Efavirenz in an Obese HIV-Infected Patient – a Report and An In Vitro–In Vivo Extrapolation Model Indicate Risk of Underdosing

Here, we report suboptimal efavirenz exposure in an obese patient treated with the standard 600 mg dose. Tripling the dose allowed attainment of therapeutic efavirenz concentrations. We developed an in vitro–in vivo extrapolation model to quantify dose requirements in obese individuals. Obesity represents a risk factor for antiretroviral therapy underdosing.

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