Study of PI3Kinase Inhibition (Copanlisib) and Anti-PD-1 Antibody Nivolumab in Relapsed/Refractory Solid Tumors With Expansions in Mismatch-repair Proficient (MSS) Colorectal Cancer

"Copanlisib will be administered as a 60 minute IV infusion (-5min/+10min) at a dose of 45 mg - 60 mg IV. Copanlisib will be administered once a week (days 1, 8, and 15 or Day 1 and Day 15 of each 28 day cycle).~Drug: 45 or 60 mg IV"

"Nivolumab 480 mg will be administered as a 30 minute IV infusion (-5min/+10min) on Day 1 of each 28 day cycle.~Drug: 480 mg IV"