Eleven pts were enrolled with a median age of 63 (55-78) and median PSA of 12 ng/mL (0.018–2,101). Seven pts (63%) received prior chemotherapy (docetaxel [7], cabazitaxel [3]). Pathogenic HR mutations included BRCA1 (1), BRCA2 (3), CDK12 (1), and FANCA (1).There were 2 confirmed PSA50 responses among 7 evaluable pts (28%). One pt had BRCA2 loss and 1 had PALB2 VUS (ongoing PSA response for 14 mo). Three stable disease and 1 partial response were observed among 6 pts evaluable by RECIST.The combination of rucaparib and copanlisib is well tolerated. The RP2D was rucaparib 400mg BID with copanlisib 45mg (D1, D15; 28-day cycle) with signal of efficacy.