Venetoclax is a small molecule inhibitor of BCL-2 used in the treatment of acute myelogenous leukemia (AML) and chronic lymphocytic leukemia (CLL). Recent post-marketing studies of ibrutinib, another small molecule inhibitor, suggested that these agents may predispose to opportunistic infections (OIs). We sought to systematically review the randomized controlled trial (RCT) evidence for venetoclax to assess whether it predisposes patients to infectious adverse events (IAEs) and neutropenia. We systematically reviewed RCTs comparing venetoclax therapy to active or placebo controls in patients with hematologic malignancies. Data on IAEs and neutropenia were pooled by Bayesian meta-analysis, and we computed the probability of any increased risk (P(Risk Ratio [RR]>1)) of IAEs or neutropenic complications. Results Seven RCTs were included comprising 2067 patients. In CLL (N=1032), there was a low probability of increased risk of high-grade (RR=1.11, 95%Credible Interval (95%CrI)=0.74-1.68, P(RR>1)=71.2%) and fatal IAEs (RR=1.16, 95%CrI=0.53-2.57, P(RR>1)=64.5%), nor high-grade neutropenia (RR=1.07, 95%CrI=0.64-1.74, P(RR>1)=63.4%). There was insufficient data to perform a meta-analysis of IAEs in AML; however, one trial suggested an increased risk of IAEs with venetoclax. Further, in AML (N=642), venetoclax was associated with a high probability of increased risk in high-grade neutropenia (RR=1.71, 95%CrI=0.87-3.17, P(RR>1)=94.6%) and febrile neutropenia (RR=1.49, 95%CrI=0.78-2.60, P(RR>1)=90.6%). Our results suggest that venetoclax has a low probability of increased risk of IAEs or neutropenia in CLL. By contrast, there is likely increased risk of high-grade neutropenia and febrile neutropenia in AML. Importantly, our analyses did not identify any specific IAEs that would benefit from routine antimicrobial prophylaxis or pre-emptive testing.