Keytruda, a medication produced by Merck & Co. for the treatment of various forms of cancer, initially received approval from the U.S. Food and Drug Administration (FDA) on September 4, 2014 [1]. This approval was granted for the treatment of advanced melanoma, a type of skin cancer [1]. Since its initial approval, Keytruda has received additional approvals from the FDA for the treatment of other types of cancer, including lung, head and neck, classical Hodgkin lymphoma, urothelial carcinoma, and microsatellite instability-high (MSI-H) cancer [1].

According to DrugPatentWatch.com, Keytruda's active ingredient, pembrolizumab, was first patented in 2006 [2]. The patents for pembrolizumab are set to expire in 2028 [2]. However, it is important to note that these patents may be subject to challenges and extensions, which could potentially impact the availability of generic versions of Keytruda [2].

In summary, the FDA initially approved Keytruda for the treatment of advanced melanoma on September 4, 2014 [1]. The active ingredient in Keytruda, pembrolizumab, was first patented in 2006 and is set to expire in 2028 [2].

Sources:
[1] FDA. (2022). Highlights of Prescribing Information: Keytruda (pembrolizumab) Injection, for intravenous use [PDF]. U.S. Food and Drug Administration. <https://www.fda.gov/media/84575/download>
[2] DrugPatentWatch.com. (2022). Keytruda (pembrolizumab) Patents. <https://www.drugpatentwatch.com/Drug/Keytruda.html>