Rebaz M. Ali, Sami S. Omar, Shano M. Ali, Shvan H. Mohammed, Karokh K. Mohammed, Mohammed Q. Mustafa, Yousif M. Mahmood, Suhaib H. Kakamad, Hawkar A. Nasralla, Ahmed Gh. Hamasaeed, Zheer T. Hamasalih, Danar D. Mahmood, Mohammed Jalal Mohammed, Shahan Syamand Rasull, Fryad Mustafa Qadir, Berun A. Abdalla
Safety and Efficacy of Atezolizumab in Ovarian Cancer
Rebaz M. Ali, Sami S. Omar, Shano M. Ali, Shvan H. Mohammed, Karokh K. Mohammed, Mohammed Q....
Introduction
Although the efficacy of PD-L1 blockade has been evaluated in analyses that combine pharmacologically distinct antibodies, the specific efficacy and safety of atezolizumab remain unclear. This review aimed to evaluate the efficacy and safety profile of atezolizumab specifically.
Methods
PubMed/MEDLINE and CENTRAL were searched (June 2026) for phase I to III trials of atezolizumab in ovarian cancer, reported in full-text English with at least 10 evaluable patients. Randomized and single-arm designs qualified. Randomized comparisons were pooled under random-effects models with Knapp-Hartung adjustment as hazard ratios for survival and risk ratios for response and safety; single-arm rates were pooled as proportions using generalized linear mixed models. Heterogeneity was assessed with I², Cochran Q, and prediction intervals, with leave-one-out sensitivity analysis. Analyses used R 4.6.0.
Results
Twelve studies (13 reports) enrolled 3,179 patients. Atezolizumab reduced the hazard of progression (HR 0.88, 95% CI 0.83 to 0.93) and death (HR 0.86, 95% CI 0.78 to 0.96), without heterogeneity (I² = 0%), whereas objective response was unchanged (RR 0.88, 95% CI 0.52 to 1.49). Excess toxicity was immune-mediated, raising serious adverse events (RR 1.32, 95% CI 1.05 to 1.67), any-grade immune-related events (RR 1.57, 95% CI 1.12 to 2.20), and grade ≥3 immune-related events (RR 2.23, 95% CI 1.05 to 4.74).
Conclusion
Atezolizumab adds a small survival benefit to a chemotherapy or bevacizumab backbone, driven by delayed progression rather than tumor regression. Offset by doubled immune toxicity and inseparable from its backbone, the effect may not justify routine use.
