Perspective Therapeutics, Inc.

Previous wording

You should read the following discussion and analysis of our financial condition and results of operations together with (i) the unaudited condensed consolidated financial statements and the notes thereto included elsewhere in this Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 (Form 10-Q), (ii) our audited consolidated financial statements and notes thereto contained in our Annual Report on Form 10-K for the year ended December 31, 2024 filed with the Securities and Exchange Commission (SEC) on March 26, 2025 and amended on March 28, 2025 (2024 Form 10-K) and (iii) other filings we have made with the SEC. As discussed under the heading “Cautionary Note Regarding Forward-Looking Statements,” this discussion contains forward-looking statements that reflect our plans, estimates and beliefs, and involves numerous risks and uncertainties, including but not limited to those described under the heading “Risk Factors” in the 2024 Form 10-K that may cause actual results to differ materially from those described in or implied by any forward-looking statements. Unless the context otherwise requires, references in these notes to the “Company,” “Perspective,” “we,” “us” and “our,” except where the context requires otherwise, refer to Perspective Therapeutics, Inc. and its subsidiaries. References to “Isoray” refer to Isoray Medical, Inc., a wholly owned subsidiary.

Current wording

You should read the following discussion and analysis of our financial condition and results of operations together with (i) the unaudited condensed consolidated financial statements and the notes thereto included elsewhere in this Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 (Form 10-Q), (ii) our audited consolidated financial statements and notes thereto contained in our Annual Report on Form 10-K for the year ended December 31, 2025 filed with the Securities and Exchange Commission (SEC) on March 16, 2026 (2025 Form 10-K) and (iii) other filings we have made with the SEC. As discussed under the heading “Cautionary Note Regarding Forward-Looking Statements,” this discussion contains forward-looking statements that reflect our plans, estimates and beliefs, and involves numerous risks and uncertainties, including but not limited to those described under the heading “Risk Factors” in the 2025 Form 10-K that may cause actual results to differ materially from those described in or implied by any forward-looking statements. Unless the context otherwise requires, references in these notes to the “Company,” “Perspective,” “we,” “us” and “our,” except where the context requires otherwise, refer to Perspective Therapeutics, Inc. and its subsidiaries.

Previous wording

We are a radiopharmaceutical development company that is pioneering advanced treatment applications for cancers throughout the body. We have proprietary technology that utilizes the alpha-emitting isotope Lead-212 (212 Pb) to deliver powerful radiation specifically to cancer cells via specialized targeting moieties. We are also developing complementary imaging diagnostics that incorporate the same targeting moieties, which provides the opportunity to personalize treatment and optimizes patient outcomes. This theranostic approach enables the ability to see the specific tumor and then treat it to potentially improve efficacy and minimize toxicity.

Current wording

We are a radiopharmaceutical development company pioneering advanced treatments for cancers throughout the body. We have proprietary technology that utilizes the alpha-emitting isotope Lead-212 (212 Pb) to deliver powerful radiation specifically to cancer cells via specialized targeting moieties. We are also developing complementary imaging diagnostics that incorporate the same targeting moieties, which provides the opportunity to personalize treatment and optimize patient outcomes. This theranostic approach enables the ability to see the specific tumor and then treat it to potentially improve efficacy and minimize toxicity.

Previous wording

We initially dosed two patients in Cohort 1 (treated at 2.5 mCi per dose) and seven patients in Cohort 2 (treated at 5.0 mCi per dose) of our Phase 1/2a study of [212 Pb]VMT-α-NET in patients with unresectable or metastatic SSTR2-expressing NETs, regardless of body weight. Subsequent review for dose-limiting toxicity (DLT) during the safety observation period in these seven patients in Cohort 2 by the Safety Monitoring Committee (SMC) led the SMC to recommend escalating further in a third cohort and enrolling additional patients at 5 mCi to better understand efficacy and safety. During the second quarter of 2025, enrollment for Cohort 2 closed with an additional 39 patients having received at least one treatment, for a total of 46 patients including the seven who were enrolled for DLT observation. As of October 31, 2025, a total of 35 patients in Cohort 2 would have had the opportunity for at least 32 weeks of follow up since beginning treatment, which is sufficient time for them to have completed at least one scan following the full course of treatment. In late June 2025, we announced the opening of Cohort 3 in which patients will receive up to four fixed administered doses of [212 Pb]VMT-α-NET at 6 mCi every eight weeks if they weigh more than 60 kg (133 lb), or 100μCi/kg of body weight if they weigh less than or equal to 60 kg. As of September 30, 2025, eight Cohort 3 patients have commenced treatment with VMT-α-NET and will contribute to DLT observation for this dose level. We are evaluating whether to add additional patients to this cohort or explore alternative dose regimens before nominating a dose for a registration enabling study. We plan to submit to medical conferences relevant updates on patients dosed to date who have had the opportunity to receive at least one scan after their full treatment (up to four doses every eight weeks) for presentation in the next 12 months.

