Iomab-B Phase 3 Success: Survival Advantage in High-Risk AML Patients at EBMT Meeting

Actinium Pharmaceuticals, a company at the forefront of developing Antibody Radiation Conjugates (ARCs) and other targeted radiotherapy treatments, has announced the acceptance of their Phase 3 SIERRA trial results for an oral presentation at the European Bone Marrow Transplant Society's 50th Annual Meeting. The event will take place from April 14 to 17, 2024, in Glasgow, Scotland. The SIERRA trial focused on Iomab-B, a targeted radiotherapy conditioning agent that combines an anti-CD45 monoclonal antibody with an Iodine-131 radioisotope payload, which is designed for patients with a TP53 mutation.

The pivotal trial involved 153 patients suffering from active relapsed or refractory acute myeloid leukemia (r/r AML). The study compared the outcomes of patients who received Iomab-B and a bone marrow transplant (BMT) against those who received the physician's choice of care. Among the participants, 24% had a TP53 mutation, which is typically associated with poor prognosis. Notably, 27 of these TP53 positive patients were treated with Iomab-B. The trial demonstrated that Iomab-B significantly achieved the primary endpoint of durable Complete Remission (dCR) with a high level of statistical significance (p<0.0001), and every patient who received a therapeutic dose of Iomab-B was able to access and engage in BMT.

Dr. Hannah Choe, a medicine assistant professor at Ohio State University and an investigator in the SIERRA trial, is set to present the findings. The presentation is titled "I-131-Apamistamab-Led Allogeneic Hematopoietic Cell Transplant Demonstrates Survival Benefit and Overcomes High-Risk TP53 Mutations in Patients with R/R AML" and is scheduled for Wednesday, April 17, 2024, at 12:39 PM GMT during the session OS17-02 at the Scottish Event Campus (SEC Centre).

Actinium's Chief Medical Officer, Dr. Avinash Desai, expressed enthusiasm over the positive outcomes, particularly for patients with a TP53 mutation. He highlighted the company's focus on Europe, which accounts for 40% of global BMT transplants, and their partnership with Immedica Pharma Ab to make Iomab-B available globally.

The EBMT Annual Meeting is a significant gathering that draws over 5,500 attendees from various medical disciplines, fostering dialogue, information exchange, education, and scientific collaboration. The full program of the meeting can be accessed online.

Actinium Pharmaceuticals is dedicated to enhancing survival rates for individuals who have exhausted existing cancer treatments. Their advanced pipeline includes Iomab-B, which is in the pre-BLA & MAA (EU) stage, and Actimab-A, which is on a pivotal development path with the National Cancer Institute CRADA. Both candidates have shown the potential to extend survival for patients with r/r AML. The company also plans to expand Iomab-B's application to other blood cancers and is developing Iomab-ACT to improve outcomes in cell and gene therapy. Actinium holds an extensive patent portfolio, including patents related to the production of Ac-225 isotope in a cyclotron.