Under-representation of women in Randomized Clinical Trials testing anticancer immunotherapy may undermine female patients care. A call to action

Disparities in utilization of novel cancer therapies in advanced stage III and IV melanoma and variance in outcomes

INTRODUCTION

Significant gains in advanced melanoma have been made through immunotherapy trials. Factors influencing equitable access and survival impact of these novel therapies are not well-defined.

METHOD

Retrospective analysis using National Cancer Database of patients with advanced stage III and IV melanoma from 2004 to 2021. Multivariable logistic regression was used to study the use of immunotherapy and Cox proportional hazard regression to evaluate overall survival (OS).

RESULTS

47,427 patients with increasing utilization of immunotherapy from 13.78% in 2004 to 65.88% by 2021. Inequitable adoption were impacted by age, sex, socioeconomic status/affordability, insurance types and residential educational/income level. Receiving immunotherapy was associated with a 44% improvement in OS (HR 0.56, 95% CI 0.54-0.57) and receiving a clinical trial-based therapy was associated with a 37% improvement (HR 0.63, 95% CI 0.53-0.75). Among patients who received immunotherapy or clinical trial-base therapy, there was 40% worse survival in non-Hispanic Black patients (HR 1.40, 95% CI 1.16-1.69) compared to non-Hispanic Whites.

CONCLUSION

There are disparities in utilization of immunotherapy that is influenced by socioeconomic status. Race and ethnicity had a significant influence in differential impact on survival outcomes of immunotherapies highlighting the importance of increasing underrepresented population participation in trials that lead to novel therapies.

Strategies for enhancing the representation of women in clinical trials: an evidence map

BACKGROUND

Equitable sex- and gender-based representation in clinical trials is an essential step to ensuring evidence-based care for women. While multi-institutional actions have led to significant improvements in the inclusion of women in trials, inequity persists in areas like sex-neutral cancers and cardiovascular disease. We sought to identify strategies described or evaluated to boost the inclusion of women in clinical trials.

METHODS

We used evidence mapping methodology to examine the breadth of relevant literature. We developed an a priori protocol and followed reporting guidance from the Preferred Reporting Items for Systematic Reviews and Meta-Analysis where applicable. We searched MEDLINE® (via PubMed) and EMBASE (via Elsevier) databases from inception through April 4, 2023, and used standardized procedures incorporating duplication and data verification. We included articles that described strategies to improve the recruitment and retention of women in clinical trials.

RESULTS

We identified 122 articles describing recruitment and retention strategies for 136 trials (377,595 women). Only one article distinguished between the sex and gender identity of participants, and none defined their use of the terms such as "women" or "female". The majority of articles (95%) described recruitment for only women, and 64% were conducted in the USA. Ninety-two articles (75%) described strategies in the context of sex-specific conditions (e.g., gynecologic diagnosis). The majority of included articles evaluated a behavioral intervention (52%), with 23% evaluating pharmacologic interventions and 4% invasive interventions. The most common trial phase for reported strategies was during outreach to potential participants (116 articles), followed by intervention delivery (76), enrollment (40), outcomes assessment (21), analysis and interpretation (3), and dissemination (4). We describe specific types of strategies within each of these phases.

CONCLUSIONS

Most of the existing literature describing strategies to improve the inclusion of women draws from trials for sex-specific conditions and is largely related to outreach to potential participants. There is little information about how and if studies have attempted to proportionally increase the inclusion of women in trials with both men and women or those focused on invasive and pharmacologic interventions. Future work in this area should focus on how to increase the participation of women in mixed-sex studies and on those areas with remaining inequities in trial participation.

Sex dimorphism and cancer immunotherapy: May pregnancy solve the puzzle?

In the immunoncology era, growing evidence has shown a clear sex dimorphism in antitumor immune response with a potential impact on outcomes upon immunecheckpoint blockade (ICI) in patients with cancer. Sex dimorphism could affect tumor microenvironment composition and systemic anticancer immunity; however, the modifications induced by sex are heterogeneous. From a clinical perspective, six metanalyses have explored the role of sex in cancer patients receiving ICI with conflicting results. Environmental and reproductive factors may further jeopardize the sex-related heterogeneity in anticancer immune response. In particular, pregnancy is characterized by orchestrated changes in the immune system, some of which could be long lasting. A persistence of memory T-cells with a potential fetal-antigen specificity has been reported both in human and mice, suggesting that a previous pregnancy may positively impact cancer development or response to ICI, in case of fetal-antigen sharing from tumor cells. On the other hand, a previous pregnancy may also be associated with a regulatory memory characterized by increased tolerance and anergy towards cancer-fetal common antigens. Finally, fetal-maternal microchimerism could represent an additional source of chronic exposure to fetal antigens and may have important immunological implications on cancer development and ICI activity. So far, the role of pregnancy dimorphism (nulliparous vs parous) in women and the impact of pregnancy-related variables remain largely underexplored in cancer patients. In this review, we summarize the evidence regarding sex and pregnancy dimorphism in the context of immune response and anticancer immunotherapy and advocate the importance of analyzing pregnancy variables on ICIs clinical trials.