revenue Code of 1986, as amended (the "Code"), Treasury Regulations promulgated thereunder, judicial decisions, and published rulings and administrative pronouncements of the U.S. Internal Revenue Service (the "IRS") in effect as of the date of this offering. These authorities may change or be subject to differing interpretations. Any such change or differing interpretation may be applied retroactively in a manner that could adversely affect a holder of our common stock or pre-funded warrants. We have not sought and do not intend to seek any rulings from the IRS regarding the matters discussed below. There can be no assurance the IRS or a court will not take a contrary position regarding the tax consequences of the purchase, ownership and disposition of our common stock or pre-funded warrants.

This discussion is limited to holders that hold our common stock or pre-funded warrants as a "capital asset" within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion does not address all U.S. federal income tax consequences relevant to a holder's particular circumstances, including the impact of any alternative minimum tax or the unearned income Medicare contribution tax. In addition, it does not address consequences relevant to holders subject to particular rules, including, without limitation:

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If a partnership (or other entity treated as a partnership for U.S. federal income tax purposes) holds our common stock or pre-funded warrants, the tax treatment of a partner in the partnership will depend on the status of the partner, the activities of the partnership and certain determinations made at the partner level. Accordingly, partnerships holding our common stock or pre-funded warrants and the partners in such partnerships should consult their tax advisors regarding the U.S. federal income tax consequences to them.

THIS DISCUSSION IS FOR INFORMATION PURPOSES ONLY AND IS NOT INTENDED AS TAX ADVICE. INVESTORS SHOULD CONSULT THEIR TAX ADVISORS WITH RESPECT TO THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AS WELL AS ANY TAX CONSEQUENCES OF THE PURCHASE, OWNERSHIP AND DISPOSITION OF OUR COMMON STOCK OR PRE-FUNDED WARRANTS ARISING UNDER THE U.S. FEDERAL ESTATE OR GIFT TAX LAWS OR UNDER THE LAWS OF ANY STATE, LOCAL OR NON-U.S. TAXING JURISDICTION OR UNDER ANY APPLICABLE INCOME TAX TREATY.

For purposes of this discussion, a "U.S. holder" is any beneficial owner of our common stock or pre-funded warrants that, for U.S. federal income tax purposes, is:

For purposes of this discussion, a "non-U.S. holder" is a beneficial owner of our common stock or pre-funded warrants that is neither a U.S. holder nor an entity treated as a partnership for U.S. federal income tax purposes.

General Treatment of Pre-Funded Warrants

Although the law in this area is not completely settled, the pre-funded warrants are generally expected to be treated as shares of our common stock for U.S. federal income tax purposes, in which case a holder of pre-funded warrants would generally be taxed in the same manner as a holder of common stock as described below. This position is not binding on the IRS, however, and the IRS may treat the pre-funded warrants as warrants to acquire our common stock and, if so, the amount and character of your gain with respect to an investment in our pre-funded warrants could change. You should discuss with your tax advisor the consequences of the purchase, ownership and disposition of the pre-funded warrants, as well as the exercise of, certain adjustments to, and any payments in respect of the pre-funded warrants (including potential alternative characterizations). The balance of this discussion generally assumes that the characterization of the pre-funded warrants as shares of our common stock described above is respected for U.S. federal income tax purposes.

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Tax Considerations Applicable to U.S. Holders

Distributions

We do not anticipate declaring or paying distributions to holders of our common stock in the foreseeable future. However, if we do make distributions on our common stock, those payments will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. To the extent those distributions (including constructive distributions) exceed both our current and our accumulated earnings and profits, the excess will constitute a return of capital and will first reduce a U.S. holder's basis in our common stock, but not below zero, and then will be treated as gain from the sale of stock as described below under the section entitled "Tax Considerations Applicable to U.S. Holders-Gain on Disposition of Common Stock or Pre-Funded Warrants." A preferential U.S. federal income tax rate may apply to any dividends paid to noncorporate U.S. holders meeting certain holding period requirements. Dividends received by a corporation may be eligible for a dividends received deduction, subject to applicable limitation.

