The agency is also evaluating if there's a need for further regulatory action based on reports of hematologic malignancies from clinical trials of the therapy.
The EC considered the treatment's activity in patients with advanced, PD-L1-positive esophageal and gastric cancers in the RATIONALE-305 and -306 trials.
Sarepta will pay Arrowhead Pharmaceuticals $500 million upfront, make a $325 million equity investment, plus pay $250 million over five years, and more.