FDA Approves Merck’s Herceptin Biosimilar
FDA has approved Merck’s Ontruzant (trastuzumab-dttb) as a biosimilar to Genentech’s Herceptin (transtuzumab) for patients with HER2-overexpressing breast cancer. The product will be manufactured by Samsung Bioepis. The Ontruzant prescribing information says common expected side effects include headache, diarrhea, nausea, chills, fever, infection, congestive heart failure, insomnia, cough, and rash. Serious expected side effects include worsening of chemotherapy-induced neutropenia. Like Herceptin, the labeling contains a Boxed Warning for increased risks of cardiomyopathy, infusion reactions, pulmonary toxicity, and embryo-fetal toxicity.