The taxation of property received with respect to a pre-funded warrant on exercise other than common shares is unclear. It is possible such a receipt of property would be treated as a distribution on common stock as described in this section, although other treatments may also be possible. Investors should consult their tax advisors regarding the proper treatment of any such receipt of property in respect of the pre-funded warrants on exercise.

Gain on Disposition of Our Common Stock or Pre-Funded Warrants

Upon a sale or other taxable disposition of our common stock or pre-funded warrants, a U.S. holder generally will recognize capital gain or loss in an amount equal to the difference between the amount realized and the U.S. holder's adjusted tax basis in the common stock or pre-funded warrant. Capital gain or loss will constitute long-term capital gain or loss if such U.S. holder's holding period for the common stock or pre-funded warrant exceeds one year. Long-term capital gains derived by certain non-corporate U.S. holders, including individuals, are generally subject to taxation at preferential rates. The deductibility of capital losses is subject to certain limitations. U.S. holders who recognize losses with respect to a disposition of our common stock or pre-funded warrants should consult their own tax advisors regarding the tax treatment of such losses.

Exercise of Pre-Funded Warrants

A U.S. holder may exercise the pre-funded warrant by payment of exercise price or through a cashless exercise. The U.S. federal income tax treatment of a cashless exercise of pre-funded warrants into our common stock is unclear, and a U.S. holder should consult their own tax advisors regarding the U.S. federal income tax consequences of a cashless exercise of pre-funded warrants. In general, however, a U.S. holder should not recognize gain or loss for U.S. federal income tax purposes upon exercise of a pre-funded warrant pursuant to either method. If such U.S. holder receives a cash payment for a fractional share that would otherwise have been issuable upon exercise of the pre-funded warrant, the treatment of the receipt of such cash as either a distribution on common stock as described in the section above entitled "Tax Considerations Applicable to U.S. Holders-Distributions" or as a sale subject to the rules described above under the section entitled "Tax Considerations Applicable to U.S. Holders-Gain on Disposition of Our Common Stock or Pre-Funded Warrants" will depend on the circumstances as they exist at that time. The taxation of other property received with respect to a pre-funded warrant on exercise other than common shares is unclear. It is possible such a receipt of property would be treated as a distribution on common stock as described in the section above entitled "Tax Considerations Applicable to U.S. Holders-Distributions," although other treatments may also be possible. Investors should consult their tax advisors regarding the proper treatment of any such receipt of cash or other property in respect of the pre-funded warrants on exercise.

A U.S. holder's initial tax basis in the share of common stock received upon exercise of the pre-funded warrant generally should be equal to the sum of (i) such U.S. holder's tax basis in the pre-funded warrant and (ii) the exercise price paid or treated as paid by such U.S. holder on the exercise of the pre-funded warrant. A U.S. holder's holding period in the common stock received upon exercise generally should include such U.S. holder's holding period in the pre-funded warrants exchanged therefor.

Certain Adjustments to the Pre-Funded Warrants

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Under Section 305 of the Code, an adjustment to the number of shares of common stock that will be issued on the exercise of the pre-funded warrants, or an adjustment to the exercise price of the pre-funded warrants, may be treated as a constructive distribution to a U.S. holder of pre-funded warrants if, and to the extent that, such adjustment has the effect of increasing such U.S. holder's proportionate interest in our "earnings and profits" or assets, depending on the circumstances of such adjustment (for example, if such adjustment is to compensate for a distribution of cash or other property to our shareholders).

U.S. holders are encouraged to consult their own tax advisors regarding the application of Section 305 of the Code to the pre-funded warrants.

Information Reporting and Backup Withholding

Information reporting requirements generally will apply to payments of dividends (including constructive dividends) on the common stock or pre-funded warrants and to the proceeds of a sale or other disposition of common stock or pre-funded warrants paid by us to you unless you are an exempt recipient, such as certain corporations. Backup withholding will apply to those payments if a U.S. holder fails to provide their taxpayer identification number, or certification of exempt status, or if a U.S. holder otherwise fails to comply with applicable requirements to establish an exemption.