Current wording

We initially dosed two patients in Cohort 1 (treated at 2.5 mCi per dose) and seven patients in Cohort 2 (treated at 5.0 mCi per dose) of our Phase 1/2a clinical trial (NCT05636618) of [212 Pb]VMT-α-NET in patients with unresectable or metastatic SSTR2-expressing NETs, regardless of body weight. Subsequent review for dose-limiting toxicity (DLT) during the safety observation period in the seven patients enrolled in Cohort 2 by the Safety Monitoring Committee (SMC) led the SMC to recommend escalating further in a third cohort and enrolling additional patients at 5.0 mCi to better understand efficacy and safety. During the second quarter of 2025, enrollment for Cohort 2 closed with an additional 39 patients having received at least one treatment, for a total of 46 patients including the seven who were enrolled for DLT observation.

Previous wording

We are also leveraging our TAT platform with our second program candidate, VMT01, which is currently in Phase 1/2a clinical trials. We designed VMT01 to target and deliver 212 Pb to tumor sites expressing melanocortin 1 receptor (MC1R), a protein that is overexpressed in melanoma cancers. [212 Pb]VMT01 is a TAT in development for second-line or later treatment of patients with progressive MC1R-positive metastatic melanoma.

Current wording

We are also leveraging our TAT platform with our product candidate, VMT01, which is currently in Phase 1/2a clinical trials. We designed VMT01 to target and deliver 212 Pb to tumor sites expressing melanocortin 1 receptor (MC1R), a protein that is overexpressed in melanoma cancers. [212 Pb]VMT01 is a TAT in development for second-line or later treatment of patients with progressive MC1R-positive metastatic melanoma.

Previous wording

In preclinical experiments, [212 Pb]VMT01 demonstrated efficacy via two distinct mechanisms of action: direct cell killing at high radiation doses and through immunostimulatory low-dose induction of immune-mediated cell death. Efficacy was augmented by immune checkpoint inhibitors. In September 2024, we announced that on the basis of these results, the FDA granted Fast Track Designation for the clinical development of [212 Pb]VMT01. This study is a multi-center, open-label dose escalation, dose expansion study (clinicaltrials.gov identifier NCT05655312) in patients with histologically confirmed melanoma and MC1R-positive imaging scans. Patients were required to have already received standard of care. Eligible patients may receive up to three treatments with [212 Pb]VMT01, eight weeks apart.

Current wording

In preclinical experiments [212 Pb]VMT01 demonstrated efficacy via two distinct mechanisms of action: direct cell killing at high radiation doses and through immunostimulatory low-dose induction of immune-mediated cell death. Efficacy was augmented by immune checkpoint inhibitors. In September 2024, we announced that on the basis of these results, the U.S. Food and Drug Administration (FDA) granted Fast Track Designation for the clinical development of [212 Pb]VMT01. This study is a multi-center, open-label dose escalation, dose expansion study (clinicaltrials.gov identifier NCT05655312) in patients with histologically confirmed melanoma and MC1R-positive imaging scans. Patients were required to have already received standard of care. Eligible patients may receive up to three treatments with [212 Pb]VMT01, eight weeks apart.

Previous wording

In October 2024, we announced initial results from the first two dosing cohorts. Three patients were enrolled in Cohort 1 (who received 3 mCi of [212 Pb]VMT01), while seven patients were enrolled in Cohort 2 (who received 5 mCi of [212 Pb]VMT01). Patients in each cohort received a median of five prior lines of systematic therapy, including a median of three prior lines of immunotherapy. No DLTs were observed among any patients, and no AEs led to treatment discontinuation. Treatment emergent AEs were mostly grades 1 and 2. None of the four cases of grade 3 treatment emergent AEs were deemed to be treatment related. There were no grade 4 or 5 treatment emergent AEs. No renal toxicities had been reported as of October 11, 2024 (there were no clinically significant changes in blood urea nitrogen or serum creatinine) in spite of dosimetry estimated renal radiation that approached the higher end of conventional dosing.

