Additional Study Information: The purpose of this study is to test the safety, tolerability, and effectiveness (how well these drugs work together) of NKTR-214 given in combination with KEYTRUDA or TECENTRIQ. We want to find out what effects, good or bad, the study drug has on the body and cancer when combined with KEYTRUDA or TECENTRIQ. The study will recruit participants at least 18 years of age with a diagnosis of: Lung Cancer (Non-Small Cell Lung Cancer (NSCLC)), Bladder Cancer (Urothelial Carcinoma), or Skin Cancer (Melanoma). NKTR-214 has not been approved to treat cancer by the U.S. FDA or any other health or regulatory authority in other countries.