Backup withholding is not an additional tax. Rather, any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a U.S. holder's U.S. federal income tax liability, if any, provided the required information is timely furnished to the IRS. Investors should consult their own tax advisors regarding their qualification for exemption from information reporting and backup withholding and the procedure for obtaining such exemption.

Tax Considerations Applicable to Non-U.S. Holders

Distributions

We do not anticipate declaring or paying distributions to holders of our common stock in the foreseeable future. However, if we do make distributions on our common stock, such distributions of cash or property (including constructive distributions) will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Amounts not treated as dividends for U.S. federal income tax purposes will constitute a return of capital and first be applied against and reduce a non-U.S. holder's adjusted tax basis in its common stock, but not below zero. Any excess will be treated as capital gain and will be treated as described below under the section entitled "Sale or Other Disposition of Common Stock or Pre-Funded Warrants." Because we may not know the extent to which a distribution is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of the withholding rules discussed below we or the applicable withholding agent may treat the entire distribution as a dividend.

Subject to the discussion below on backup withholding and Sections 1471 to 1474 of the Code (such Sections commonly referred to as the Foreign Account Tax Compliance Act or "FATCA"), dividends paid to a non-U.S. holder of our common stock that are not effectively connected with the non-U.S. holder's conduct of a trade or business within the U.S. will be subject to U.S. federal withholding tax at a rate of 30% of the gross amount of the dividends (or such lower rate specified by an applicable income tax treaty).

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Non-U.S. holders may be entitled to a reduction in or an exemption from withholding on dividends as a result of either (a) an applicable income tax treaty or (b) the non-U.S. holder holding our common stock in connection with the conduct of a trade or business within the U.S. and dividends being effectively connected with that trade or business. To claim such a reduction in or exemption from withholding, the non-U.S. holder must provide the applicable withholding agent with a properly executed (a) IRS Form W-8BEN or W-8BEN-E (or other applicable documentation) claiming an exemption from or reduction of the withholding tax under the benefit of an income tax treaty between the U.S. and the country in which the non-U.S. holder resides or is established, or (b) IRS Form W-8ECI stating that the dividends are not subject to withholding tax because they are effectively connected with the conduct by the non-U.S. holder of a trade or business within the U.S., as may be applicable. These certifications must be provided to the applicable withholding agent prior to the payment of dividends and must be updated periodically. Non-U.S. holders that do not timely provide the applicable withholding agent with the required certification, but that qualify for a reduced rate under an applicable income tax treaty, may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS.

If dividends paid to a non-U.S. holder are effectively connected with the non-U.S. holder's conduct of a trade or business within the U.S. (and, if required by an applicable income tax treaty, the non-U.S. holder maintains a permanent establishment in the U.S. to which such dividends are attributable), then, although exempt from U.S. federal withholding tax (provided the non-U.S. holder provides appropriate certification, as described above), the non-U.S. holder will be subject to U.S. federal income tax on such dividends on a net income basis at the regular graduated U.S. federal income tax rates. In addition, a non-U.S. holder that is a corporation may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on its effectively connected earnings and profits for the taxable year that are attributable to such dividends, as adjusted for certain items. Non-U.S. holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty.

The taxation of property received with respect to a pre-funded warrant on exercise other than common shares is unclear. It is possible such a receipt of property would be treated as a distribution as described in this section, although other treatments may also be possible. Investors should consult their tax advisors regarding the proper treatment of any such receipt of property in respect of the pre-funded warrants on exercise.

