A Study of MQ710 With and Without Pembrolizumab in People With Solid Tumor Cancer

This study tests a new drug called MQ710, alone or combined with pembrolizumab (an immunotherapy), injected directly into tumors in people with advanced solid cancers that have stopped responding to standard treatments. **You may be eligible if...** - You are 18 or older - You have advanced or metastatic cancer (such as skin cancers, melanoma, head and neck cancer, or other solid tumors) that has not responded to at least two prior treatments - You have at least two accessible tumors that can be directly injected - You are in generally good physical condition (able to carry out normal activity) - Your liver, kidneys, and blood counts are within acceptable ranges - You are willing to have a tumor biopsy **You may NOT be eligible if...** - You have had your spleen removed - You have an active infection requiring antibiotics - You have had a recent heart attack, stroke, or active autoimmune disease - You are pregnant or breastfeeding - You have uncontrolled brain metastases Talk to your doctor to see if this trial is right for you.