Does gender impact the effectiveness of immune checkpoint inhibitors?

This study investigated whether the anti-cancer effect of immune check point inhibitors (ICIs) varied in male and females. The study found that patient gender does affect the effectiveness of ICIs.

Immune checkpoint inhibitors are drugs which treat cancer by enabling a patients immune cells to attack and kill the cancer cells. It is well established that sex difference affects immune response. However, it is not understood if sex has any effect on how well ICIs work in treating cancer.   

The study analysed data from 6,096 patients across 11 clinical trials which compared ICIs with other therapies in male and females. 2,541 had skin cancer (5 trials) and 2,192 had non-small cell lung cancer (4 trials). 821 patients had kidney cancer (1 trial) and 542 patients had cancer affecting the urinary system (1 trial). The results from 3095 male patients and 2191 female patients were analysed. The study investigated if there was a difference in overall survival (OS – length of time from date of diagnosis or start of treatment that patients are still alive) between men and women treated with ICIs. 

This study also looked at sex differences in progression free survival (PFS – length of time that a patient survives after treatment without worsening of disease) in patients treated with anti PD-1 drugs (type of ICI) compared to control groups. Control groups were treated with chemotherapy. 

The analysis found that ICI increased the overall survival significantly among the males by 38% and females by 26% in comparison with control groups.The analysis showed that OS of male patients was longer than female patients. The overall result of OS showed that males appeared to benefit more from ICI treatment than females. Among skin cancer patients, a significant difference in effectiveness was seen between females and males.

Male patients had a 43% improvement in survival and female patients had a 29% improvement in survival. Among all the comparisons between ICI immunotherapy versus chemotherapy, males had longer PFS than females. Further analysis revealed sex difference had more effect on PFS in non-small cell lung cancer patients than melanoma patients.  

The study found that males benefit more from immune checkpoint inhibitors Is for cancer treatment than females.

This study analysed data from 11 different previously done clinical trials and therefore a large amount of patient data was analysed. However, this patient data was on different types of cancer which is a limitation of the study.