En route to BLA filing, Actinium details PhIII win for targeted radiotherapy in acute myeloid leukemia
Actinium Pharmaceuticals has spelled out the full Phase III data for its lead targeted radiotherapy — one that execs say presents a “practice expanding opportunity” in acute myeloid leukemia.
In the SIERRA trial, Actinium’s Iomab-B met the primary endpoint by helping 22% of patients achieve six-month durable complete remission following initial complete remission after a bone marrow transplant — compared to 0% of the control arm (p<0.0001).
When Actinium toplined the positive results in October, CEO Sandesh Seth told Endpoints News that the FDA chose the endpoint, not Actinium.
Looking at other metrics, the drug also doubled one-year survival, with 26.1% of the patients still alive compared to 13.1% on the control arm, excluding patients who crossed over. Median overall survival for the Iomab-B cohort was 6.4 months, compared to 3.2 months for the control arm.
The trial enrolled 153 older patients with active, relapsed or refractory acute myeloid leukemia who have already received a median of three lines of treatment, and for the control arm, physicians could choose from over 20 available meds, including chemotherapy as well as drugs targeting Bcl-2, FLT3, IDH and CD33.
“In routine clinical BMT practice, patients enrolled on SIERRA would never be considered for transplant and often have dismal outcomes,” Actinium chief medical officer Avinash Desai said in a statement.
Iomab-B is made up of the CD45-targeting antibody apamistamab conjugated to Iodine-131, a radioisotope. Actinium first licensed it from Fred Hutch researchers who had hoped to develop a replacement for standard conditioning regimen, which can be taxing but ineffective for patients.
The biotech plans to file a BLA with the FDA this year and launch an early access program.