United Therapeutics licenses global rights from Arena Pharma to ralinepag for the treatment of pulmonary arterial hypertension.

Arena Pharmaceuticals, Inc. and United Therapeutics Corporation announced that the companies have entered into a global license agreement for Arena's Phase III investigational drug candidate, ralinepag, a next-generation, oral, selective and potent prostacyclin receptor agonist in development for the treatment of pulmonary arterial hypertension (PAH).

Under the terms of the agreement, Arena will grant United Therapeutics exclusive, worldwide rights to develop, manufacture and commercialize ralinepag. In return, Arena will receive up to $1.2 billion, including an upfront payment of $800 million and potential milestone payments totaling up to $400 million based on the achievement of certain regulatory events. Additionally, Arena will receive low double-digit tiered royalties on annual net sales of ralinepag.

Comment: More than 95% of United's revenue in 2017 came from products to treat PAH. The company's current array of PAH treatments include Remodulin, Tyvaso and Orenitram which accounted for roughly $1.2 billion of United's $1.7 billion revenue in 2017. The company also acquired exclusive rights in 2008 to Eli Lilly's Adcirca (tadalafil), a PDE-5 inhibitor therapy for PAH patients.