Arena’s run of positive news continues, with a massive $800 million upfront licensing deal with United Therapeutics for its pulmonary arterial hypertension drug ralinepag. The global deal, which also includes $400 million in milestones and double-digit royalties, comes on the heels of well-regarded phase 2 data with the oral prostacyclin receptor agonist in PAH that caused Arena’s shares to soar when it was released last year.