Keytruda, a medication produced by Merck & Co., received its first authorization from the U.S. Food and Drug Administration (FDA) in 2014. This authorization was for the treatment of advanced melanoma in patients whose disease had progressed after other treatments.

The FDA approval was based on a clinical trial that demonstrated the effectiveness of Keytruda in improving survival rates for patients with advanced melanoma. The trial results showed that Keytruda significantly extended the median overall survival rate compared to the standard chemotherapy treatment [1][2].

Since its initial approval, Keytruda has received additional FDA authorizations for the treatment of various types of cancer, including non-small cell lung cancer, head and neck squamous cell carcinoma, classical Hodgkin lymphoma, urothelial carcinoma, and microsatellite instability-high (MSI-H) cancer [1][3].

In summary, Keytruda received its first FDA authorization in 2014 for the treatment of advanced melanoma, and it has since received additional authorizations for the treatment of various other types of cancer.

Sources:
[1] <https://www.drugpatentwatch.com/p/biologics/tradename/KEYTRUDA>
[2] <https://www.accessdata.fda.gov/drugsatfda_docs/label/2019/125514s040lbl.pdf>
[3] <https://www.drugs.com/history/keytruda.html>