Actinium Pharmaceuticals, Inc.

Previous wording

Actinium Pharmaceuticals, Inc. (“Actinium”, the “Company”, or “we”) is a pioneer in the development of targeted radiotherapies intended to meaningfully improve outcomes for patients with advanced cancers including relapsed or refractory (“r/r”) disease who have failed existing therapies. We are advancing a pipeline of differentiated clinical and preclinical stage product candidates focused on validated cancer targets. Our current pipeline is focused on indications in myeloid malignancies, solid tumors and conditioning for cell and gene therapies that we believe have high unmet needs that are not addressed by currently available treatment options. Our goal is to create a specialty radiopharmaceutical company with capabilities across radioisotope production, final drug product manufacturing, preclinical research and development (“R&D”) and clinical development. We are deploying our technologies and capabilities, which we believe to be industry-leading, and intellectual property with approximately 240 issued and pending patents worldwide, to develop targeted and next-generation radiotherapies.

Current wording

Actinium Pharmaceuticals, Inc. is a pioneer in the development of targeted radiotherapies intended to meaningfully improve outcomes for patients with advanced cancers. Our goal is to create a specialty radiopharmaceutical company with capabilities across radioisotope production, final drug product manufacturing, preclinical research and development (“R&D”) and clinical development. We are deploying our technologies, capabilities and intellectual property with approximately 240 issued and pending patents worldwide, to develop next-generation radiotherapies. We are focused on developing highly differentiated and innovative first-in-class product candidates. Our current pipeline of clinical and preclinical stage targeted radiotherapy product candidates are directed against validated cancer targets for indications in hematology, solid tumors and conditioning for cell and gene therapies, which we believe have high unmet needs that are not addressed by currently available treatment options.

Previous wording

We are advancing two clinical stage product candidates that are directed against validated cancer targets. Actimab-A is our lead product candidate in development and is intended to address the significant unmet medical needs of patients with myeloid malignancies, including acute myeloid leukemia (“AML”) and myelodysplastic syndromes (“MDS”). We are also evaluating Actimab-A’s potential to synergize with PD-1 immune checkpoint inhibitors (“ICIs”) in solid tumor indications through the depletion of immune cells known as myeloid derived suppressor cells (“MDSCs”). Iomab-ACT is a next-generation targeted conditioning agent we are developing with the intent to improve patient access to, and outcomes with, cellular therapies such as CAR-T for various blood cancer indications and gene therapies for non-malignant hematologic disorders such as sickle cell disease (“SCD”). We are also developing ATNM-400, a novel preclinical, non-prostate specific-membrane antigen (“non-PSMA”) targeting, first-in-class radiotherapy utilizing the Actinium-225 (“Ac-225”) radioisotope payload intended for patients with prostate cancer directed against a novel radiotherapy target.

Current wording

We are advancing two clinical stage product candidates and one preclinical stage product candidate that are directed against validated cancer targets. Actimab-A is our most advanced clinical-stage product candidate that we are actively developing and is intended to address the significant unmet medical needs of patients with myeloid malignancies, including acute myeloid leukemia (“AML”) and myelodysplastic syndromes (“MDS”). We are also evaluating Actimab-A’s potential to synergize with PD-1 immune checkpoint inhibitors (“ICIs”) in solid tumor indications through the depletion of immune cells known as myeloid derived suppressor cells (“MDSCs”). We recently announced our ATNM-400 program, a novel preclinical, non-prostate specific-membrane antigen (“non-PSMA”) targeting, first-in-class radiotherapy utilizing the Actinium-225 (“Ac-225”) radioisotope payload intended for patients with prostate cancer directed against a novel radiotherapy target and thereby differentiated from Lu-177-PSMA-617, the active agent used in Pluvicto®, a blockbuster approved prostate cancer radiotherapy and the majority of radiotherapies in development for prostate cancer. Iomab-ACT is a next-generation targeted conditioning agent we are developing with the intent to improve patient access to, and outcomes with, cellular therapies such as CAR-T for various blood cancer indications and gene therapies for non-malignant hematologic disorders such as sickle cell disease (“SCD”).

Previous wording

Actimab-A is being developed as a targeted radiotherapeutic to leverage the Ac-225 isotope payload directed against CD33, a target expressed ubiquitously in patients with AML, MDS and other myeloid malignancies. We are attempting to leverage the mutation-agnostic ability of Ac-225 to establish Actimab-A as a backbone therapy in myeloid malignancies, which are extremely heterogenous and radiosensitive, as a single agent or in combinations with chemotherapy, targeted agents, cellular therapy and immunotherapy. Actimab-A has been studied in over 150 patients as a single agent and in combination with other modalities. This clinical experience is informing our current clinical development strategy for Actimab-A. We plan to initiate a Phase 2/3 trial with Actimab-A in combination with the chemotherapy regimen CLAG-M in patients with r/r AML based on promising results with this combination in a Phase 1b trial. In addition to our internal development efforts, we entered into a Cooperative Research and Development Agreement (“CRADA”) with the National Cancer Institute (“NCI”) in February 2023 for the development of Actimab-A for AML and other myeloid malignancies. The first Actimab-A trial initiated under the CRADA is being conducted in patients with frontline AML in combination with Venetoclax, an oral Bcl-2 inhibitor and ASTX-727, an oral hypomethylating agent (“HMA”) developed by Taiho Oncology, an Otsuka Holdings company. We anticipate that additional trials will be initiated under the NCI CRADA as multiple proposals have been submitted for review.

Current wording

Actimab-A is being developed as a targeted radiotherapeutic to leverage the Ac-225 isotope payload directed against CD33, a target expressed ubiquitously in patients with AML, MDS and other myeloid malignancies. We are attempting to leverage the mutation-agnostic ability of Ac-225 to establish Actimab-A as a backbone therapy in myeloid malignancies, which are extremely heterogenous and radiosensitive, as a single agent or in combinations with chemotherapy, targeted agents, cellular therapy and immunotherapy. Actimab-A has been studied in over 150 patients as a single agent and in combination with other modalities. This clinical experience is informing our current clinical development strategy for Actimab-A. We plan to initiate a Phase 2/3 trial with Actimab-A in combination with the chemotherapy regimen CLAG-M in patients with r/r AML based on promising results with this combination in a Phase 1b trial. In addition to our internal development efforts, we entered into a Cooperative Research and Development Agreement (“CRADA”) with the National Cancer Institute (“NCI”) in February 2023 for the development of Actimab-A for AML and other myeloid malignancies. The first Actimab-A trial initiated under the CRADA is being conducted in patients with frontline AML in combination with Venetoclax, an oral Bcl-2 inhibitor and ASTX-727, an oral hypomethylating agent (“HMA”) developed by Taiho Oncology, an Otsuka Holdings company. To date, there has been broad interest from investigators through the NCI CRADA to study Actimab-A in a variety of hematology indications that we believe may support our partnering efforts given the potential to expand the addressable market opportunity for Actimab-A.

