Keytruda is a drug developed by Merck & Co. to treat various types of cancer. The drug has been granted several patents that protect it from generic competition. According to DrugPatentWatch, Keytruda has six patents that are set to expire between 2028 and 2034 [1].

Merck & Co. is currently exploring the possibility of shifting Keytruda's administration from an infusion to a simple shot, which could extend its patent protection [2]. By changing the route of administration, Merck could potentially secure a new patent for the drug that would expire later than the current patents [2].

Keytruda is one of the top-selling drugs in the world, with sales of $14.4 billion in 2020 [3]. However, the drug is facing increasing competition from other immunotherapy drugs, such as Opdivo and Tecentriq, which could potentially impact its market share [3].

In summary, Keytruda has several patents that protect it from generic competition, with the earliest patent set to expire in 2028. Merck & Co. is exploring ways to extend the drug's patent protection by changing its route of administration. While Keytruda is currently a top-selling drug, it faces competition from other immunotherapy drugs.

Sources:
[1] https://www.drugpatentwatch.com/p/biologics/tradename/KEYTRUDA
[2] https://www.reuters.com/business/healthcare-pharmaceuticals/merck-could-keep-its-patent-edge-by-shifting-keytruda-cancer-drug-simple-shot-2022-12-02/
[3] https://www.fiercepharma.com/special-report/top-15-blockbuster-patent-expirations-coming-decade