Actinium to present four presentations at ASH on lomab-B, Actimab-A

Actinium Pharmaceuticals highlighted four presentations at the 65th Annual American Society of Hematology Annual Meeting & Exposition, ASH, detailing results from the Phase 3 SIERRA trial of Iomab-B and Phase 1 trial of Actimab-A in combination with Venetoclax in patients with relapsed or refractory acute myeloid leukemia, r/r AML. ASH Presentations and Highlights: 131I-Apamistamab-Led Allogeneic Hematopoietic Cell Transplant Significantly Improves Overall Survival in Patients with TP53 Mutated R/R AML : Patients receiving Iomab-B had significantly greater median overall survival of 5.49 months compared to 1.66 months in patients on the control arm that received conventional care; Iomab-B produced response rates and overall survival in these very high-risk patients similar to those observed in patients without a TP53 mutation. 131I-Apamistamab Effectively Achieved Durable Responses in Patients with R/R AML Irrespective of the Presence of Multiple High-Risk Factors: Patients receiving Iomab-B were able to receive a BMT and achieve durable Complete Remission, the primary endpoint in the SIERRA trial, irrespective of having multiple high-risk factors; Iomab-B met the dCR rate primary endpoint with high statistical significance with 22% dCR rate in the Iomab-B arm vs. 0% dCR rate in the control arm; There was no statistical difference in the rate of dCR in patients receiving Iomab-B across the high risk-factor categories. High-Dose Targeted Radiation with 131I-Apamistamab Prior to HCT Demonstrated a Dose-Response for Durable Complete Remission in Patients with R/R AML; Patients with higher bone marrow/liver absorbed dose ratios experienced considerably higher rates of dCR demonstrating a dose dependent response; 27% of patients achieving dCR when receiving greater than 22 Gy to the liver vs 13.5% dCR rate in patients receiving less than 22 Gy to the liver; maximum tolerable dose in SIERRA was 24 Gy administered to the liver; Rates of Grade 3 greater than treatment emergent events were similar between patients receiving less than 22 Gy to the liver and those receiving greater than 22 Gy to the liver; Iomab-B led BMT produced to significantly higher rates of dCR with patients achieving dCR having a 92% 1-year overall survival and 60% 2-year overall survival. Updated Results from Phase 1 Study of Targeted Radiotherapy with Lintuzumab-Ac225 in Combination with Venetoclax in Relapsed/Refractory AML: Actimab-A dosed up to 2.0 muCi/kg with Venetoclax in patients with relapsed/refractory AML was well-tolerated, with a manageable adverse event profile; Maximum tolerated dose was not reached with no dose-limiting toxicities observed at the 3 highest dose levels; Complete responses were achieved including a complete response in a patients with prior Venetoclax treatment and a TP53 mutation.