After more than six years, Actinium is recording the much sought-after crackles of clinical connection in a phase 3 trial of its radiotherapy in older patients with leukemia.
The company reported that its lead asset Iomab-B succeeded at maintaining a durable complete remission six months post-bone marrow transplant compared to standard of care, passing the primary endpoint. As a result, Actinium is prepping an approval application to the FDA, with CEO Sandesh Seth pointing to the trial win as a testament to the company’s perseverance.
“Despite being perennially under-staffed and under-resourced, their passion and perseverance has yielded a clinically meaningful dividend,” Seth said in a release Monday, adding that the team will share additional data from the SIERRA trial later this year.
Iomab-B links the monoclonal antibody apamistamab with radioisotope iodine-131 to, in effect, simulate the therapeutic benefit of radiation without the toxic side effects. The main objective of the treatment is to produce a strong enough remission to allow patients to receive a bone marrow transplant, which can’t be carried out unless the cancer is sufficiently depleted. Actinium says that treatments for patients with acute myeloid leukemia (AML) often don’t lead to remission, limiting access to the procedure.
The 153-patient SIERRA trial tested Iomab-B against the conventional care of a physician’s choice, including chemotherapy and venclexta. Earlier data from the trial presented in April found that 100% of patients treated with Iomab-B were able to receive a transplant. The company noted that the trial took place at 24 leading transplant centers, which together make up more than 30% of transplants performed in the U.S. In addition to Iomab-B, Actinium is progressing Actimab-A, another AML treatment, which targets CD-33, in combination with chemotherapy or venetoclax.
Outsiders have started to take notice, with Actinium stacking up research collaborations. In January 2021, the company signed a pact with Astellas to develop targeted radiotherapies and has since added deals with AVEO Oncology and EpicentRx.
Meanwhile, Actinium is actively attempting to mitigate its understaffing issues, recently tapping two new clinical development heads. On Oct. 27, Akash Nahar, M.D., was announced as vice president of clinical development in addition to Madhuri Vusirikala, M.D., who was appointed as vice president of clinical development focused on bone marrow transplant.
News of the SIERRA trial elevated Actinium’s shares, which jumped nearly 10% after the market opened from $9.73 apiece to $10.70. As of the end of June, the company reported having roughly $116 million in cash on hand.