Merck Upends Pfizer Patent on World’s Best-Selling Vaccine

Merck Sharp & Dohme Corp. convinced an administrative patent review board a patent on Pfizer Inc.'s Prevnar 13, the world’s best-selling vaccine, is invalid.

Twenty-one of U.S. Patent No. 8,562,999‘s 22 claims are invalid as obvious, the U.S. Patent and Trademark Office’s Patent Trial and Appeal Board ruled in three related decisions. To be valid, a patent must not be obvious—the idea that an invention wouldn’t have been apparent to someone versed in the technology at the time based on existing patents on publications.

The loss is a blow to Pfizer, whose Prevnar 13 (diphtheria CRM197 protein)—which will remain on the market—earns more than any other vaccine in the world. It’s also the company’s best-selling product, bringing in $5.6 billion in 2017, according to the company’s most recent annual report, although sales have dropped 8 percent over the past two years. Immediately behind Prevnar 13 in 2017 was Lyrica (pregabalin), which generated $5.1 billion for the company. The next-best seller was Ibrance (palbociclib), at $3.1 billion.

Prevnar 13 is a pneumococcal 13-valent conjugate vaccine first approved for children from six weeks to 17 years old for immunization against diseases caused by the Streptococcus pneumoniae bacteria, including meningitis. It’s also approved for prevention of otitis media, or middle ear infection, in children from six weeks to 5 years old, as well as for those ages 50 and older to prevent pneumonia. Pneumonia is the most common disease caused by S. pneumoniae in adults.

If Pfizer appeals, the U.S. Federal Court of Appeals for the Federal Circuit would review the PTAB’s decision. Merck brought the case against Wyeth LLC, which Pfizer acquired in 2009.

Attorneys for Merck declined to comment. Attorneys for Pfizer didn’t immediately respond to Bloomberg Law’s request for comment.

The cases are Merck Sharp & Dohme Corp. v. Wyeth LLC, P.T.A.B., IPR2017-00390, 6/8/18, Merck Sharp & Dohme Corp. v. Wyeth LLC, P.T.A.B., IPR2017-00380, 6/8/18, and Merck Sharp & Dohme Corp. v. Wyeth LLC, P.T.A.B., IPR2017-00378, 6/8/18.