Strong inhibitors of CYP3A4 and P-gp together (e.g. cobicistat) do not result in a clinically meaningful increase in lenacapavir exposures. Co-administration of lenacapavir (300 mg single oral dose) and darunavir/cobicistat (800/150 mg once daily) increased lenacapavir AUC and Cmax by 94% and 130%. No dose adjustment of lenacapavir is required. If Sunlenca is discontinued, residual concentrations of lenacapavir may remain in the systemic circulation of patients for prolonged periods. These concentrations are not expected to affect the exposures of other antiretroviral agents that are initiated after discontinuation of Sunlenca.

Based on drug interaction studies conducted with lenacapavir, no clinically significant drug interactions have been observed with darunavir/cobicistat. Coadministration of lenacapavir (300 mg single oral dose) and darunavir/cobicistat (800/150 mg once daily) increased lenacapavir Cmax and AUC by 130% and 94%.