Sale or Other Disposition of Common Stock or Pre-Funded Warrants

Subject to the discussions below on backup withholding and FATCA, a non-U.S. holder will not be subject to U.S. federal income tax on any gain realized upon the sale or other disposition of our common stock or pre-funded warrants unless:

Gain described in the first bullet point above will generally be subject to U.S. federal income tax on a net income basis at the regular graduated U.S. federal income tax rates. A non-U.S. holder that is a foreign corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected gain, as adjusted for certain items.

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A non-U.S. holder described in the second bullet point above will be subject to U.S. federal income tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on any gain derived from the disposition, which may be offset by certain U.S. source capital losses of the non-U.S. holder (even though the individual is not considered a resident of the U.S.) provided the non-U.S. holder has timely filed U.S. federal income tax returns with respect to such losses.

With respect to the third bullet point above, we believe we are not currently and do not anticipate becoming a USRPHC. Because the determination of whether we are a USRPHC depends on the fair market value of our USRPIs relative to the fair market value of our other business assets and our non-U.S. real property interests, however, there can be no assurance we are not a USRPHC or will not become one in the future. Even if we are or were to become a USRPHC, gain arising from the sale or other taxable disposition by a non-U.S. holder of our common stock will not be subject to U.S. federal income tax if our common stock is "regularly traded," as defined by applicable Treasury Regulations, on an established securities market such as the NYSE American, and such non-U.S. holder owned, actually and constructively, 5% or less of our common stock throughout the shorter of the five-year period ending on the date of the sale or other taxable disposition or the non-U.S. Holder's holding period. Special rules may apply to non-U.S. holders of pre-funded warrants, who should consult their tax advisors.

Non-U.S. holders should consult their tax advisors regarding potentially applicable income tax treaties that may provide for different rules than those described above.

Exercise of Pre-Funded Warrants

A non-U.S. holder may exercise the pre-funded warrant by payment of the exercise price or through a cashless exercise. The U.S. federal income tax treatment of a cashless exercise of pre-funded warrants into our common stock is unclear, and non-U.S. holders should consult their own tax advisors regarding the U.S. federal income tax consequences of a cashless exercise of pre-funded warrants. In general, however, a non-U.S. holder should not recognize gain or loss for U.S. federal income tax purposes upon exercise of a pre-funded warrant pursuant to either method. If such non-U.S. holder receives a cash payment for a fractional share that would otherwise have been issuable upon exercise of the pre-funded warrant, the treatment of the receipt of such cash as either a distribution on common stock as described in the section above entitled "Tax Considerations Applicable to Non-U.S. Holders-Distributions" or as a sale subject to the rules described above under the section entitled "Tax Considerations Applicable to Non-U.S. Holders-Sale or Other Disposition of Common Stock or Pre-Funded Warrants" will depend on the circumstances as they exist at that time. The taxation of other property received with respect to a pre-funded warrant on exercise other than common shares is unclear. It is possible such a receipt of property would be treated as a distribution on common stock as described in the section above entitled "Tax Considerations Applicable to Non-U.S. Holders-Distributions," although other treatments may also be possible. Investors should consult their tax advisors regarding the proper treatment of any such receipt of cash or other property in respect of the pre-funded warrants on exercise.

Certain Adjustments to the Pre-Funded Warrants

Under Section 305 of the Code, an adjustment to the number of shares of common stock that will be issued on the exercise of the pre-funded warrants, or an adjustment to the exercise price of the pre-funded warrants, may be treated as a constructive distribution to a non-U.S. holder of the pre-funded warrants if, and to the extent that, such adjustment has the effect of increasing such non-U.S. holder's proportionate interest in our "earnings and profits" or assets, depending on the circumstances of such adjustment (for example, if such adjustment is to compensate for a distribution of cash or other property to our shareholders).

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In addition, regulations governing "dividend equivalents" under Section 871(m) of the Code may apply to the pre-funded warrants. Under those regulations, an implicit or explicit payment under the pre-funded warrants that references a dividend distribution on our common stock would generally be taxable to a non-U.S. holder as described under "Distributions" above. Such dividend equivalent amount would be taxable and subject to withholding whether or not there is actual payment of cash or other property, and we may satisfy any withholding obligations we have in respect of the pre-funded warrants by withholding from other amounts due to a non-U.S. holder.

