A Safety Study of SGN-2FF for Patients With Advanced Solid Tumors

This study is being done to find out the side effects (unwanted effects) that are caused in patients with cancers who are given SGN-2FF. This study will also attempt to find the most suitable dose in the disease or condition being studied and look at other effects of SGN2FF, including its effect on cancer.
This study has several different parts. Part A will try to find the highest safe dose. Part B will enroll more patients to be treated at the highest safe dose or a lower dose to better understand how well SGN-2FF is tolerated. Part C will try to find the highest safe dose of SGN-2FF when it is given combined with pembrolizumab. Pembrolizumab is a standard treatment for cancer. Part D will enroll more patients to be treated at the highest safe dose of SGN-2FF combined with pembrolizumab or a lower dose of SGN-2FF to better understand how well SGN-2FF is tolerated when it is given with pembrolizumab.