Gastrointestinal adverse effects of combined checkpoint inhibitors: A systematic review and meta-analysis.

Abstract

e14591 Background: Combined immune checkpoint inhibitors (ICPI) have revolutionized treatment of solid tumors. Their use can lead to treatment-related adverse events (TRAEs) resulting in hospital admissions, treatment discontinuation and increased morbidity. We aim to evaluate gastrointestinal (GI) TRAEs of different combination ICPI. Methods: A comprehensive search of multiple databases from inception to October 2021 was performed. Phase 2 and 3 trials assessing safety and efficacy of combined ICPI in solid tumors were included. Trials reporting concurrent use of chemotherapy, immunosuppressants, targeted therapy, or sequential ICPI therapy were excluded. Primary outcome was pooled luminal, hepatic and pancreatic TRAEs. A meta-analysis of proportions was done for outcomes using a random-effects model. I2 % was used to assess heterogeneity. Results: Out of 3696 citations screened, 53 trials reporting TRAEs in 6186 patients were included. Data from 41 study arms of 35 trials in nivolumab plus ipilimumab (N+I), 15 study arms of 15 trials in durvalumab plus tremelimumab (D+T), 4 study arms of 3 trials in pembrolizumab plus ipilimumab (P+I). The most common indications for combined ICPI were melanoma (26.4%) and lung cancer (24.5%). Pooled GI TRAE rates from the D+T, P+I and two different dosing combinations of N+I are shown in the table. Conclusions: Our study provides pooled data of TRAEs from different combination ICPI use in solid tumors and demonstrates high incidence of all grades and ≥ 3 GI TRAEs. Combined ICPI related TRAEs should be recognized early, as it may require treatment discontinuation. Further studies are required to assess overall impact of TRAEs on treatment course and outcomes.[Table: see text]