Cellectar Biosciences has started a trial for CLR 131 in Waldenstrom’s macroglobulinemia (WM), the company announced recently.

According to a release, the trial will include 50 WM patients who will receive up to four doses of CLR 131 over two cycles. The goal is to have a response rate as defined as a partial response (a minimum of a 50% reduction in the biological marker IgM) or better in patients that receive a minimum total body dose of 60 mCI with secondary endpoints of treatment-free survival, duration of response and progression-free survival.

“CLR 131 has the potential to be an important therapeutic option for patients with Waldenstrom’s macroglobulinemia, an indication with limited treatment alternatives,” Cellectar CEO Jim Caruso said in a statement. “The 100% overall response rate achieved to date at comparable doses bodes well for CLR 131 to deliver meaningful outcomes for patients.”

The trial will be initiated at select U.S. cancer centers and will expand to U.S. and international sites in early 2021.