Current wording

In October 2024, we announced initial results from the first two dosing cohorts. Three patients were enrolled in Cohort 1 and received 3 mCi of [212 Pb]VMT01, while seven patients were enrolled in Cohort 2 and received 5 mCi of [212 Pb]VMT01. Patients in each cohort received a median of five prior lines of systematic therapy, including a median of three prior lines of immunotherapy. No DLTs were observed among any patients, and no adverse events (AEs) led to treatment discontinuation. Treatment emergent AEs were mostly grades 1 and 2. None of the four cases of grade 3 treatment emergent AEs were deemed to be treatment related. There were no grade 4 or 5 treatment emergent AEs. No renal toxicities had been reported as of October 11, 2024 (there were no clinically significant changes in blood urea nitrogen or serum creatinine) in spite of dosimetry estimated renal radiation that approached the higher end of conventional dosing.

Previous wording

The SMC reviewed these findings and recommended exploring a lower dose level of 1.5 mCi per dose, both as a single agent and in combination with the anti-PD-1 antibody, nivolumab. The SMC’s recommendation allows for the monotherapy and combination cohorts to proceed concurrently. An amendment to further explore lower dose levels for monotherapy was approved, and Cohort 3 at 1.5 mCi per dose was opened for enrollment. The combination cohort at 1.5 mCi per dose with nivolumab was also opened for enrollment. The first patients in the combination and monotherapy cohorts received their first treatments in March and April 2025, respectively. As of July 31, 2025, a total of five patients had received their initial monotherapy treatments of VMT01 at 1.5 mCi per dose, once every eight weeks for up to three doses. Additionally, two patients had received VMT01 1.5 mCi with nivolumab. Both cohorts remain open for enrollment.

Current wording

The SMC reviewed these findings and recommended exploring a lower dose level of 1.5 mCi per dose, both as a single agent and in combination with the anti-PD-1 antibody, nivolumab. The SMC’s recommendation would allow for the monotherapy and combination cohorts to proceed concurrently. An amendment to further explore lower dose levels for monotherapy was approved, and Cohort 3 at 1.5 mCi per dose was opened for enrollment. The combination cohort at 1.5 mCi per dose with nivolumab was also opened for enrollment. The first patients in the combination and monotherapy cohorts received their first treatments in March and April 2025, respectively. As of July 31, 2025, a total of five patients had received their initial monotherapy treatments of VMT01 at 1.5 mCi per dose, once every eight weeks for up to three doses. Additionally, two patients had received VMT01 1.5 mCi with nivolumab. Both cohorts are now closed for enrollment.

Previous wording

Since then, five patients had received VMT01 treatment as of October 31, 2025. Three patients received VMT01 at 3.0 mCi in combination with nivolumab. Two patients had received 3.0 mCi of VMT01 as monotherapy, in addition to the three patients who received this monotherapy dose in late 2023.

Current wording

As of February 28, 2026, a total of 10 patients had received VMT01 treatment following the re-opening of the [212 Pb]VMT01 3.0 mCi monotherapy cohort and the opening of the cohort in which patients are receiving [212 Pb]VMT01 at 3.0 mCi in combination with nivolumab. Six patients had received VMT01 at 3.0 mCi in combination with nivolumab. Four patients had received 3.0 mCi of VMT01 as monotherapy, in addition to the three patients who received this monotherapy dose in late 2023. Both cohorts are now closed for enrollment.

Previous wording

We plan to submit to medical conferences data on each cohort after all patients in the cohort have had the opportunity for at least 24 weeks of follow up after their initial doses, which is sufficient time to receive at least one scan after their full treatment (up to three doses every eight weeks), if they receive all three doses of treatment per protocol.

Current wording

By late 2026, the 10 patients who had received VMT01 3.0 mCi treatment since the initiation or re-opening of these cohorts in September 2025 have had the opportunity for at least 24 weeks of follow-up after their initial doses, sufficient time to receive at least one scan after their full treatment (up to three doses every eight weeks).

Previous wording

Preclinical results for PSV359 were presented during the Society of Nuclear Medicine and Molecular Imaging and European Association of Nuclear Medicine annual meetings in June and October 2024, respectively. The purpose of this study was to evaluate the in vitro and in vivo performance of [203/212 Pb]PSV359 in preclinical xenograft models. Overall, strong anti-tumor clinical activity of [212 Pb]PSV359 was found in both HT1080-human FAP-α (FAP-α on cancer cells) and U87MG (FAP-α in stromal tissues) xenograft models.

Current wording

Preclinical results for PSV359 were presented during the Society of Nuclear Medicine and Molecular Imaging 2024 Annual Meeting and the 37th Annual Congress of the European Association of Nuclear Medicine meetings in June and October 2024, respectively. Researchers presented a novel cyclic peptide targeting human FAP-α, which was discovered by us via phage display methods. FAP-α is a protein abundantly expressed in certain cancer cells as well as cancer-associated fibroblasts in tumor lesions and involved in promoting disease progression. The peptide was conjugated to a lead (Pb)-specific chelator via a molecular linker to form a novel construct, PSV359. The purpose of this study was to evaluate the in vitro and in vivo performance of [203/212 Pb]PSV359 in preclinical xenograft models. Overall, strong anti-tumor clinical activity of [212 Pb]PSV359 was found in both HT1080-human FAP-α (FAP-α on cancer cells) and U87MG (FAP-α in stromal tissues) xenograft models.

