No Association Between Patient Sex and Efficacy of Immunotherapy: Study

A systematic review and meta-analysis found no significant association between patient sex and clinical benefit from immunotherapy in patients with advanced cancers.¹ An earlier study found a similar lack of association between patient sex and efficacy of chemotherapy.² The current study findings were published online January 3, 2019, in JAMA Oncology and conflict with previous evidence that suggests a difference may exist.

“It has been postulated that the advantages of immunotherapy may vary according to patient sex,” the study authors wrote, citing a meta-analysis by Conforti and colleagues that found men derived greater clinical benefit than women from immune checkpoint inhibitors.³ 

In the current study, study researchers performed a systematic review of randomized clinical trials that compared immunotherapy for advanced cancers with other systemic treatment regimens, including targeted therapies and chemotherapy. Trials that compared immunotherapy regimens or lacked overall survival (OS) data were excluded.

A total of 23 trials with 13,721 patients were included in the meta-analysis. Most of the patients were men (67.9%) and in their 70s. Most of the trials were for patients with non-small cell lung cancer (48%), melanoma (17%), clear cell renal cell carcinoma (9%), or small cell lung cancer (9%). Most of the trials evaluated a PD-L1 or PD-1 inhibitor; 26% evaluated a CTLA-4 inhibitor.

Immunotherapy conferred an OS benefit in both men (hazard ratio [HR] = 0.75; 95% confidence interval [CI], 0.69-0.81; P < .001) and women (HR = 0.77; 95% CI, 0.67-0.88; P = .002) when compared with a standard systemic treatment regimen. However, no statistically significant difference in OS benefit was seen between men and women (P = .60; I² = 38%).

“Contrary to findings of a previous analysis [by Conforti and colleagues], we found no evidence that sex should be considered when deciding whether to offer immunotherapy to patients with advanced cancers,” the study authors concluded.

References

1. Wallis CJD, Butaney M, Satkunasivam R, et al. Association of patient sex with efficacy of immune checkpoint inhibitors and overall survival in advanced cancers: A systematic review and meta-analysis [published online January 3, 2018]. JAMA Oncol. doi: 10.1001/jamaoncol.2018.5904
2. Davidson M, Wagner AD, Kouvelakis K, et al. Influence of sex on chemotherapy efficacy and toxicity in oesophagogastric (OG) cancer: a pooled analysis of four randomised trials [published online October 23, 2018]. Ann Oncol. 2018;29(suppl_8). doi: 10.1093/annonc/mdy424.032
3. Conforti F, Pala L, Bagnardi V, et al. Cancer immunotherapy efficacy and patients’ sex: A systematic review and meta-analysis. Lancet Oncol. 2018;19(6):737-746.