Previous wording

ATNM-400 is our newest targeted radiotherapy program that we are advancing for prostate cancer. We believe there is a high unmet need for patients with advanced prostate cancer, particularly those who progress after receiving the targeted radiotherapy Pluvicto®. Pluvicto® (Lu-177-PSMA-617) is a prostate-specific membrane antigen (PSMA) directed targeted radiotherapy that uses the beta-particle emitting radioisotope Lutetitium-177 (“Lu-177”) that is approved for patients with metastatic prostate cancer. Pluvicto® is marketed and sold by Novartis and generated sales of $1.39 billion in 2024. ATNM-400 is differentiated from Pluvicto as it targets a different marker than PSMA that has been shown to be overexpressed in patients with prostate cancer and uses the alpha-particle emitter Ac-225, which is more potent than Lu-177 but has a shorter path length, which could result in fewer off-target effects such as xerostomia or dry mouth. Given the biology of the antigen targeted by ATNM-400 and the precise and potent cell-killing of Ac-225, we believe ATNM-400 has transformative potential to address unmet needs in prostate cancer for Pluvicto ineligible patients, after that drug has failed and even as an alternative.

Current wording

ATNM-400 is our newest targeted radiotherapy program that we are advancing for prostate cancer. We believe ATNM-400 is uniquely positioned to overcome key limitations of current standards of care in prostate cancer, including Lu-177-PSMA-617 (Pluvicto®) and the ARPI therapy enzalutamide (Xtandi®). Pluvicto® is a PSMA directed targeted radiotherapy that uses the beta-particle emitting radioisotope Lutetium-177 (“Lu-177”) that is approved for patients with metastatic prostate cancer. Pluvicto® is marketed and sold by Novartis and generated sales of approximately $1.39 billion in 2024. ATNM-400 is differentiated from Lu-177-PSMA-617 such as Pluvicto® as it targets a different marker than PSMA, which has been shown to be overexpressed in patients with prostate cancer and its expression is sustained post- Lu-177-PSMA-617 treatment. In addition, ATNM-400 uses the alpha-particle emitter Ac-225, which is more potent than Lu-177 but has a shorter path length, which could result in fewer off-target effects such as xerostomia or dry mouth as PSMA is expressed in the salivary glands. ATNM-400’s target is also implicated in resistance to androgen receptor (“AR”) inhibition. Our preclinical data has shown that ATNM-400 is effective in preclinical prostate cancer models resistant to the ARPI enzalutamide and has additive efficacy when used in combination with enzalutamide, suggesting flexibility in sequencing or combination regimens. Enzalutamide (Xtandi®) is approved for three stages of prostate cancer and is marketed and sold by Astellas and Pfizer with sales of $5.9 billion in 2024. Given the biology of the antigen targeted by ATNM-400, the precise and potent cell-killing of Ac-225 and our preclinical data to date, we believe ATNM-400 has transformative potential to address unmet needs in prostate cancer for Lu-177-PSMA-617 and enzalutamide ineligible patients, after patients become resistant to Lu-177-PSMA-617 or enzalutamide, in combination and even as an alternative treatment option.

Previous wording

In March of 2025, we initiated our Actimab-A solid tumor program that will combine Actimab-A with PD-1 checkpoint inhibitors. We initiated this program to evaluate if Actimab-A can deplete CD33 expressing MDSCs and hence improve patient outcomes in combination with PD-1 ICIs such as KEYTRUDA® and OPDIVO®. The Actimab-A solid tumor program is comprised of several controlled, head-to-head clinical trials that will evaluate the combination of Actimab-A with KEYTRUDA® versus KEYTRUDA® alone, and Actimab-A with OPDIVO® versus OPDIVO® alone. The initial tumors that are being targeted are Head and Neck Squamous Cell Carcinoma (“HNSCC”) and Non-Small Cell Lung Cancer (“NSCLC”) with a separate trial for each indication.

Current wording

We have also initiated our Actimab-A solid tumor program that will combine Actimab-A with PD-1 checkpoint inhibitors. We initiated this program to evaluate if Actimab-A can deplete CD33 expressing MDSCs and hence improve patient outcomes in combination with PD-1 ICIs such as KEYTRUDA® and OPDIVO®. The Actimab-A solid tumor program is comprised of several controlled, head-to-head clinical trials that will evaluate the combination of Actimab-A with KEYTRUDA® versus KEYTRUDA® alone, and Actimab-A with OPDIVO® versus OPDIVO® alone. The initial tumors that are being targeted are Head and Neck Squamous Cell Carcinoma (“HNSCC”) and Non-Small Cell Lung Cancer (“NSCLC”) with a separate trial for each indication.

Previous wording

Iomab-ACT is our next-generation targeted conditioning agent directed against CD45, a target expressed widely across the hematopoietic system including normal nucleated immune cells such as lymphocytes that are relevant to this program and uses the Iodine-131(“I-131") radioisotope payload. We are developing Iomab-ACT as conditioning for cell and gene therapies in both malignant and non-malignant hematologic indications. Iomab-ACT utilizes non-myeloablative doses of I-131, to not fully deplete the patient’s bone marrow and immune system with the goal of improving patient access and outcomes for potentially curative cell and gene therapies by replacing the need for the non-targeted, chemotherapy-based conditioning regimens that are currently used. Iomab-ACT is currently being studied in three clinical trials. These trials include Iomab-ACT with a commercial CAR-T therapy, Iomab-ACT prior to allogeneic BMT for patients with SCD, which could potentially inform a trial design with gene therapy for SCD, and Iomab-ACT with a novel investigational CD19 CAR-T therapy. In May 2025, we announced that the first patient was enrolled in the Iomab-ACT commercial CAR-T trial at the University of Texas Southwest Medical Center (“UTSW”).

