Arqule Inc. CEO Paolo Pucci said the firm was “limited in what we can comment [on] for the time being” in connection with Merck & Co. Inc.’s deal to pay about $2.7 billion in cash for the company. “There is no better model for bringing a drug faster into the hands of patients and caregivers than the example of Keytruda. I will leave it at that.” Merck’s Keytruda (pembrolizumab), a human PD-1-blocking antibody was first approved in September 2014 for advanced melanoma. The label has been widely expanded since.