Last Updated June 10, 2016
Reyataz, Aspen Atazanavir
HIV protease inhibitor antiretroviral
150 mg, 200 mg capsules
Indication: treatment of HIV infection in combination with other antiretrovirals; postexposure prophylaxis when lopinavir/ritonavir or efavirenz are not well tolerated (also in combination with other antiretrovirals).
Mechanism of action*: inhibits cleavage of viral gag-pol polyproteins precursors into functional proteins by binding to the HIV protease enzyme.
Pharmacokinetics*: metabolized in the liver CYP 450 3A4. Half-life: 7 hours (without ritonavir), 9-18 hours (with ritonavir). Food enhances bioavailability and reduces pharmacokinetic variability.
Take with food.*
See below for caution with stomach acid–suppressing medications.*
Use in Renal or Hepatic Insufficiency:
Use in Pregnancy and Breastfeeding: No recommendation.
Use in Children: Optimal dose not established.
See Drug–Drug Interactions.
A mild or moderate maculopapular rash can develop in the first 3 weeks of therapy; if severe rash occurs, discontinue therapy.
Contraindicated*: lovastatin, simvastatin, rifampicin, cisapride, pimozide, midazolam, triazolam, dihydroergotamine, ergonovine, ergotamine, methylergonovine, St John’s wort, nevirapine, alfuzosin, irinotecan, sildenafil for pulmonary arterial hypertension, indinavir.
Atazanavir with stomach acid–suppressing agents*:
Increased concentrations of concomitant medication*: antiarrhythmics, buprenorphine, warfarin, carbamazepine, trazodone, tricyclic antidepressants, itraconazole, ketoconazole, voriconazole, clarithromycin, rifabutin (dose rifabutin 150 mg every other day† ; monitor for antimycobacterial activity and consider therapeutic drug monitoring), diltiazem, midazolam, felodipine, nifedipine, nicardipine, verapamil, fluticasone, ethinyl estradiol (without ritonavir), norgestimate, norethindrone, atorvastatin, lovastatin, pitavastatin, rosuvastatin, salmeterol, simvastatin, sildenafil, tadalafil, vardenafil, colchicine, quetiapine, bosentan, cyclosporine, sirolimus, tacrolimus.
Decreased concentrations of concomitant medication*: phenytoin, phenobarbital, voriconazole, ethinyl estradiol (with ritonavir).
Increased concentrations of atazanavir with concomitant medication*: clarithromycin.
Decreased concentrations of atazanavir with concomitant medication*: antacids, buprenorphine (do not coadminister atazanavir without ritonavir), carbamazepine, phenobarbital, phenytoin, omeprazole, H2-receptor antagonists, bosentan, voriconazole.
Drug interactions between atazanavir and other antiretrovirals*:
See above for pregnancy and lactation.
Nausea, jaundice (due to unconjugated hyperbilirubinemia), abdominal pain, headache, lipodystrophy, diarrhoea, vomiting, dyspepsia, rash, dizziness, insomnia, peripheral neuropathy.
Potential for dyslipidemia and gastrointestinal effects lower than with other PIs.
*Information from US prescribing information.
†Recommendation from Southern African HIV Clinician Society Guidelines, 2014.