Previous wording

We filed an IND application for PSV359 in December 2024, and we received a “study may proceed” letter (i.e., approval to conduct the trial) from the FDA in the first quarter of 2025. In April 2025, we announced the first patient was treated with [212 Pb]PSV359. As of October 31, 2025, two patients have been treated with [212 Pb]PSV359 at 2.5 mCi (Cohort 1) and one patient has been treated with [212 Pb]PSV359 at 5.0 mCi (Cohort 2), for a total of three patients. Activation activities are underway for additional sites.

Current wording

We filed an IND application for PSV359 in December 2024, and we received a “study may proceed” letter (i.e., approval to conduct the trial) from the FDA in the first quarter of 2025. In April 2025, we announced the first patient was treated with [212 Pb]PSV359. As of April 30, 2026, two patients have been treated with [212 Pb]PSV359 at 2.5 mCi (Cohort 1), and seven patients have been treated with [212 Pb]PSV359 at 5.0 mCi (Cohort 2), for a total of nine patients. By late 2026, these patients will have had the opportunity for at least 32 weeks of follow-up after their initial doses, sufficient time to have completed at least one scan after the full course of treatment (up to four doses every eight weeks).

Previous wording

Our discovery team is preparing multiple additional novel constructs for potential first-in-human imaging as a de-risking step for potential therapeutic benefit, including our pre-targeting platform license from Stony Brook University. If and when these constructs meet our criteria for further development, we plan to proceed with pre-IND filing activities.

Current wording

Our discovery team is preparing multiple additional novel constructs for potential first-in-human (FIH) imaging as a de-risking step for potential therapeutic benefit, including our pre-targeting platform license from Stony Brook University. If and when these constructs meet our criteria for further development, we plan to proceed with pre-IND filing activities.

Previous wording

We have had recurring losses since inception. We expect our expenses to increase in connection with our ongoing activities, particularly as we advance and expand preclinical activities, clinical trials and potential commercialization of our program candidates. Our costs are also expected to increase as we:

Current wording

We have had recurring losses since inception. We expect our expenses to increase in connection with our ongoing activities, particularly as we advance and expand preclinical activities, clinical trials and potential commercialization of our product candidates. Our costs are also expected to increase as we:

Previous wording

continue to initiate and progress other supporting studies required for regulatory approval of our program candidates;

Current wording

continue to initiate and progress other supporting studies required for regulatory approval of our product candidates;

Previous wording

initiate preclinical studies and clinical trials for any additional indications for our current program candidates and any future program candidates that we may pursue;

Current wording

initiate preclinical studies and clinical trials for any additional indications for our current product candidates and any future product candidates that we may pursue;

Previous wording

continue to build our portfolio of program candidates through the acquisition or in-license of additional program candidates or technologies;

Current wording

continue to build our portfolio of product candidates through the acquisition or in-license of additional product candidates or technologies;

Previous wording

pursue regulatory approvals for our current and future program candidates that successfully complete clinical trials;

Current wording

pursue regulatory approvals for our current and future product candidates that successfully complete clinical trials;

Previous wording

support our marketing and distribution infrastructure to commercialize any future program candidates for which we may obtain marketing approval; and

Current wording

support our marketing and distribution infrastructure to commercialize any future product candidates for which we may obtain marketing approval; and

Previous wording

As of September 30, 2025, we had cash, cash equivalents and short-term investments of $174.1 million. We believe our cash, cash equivalents and short-term investments will be sufficient to fund our current planned clinical milestones and operational investments for at least the next 12 months from the date the condensed consolidated financial statements in this report were issued and into late 2026. Monthly operating expenses are budgeted to increase for research and development and general and administrative expenses as management works to implement its strategy to advance our clinical assets in their clinical trials and to progress our preclinical assets towards clinical trials. Management anticipates a significant increase in expenses, particularly in research and development, as we undertake these activities.

Current wording

As of March 31, 2026, we had cash, cash equivalents and short-term investments of $270.9 million. We believe our cash, cash equivalents and short-term investments will be sufficient to fund our current planned clinical milestones and operational investments for at least the next 12 months from the date the condensed consolidated financial statements in this report were issued and into late 2027. Management anticipates a significant increase in expenses, particularly in research and development, as it works to implement its strategy to advance our clinical assets in their clinical trials, expand our manufacturing capabilities and progress our preclinical assets towards clinical trials.