Current wording

Iomab-ACT is our next-generation targeted conditioning agent directed against CD45, a target expressed widely across the hematopoietic system including normal nucleated immune cells such as lymphocytes that are relevant to this program and uses the Iodine-131(“I-131”) radioisotope payload. We are developing Iomab-ACT as conditioning for cell and gene therapies in both malignant and non-malignant hematologic indications. Iomab-ACT utilizes non-myeloablative doses of I-131, to not fully deplete the patient’s bone marrow and immune system with the goal of improving patient access and outcomes for potentially curative cell and gene therapies by replacing the need for the non-targeted, chemotherapy-based conditioning regimens that are currently used. Iomab-ACT is currently being studied in three clinical trials. These trials include Iomab-ACT with a commercial CAR-T therapy, Iomab-ACT prior to allogeneic bone marrow transplant for patients with SCD, which could potentially inform a trial design with gene therapy for SCD, and Iomab-ACT with a novel investigational CD19 CAR-T therapy. In May 2025, we announced that the first patient was enrolled in the Iomab-ACT commercial CAR-T trial at the University of Texas Southwest Medical Center (“UTSW”).

Previous wording

We previously advanced our targeted conditioning program Iomab-B through the Phase 3 Study of Iomab-B in Elderly Relapsed and Refractory AML (“SIERRA”) trial, a 153 patient, randomized multi-center trial conducted in the United States. and Canada. Iomab-B is comprised of the anti-CD45 monoclonal antibody apamistamab with myeloablative doses of I-131 intended to enable patient access to bone marrow transplant (“BMT”), the only potentially curative treatment option for patients with r/r AML. At this time, we are seeking a strategic partner for Iomab-B to conduct an additional clinical trial based on feedback from the U.S. Food & Drug Administration (“FDA”) and are committed to establishing the best development path forward for Iomab-B in the U.S., while keeping internal resources and strategic priorities in focus. As previously disclosed and noted above, Actinium also has a License Agreement with Immedica, granting Immedica the exclusive product rights for commercialization of Iomab-B in certain countries in the European Economic Area, Middle East and North Africa (“EUMENA”) region.

Current wording

We previously advanced our targeted conditioning program Iomab-B through the Phase 3 Study of Iomab-B in Elderly Relapsed and Refractory AML (“SIERRA”) trial, a 153 patient, randomized multi-center trial conducted in the United States and Canada. Iomab-B is comprised of the anti-CD45 monoclonal antibody apamistamab with myeloablative doses of I-131 intended to enable patient access to bone marrow transplant (“BMT”), the only potentially curative treatment option for patients with r/r AML. At this time, we are seeking a strategic partner for Iomab-B to conduct an additional clinical trial based on feedback from the FDA. We have finalized the protocol for this additional Phase 2/3 trial in agreement with the FDA and have authorization to initiate the Phase 2 portion of this trial. As previously disclosed and noted above, Actinium also has a License Agreement with Immedica, granting Immedica the exclusive product rights for commercialization of Iomab-B in certain countries in the EUMENA region.

Previous wording

Actimab-A*(Ac-225-lintuzumab satetraxetan)*is our lead radiotherapeutic product candidate in development for patients with myeloid malignancies. To our knowledge, Actimab-A is the only CD33 targeting radiotherapy in clinical development. We are focused on developing Actimab-A as both a monotherapy and in combination with other treatment regimens to leverage both the potential mechanistic synergies of radiation and its mutation agnostic cell- killing ability. In addition to our internal development efforts, we entered into a CRADA with the NCI in February 2023 for the development of Actimab-A for AML and other myeloid malignancies.

Current wording

Actimab-A*(Ac-225-lintuzumab satetraxetan)*is our most advanced radiotherapeutic product candidate in development for patients with myeloid malignancies. To our knowledge, Actimab-A is the only CD33 targeting radiotherapy in clinical development. We are focused on developing Actimab-A as both a monotherapy and in combination with other treatment regimens to leverage both the potential mechanistic synergies of radiation and its mutation agnostic cell-killing ability. In addition to our internal development efforts, we entered into a CRADA with the NCI in February 2023 for the development of Actimab-A for AML and other myeloid malignancies.

Previous wording

We have aligned with the FDA on a randomized pivotal Phase 2/3 trial to compare Actimab-A + CLAG-M to CLAG-M alone in patients with r/r AML. Based on our interactions with the FDA, this trial will first complete a Phase 2 portion where the Actimab-A dose will be optimized in combination with CLAG-M. We expect the Phase 2 portion of this trial to be initiated in the second half of 2025. Once the optimized Actimab-A dose is determined, we expect the trial will advance to the Phase 3 portion of the study, which may reduce time and resources required compared to separate Phase 2 and Phase 3 studies.

Current wording

We have aligned with the FDA on a randomized pivotal Phase 2/3 trial to compare Actimab-A + CLAG-M to CLAG-M alone in patients with r/r AML. Based on our interactions with the FDA, this trial will first complete a Phase 2 portion where the Actimab-A dose will be optimized in combination with CLAG-M. Once the optimized Actimab-A dose is determined, we expect the trial will advance to the Phase 3 portion of the study, which may reduce time and resources required compared to separate Phase 2 and Phase 3 studies.

Previous wording

In 2023, we entered into a CRADA with NCI to develop Actimab-A for the treatment of patients with AML and other hematologic malignancies. The NCI will serve as the regulatory sponsor for any clinical trials mutually approved by both parties to study Actimab-A, and the CRADA will provide support for and may accelerate the development of Actimab-A alone or in combination with chemotherapy, immunotherapy, targeted agents and other novel combinations. The CRADA studies will be overseen by the NCI in collaboration with Actinium’s clinical development team, where we have the right to review and approve all protocols and have full rights to all data. The NCI CRADA provides for us to supply Actimab-A and for NCI to cover all clinical trial execution and development expenses, which we believe will be a cost-efficient approach as opposed to a Company sponsored trial and may therefore spare our balance sheet. The NCI Cancer Therapy Evaluation Program (“CTEP”), which sponsors approximately two thirds of all combination cancer studies, will accept Letters of Intent (“LOIs”) or concepts for Phase 1, 2 or 3 studies of Actimab-A in AML and other hematological malignancies.

Current wording

In 2023, we entered into a CRADA with NCI to develop Actimab-A for the treatment of patients with AML and other hematologic malignancies. The NCI will serve as the regulatory sponsor for any clinical trials mutually approved by both parties to study Actimab-A. The CRADA will provide support for and may accelerate the development of Actimab-A alone or in combination with chemotherapy, immunotherapy, targeted agents and other novel combinations. The CRADA studies will be overseen by the NCI in collaboration with Actinium’s clinical development team, where we have the right to review and approve all protocols and have full rights to all data. The NCI CRADA provides for us to supply Actimab-A and for NCI to cover all clinical trial execution and development expenses, which we believe will be a cost-efficient approach as opposed to a Company sponsored trial and may therefore spare our balance sheet. The NCI Cancer Therapy Evaluation Program (“CTEP”), which sponsors approximately two thirds of all combination cancer studies, will accept Letters of Intent (“LOIs”) or concepts for Phase 1, 2 or 3 studies of Actimab-A in AML and other hematological malignancies.

