Actinium Pharmaceuticals reports ‘positive’ Phase 3 SIERRA trial results

Actinium Pharmaceuticals announced positive SIERRA trial results in an oral presentation at the European Hematology Association 2023 Congress in Frankfurt, Germany on June 10. The abstract included data from Actinium’s SIERRA controlled phase 3 study comparing the efficacy of Iomab-B based conditioning, a first-in-class targeted radiotherapy, versus physician’s choice of conventional care in older, relapsed/refractory acute myeloid leukemia with active disease. SIERRA results demonstrate unprecedented bone marrow transplant access and outcomes with Iomab-B. BLA filing for Iomab-B expected by year end 2023 based on positive pivotal Phase 3 SIERRA results. In patients over 55 with active r/r AML, Iomab-B was able to safely deliver myeloablative doses of targeted radiation to bone marrow. Iomab-B based conditioning with bone marrow transplant resulted in rapid engraftment and high initial complete remission/complete remission with incomplete platelet recovery rates, a favorable toxicity profile and resulted in statistically significant improvement in the pre-specified primary endpoint of durable complete remission. The majority of patients who achieved dCR are long term survivors, in whom OS and EFS was significant. Iomab-B based conditioning was well-tolerated and provided access to HSCT with curative potential in a vulnerable patient population traditionally not considered eligible for HSCT.