PFE Pfizer Inc

By Colin Kellaher

Pfizer Inc. (PFE) on Wednesday said it agreed to buy clinical-stage biotechnology company Therachon Holding AG for up to $810 million in a deal that expands the New York drug maker's rare-disease portfolio.

Pfizer said it will pay $340 million upfront for Therachon, which has assets in development for the treatment of achondroplasia and short-bowel syndrome.

The deal also includes $470 million in milestone payments based on the development and commercialization of Therachon's A-46 for achondroplasia, a genetic condition that is the most common form of short-limbed dwarfism, Pfizer said.

There are currently no approved treatments for achondroplasia, a rare disease marked by a failure to normally convert cartilage into bone, causing patients to be short in stature.

Prior to closing, Swiss-based Therachon will spin off its development program for apraglutide, which is in phase-2 development for short-bowel syndrome, into a separate, independent company. Pfizer, which previously invested in Therachon through its venture-capital arm as part of a $60 million funding round in August, said it will hold an equity stake in the new company.

Pfizer said TA-46, which has completed phase-1 studies, has received orphan-drug designation from the U.S. Food and Drug Administration and the European Medicines Agency. The FDA's orphan-drug program gives special status to drugs and biologics for diseases and disorders that affect less than 200,000 people in the U.S. and provides for a seven-year marketing exclusivity period against competition.

"By acquiring Therachon, we hope to leverage Pfizer's leading scientific and development capabilities to more rapidly advance this potentially promising therapy for people with achondroplasia," said Mikael Dolsten, Pfizer's chief scientific officer.

Write to Colin Kellaher at colin.kellaher@wsj.com

(END) Dow Jones Newswires

May 08, 2019 08:47 ET (12:47 GMT)

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