CA Inhibitor 1 Treatment Does Not Affect Estrous Cyclicity in Mice

Approximately 45% of new HIV infections worldwide occur in women and girls and adherence to pre-exposure prophylaxis (PrEP) to prevent HIV infection is limited, particularly in women. Long-acting PrEP such as lenacapavir may improve adherence. One barrier to PrEP usage in women and girls is impact on the menstrual cycle, though impacts of long-acting PrEP are unclear. To model the effect of lenacapavir administration on cyclicity, adult female C57Bl/6J mice were injected with capsid (CA) inhibitor, an analog of lenacapavir, 1 and assessed for estrous cyclicity. Injection of either CA inhibitor 1 did not impact estrous cycle. CA inhibitor 1 did not impact astrocyte immunoreactivity or chronic cellular activity in the medial preoptic area (mPOA), a major regulator of the estrous cycle. These findings warrant further investigation into the effects of lenacapavir on menstrual cycle as it may promote PrEP adherence for those concerned with PrEP impacts on menstrual cycle.