What Medicines Should Not Be Taken with Stribild?
Stribild (elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate) is a fixed dose antiretroviral treatment regimen, containing four medications in one tablet. The US Food and Drug Administration approved Stribild in August 2012 for the treatment of HIV-1 infection in adults and adolescents 12 years of age and older weighing at least 35 kilograms.
Department of Health and Human Services (DHHS) Guidelines
DHHS recommends Stribild as one of the first-line antiretroviral therapies (ART) for patients who have not received ART in the past and people who are switching to a new regimen, provided their viral load is below 50 copies/ml while on a stable regimen for at least 6 months.
This tenofovir-based medication is approved for such indications due to favorable outcomes from clinical trials. In a 144-week study, Stribild was reported to be non-inferior to Atripla and Reyataz + Truvada. In two switch studies, this regimen was found to be as potent as Protease Inhibitor (PI) + Truvada or Non-nucleoside Reverse Transcriptase Inhibitor (NNRTI) + Truvada regimens.
One of the downsides of Stribild is the addition of cobicistat—a pharmacologic enhancer that boosts the effects of HIV meds in the formulation but is associated with many drug-drug interactions. It also contains the original tenofovir prodrug that may cause kidney impairment and bone density loss. Before taking this ART regimen, talk to your doctor about all the medications you are taking, whether over the counter or prescription drugs.
Some medications that should not be taken with Stribild
Alfuzosin hydrochloride (Uroxatral) – Alfuzosin is used to treat symptoms of benign prostatic hyperplasia or enlarged prostate. Combining it with Stribild may cause harmful effects. This drug increases the amount of alfuzosin in the blood and you may experience fatigue, dizziness, or fainting due to hypotension.
Anti-seizure drugs (carbamazepine in Carbatrol, phenobarbital in Luminal, and phenytoin in Dilantin ®) – When coadministered with Stribild, these anticonvulsants may decrease the levels of elvitegravir and cobicistat, resulting to loss of antiretroviral potency. Prescribers must consider an alternative anticonvulsant.
Ergot medications (ergotamine titrate in Cafergot, dihydroergotamine mesylate in Migranal methylergonovine maleate in Ergotrate) – These ergot alkaloids are used to treat throbbing headache or migraine pains, as well as to prevent and control post-partum hemorrhage. Coadministration with these meds may cause severe drug interactions, such as elevated plasma levels of ergot alkaloids that may lead to ergot toxicity—a serious condition characterized by peripheral vasospasm and ischemia.
Midazolam – Orally administered midazolam with cobicistat-containing meds may cause increased sedation and respiratory depression. Consider parenteral administration with appropriate medical management and close monitoring.
Pimozide – Cobicistat is contraindicated with this antipsychotic drug due to possible increase concentration of pimozide in the plasma. This may result to serious heart problems such as QT prolongation and abnormal heart rhythm that can lead to sudden cardiac death (torsade de pointes).
Anti-tuberculosis drugs (rifampin, rifapentine, rifabutin) – These drugs and may decrease the plasma concentration of cobicistat. Coadministration may lead to treatment failure and drug resistance.
Protease Inhibitors (ritonavir, saquinavir, Atazanavir, darunavir) – PI drugs like ritonavir (also acts as a booster) has similar effects on CYP3A4 enzyme as cobicistat. Coadministration may cause elevated levels of these drugs in the plasma.
Salmeterol – This drug is a bronchodilator and concurrent use with cobicistat may cause increased cardiovascular problems, such as QT prolongation, sinus tachycardia, and palpitations.
Sildenafil – Sildenafil is the generic name of the erectile dysfunction (ED) drug Viagra and another drug Revatio that is used to treat pulmonary arterial hypertension. Cobicistat should not be administered with Revatio. For the ED sildenafil, maximum dose should be no more than 25mg in 48 hours.
Triazolam – This sedative drug is contraindicated with Stribild due to the risk of increased sedation and respiratory depression. Cobicistat may cause significant increase in the plasma concentration of triazolam.
St. John’s Wort – Also known as hypericum perforatum, this herbal supplement is often used to treat depression. Because St. John’s Wort induces the enzyme CYP3A4, it can lead to significant decrease in the plasma concentration of cobicistat, leading to reduced antiviral potency and development of viral resistance.
Statins (lovastatin or simvastatin) – Statins are cholesterol-lowering drugs that are substrates of CYP3A4. Coadministration can lead to increase statin plasma concentration that may cause myopathy and rhabdomyolysis syndrome.
This guide contains an incomplete list of medications that can cause severe drug-to-drug interactions with Stribild (elvitegravir, cobicistat, emtricitabine, tenofovir disoproxil fumarate). Do not discontinue your treatment regimen because of potential drug interactions without consulting your prescriber. For your safety, read the package leaflet of the drug for a complete list of adverse effects, drug interactions, and contraindications.