The FDA has granted CTI BioPharma’s Vonjo (pacritinib) accelerated approval for treating adults with intermediate- or high-risk myelofibrosis, rare forms of bone marrow disorders.

The approval was supported by a 63-person phase 3 trial in which nine patients given Vonjo showed a 35 percent or greater spleen volume reduction compared with just one patient in the standard treatment group.

Under the terms of the accelerated approval, the FDA said CTI BioPharma must conduct a follow-up confirmatory trial to prove that spleen volume reduction actually causes a clinical benefit.