United Therapeutics has agreed to sell its Rare Pediatric Disease Priority Review Voucher (PPRV) to a subsidiary of AbbVie. United Therapeutics received the PPRV when Unituxin was approved by the FDA for the treatment of neuroblastoma, a rare pediatric disease. 

United Therapeutics will receive $350 million in cash in exchange for the PPRV. The voucher was awarded by the FDA under a provision that encourages development of new drugs and biologics for the prevention and treatment of rare pediatric diseases.

The program is intended to inspire development of new drug and biological products for prevention and treatment of certain rare pediatric diseases. A PPRV may be issued to the sponsor of a rare pediatric disease product application and would entitle the holder to Priority Review of a single New Drug Application or Biologics License Application, which reduces the target review time and could lead to an expedited approval. The sponsor receives the PPRV upon approval of the rare pediatric disease product application and it can be sold without limitation.

The transaction is subject to customary closing conditions and clearance under the Hart-Scott-Rodino Antitrust Improvements Act.