Can you tell me when keytruda was first approved by the fda generally?

Keytruda (pembrolizumab) was first approved by the U.S. Food and Drug Administration (FDA) on September 4, 2014 for the treatment of unresectable or metastatic melanoma that had progressed after earlier therapy, and for patients with BRAF V600 wild-type disease or those who had progressed after BRAF-targeted therapy and immunotherapy when appropriate. [1]

Sources:
[1] https://www.drugs.com/history/pembrolizumab.html