The European Commission (EC) has approved the company’s latest product, the programmed death receptor 1 (PD-1) inhibitor nivolumab (trade name: Opdivo), for the first-line treatment of progressive unresectable malignant melanoma. As a result of favorable results from two pivotal studies, Checkmate 066 and Checkmate 037, nivolumab became the only new cancer treatment to be fast-tracked for EU approval. In the Checkmate 066 study, patients with BRAF mutation-free, untreated metastatic malignant melanoma were treated with Nivolumab or dacarbazine in first line. The results showed 1-year survival rates of 73% and 42%, respectively, with a risk ratio of 0.42 (P<0.0001)< span="">. The most common adverse reactions were fatigue (20%), pruritus (17%), and nausea (16.5%). And in the Checkmate 037 study, subjects were patients with advanced melanoma who had been previously treated with ipilimumab or who progressed on treatment with the drug. If BRAF mutation-positive patients, these patients could also have been treated with a BRAF inhibitor. An interim analysis showed that Nivolumab significantly improved objective remission rates compared to conventional chemotherapy (32% vs. 11%). Patients who were effective had longer remission periods, typically 2.6-10 months. Patient outcomes were not associated with the presence or absence of BRAF mutations or PD-1 expression status. Serious adverse reactions occurred in 41% of patients in this study, and Grade III and IV adverse reactions occurred in 42% of patients. The most common adverse reactions were abdominal pain, hyponatremia, and elevated transaminases and lipases, however, the most common adverse reaction was rash (21%). In addition, Nivolumab can cause immune-mediated pneumonia, colitis, hepatitis, and nephritis, which may cause renal dysfunction and abnormal thyroid function. In December 2014, the U.S. Food and Drug Administration (FDA) approved nivolumab for the treatment of patients with unresectable or metastatic melanoma, as well as patients with malignant melanoma whose disease has progressed after ipilimumab treatment. In March of this year, the FDA approved nivolumab for the treatment of patients with metastatic squamous non-small cell lung cancer who have progressed after platinum-based chemotherapy. However, it has not been approved for the first-line treatment of metastatic malignant melanoma.