Previous wording

In May 2025, we entered into a purchase order with the U.S. Department of Energy (DOE) under which we will purchase thorium-228 from the DOE during 2025 and 2026. The purchase order includes a “take-or-pay” provision pursuant to which we are committed to purchasing approximately $8.4 million of thorium-228 during the term of the agreement.

Current wording

In May 2025 and May 2026, we entered into supply agreements with the U.S. Department of Energy (DOE) under which we will purchase Thorium-228 from the DOE between 2025 and 2027. As of March 31, 2026, we have met and been invoiced for our minimum purchase requirements under the May 2025 supply agreement. The May 2026 supply agreement includes a “take-or-pay” provision pursuant to which we are committed to purchasing approximately $9.9 million of Thorium-228 during the term of the agreement.

Previous wording

In 2024, we entered into a Master Equipment and Services Agreement (MESA) and statements of work (SOWs) thereunder with Comecer SpA (Comecer), pursuant to which we agreed to purchase from Comecer manufacturing equipment for the production of our radiopharmaceutical program candidates including, but not limited to, isotope processing hot cells and production suites and related equipment (collectively, the Deliverables) and services for installation and validation of the Deliverables at several of our production facilities in the United States. The aggregate consideration for such equipment and services pursuant to the MESA and SOWs is approximately €49.0 million payable in cash, excluding certain incidental costs, such as taxes, customs and duties, local transport, insurance and rigging. We may also elect to purchase certain additional equipment and services pursuant to the SOWs. The MESA provides for the payment of certain amounts in installments over the course of the production, installation and validation of the Deliverables. For additional information, see Note 7, Property and Equipment, of the 2024 Form 10-K.

Current wording

In 2024, we entered into a Master Equipment and Services Agreement (MESA) and statements of work (SOWs) thereunder with Comecer SpA (Comecer), pursuant to which we agreed to purchase from Comecer manufacturing equipment for the production of our radiopharmaceutical program candidates including, but not limited to, isotope processing hot cells and production suites and related equipment (collectively, the Deliverables) and services for installation and validation of the Deliverables at several of our production facilities in the United States. The aggregate consideration for such equipment and services pursuant to the MESA and SOWs is approximately €49.0 million payable in cash, excluding certain incidental costs, such as taxes, customs and duties, local transport, insurance and rigging. We may also elect to purchase certain additional equipment and services pursuant to the SOWs. The MESA provides for the payment of certain amounts in installments over the course of the production, installation and validation of the Deliverables.

Previous wording

In 2024, we purchased buildings located in the metropolitan areas of Houston, TX, Chicago, IL, and Los Angeles, CA, which we intend to use for the manufacture of our program candidates upon completion of modifications and installation of equipment.

Current wording

In 2024, we purchased buildings located in the metropolitan areas of Houston, TX, Chicago, IL, and Los Angeles, CA, which we intend to use for the manufacture of our product candidates upon completion of modifications and installation of equipment.

Previous wording

Also in 2024, we acquired the assets and associated lease of Lantheus’ radiopharmaceutical manufacturing facility in Somerset, NJ. Soon after the acquisition, we began the onboarding and operationalization processes and, in October 2024, we achieved the first shipment and patient dosing from our Somerset facility. With three manufacturing suites that can meet CGMP requirements, the Somerset facility is expected to have the capacity to meet future clinical trial and commercial demands at major cancer treatment centers throughout the Northeastern U.S.

Current wording

Also in 2024, we acquired the assets and associated lease of Lantheus’ radiopharmaceutical manufacturing facility in Somerset, NJ. Soon after the acquisition, we began the onboarding and operationalization processes and, in October 2024, we achieved the first shipment and patient dosing from our Somerset facility. With three manufacturing suites that can meet CGMP requirements, the Somerset facility is expected to have the capacity to meet future clinical trial and commercial demands at major cancer treatment centers throughout the Northeastern U.S. An existing production suite in Somerset is being upgraded to support Phase 3 activities, with installation targeted for completion by mid-2026. A fourth production suite has also been installed and completed, and we expect it to be operational in 2026.

Previous wording

In October 2025, we entered into an agreement with a general contractor to begin building modifications at our facility in the Chicago, IL metropolitan area along with preparations for the eventual installation of some of the Comecer manufacturing equipment and associated clean rooms.

