Distinguishing between contract law and patent law, the U.S. Court of Appeals for the Third Circuit ruled against a Merck KGaA subsidiary, saying Ares Trading SA is still on the hook for paying royalties to a research partner through 2027 on sales of its cancer drug Bavencio (avelumab), a PD-L1 inhibitor granted accelerated approval in 2017 as a treatment for metastatic Merkel cell carcinoma.