Actinium Pharmaceuticals is poised for significant clinical milestones as it approaches key data readouts for its targeted radiotherapy programs. The company's lead drug candidate, Iomab-B, is currently under evaluation in the pivotal Phase III SIERRA trial for patients with relapsed or refractory acute myeloid leukemia (AML). Topline data from the fully enrolled, 150-patient study is anticipated in the fourth quarter of 2022.
Iomab-B: Targeted Conditioning for AML
Iomab-B is designed to deliver iodine-131 directly to the bone marrow, selectively targeting CD45 expressing cells. Actinium believes this targeted approach will mitigate the side effects associated with non-targeted chemotherapy and/or external beam radiation by sparing healthy tissues while effectively eliminating cancer and marrow cells. The SIERRA trial is evaluating Iomab-B as a conditioning regimen prior to hematopoietic stem cell transplantation (HSCT) in patients with active relapsed or refractory AML.
Advancing Pipeline: Iomab-ACT and Actimab-A
In addition to Iomab-B, Actinium is progressing its other investigational clinical programs. Iomab-ACT, a low-dose version of Iomab-B, is being evaluated in a Phase I/II study as a targeted conditioning agent prior to treatment with Memorial Sloan Kettering Cancer Center's (MSK) CD19-targeted CAR T-cell therapy 19-28z in patients with Diffuse large B-cell lymphoma (DLBCL) and B-cell acute lymphoblastic leukemia (B-ALL). Proof-of-concept data from the Phase I portion of this trial is expected this year. Actimab-A, an antibody radiation conjugate (ARC) targeting the CD33 receptor on blood cancer cells, is also under investigation. A Phase I trial of Actimab-A combined with CLAG-M (Cladribine, Cytarabine, G-CSF and Mitoxantrone) in patients with relapsed or refractory AML who are fit for intensive therapy has been completed, with favorable updated results reported last December. An update on the development of Actimab-A is expected this year, as well as advancement to phase II for the ongoing Phase I/II combination trial of Actimab-A and Venetoclax in patients with relapsed or refractory AML.
Financial Position
Actinium Pharmaceuticals reported a cash position of approximately $115 million as of June 30, 2022, providing financial resources to support its ongoing clinical trials and research and development activities.
