Keytruda, a drug manufactured by Merck & Co., was approved by the U.S. Food and Drug Administration (FDA) on September 4, 2014 [1]. It was approved for the treatment of advanced melanoma, a type of skin cancer [1]. Keytruda is a type of immunotherapy, which helps the body's immune system fight cancer [1].

Keytruda was the first drug of its kind to receive FDA approval, and it has since been approved for the treatment of several other types of cancer [1]. The drug works by blocking a protein called PD-1, which allows the immune system to recognize and attack cancer cells [1].

It is important to note that while Keytruda has been approved by the FDA, it may not be covered by all insurance plans [1]. Patients should check with their insurance providers to determine coverage for this drug [1].

Sources:
[1] DrugPatentWatch.com, "Keytruda (pembrolizumab) - Patent Expiration & Drug Sales", <https://www.drugpatentwatch.com/patent/keytruda-pembrolizumab/>