Non-U.S. holders are encouraged to consult their own tax advisors regarding the application of Sections 305 and 871(m) of the Code to the pre-funded warrants.

Information Reporting and Backup Withholding

Subject to the discussion below on foreign accounts, a non-U.S. holder will not be subject to backup withholding with respect to distributions we make on our common stock or pre-funded warrants to the non-U.S. holder, provided the applicable withholding agent does not have actual knowledge or reason to know such holder is a U.S. person and the holder certifies its non-U.S. status, such as by providing a valid IRS Form W-8BEN, W-8BEN-E or W-8ECI, or other applicable certification. However, information returns generally will be filed with the IRS in connection with any distributions (including deemed distributions) made on our common stock or pre-funded warrants to a non-U.S. holder, regardless of whether any tax was actually withheld. Copies of these information returns may also be made available under the provisions of a specific treaty or agreement to the tax authorities of the country in which the non-U.S. holder resides or is established.

Information reporting and backup withholding may apply to the proceeds of a sale or other taxable disposition of our common stock or pre-funded warrants within the U.S., and information reporting may (although backup withholding generally will not) apply to the proceeds of a sale or other taxable disposition of our common stock or pre-funded warrants outside the U.S. conducted through certain U.S.-related financial intermediaries, in each case, unless the beneficial owner certifies under penalty of perjury that it is a non-U.S. holder on IRS Form W-8BEN or W-8BEN-E, or other applicable form (and the payor does not have actual knowledge or reason to know that the beneficial owner is a U.S. person) or such owner otherwise establishes an exemption. Proceeds of a disposition of our common stock or pre-funded warrants conducted through a non-U.S. office of a non-U.S. broker generally will not be subject to backup withholding or information reporting. Non-U.S. holders should consult their tax advisors regarding the application of the information reporting and backup withholding rules to them.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a non-U.S. holder's U.S. federal income tax liability, provided the required information is timely furnished to the IRS.

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Additional Withholding Tax on Payments Made to Foreign Accounts

Withholding taxes may be imposed under FATCA on certain types of payments made to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends (including deemed dividends) paid on our common stock or pre-funded warrants, to a "foreign financial institution" or a "non-financial foreign entity" (each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any "substantial United States owners" (as defined in the Code) or furnishes identifying information regarding each substantial U.S. owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. Because we may not know the extent to which a distribution is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of these withholding rules we or the applicable withholding agent may treat the entire distribution as a dividend. While withholding under FATCA would have applied also to payments of gross proceeds from the sale or other disposition of stock on or after January 1, 2019, proposed Treasury Regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued. Prospective investors should consult their tax advisors regarding the potential application of these withholding provisions, including the proposed Treasury Regulations. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the U.S. governing FATCA may be subject to different rules.

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Perspective Therapeutics, Inc. has filed a registration statement (and the accompanying base prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the base prospectus and other documents the Company has filed with the SEC for more complete information about the Company and the offering. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, copies may be obtained from: Piper Sandler & Co., Attention: Prospectus Department, 350 North 5th Street, Suite 1000, Minneapolis, Minnesota 55401 or by email at [email protected]; UBS Securities LLC, 11 Madison Avenue New York, New York 10010, Attention: Prospectus Department, by calling 1-833-481-0269 or by e-mail at [email protected]; Oppenheimer & Co. Inc., Attention: Syndicate Prospectus Department, 85 Broad Street, 26th Floor, New York, New York 10004, by calling 1-212-667-8055 or by email at [email protected]; Truist Securities, Inc., Attention: Prospectus Department, 740 Battery Avenue SE, 3rd Floor, Atlanta, Georgia 30339 or by calling 1-800-685-4786 or by email at [email protected]; or LifeSci Capital LLC at 1700 Broadway, 40th Floor, New York, New York 10019 or by email at [email protected].

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