Coherus Biosciences is seeking to invalidate Amgen Inc.'s patent regarding etanercept, the main component of rheumatoid arthritis drug Enbrel.
The patent does not expire until 2029.
Coherus seeks to invalidate Amgen's etanercept patent in the interest of its biosimilar, CHS-0214, which recently yielded phase 3 results. Recently, Daiichi Sankyo Co. Ltd. decided to discontinue development of CHS-0214 in Japan.
The company filed a petition for inter partes review at the U.S. Patent and Trademark Office. The inter partes review looks at the invalidity of patents in terms of novelty and obviousness in light of prior art.
Coherus said it is also looking at filing a petition to invalidate another Amgen-held patent that does not expire until 2028 and is generally directed toward etanercept protein.
The U.S. Food and Drug Administration recently rejected another Coherus biosimilar application for Amgen's chemotherapy drug, Neulasta.