Enhance disaggregation of clinical trial data3 Data collection on conditions that affect women differently or disproportionately to men must be improved. Women face a wide spectrum of health conditions that affect them differently or disproportionately to men, yet critical gaps in data collection continue to marginalize or even exclude them. A recent report found that of 52 migraine trials, 29 published data, of which only two (7%) published sex- disaggregated results, and of 320 ischaemic heart disease trials, 153 were open to both sexes and published data, of which only 26 (17%) published sex-disaggregated results despite that condition being the leading cause of death in women worldwide.43,44 Another systematic review and meta-analysis showed that only 13% of Alzheimer’s articles reported sex-stratified results.45 As a result, the physiology of women is still not well understood, and knowledge of how conditions present and respond to treatment in women is limited; hence, wrong conclusions on the safety and efficacy of drugs in women are being drawn. The first step in addressing this issue is to harmonize the terminology – especially by making a clear distinction between sex and gender – and establishing standardized data collection practices that go beyond common factors such as sex, race, ethnicity and age and include the socioeconomic status typically computed based on several factors such as income level, education and home postal code. The recently published Medical Science Sex and Gender Equity (MESSAGE) policy framework from the United Kingdom provides a strong foundation by defining sex and gender distinctions clearly.46 According to its policy framework, sex refers to biological differences between females and males, while gender is an aspect of identity that influences behaviour, self-perception and social interactions. A fundamental policy shift towards more inclusive research and data collection can help ensure that women’s health is much better understood and appropriately protected and promoted. The policies outlined in this paper aim to rectify this imbalance by focusing on inclusive data collection practices and requiring sex-specific metrics in research to ensure women’s health is no longer marginalized in the broader healthcare landscape. Bridging this data gap can pave the way for more targeted interventions, improved health outcomes and a healthcare system that better serves women. The following policy recommendations are intended to enhance disaggregation of clinical trial data, including terminology and data collection standardization (Figure 3): –Standardize terminology and data collection to improve women’s health research. Harmonizing ICH terminology – for example, sex vs. gender – and implementing consistent data collection standards, including post-marketing surveillance with sex-specific indicators, will enhance clarity and comparability in clinical research. These measures are a critical first step towards improving data disaggregation, ensuring that sex-specific differences in health outcomes are accurately captured, analysed and disseminated globally. –Require comprehensive sex-specific benefit- risk assessments to close critical gaps in clinical research. Requiring comprehensive sex-specific benefit-risk assessments, along with an intersectional analysis by race, ethnicity and age for regulatory approval, but also for journal submissions, can ensure that differences in the safety, efficacy and dosing of drugs 3.1 Policy recommendations to enhance disaggregation of clinical trial data Prescription for Change: Policy Recommendations for Women’s Health Research 16

Prescription for Change 2025