The main findings from the pooled analyses were as follows: (1) the results showed that the combination of PARP and PD-L1/PD-1 inhibitors could significantly prolong PFS versus placebo; (2) in the intention-to-treat population, there was no PFS/OS difference between PARP inhibitor monotherapy and placebo; (3) the ORR was notably elevated in the combined therapy group compared with PARP inhibitor monotherapy; and (4) the most common AEs included fatigue (226, 54.5%), nausea (219, 52.8%), anemia (219, 52.8%), diarrhea (127, 30.6%), and alopecia (121, 29.2%). This evidence concerns the gene CD274 and anemia (phenotype).