Efavirenz and Elvitegravir, cobicistat, emtricitabine, and tenofovir interaction
Efavirenz and Elvitegravir, cobicistat, emtricitabine, and tenofovir: 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 Efavirenz label · effective 2024-03-31
Not recommended with ATRIPLA, which contains efavirenz, emtricitabine, and tenofovir disoproxil fumarate, unless needed for dose adjustment when coadministered with rifampin.
Coadministration with Related Products Coadministration of efavirenz with ATRIPLA (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg) is not recommended unless needed for dose adjustment (e.g., with rifampin), since efavirenz is one of its active ingredients.
…Efavirenz No dosage adjustment is recommended when efavirenz is given with the following: aluminum/magnesium hydroxide antacids, azithromycin, cetirizine, famotidine, fluconazole, lorazepam, nelfinavir, nucleoside reverse transcriptase inhibitors (abacavir, emtricitabine, lamivudine, stavudine, tenofovir disoproxil fumarate, zidovudine), paroxetine, and raltegravir.
From the Elvitegravir, cobicistat, emtricitabine, and tenofovir (Genvoya) label · effective 2025-02-03
Strongly induce CYP3A, which may lead to lower exposure of one or more components and loss of efficacy of GENVOYA and possible resistance.
GENVOYA should not be administered with other antiretroviral medications for treatment of HIV-1 infection.
Not Recommended with Other Antiretroviral Medications GENVOYA is a complete regimen for the treatment of HIV-1 infection; therefore, coadministration of GENVOYA with other antiretroviral medications for treatment of HIV-1 infection should be avoided.
Complete information regarding potential drug-drug interactions with other antiretroviral medications is not provided [see Contraindications (4) , Warnings and Precautions (5.2) and Clinical Pharmacology (12.3) ] .
Drugs that induce CYP3A activity are expected to increase the clearance of elvitegravir and cobicistat, resulting in decreased plasma concentration of cobicistat, elvitegravir, and TAF, which may lead to loss of therapeutic effect of GENVOYA and development of resistance (see Table 5 ).
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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.