Tuberculosis Two studies presented at the Durban World AIDS Conference evaluated the metabolic drug interactions between anti-tuberculous agents and antiretrovirals. This is an important topic for the developing world, where the prevalence of tuberculosis is high. For the first two months, patients received only anti-TB drugs. RTV trough levels were above the IC 95 in five of the six patients assessed. No grade 3-4 liver toxicity was observed.
Hyperlipidemia is a common adverse event of protease inhibitor therapy.
Like RTV, the antifungal itraconazole is a potent inhibitor of the P450 3A4 enzyme, which plays a major role in PI clearance. Though itraconazole shares some of the pharmacological properties of RTV, it does not have anti-HIV activity. After four weeks of treatment, neither dose of itraconazole significantly altered steady-state SQV concentrations. These results contradict previous evidence that itraconazole increases SQV concentrations by five-fold. It is unclear why the investigators found no interaction.