Current wording

In October 2025 and April 2026, we entered into agreements with a general contractor pursuant to which we expect to pay approximately $34.4 million. The first agreement is for the general contractor to make building modifications at our facility in the Chicago, IL, metropolitan area and to prepare for the installation of some of the Comecer manufacturing equipment and associated clean rooms at that site. We expect to complete construction at that site in 2026. The second agreement is for the general contractor to order long-lead time items and to prepare to make modifications to our facility in the Los Angeles, CA metropolitan area, including for the eventual installation of some of the Comecer manufacturing equipment and associated clean rooms at that site. We anticipate incurring additional spending with this general contractor, particularly in connection with the build out of our facility in the Los Angeles, CA metropolitan area.

Previous wording

On January 17, 2024, we entered into an underwriting agreement (Underwriting Agreement) with Oppenheimer & Co. Inc., as representative of the underwriters named therein (Underwriters), in connection with our underwritten public offering (Public Offering) of 13,207,521 shares (Public Shares) of our Common Stock and in lieu of Public Shares to certain investors, pre-funded warrants (Jan. 2024 Pre-funded Warrants) to purchase 3,008,694 shares of Common Stock. The price to the public for the Public Shares was $3.70 per Public Share, and the price to the public for the Jan. 2024 Pre-funded Warrants was $3.69 per Jan. 2024 Pre-funded Warrant, which represents the per share price for the Public Shares less the $0.01 per share exercise price for each such Jan. 2024 Pre-funded Warrant. Under the terms of the Underwriting Agreement, we granted the Underwriters an option, exercisable for 30 days, to purchase up to an additional 2,432,432 shares of Common Stock at the same price per share as the Public Shares, which such option was fully exercised by the Underwriters on January 18, 2024. The Public Offering closed on January 22, 2024.

Current wording

On February 2, 2026, we entered into an underwriting agreement with Piper Sandler & Co. and UBS Securities LLC, as representatives of the underwriters named therein, in connection with our previously announced underwritten offering (2026 Offering) of 39,576,088 shares (2026 Offering Shares) of our common stock, par value $0.001 per share (Common Stock), and, in lieu of 2026 Offering Shares to certain investors, pre-funded warrants (2026 Pre-funded Warrants) to purchase 6,598,046 shares of Common Stock. The price to the investors for the 2026 Offering Shares was $3.79 per 2026 Offering Share, and the price to the investors for the 2026 Pre-funded Warrants was $3.789 per 2026 Pre-funded Warrant, which represents the per share price for the 2026 Offering Shares less the $0.001 per share exercise price for each such 2026 Pre-funded Warrant. The 2026 Offering closed on February 3, 2026.

Previous wording

Our gross proceeds from the Registered Offering were approximately $80.0 million, before underwriting discounts and commissions and estimated expenses of the Offering.

Current wording

Our gross proceeds from the 2026 Offering were approximately $175.0 million, before underwriting discounts and commissions and other offering-related expenses.

Previous wording

The Jan. 2024 Pre-funded Warrants were exercisable at any time after the date of issuance. The exercise price and the number of shares of Common Stock issuable upon exercise of each Jan. 2024 Pre-funded Warrant were subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to our stockholders. The Jan. 2024 Pre-funded Warrants did not have an expiration date and were exercisable in cash or by means of a cashless exercise. A holder of Jan. 2024 Pre-funded Warrants could not exercise such Jan. 2024 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would have been more than 4.99% of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the Jan. 2024 Pre-funded Warrants. A holder of Jan. 2024 Pre-funded Warrants could increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to us. The holder of the Jan. 2024 Pre-Funded Warrants exercised all of the Jan. 2024 Pre-Funded Warrants during the fourth quarter of 2024 by means of the cashless exercise provision and within the other constraints noted above.

Current wording

The exercise price and the number of shares of Common Stock issuable upon exercise of each 2026 Pre-funded Warrant are subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to our stockholders. The 2026 Pre-funded Warrants will not expire and are exercisable in cash or by means of a cashless exercise. A holder of the 2026 Pre-funded Warrants may not exercise such 2026 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would be more than 4.99% or 9.99%, as elected by such holder, of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the 2026 Pre-funded Warrants. A holder of the 2026 Pre-funded Warrants may increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to us.

Previous wording

The Public Offering was made pursuant to our shelf registration statement on Form S-3 (File No. 333-275638), declared effective by the SEC on December 14, 2023, a base prospectus dated December 14, 2023, and the related prospectus supplement dated January 17, 2024.

Current wording

The 2026 Offering was made pursuant to our shelf registration statement on Form S-3 (File No. 333-279692), as amended, which was most recently declared effective on April 8, 2025, a related base prospectus dated April 8, 2025, and a free writing prospectus and prospectus supplement each dated February 2, 2026.