Previous wording

In October 2024, the NCI announced that its myeloMATCH program was officially open to patient enrollment across the U.S. and Canda. MyeloMATCH is a portfolio of clinical trials to test precision medicine treatments for adults with AML or MDS being designed and led by four leading cancer research organizations including the Alliance for Clinical Trials in Oncology, Canadian Cancer Trials Group, ECOG-ACRIN Cancer Research Group, and SWOG Cancer Research Network in collaboration with the NCI National Clinical Trials Network (“NCTN”). Collectively, the myeloMATCH program expects to open trials at hundreds of cancer care sites across the U.S. and Canada with the goal of enrolling 5,000 or more patients over the next several years. Under our CRADA with the NCI, Actimab-A is part of the myeloMATCH program and may be included in future clinical trials.

Current wording

In October 2024, the NCI announced that its myeloMATCH program was officially open to patient enrollment across the U.S. and Canada. MyeloMATCH is a portfolio of clinical trials to test precision medicine treatments for adults with AML or MDS being designed and led by four leading cancer research organizations including the Alliance for Clinical Trials in Oncology, Canadian Cancer Trials Group, ECOG-ACRIN Cancer Research Group, and SWOG Cancer Research Network in collaboration with the NCI National Clinical Trials Network (“NCTN”). Collectively, the myeloMATCH program expects to open trials at hundreds of cancer care sites across the U.S. and Canada with the goal of enrolling 5,000 or more patients over the next several years. Under our CRADA with the NCI, Actimab-A is part of the myeloMATCH program and may be included in future clinical trials.

Previous wording

In March 2025, we announced the initiation of the first clinical trial to be conducted under our CRADA by NCI. The trial will evaluate the triplet combination comprised of Actimab-A, Venetoclax and ASTX-727, a novel oral HMA developed by Taiho Oncology, an Otsuka Holdings company, in frontline AML patients. Venetoclax in combination with HMAs (Ven-HMA) is approved for patients with newly diagnosed AML. We believe this trial is supported by our Actimab-A + Venetoclax combination trial that showed that combination was well-tolerated and showed supportive anti-leukemic activity. The frontline AML triplet trial is expected to enroll up to 48 patients who are newly diagnosed with AML that are age 75 and above and not eligible for intensive chemotherapy. The trial will evaluate various dose levels of Actimab-A along with dosing regimens. We expect initial clinical data to be generated from this trial in second half of 2025.

Current wording

In March 2025, we announced the initiation of the first clinical trial to be conducted under our CRADA by NCI. The trial will evaluate the triplet combination comprised of Actimab-A, Venetoclax and ASTX-727, a novel oral HMA developed by Taiho Oncology, an Otsuka Holdings company, in frontline AML patients. Venetoclax in combination with HMAs (Ven-HMA) is approved for patients with newly diagnosed AML. We believe this trial is supported by our Actimab-A + Venetoclax combination trial that showed that the combination was well-tolerated and showed supportive anti-leukemic activity. The frontline AML triplet trial is expected to enroll up to 48 patients who are newly diagnosed with AML that are age 75 and above and not eligible for intensive chemotherapy. The trial will evaluate various dose levels of Actimab-A along with dosing regimens.

Previous wording

We are progressing the further development of ATNM-400 and expect to have further updates on this program mid-2025.

Current wording

We are continuing to study and advance ATNM-400 and expect to have further updates on this program in the second half of 2025. We intend to demonstrate ATNM-400’s potential to treat prostate cancer that has become resistant to commonly used therapies such as Lu-177-PSMA-617 (the active agent in Pluvicto®) and enzalutamide to improve outcomes with mCRPC.

Previous wording

Given the significant number of patients treated with PD-1 ICIs, there is extensive data in the medical literature on outcomes in these patients. PD-1 ICIs have significantly improved patient outcomes across several solid tumor indications, however, not all patients have robust or durable responses. Multiple therapeutic modalities have been studied in combination with PD-1 ICIs in attempt to improve patient outcomes, but few combinations have produced a sufficient clinical benefit to have been approved. To our knowledge, our Actimab-A solid tumor program is the only CD33 targeted radiotherapy being evaluated in combination with PD-1 ICIs. The rationale for studying Actimab-A in combination with either KEYTRUDA®or OPDIVO®is based on the premise that depleting MDSCs with Actimab-A will improve the efficacy of these drugs.

Current wording

Given the significant number of patients treated with PD-1 ICIs, there is extensive data in the medical literature on outcomes in these patients. PD-1 ICIs have significantly improved patient outcomes across several solid tumor indications, however, not all patients have robust or durable responses. Multiple therapeutic modalities have been studied in combination with PD-1 ICIs in attempt to improve patient outcomes, but few combinations have produced a sufficient clinical benefit or have been approved. To our knowledge, our Actimab-A solid tumor program is the only CD33 targeted radiotherapy being evaluated in combination with PD-1 ICIs. The rationale for studying Actimab-A in combination with either KEYTRUDA® or OPDIVO® is based on the premise that depleting MDSCs with Actimab-A may improve the efficacy of these drugs.

Previous wording

The patient population for these trials will be adults with PD-L1 expression and locally advanced metastatic HNSCC or NSCLC randomized to either Actimab-A alone or Actimab-A with a specific checkpoint inhibitor. The objective of each trial would be to evaluate the safety and tolerability as well as following endpoints including ORR, PFS and OS. Further, the following biomarker data would be collected including the pattern of depletion of CD33+ MDSCs and T-cell activity in peripheral blood. We expect to present initial proof of concept clinical data from the first of these trials in the second half of 2025 as well as provide an update on the outlook for the rest of the trials for the Actimab-A solid tumor program.

Current wording

The patient population for these trials will be adults with PD-L1 expression and locally advanced metastatic HNSCC or NSCLC randomized to either Actimab-A alone or Actimab-A with a specific checkpoint inhibitor. The objective of each trial would be to evaluate the safety and tolerability as well as following endpoints including ORR, PFS and OS. Further, the following biomarker data would be collected including the pattern of depletion of CD33+ MDSCs and T-cell activity in peripheral blood. We are advancing these trials and expect initial proof of concept data in the first half of 2026.

