The impact of sex and gender on immunotherapy outcomes.

Immunotherapies are often used for the treatment, remission, and possible cure of autoimmune diseases, infectious diseases, and cancers. Empirical evidence illustrates that females and males differ in outcomes following the use of biologics for the treatment of autoimmune diseases, e.g., rheumatoid arthritis (RA), infectious diseases, e.g., influenza, and solid tumor cancers. Females tend to experience more adverse reactions than males following the use of a class of biologics referred to as immunotherapies. For immunotherapies aimed at stimulating an immune response, e.g., influenza vaccines, females develop greater responses and may experience greater efficacy than males. In contrast, for immunotherapies that repress an immune response, e.g., tumor necrosis factor (TNF) inhibitors for RA or checkpoint inhibitors for melanoma, the efficacy is reportedly greater for males than females. Despite these differences, discrepancies in reporting differences between females and males exist, with females have been historically excluded from biomedical and clinical studies. There is a critical need for research that addresses the biological (i.e., sex) as well as sociocultural (i.e., gender) causes of male-female disparities in immunotherapy responses, toxicities, and outcomes. One-size-fits-all approaches to immunotherapies will not work, and sex/gender may contribute to variable treatment success, including adherence, in clinical settings.