cabotegravir + rifampin

Cabotegravir + rifampin is a combination of two **small molecule drugs** used in the context of HIV and tuberculosis (TB) co-infection. **Cabotegravir** is a long-acting integrase strand transfer inhibitor (INSTI) indicated for HIV-1 treatment and pre-exposure prophylaxis, while **rifampin** is a first-line rifamycin antibacterial used for TB. Rifampin acts as a potent inducer of metabolic enzymes, especially CYP and UGT1A1, leading to significantly reduced plasma concentrations of cabotegravir when coadministered. Studies and physiologically based pharmacokinetic (PBPK) modeling predict a 41–86% decrease in cabotegravir exposure and a pronounced reduction in effectiveness, rendering this combination generally not recommended due to risk of subtherapeutic levels and potential HIV treatment failure in TB/HIV coinfected individuals[1][3][4].