Safety and efficacy of atezolizumab in the treatment of cancers: a systematic review and pooled-analysis

Purpose: Immune checkpoint inhibitors have developed rapidly and have demonstrated antitumor activity in various cancers. To evaluate the safety and efficacy of atezolizumab in treating cancers, we conducted this meta-analysis. Methods: Embase, PubMed, MEDLINE, the Central Register of Controlled Trials of the Cochrane Library, and the American Society of Clinical Oncology database were searched for relevant studies. The primary outcomes were any grade adverse events (AEs) and grade >= 3 AEs. The secondary outcomes were overall objective response rate, pooled 6-month progression-free survival (PFS) rate, 1-year overall survival (OS) rate, median PFS, and median OS. Results: Our meta-analysis was based on 14 clinical trials with 3,266 patients. The total risk of any grade AEs reached 69%, while grade >= 3 AEs happened in only 13% of participants. The overall atezolizumab-related death rate was 0.17%. Major common AEs involved fatigue (24.5%), decreased appetite (13.2%), nausea (12.3%), diarrhea (10.8%), pyrexia (10.7%), pruritus (9.6%), cough (9.5%), edema peripheral (8.6%), and rash (8.4%). The most common severe AEs were fatigue (2.2%), anemia (1.9%), and dyspnea (1.9%). Meanwhile, we found that 6% patients reached complete response and 16% partial response. The pooled 6-month PFS rate and 1-year OS rate were 0.36 (95% CI: 0.31-0.41) and 0.55 (95% CI: 0.49-0.61), respectively. The median PFS varied from 1.5 to 6.1 months, and the median OS ranged from 5.9 to 28.9 months. Conclusion: Atezolizumab has a considerable potential in treating cancers with an acceptable risk profile.