Previous wording

We are studying Iomab-ACT in collaboration with Memorial Sloan Kettering Cancer Center (“MSKCC”), for conditioning prior to CAR-T therapy for patients with relapsed or refractory B-cell acute lymphoblastic leukemia (“B-ALL”) or diffuse large B-cell lymphoma (“DLBCL”). This study, funded by a NIH grant is the first study of its kind to use an ARC, with CAR-T therapy. At the 2024 Tandem Meetings | Transplantation& Cellular Therapy Meetings of ASTCT and CIBMTR, we presented results from the ongoing Phase 1 trial. No patients (0/4) developed Immune Effector Cell-Associated Neurotoxicity Syndrome (“ICANS”) of any grade, a major safety measure of the study, as ICANS is observed in 25% or more of patients with r/r B-ALL and DLBCL treated with various CAR T-cell products and negligible incidence of cytokine release syndrome (“CRS”). Additionally, Iomab-ACT demonstrated transient depletion of peripheral blood lymphocytes and monocytes. Persistence of CAR T-cells up to 8 weeks and minimal non-hematologic toxicities have been observed to date. These results prompted us to explore additional clinical trials with Iomab-ACT.

Current wording

We are studying Iomab-ACT in collaboration with Memorial Sloan Kettering Cancer Center (“MSKCC”), for conditioning prior to CAR-T therapy for patients with relapsed or refractory B-cell acute lymphoblastic leukemia (“B-ALL”) or diffuse large B-cell lymphoma (“DLBCL”). This study, funded by a NIH grant, is the first study of its kind to use CD45 targeted radiotherapy conditioning with CAR-T therapy. At the 2024 Tandem Meetings | Transplantation & Cellular Therapy Meetings of ASTCT and CIBMTR, we presented results from the ongoing Phase 1 trial. No patients (0/4) developed Immune Effector Cell-Associated Neurotoxicity Syndrome (“ICANS”) of any grade, a major safety measure of the study, as ICANS is observed in 25% or more of patients with r/r B-ALL and DLBCL treated with various CAR T-cell products and negligible incidence of cytokine release syndrome (“CRS”). Additionally, Iomab-ACT demonstrated transient depletion of peripheral blood lymphocytes and monocytes. Persistence of CAR T-cells up to 8 weeks and minimal non-hematologic toxicities have been observed to date. These results prompted us to explore additional clinical trials with Iomab-ACT.

Previous wording

We have initiated an investigator-sponsored trial studying Iomab-ACT as targeted conditioning prior to patients receiving an FDA approved commercial CAR-T therapy at UTSW. To our knowledge, this is the first trial to study a targeted radiotherapy conditioning agent with a commercial CAR-T therapy. Given the robust clinical data that exists with commercial CAR-T therapies, we believe this trial may demonstrate the potential for Iomab-ACT to improve outcomes over current chemotherapy conditioning regimens, which we are seeking to replace and provide patients better access to CAR-T. In May 2025, we announced that the first patient was enrolled in this trial, which will enroll up to 30 patients. We expect to generate initial proof-of-concept clinical data by year end 2025. The primary objectives of this study are safety, tolerability and efficacy. Secondary objectives will evaluate incidences of CRS and ICANS as well as the persistence and expansion of CAR-T cells, which has been associated with improved efficacy and patient outcomes. If successful, we believe this Phase 1b/2 trial could support a pivotal trial, which could be initiated as early as 2026.

Current wording

We have initiated an investigator-sponsored trial studying Iomab-ACT as targeted conditioning prior to patients receiving an FDA approved commercial CAR-T therapy at UTSW. To our knowledge, this is the first trial to study a targeted radiotherapy conditioning agent with a commercial CAR-T therapy. Given the robust clinical data that exists with commercial CAR-T therapies, we believe this trial may demonstrate the potential for Iomab-ACT to improve outcomes over current chemotherapy conditioning regimens, which we are seeking to replace and provide patients better access to CAR-T. In May 2025, we announced that the first patient was enrolled in this trial, which will enroll up to 30 patients. The primary objectives of this study are safety, tolerability and efficacy. Secondary objectives will evaluate incidences of CRS and ICANS as well as the persistence and expansion of CAR-T cells, which has been associated with improved efficacy and patient outcomes. If successful, we believe this Phase 1b/2 trial could support a pivotal trial, which could be initiated as early as 2026.

Previous wording

Iomab-ACT is also being studied in an investigator-led clinical trial as targeted conditioning prior to a BMT for patients with SCD in collaboration with Columbia University. Sickle cell disease is a rare, debilitating and life-threatening blood disorder with significant unmet need that affects approximately 100,000 people in the U.S. Patients with sickle cell disease have a mutation that causes red blood cells to develop a crescent or “sickle” shape, which restrict the flow in blood vessels and limit oxygen delivery to the body’s tissues, leading to severe pain and organ damage called vaso-occlusive events (“VOEs”) or vaso-occlusive crises (“VOCs”). The recurrence of these events or crises can lead to life-threatening disabilities and/or early death. A BMT is a potentially curative treatment option for patients with sickle cell disease, particularly in patients who have had complications such as strokes, acute chest crises or recurring pain crises due to their disease. We expect patient enrollment for the Phase 1 trial to commence in the first half of 2025 and enroll up to 24 patients with initial safety and efficacy results from the initial cohort of patients receiving Iomab-ACT prior to a BMT for their SCD in the second half of 2025. If safety is demonstrated, the trial is expected to inform a clinical trial to evaluate Iomab-ACT as a targeted conditioning agent prior to gene therapy for which there are two approved agents for patients with sickle cell disease, Casgevy (Vertex Pharmaceuticals, Inc.) and Lyfgenia (Bluebird Bio, Inc.).

Current wording

Iomab-ACT is also being studied in an investigator-led clinical trial as targeted conditioning prior to a BMT for patients with SCD in collaboration with Columbia University. SCD is a rare, debilitating and life-threatening blood disorder with significant unmet need that affects approximately 100,000 people in the U.S. Patients with sickle cell disease have a mutation that causes red blood cells to develop a crescent or “sickle” shape, which restrict the flow in blood vessels and limit oxygen delivery to the body’s tissues, leading to severe pain and organ damage called vaso-occlusive events (“VOEs”) or vaso-occlusive crises (“VOCs”). The recurrence of these events or crises can lead to life-threatening disabilities and/or early death. A BMT is a potentially curative treatment option for patients with sickle cell disease, particularly in patients who have had complications such as strokes, acute chest crises or recurring pain crises due to their disease. Patient recruitment for the Phase 1 trial has commenced and this trial can enroll up to 24 patients with interim data updates expected. If safety is demonstrated, the trial is expected to inform a clinical trial to evaluate Iomab-ACT as a targeted conditioning agent prior to gene therapy for which there are two approved agents for patients with sickle cell disease, Casgevy® (Vertex Pharmaceuticals, Inc.) and Lyfgenia™ (Bluebird Bio, Inc.).

