2journals.sagepub.com/home/tai black women were under-recruited by around 35%. They also found that despite most of the global burden of HIV being in low and low-middle-income countries, most of the trials were carried out in high and high-middle-income countries. A systematicreview 5 of HIV cure research published in 2015 found that women, as well as older people and those of non-white ethnicities were profoundly under-represented.This pattern of under-recruitment is not only seen in HIV, but in many disease areas including cardiovascular disease, 7 cancer, 8 and mental health conditions. 9 Sex and gender differences 10 in the prevalence,incidence, 11 symptomatology, andprogression 12 of a range of diseases have been described, as have differences in responses to treatment. These differences in treatment responses are likely to be attributable to differences in how the body deals with a drug (pharmacokinetics) and the effect of the drug on the body (pharmacodynamics). This may affect the efficacy and tolerability of thedrug. 13 Importantly, sex 14 and gender 15 inequalities 16 in social and economic power also have a large impact on health outcomes, affecting health-seeking behaviour, access to, and utilisation of healthcare services.journals.sagepub.com/home/tai 13Visit SAGE journals online journals.sagepub.com/ home/tai