Forty Seven Inc. has entered an agreement with Merck KGaA to conduct a Phase 1b clinical trial combining Hu5F9-G4 with avelumab in patients with ovarian cancer.    PD-L1 and CD47 are immunosuppressant molecules overexpressed on cancer cells that send inhibitory signals to T cells and macrophages, respectively. Binding of avelumab to PD-L1 takes the brakes off T cells and, in a similar way, binding of Hu5F9-G4 to CD47 takes the brakes off macrophages.   “Ovarian cancer patie...