How should rifabutin be dosed in children during HIV co-treatment with lopinavir/ritonavir?

In a recent publication, we address the lack of guidance on rifabutin dosing in children during  lopinavir/ritonavir (LPV/r) co-treatment. We developed a joint population pharmacokinetic model for rifabutin and its active metabolite, 25-O-desacetylrifabutin (des-rifabutin), in Nigerian children. This model further characterizes how LPV/r co-treatment affects the pharmacokinetics of rifabutin and des-rifabutin. To our knowledge, this is the first published population pharmacokinetic model of rifabutin in children. 

Our simulations show that a weight band-based dosing strategy for rifabutin can achieve consistent exposures of rifabutin and des-rifabutin comparable to those in adults, whether during treatment for TB alone or in combination with HIV treatment using LPV/r. 

The publication titled “Population pharmacokinetics of rifabutin among HIV/TB co-infected children on lopinavir/ritonavir-based antiretroviral therapy” and published in the Antimicrobial Agents and Chemotherapy journal can be found here.