Previous wording

Research and development expenses were $20.3 million for the three months ended September 30, 2025, compared to $12.0 million for the three months ended September 30, 2024, an increase of $8.3 million. Research and development expenses were $51.3 million for the nine months ended September 30, 2025, compared to $28.8 million for the nine months ended September 30, 2024, an increase of $22.5 million. The increase in research and development expenses was primarily related to increased clinical site activities, drug program costs and delivery costs along with higher personnel costs, including share-based compensation, as we have hired employees to perform many functions previously outsourced to clinical research organizations.

Current wording

Research and development expenses were $21.4 million for the three months ended March 31, 2026, compared to $14.3 million for the three months ended March 31, 2025, an increase of $7.0 million. The increase in research and development expenses was primarily related to higher personnel costs, including share-based compensation, due to additional headcount to support our ongoing clinical trials, as well as increased spending on contract development and manufacturing organizations, clinical site activities, drug programs and delivery, pipeline studies and consulting.

Previous wording

Management believes that research and development expenses will continue to increase as we continue to invest in the development of novel radiopharmaceutical drugs and program candidates and expand our manufacturing capabilities. We are investing in equipment and modifications for the three buildings we acquired in 2024 located in the Houston, TX, Chicago, IL, and Los Angeles, CA, metropolitan areas. Upon completion, we intend to use the buildings to manufacture our program candidates. We are also working towards expanding capacity in our second manufacturing facility in Somerset, NJ, following the commencement of shipping of 212 Pb-labeled radiopharmaceuticals in the fourth quarter of 2024. We expect the capital expenditure associated with this capacity expansion to be a small portion of our total capital expenditures.

Current wording

Management believes that research and development expenses will continue to increase as we continue to invest in the development of novel radiopharmaceutical drugs and program candidates and expand our manufacturing capabilities. We are investing in equipment and modifications for the three buildings we acquired in 2024 located in the Houston, TX, Chicago, IL, and Los Angeles, CA, metropolitan areas. Upon completion, we intend to use the buildings to manufacture our program candidates.

Previous wording

Operating Activities: The increase of $66.1 million in net cash used in operating activities for the nine months ended September 30, 2025, compared to the same period in 2024 was primarily due to changes of $42.2 million in operating assets and liabilities and an increase of $26.5 million in net loss.

Current wording

Operating Activities: The increase of $9.9 million in net cash used in operating activities for the three months ended March 31, 2026, compared to the same period in 2025 was primarily due to an increase of $8.0 million in net loss and $3.1 million due to changes in operating assets and liabilities, partially offset by an increase of $1.3 million in non-cash activities.

Previous wording

Investing Activities: The increase of $93.0 million in net cash provided by investing activities for the nine months ended September 30, 2025, as compared to the same period in 2024 was primarily due to an increase of $81.5 million in maturities of short-term investments and a $32.1 million decrease in additions to property and equipment, partially offset by a $20.5 million increase in purchases of short-term investments.

Current wording

Investing Activities: The increase of $104.0 million in net cash used in investing activities for the three months ended March 31, 2026, as compared to the same period in 2025 was primarily due to an increase of $127.7 million in purchases of short-term investments and a $2.2 million increase in additions to property and equipment, partially offset by an increase of $25.9 million in maturities of short-term investments.

Previous wording

Financing Activities: Net cash provided by financing activities for the nine months ended September 30, 2025 primarily related to the proceeds received from the sale of Common Stock pursuant to the 2024 ATM Agreement (defined below). Net cash provided by financing activities of $289.0 million in the nine months ended September 30, 2024, was primarily related to various capital markets transactions and other agreements we entered into.

Current wording

Financing Activities: Net cash provided by financing activities of $164.4 million and $10.0 million for the three months ended March 31, 2026 and 2025, respectively, were primarily related to the proceeds received from the sale of Common Stock and pre-funded warrants pursuant to the 2026 Offering (defined below) and the 2024 ATM Agreement (defined below), respectively.

Previous wording

On May 24, 2024, we entered into an underwriting agreement with BofA Securities, Inc., as representative of the underwriters named therein, in connection with its previously announced underwritten offering (Registered Offering) of 5,151,588 shares (Registered Offering Shares) of our Common Stock and, in lieu of Registered Offering Shares to certain investors, pre-funded warrants (May 2024 Pre-funded Warrants) to purchase 146,425 shares of Common Stock. The price to the investors for the Registered Offering Shares was $15.10 per Registered Offering Share, and the price to the investors for the May 2024 Pre-funded Warrants was $15.09 per May 2024 Pre-funded Warrant, which represents the per share price for the Registered Offering Shares less the $0.01 per share exercise price for each such May 2024 Pre-funded Warrant. The Registered Offering closed on May 29, 2024. BofA Securities, Inc., Oppenheimer & Co. Inc. and RBC Capital Markets, LLC acted as joint book-running managers for the Registered Offering and B. Riley Securities, Inc. acted as a co-manager for the Registered Offering. JonesTrading Institutional Services LLC acted as a financial advisor for the Registered Offering.