Previous wording

We plan to continue to develop Iomab-ACT based on early encouraging results, ultimately with the value proposition of improving overall access and outcomes for patients who need cellular or gene therapies. We believe an opportunity exists for Iomab-ACT to potentially generate significant revenue, if it can provide one or more clinical benefits related to lower CRS, less neurotoxicity, longer duration of response or a higher overall success rate of cellular therapy due to benefits of targeted conditioning.

Current wording

We plan to continue to develop Iomab-ACT based on early encouraging results, ultimately with the value proposition of improving overall access and outcomes for patients who need cellular or gene therapies. We believe an opportunity exists for Iomab-ACT to potentially generate significant revenue, if it can provide one or more clinical benefits related to lower CRS, less ICANS (neurotoxicity), longer duration of response or a higher overall success rate of cellular therapy due to benefits of targeted conditioning.

Previous wording

Actinium continued interactions with the FDA in the third quarter of 2024 to further discuss the specifics of the additional head-to-head clinical trial required by the FDA, including the patient population, which the FDA had suggested could include all adult AML patients. In the fourth quarter of 2024, Actinium conducted a further meeting with the FDA. Based on this meeting, Actinium believes it has aligned with the FDA on the patient population for a head-to-head Phase 3 clinical trial to further evaluate allogeneic BMT using Iomab-B plus a reduced intensity conditioning regimen of Flu/TBI versus allogeneic BMT using reduced intensity conditioning comprised of cyclophosphamide plus Flu/TBI in all adult patients aged 18 and above with active AML with blasts counts greater than 5% and less than 20%. This is a broader patient population than the patients enrolled on the SIERRA trial, which only enrolled patients aged 55 and above. Further, the FDA now requires that an additional dose optimization trial demonstrating safety and efficacy be completed to calculate the dose of Iomab-B based on absorbed dose by the bone marrow, rather than the maximum tolerable dose of 24 Gy of radiation to the liver as was done in the SIERRA trial based on several interactions we had with the FDA before starting the SIERRA trial. We are actively seeking a strategic partner for Iomab-B in the U.S. to advance the head-to-head clinical trial or other clinical development activity for Iomab-B.

Current wording

Actinium continued interactions with the FDA in 2024 to further discuss the specifics of the additional head-to-head clinical trial required by the FDA, including the patient population, which the FDA had suggested could include all adult r/r AML patients. The FDA also requires that a Phase 2 dose optimization trial demonstrating safety and efficacy be completed to calculate the dose of Iomab-B based on absorbed dose by the bone marrow, rather than the maximum tolerable dose of 24 Gy of radiation to the liver as was done in the SIERRA trial based on several interactions we had with the FDA before starting the SIERRA trial. In the second quarter of 2025, Actinium conducted another meeting with the FDA. Based on this meeting, Actinium has reached agreement with the FDA on a Phase 2/3 clinical trial protocol and has been authorized by FDA to initiate the Phase 2 portion of the trial. We are actively seeking a strategic partner for Iomab-B in the U.S. to execute the Phase 2/3 clinical trial. This planned study will be conducted to establish dose optimization and evaluate allogeneic BMT using Iomab-B plus a reduced intensity conditioning regimen of Flu/TBI versus allogeneic BMT using reduced intensity conditioning comprised of cyclophosphamide plus Flu/TBI. The study population will be all adult patients aged 18 and above with active AML with blasts counts between 5 and 20 percent. This is a broader patient population than the patients enrolled on the SIERRA trial, which only enrolled patients aged 55 and above and with blast counts that exceeded 20 percent.

Previous wording

We currently believe that our targeted radiotherapies, which utilize biologic molecules, are less likely than small molecules to face pricing pressure and negotiation from the Inflation Reduction Act of 2022 (“IRA”), given that small molecules are at risk for pricing negotiations seven years after approval compared to eleven years for biologics with negotiated prices taking effect two years after selection. Further, a drug or biological product that has an orphan drug designation, which our Actimab-A and Iomab-B programs both have, for only one rare disease or condition will be excluded from the IRA’s price negotiations requirements until such time the biological products has designations for more than one rare disease or condition, or if is approved for an indication that is not within that single designated rare disease or condition, unless such additional designation or such disqualifying approvals are withdrawn by the time CMS evaluates the drug for selection for negotiation. In addition, regulatory barriers for generic large molecule biologic based targeted radiotherapies are much higher than for small molecule radioligands such as those under development or approved, namely, Pluvicto®, Lutathera®, and Xofigo®. Generic versions of certain radiopharmaceuticals utilizing peptides, which are considered small molecules, have been submitted to the FDA via the ANDA pathway. To our knowledge, only the biosimilar approach pertains to large molecule biologic-based radiotherapies filed under 351(k) BLA pathway. The regulatory pathway for a biosimilar is much more comprehensive than the pathway for generics, and it has not been proven that biosimilars are interchangeable with the innovator’s large molecule biologic targeted radiotherapy. In addition, we are not aware of any regulations that would require us to provide Actimab-A or Iomab-ACT, including their respective mAbs, lintuzumab and apamistamab, to any third party or potential competitor. Despite the above, we are aware that one or more of the policies or regulations that afford our pipeline candidates market protections may change in the future and that one or more of our product candidates may be disadvantaged by such change.

Current wording

We currently believe that our targeted radiotherapies, which utilize biologic molecules, are less likely than small molecules to face pricing pressure and negotiation from the Inflation Reduction Act of 2022 (“IRA”), given that small molecules are at risk for pricing negotiations seven years after approval compared to eleven years for biologics with negotiated prices taking effect two years after selection. Further, a drug or biological product that has an orphan drug designation, which our Actimab-A and Iomab-B programs both have, for only one rare disease or condition will be excluded from the IRA’s price negotiations requirements until such time the biological products has designations for more than one rare disease or condition, or if is approved for an indication that is not within that single designated rare disease or condition, unless such additional designation or such disqualifying approvals are withdrawn by the time CMS evaluates the drug for selection for negotiation. In addition, regulatory barriers for generic large molecule biologic based targeted radiotherapies are much higher than for small molecule radioligands such as those under development or approved, namely, Pluvicto®, Lutathera®, and Xofigo®. Generic versions of certain radiopharmaceuticals utilizing peptides, which are considered small molecules, have been submitted to the FDA via the Abbreviated New Drug Application (“ANDA”) pathway. To our knowledge, only the biosimilar approach pertains to large molecule biologic-based radiotherapies filed under 351(k) BLA pathway. The regulatory pathway for a biosimilar is much more comprehensive than the pathway for generics, and it has not been proven that biosimilars are interchangeable with the innovator’s large molecule biologic targeted radiotherapy. In addition, we are not aware of any regulations that would require us to provide Actimab-A or Iomab-ACT, including their respective mAbs, lintuzumab and apamistamab, to any third party or potential competitor. Despite the above, we are aware that one or more of the policies or regulations that afford our pipeline candidates market protections may change in the future and that one or more of our product candidates may be disadvantaged by such change.

