Phase II Fail Prompts Acceleron to Discontinue Development of Renal Cell Carcinoma Drug

Biopharmaceutical company Acceleron has announced their renal cell carcinoma (RCC) drug combo failed to meet its primary endpoint in a Phase II clinical trial, prompting the company to discontinue development of the candidate. The combination of the experimental drug dalantercept and approved cancer drug axitinib did not demonstrate a statistically significant increase in progression-free survival compared to a placebo in the DART clinical trial.

In all, 131 patients with an advanced form of RCC were enrolled in the Phase II clinical trial. Patients were randomly assigned to received dalantercept plus axitinib or placebo plus axitinib.

Median progression-free survival for patients in the treatment group was 6.8 months which was not statistically significant compared to the 5.6 months for patients given the placebo. What’s more, the treatment failed to decrease the rate of disease progression and death.

Dalantercept is a protein that binds to the activin receptor-like kinase 1 (ALK1) on proliferating vascular endothelial cells and prevents binding of the BMP9 protein. In this way, the biologic drug inhibits angiogenesis and prevents cancerous tumors from receiving the oxygen and nutrients required for them to proliferate.

Axitinib was originally developed by Pfizer as a tyrosine kinase inhibitor that targets the vascular endothelial growth factor receptor (VEGF). In 2012, the drug was approved by the FDA to treat patients with RCC.

“We designed a robust Phase II study to evaluate the efficacy of dalantercept in combination with anti-VEGF therapy in advanced renal cell carcinoma patients whose disease has progressed on prior anti-VEGF therapy,” said Habib Dable, President and Chief Executive Officer of Acceleron. “We are disappointed by the results given the need for new agents that improve outcomes for patients with advanced RCC. Based on the lack of efficacy, we are discontinuing the development of dalantercept.”

Dalantercept was the only drug candidate in Acceleron’s oncology pipeline, however the company has other compounds in various stages of development in the hematology and neuromuscular space.