FDA Drug Approvals The U.S. Food & Drug Administration (FDA) approved Incyte's immunotherapy (monoclonal antibody) drug Zynyz (retifanlimab) to treat advanced cases of Merkel Cell carcinoma (MCC), a rare skin cancer. Zynyz is administered as an intravenous infusion for 30 minutes every 4 weeks for up to 24 months. Because the drug was granted accelerated approval, it requires follow-up studies to show clinical benefit. Serious adverse reactions occurred in 22% of trial patients given retifanlimab. Immunotherapy drugs