Actinium Pharmaceuticals Announces Publication of Results from the Phase 3 SIERRA Trial of Iomab-B in the Journal of Clinical Oncology

Core Insights - Actinium Pharmaceuticals has developed Iomab-B, the first CD45 targeted radiotherapy aimed at enabling potentially curative bone marrow transplants, representing an alternative to traditional chemotherapy approaches [1][6] - The Phase 3 SIERRA trial demonstrated significant efficacy, achieving durable Complete Remission and Event-Free Survival with high statistical significance [1][3] - Actinium plans to seek a strategic partner for further development of Iomab-B in the U.S. after completing FDA interactions for an additional clinical trial [1][6] Study Details - The SIERRA trial was a randomized, multicenter, controlled study involving 153 patients aged 55 and above with active relapsed or refractory Acute Myeloid Leukemia [2] - Patients receiving Iomab-B showed a 22% rate of durable Complete Remission compared to 0% in the control group, with a p-value of <0.0001 [3] - The trial also achieved a significant improvement in Event-Free Survival with a Hazard Ratio of 0.22 and a p-value of <0.0001 [3] Future Development - Despite positive results, the SIERRA trial did not meet the overall survival endpoint due to a high crossover rate, with nearly 60% of control patients receiving Iomab-B [3][5] - Actinium is focused on finalizing the specifics of an additional Phase 3 randomized trial to demonstrate overall survival benefits as required by the FDA for a Biologics License Application [6] - The company aims to accelerate the availability of Iomab-B for patients with high unmet needs in the context of bone marrow transplants [6][7]