Previous wording

Our extensive know-how related to this production technology is supported by 5 issued patents in the U.S. and 33 patents internationally and covers:

Current wording

Our extensive know-how related to this production technology is supported by 5 issued patents in the U.S. and 33 issued patents internationally and covers:

Previous wording

As of May 2025, our patent portfolio is comprised of approximately 240 issued patents and pending patent applications worldwide, which we believe constitutes a valuable business asset. Our IP includes 48 patent families, including key patents that relate primarily to our radiotherapeutic candidates. Our patent portfolio includes 20 issued patents and 51 pending patent applications in the U.S., and 170 that are issued or pending internationally. The effective lives of the issued patents in our portfolio, or patents that may issue from the pending applications in our portfolio, ranges from expirations between 2026 and 2046.

Current wording

As of August 2025, our patent portfolio is comprised of approximately 240 issued patents and pending patent applications worldwide, which we believe constitutes a valuable business asset. Our IP includes 48 patent families, including key patents that relate primarily to our radiotherapeutic candidates. Our patent portfolio includes 20 issued patents and 51 pending patent applications in the U.S., and 173 that are issued or pending internationally. The effective lives of the issued patents in our portfolio, or patents that may issue from the pending applications in our portfolio, ranges from expirations between 2026 and 2046.

Previous wording

Our patents also cover key areas of our business such as manufacturing key components of our product candidate, Actimab-A, including Ac-225 in a cyclotron. We have expertise in utilizing the alpha emitting isotope Ac-225 including clinical experience in treating approximately 150 patients with our alpha-emitter-based therapies, “gold standard” linker technology and 5 issued patents in the U.S. and 33 patents internationally related to the manufacturing of Ac-225 in a cyclotron, which we believe has the potential to produce higher quantities of Ac-225 than currently utilized methods. In addition, we also own U.S. and international patents and pending patent applications that relate to the manufacturing of Actimab-A and its use in the treatment of cancers.

Current wording

Our patents also cover key areas of our business such as manufacturing key components of our product candidate, Actimab-A, including Ac-225 in a cyclotron. We have expertise in utilizing the alpha emitting isotope Ac-225 including clinical experience in treating approximately 150 patients with our alpha-emitter-based therapies, “gold standard” linker technology and 5 issued patents in the U.S. and 33 issued patents internationally related to the manufacturing of Ac-225 in a cyclotron, which we believe has the potential to produce higher quantities of Ac-225 than currently utilized methods. In addition, we also own U.S. and international patents and pending patent applications that relate to the manufacturing of Actimab-A and its use in the treatment of cancers.

Previous wording

As of May 8, 2025, we had 31 full-time employees, 13 of whom have Ph.D. or M.D. degrees and 20 of whom are engaged in research and development and clinical development activities. In the second quarter of 2025, we conducted a work force optimization that reduced our headcount by approximately fourteen percent. As a result, we expect personnel related expenses to be reduced by approximately $1.15 million for the remainder of 2025. We do not expect this work force optimization to have a material impact on our operations or ability to execute our operating plan. We believe that we have been successful to date in attracting skilled and experienced personnel despite the competitive hiring marketing in the industry. Our employees are not covered by a collective bargaining agreement, and we believe that our relationship with our employees is excellent. We continue to engage external consultants on an as-needed basis to temporarily supplement existing staff.

Current wording

As of August 8, 2025, we had 27 full-time employees, 12 of whom have Ph.D. or M.D. degrees and 20 of whom are engaged in research and development and clinical development activities. In the second quarter of 2025, we conducted a workforce optimization aligned with our strategic pipeline prioritization that reduced our headcount by approximately fourteen percent. Also in the second quarter of 2025, Dr. Avinash Desai resigned from his position as Chief Medical Officer. There were no disagreements with the Company that contributed to Dr. Desai’s resignation. We do not expect the aforementioned workforce optimization or departures to have a material impact on our operations or ability to execute our operating plan. We believe that we have been successful to date in attracting skilled and experienced personnel despite the competitive hiring marketing in the industry. Our employees are not covered by a collective bargaining agreement, and we believe that our relationship with our employees is excellent. We continue to engage external consultants on an as-needed basis to temporarily supplement existing staff.

Previous wording

On March 31, 2025, our Board of Directors approved the cancellation of certain stock options to purchase an aggregate of 4.9 million shares of common stock held by certain current employees and directors that were initially granted under our Amended and Restated 2013 Stock Plan and 2019 Amended and Restated Stock Plan. Such cancellations were subject to the consent of the applicable holders of the stock options, which we received. Our Compensation Committee intends to conduct an analysis of our equity compensation plan and develop an equity compensation strategy that satisfies the purpose of the 2019 Plan to attract and retain the best available personnel who can make meaningful contributions towards achieving our business objectives. The cancellation of these stock options resulted in the recording of $8.7 million in non-cash stock compensation expense for the three months ended March 31, 2025. During the three months ended March 31, 2024, the Company recorded compensation expense related to stock options of $1.2 million.

Current wording

On March 31, 2025, our Board of Directors approved the cancellation of certain stock options to purchase an aggregate of 4.9 million shares of common stock held by certain current employees and directors that were initially granted under our Amended and Restated 2013 Stock Plan and 2019 Amended and Restated Stock Plan. Such cancellations were subject to the consent of the applicable holders of the stock options.

Previous wording

We recorded no commercial revenue for the three months ended March 31, 2025 and March 31, 2024.

Current wording

We recorded no commercial revenue for the three months ended June 30, 2025 and June 30, 2024, respectively.

Previous wording

Other income is comprised of net interest income in both reporting periods. The amount for the three months ended March 31, 2025 of $0.7 million decreased from $0.9 million for the three months ended March 31, 2024 primarily due to a lower average cash balance during the respective time periods.

Current wording

Other income is comprised of net interest income in both reporting periods. The amount for the three months ended June 30, 2025 of $0.6 million decreased from $1.1 million for the three months ended June 30, 2024 primarily due to a lower average cash balance during the respective time periods.

Previous wording

Net loss of $15.9 million for the three months ended March 31, 2025 increased by $7.2 million from $8.7 million for the three months ended March 31, 2024 primarily due to higher research and development expenses and higher general administrative expenses as a result of the recognition of higher non-cash stock compensation expense of $7.5 million discussed above. In the second quarter of 2025, we conducted a work force optimization that reduced our headcount by approximately fourteen percent. As a result, we expect personnel related expenses to be reduced by approximately $1.15 million for the remainder of 2025.

