In a systematic review and meta-analysis reported in JAMA Oncology, Wallis et al found no difference in overall survival benefit in women vs men receiving immune checkpoint inhibitor treatment for advanced solid tumors. The authors noted that a prior analysis had suggested men derived a greater benefit in this setting, but methodologic issues with the prior analysis and availability of data from subsequent trials have raised doubts about the initial findings.
The study was based on 23 randomized clinical trials comparing immunotherapy with standard of care reported in advanced solid organ cancers through late 2018. All studies included overall survival as an outcome and data stratified by patient sex. Studies that compared immunotherapy regimens were not included in the analysis. Overall survival was analyzed with a test for heterogeneity between women and men to assess the null hypothesis that there was no sex-related difference in survival advantage with immunotherapy.
The 23 trials in the meta-analysis included 9,322 men (67.9%) and 4,399 women (32.1%), with most patients aged in the 70s. An overall survival benefit of immune checkpoint inhibitor treatment vs standard of care was found for both men (hazard ratio [HR] = 0.75, P < .001) and women (HR = 0.77, P = .002).
Random-effects meta-analysis of study-level differences in immunotherapy treatment effect showed no statistically significant difference between men and women (test for heterogeneity I2 = 38%, P = .60). No significant differences in outcome for men vs women were found in subgroup analyses by disease site, line of therapy, class of immunotherapy, study methodology, and proportion of women in study cohorts.
The investigators concluded, “Stratified analyses demonstrated no statistically significant association of patient sex with the efficacy of immunotherapy in the treatment of advanced cancers using overall survival as the outcome.”
Christopher J.D. Wallis, MD, PhD, of the Department of Surgery, University of Toronto, is the corresponding author for the JAMA Oncology article.
Disclosure: The study authors’ full disclosures can be found at jamanetwork.com.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.