approved in Japan in July 2014 -- ahead of all the other Anti PD-1 inhibitors, worldwide. Now it is available in the US too. Off label is of course the biggest market at the moment. But the clinical studies are concluding that it works well in other cancers, beyond advanced melanoma.
So the horse race gets underway in earnest now -- it will compete head to head with Merck's Keytruda®. Per the FDA press release then, just now:
. . . .The U.S. Food and Drug Administration today granted accelerated approval to Opdivo (nivolumab), a new treatment for patients with unresectable (cannot be removed by surgery) or metastatic (advanced) melanoma who no longer respond to other drugs. . . .
Opdivo works by inhibiting the PD-1 protein on cells, which blocks the body’s immune system from attacking melanoma tumors. Opdivo is intended for patients who have been previously treated with ipilimumab and, for melanoma patients whose tumors express a gene mutation called BRAF V600, for use after treatment with ipilimumab and a BRAF inhibitor. . . .