PD-1 and TIGIT co-expression identifies a circulating CD8 T cell population predictive of response to anti-PD-1 therapy in melanoma and Merkel-cell carcinoma patients
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request. ### Instruction: Identify all the mentioned drugs in the given text. Text may or may not contain drug. If they contain more than 1 drug, use ";" as delimiter and join them. ### Input: PD-1 and TIGIT co-expression identifies a circulating CD8 T cell population predictive of response to anti-PD-1 therapy in melanoma and Merkel-cell carcinoma patients ### Output: 