Clinical Data Early results investigating 13 patients with metastatic melanoma for efficacy and 19 patients for safety were reported. In patients naïve to anti-PD-1 treatment, objective responses were observed in four out of five (80%) patients, including one complete response (CR) and three partial responses (PR's). Four patients with progressive disease, while receiving anti-PD-1 monotherapy prior to enrollment, were observed to have stable disease (SD) while receiving KEYTRUDA and SD-101.