Lenacapavir and Rifabutin interaction
Lenacapavir and Rifabutin: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Rifabutin label · effective 2026-09-01
Therefore, co-administration with antiretroviral and anti-HCV drugs metabolized by CYP3A is not recommended or there may be a need to increase the dose of antiretroviral or anti-HCV drugs (see PRECAUTIONS-Drug Interactions ).
The concomitant use of protease inhibitors may require at least a 50% reduction in rifabutin dose, and depending on the protease inhibitor, an adjustment of the antiretroviral drug dose.
Co-administration with antiretroviral drugs metabolized by CYP3A, including but not limited to products containing bictegravir, elvitegravir, oral rilpivirine, or doravirine and anti-HCV drugs including but not limited to sofosbuvir (alone or in combination) may decrease plasma concentrations of those drugs, which may lead to loss of virologic response and possible…
Effect of Other Drugs on Rifabutin Pharmacokinetics Some drugs that inhibit CYP3A may significantly increase the plasma concentration of rifabutin.
Therefore, carefully monitor for rifabutin associated adverse events in those patients also receiving CYP3A inhibitors, which include fluconazole and clarithromycin.
From the Lenacapavir (Sunlenca) label · effective 2026-08-27
Concomitant administration of SUNLENCA with rifabutin or rifapentine is not recommended.
Concomitant administration of SUNLENCA with strong CYP3A inducers is contraindicated due to decreased lenacapavir plasma concentrations, which may result in the loss of therapeutic effect and development of resistance to SUNLENCA [see Drug Interactions (7.1) ] .
Concomitant administration of SUNLENCA is contraindicated with strong CYP3A inducers.
Concomitant administration of SUNLENCA with strong CYP3A inducers during SUNLENCA treatment is contraindicated [see Contraindications (4) ] .
Concomitant administration of SUNLENCA with moderate CYP3A inducers during SUNLENCA treatment is not recommended.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.