FDA Orphan Status for Five Prime Tumor Therapy

FDA has granted Five Prime Therapeutics an orphan drug designation for FPA008 for treating pigmented villonodular synovitis (PVNS), a locally aggressive tumor of the synovium. The investigational antibody works by blocking the activation and survival of the macrophages that make up the bulk of the PVNS tumor. The rare tumor is characterized by local over-expression of CSF-1, which recruits macrophages into the joints, forming the non-malignant tumor mass, according to the company.

Five Prime is currently conducting a Phase 1 clinical trial involving the therapy. “Inhibition of CSF1R in preclinical models of several cancers reduces the number of immunosuppressive tumor-associated macrophages in the tumor microenvironment, thereby facilitating an immune response against tumors,” the company says. FPA008 is being developed under an exclusive worldwide license and collaboration agreement with Bristol-Myers Squibb.