Current wording

Net loss of $22.8 million for the six months ended June 30, 2025 increased by $2.8 million from $20.0 million for the six months ended June 30, 2024 primarily due to higher research and development expenses and higher general administrative expenses as a result of non-cash stock-based compensation expense of $9.1 million for the six months ended June 30, 2025 compared to $2.8 million in the prior-year period due to the cancellation of stock options described above, along with lower other income.

Previous wording

Net cash used in operating activities for the three months ended March 31, 2025 was $7.6 million, an increase of $0.2 million from $7.4 million in the prior-year period. In the three months ended March 31, 2025, our net loss of $15.9 million excluding non-cash stock-based compensation expense of $8.9 million was $7.0 million. In the prior-year period, net loss of $8.7 million excluding non-cash stock-based compensation expense of $1.4 million was $7.3 million. This improvement of $0.3 million was offset by an increase in net operating assets and liabilities of $0.5 million.

Current wording

Net cash used in operating activities for the six months ended June 30, 2025 was $13.0 million, a decrease of $2.3 million from $15.3 million in the prior-year period. In the six months ended June 30, 2025, our net loss of $22.8 million excluding non-cash stock-based compensation expense of $9.1 million was $13.7 million. In the prior-year period, net loss of $20.0 million excluding non-cash stock-based compensation expense of $2.8 million was $17.2 million. This decrease in net cash used in operating activities of $3.5 million was offset by an increase in net operating assets and liabilities of $1.2 million.

Previous wording

There was no cash used in investing activities for the three months ended March 31, 2025. Cash used in investing activities was $11 thousand for the three months ended March 31, 2024 due to the purchase of equipment.

Current wording

There was no cash used in investing activities for the six months ended June 30, 2025. Cash used in investing activities was $11 thousand for the six months ended June 30, 2024 due to the purchase of equipment.

Previous wording

Cash used in financing activities for the three months ended March 31, 2025 was not material. Net cash provided by financing activities of $14.8 million for the three months ended March 31, 2024 was primarily from the sale of shares of common stock.

Current wording

Cash used in financing activities for the six months ended June 30, 2025 was not material. Net cash provided by financing activities of $24.7 million for the six months ended June 30, 2024 was primarily from the sale of shares of common stock.

Previous wording

In August 2020, we entered into the Capital on Demand™ Sales Agreement with JonesTrading Institutional Services LLC, or JonesTrading, pursuant to which we are able to sell, from time to time, through or to JonesTrading, up to an aggregate of $200 million of our common stock. On June 28, 2022, we entered into an Amendment and Restated Capital on Demand™ Sales Agreement, or the Amended Sales Agreement, with JonesTrading and B. Riley Securities, Inc. The Amended Sales Agreement modifies the original Capital on Demand™ Sales Agreement to include B. Riley as an additional sales agent thereunder. Shares of common stock are offered pursuant to a shelf registration statement on Form S-3 (File No. 333-273911), which was declared effective February 5, 2024, including a base prospectus covering the offering, issuance and sale of up to $500 million of common stock, preferred stock, warrants, units and/or subscription rights; and a sales agreement prospectus covering the offering, issuance and sale of up to a maximum aggregate offering price of $200 million of common stock that may be issued and sold under the Amended Sales Agreement. During the three months ended March 31, 2025, there were no sales of shares of common stock. For the three months ended March 31, 2024, we sold 1.8 million shares of common stock, resulting in gross proceeds of $15.0 million and net proceeds of $14.7 million. On March 31, 2025, upon filing of our Annual Report on Form 10-K for the year ended December 31, 2024, we became subject to General Instruction I.B.6 of Form S-3, pursuant to which in no event will we sell our common stock in a registered primary offering using Form S-3 with a value exceeding more than one-third of our public float in any 12 calendar month period so long as our public float remains below $75 million.

Current wording

In August 2020, we entered into the Capital on Demand™ Sales Agreement with JonesTrading Institutional Services LLC, or JonesTrading, pursuant to which we are able to sell, from time to time, through or to JonesTrading, up to an aggregate of $200 million of our common stock. On June 28, 2022, we entered into an Amendment and Restated Capital on Demand™ Sales Agreement, or the Amended Sales Agreement, with JonesTrading and B. Riley Securities, Inc. The Amended Sales Agreement modifies the original Capital on Demand™ Sales Agreement to include B. Riley as an additional sales agent thereunder. Shares of common stock are offered pursuant to a shelf registration statement on Form S-3 (File No. 333-273911), which was declared effective February 5, 2024, including a base prospectus covering the offering, issuance and sale of up to $500 million of common stock, preferred stock, warrants, units and/or subscription rights; and a sales agreement prospectus covering the offering, issuance and sale of up to a maximum aggregate offering price of $200 million of common stock that may be issued and sold under the Amended Sales Agreement. During the six months ended June 30, 2025, there were no sales of shares of common stock. For the six months ended June 30, 2024, we sold 2.9 million shares of common stock, resulting in gross proceeds of $25.2 million and net proceeds of $24.7 million.

Previous wording

** **In December 2023, FASB issued ASU 2023-09,Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to enhance the transparency and decision usefulness of income tax disclosures. The amendments in ASU 2023-09 provide improvements primarily related to the rate reconciliation and income taxes paid information included in income tax disclosures. We would be required to disclose additional information regarding reconciling items equal to or greater than five percent of the amount computed by multiplying pretax income (loss) by the applicable statutory tax rate. Similarly, we would be required to disclose income taxes paid (net of refunds received) equal to or greater than five percent of total income taxes paid (net of refunds received). The amendments in ASU 2023-09 are effective January 1, 2025. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. We are currently evaluating the impacts of ASU 2023-09 on our financial statements.

Current wording

In December 2023, the Financial Accounting Standards Board (“FASB”) issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to enhance the transparency and decision usefulness of income tax disclosures. The amendments in ASU 2023-09 provide improvements primarily related to the rate reconciliation and income taxes paid information included in income tax disclosures. We would be required to disclose additional information regarding reconciling items equal to or greater than five percent of the amount computed by multiplying pretax income (loss) by the applicable statutory tax rate. Similarly, we would be required to disclose income taxes paid (net of refunds received) equal to or greater than five percent of total income taxes paid (net of refunds received). The amendments in ASU 2023-09 are effective January 1, 2025. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. We adopted this standard effective January 1, 2025 and will report on it in our Annual Report on Form 10-K for the year ended December 31, 2025. We will update all required disclosures pursuant to ASU 2023-09 at that time.