Current wording

On February 2, 2026, we entered into an underwriting agreement with Piper Sandler & Co. and UBS Securities LLC, as representatives of the underwriters named therein, in connection with our previously announced underwritten offering (2026 Offering) of 39,576,088 shares (2026 Offering Shares) of our Common Stock, and, in lieu of 2026 Offering Shares to certain investors, pre-funded warrants (2026 Pre-funded Warrants) to purchase 6,598,046 shares of Common Stock. The price to the investors for the 2026 Offering Shares was $3.79 per 2026 Offering Share, and the price to the investors for the 2026 Pre-funded Warrants was $3.789 per 2026 Pre-funded Warrant, which represents the per share price for the 2026 Offering Shares less the $0.001 per share exercise price for each such 2026 Pre-funded Warrant. The 2026 Offering closed on February 3, 2026.

Previous wording

The gross proceeds to us from the Public Offering were approximately $69.0 million, before underwriting discounts and commissions and estimated expenses of the Public Offering.

Current wording

Our gross proceeds from the 2026 Offering were approximately $175.0 million, before underwriting discounts and commissions and other offering-related expenses.

Previous wording

The May 2024 Pre-funded Warrants became exercisable subsequent to the filing and effectiveness of an amendment to our Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware on June 14, 2024. The exercise price and the number of shares of Common Stock issuable upon exercise of each May 2024 Pre-funded Warrant were subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to our stockholders. The May 2024 Pre-funded Warrants did not have an exercise date and were exercisable in cash or by means of a cashless exercise. A holder of the May 2024 Pre-funded Warrants could not exercise such May 2024 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would have been more than 4.99% or 9.99%, as elected by such holder, of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the May 2024 Pre-funded Warrants. A holder of May 2024 Pre-funded Warrants could increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to us. The holders of the pre-funded warrants exercised all of the May 2024 Pre-funded Warrants during the second quarter of 2025 by means of the cashless exercise provision and within the other constraints noted above.

Current wording

The exercise price and the number of shares of Common Stock issuable upon exercise of each 2026 Pre-funded Warrant are subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to our stockholders. The 2026 Pre-funded Warrants will not expire and are exercisable in cash or by means of a cashless exercise. A holder of the 2026 Pre-funded Warrants may not exercise such 2026 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would be more than 4.99% or 9.99%, as elected by such holder, of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the 2026 Pre-funded Warrants. A holder of the 2026 Pre-funded Warrants may increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to us.

Previous wording

On August 13, 2024, we entered into a Controlled Equity Offering SM Sales Agreement (2024 ATM Agreement) with Cantor Fitzgerald & Co. and RBC Capital Markets, LLC (each, an ATM Agent, and together, the ATM Agents) pursuant to which we, from time to time, may offer and sell shares (2024 ATM Shares) of our common stock, par value $0.001 per share (Common Stock), through or to the ATM Agents having an aggregate sales price of up to $250.0 million.

Current wording

On August 13, 2024, we entered into a Controlled Equity Offering SM Sales Agreement (2024 ATM Agreement) with Cantor Fitzgerald & Co. and RBC Capital Markets, LLC (each, an ATM Agent, and together, the ATM Agents) pursuant to which we, from time to time, may offer and sell shares (2024 ATM Shares) of our Common Stock, through or to the ATM Agents having an aggregate sales price of up to $250.0 million.

Previous wording

We expect our expenses to increase in connection with our ongoing activities, particularly as we advance and expand preclinical activities, clinical trials and potential commercialization of our program candidates. Our costs are also expected to increase as we:

Current wording

We expect our expenses to increase in connection with our ongoing activities, particularly as we advance and expand preclinical activities, clinical trials, manufacturing activities and potential commercialization of our product candidates. Our costs are also expected to increase as we:

Previous wording

continue to initiate and progress other supporting studies required for regulatory approval of our program candidates;

Current wording

continue to initiate and progress other supporting studies required for regulatory approval of our product candidates;

Previous wording

initiate preclinical studies and clinical trials for any additional indications for our current program candidates and any future program candidates that we may pursue;

Current wording

initiate preclinical studies and clinical trials for any additional indications for our current product candidates and any future product candidates and other programs that we may pursue;