Cobicistat

Cobicistat is a prescription medication used to increase the systemic exposure of atazanavir or darunavir (once-daily dosing regimen) in combination with other antiretroviral agents (ARTs) in the treatment of HIV-1 infection.

• Cobicistat is available under the following different brand names: Tybost.

Common side effects of Cobicistat include:

• nausea,
• rash, and
• yellowing of the skin or eyes (jaundice)

Serious side effects of Cobicistat include:

• hives,
• difficulty breathing,
• swelling of the face, lips, tongue, or throat,
• little or no urination,
• swelling in your feet or ankles,
• tiredness,
• shortness of breath,
• upper stomach pain,
• loss of appetite,
• dark urine,
• clay-colored stools, and
• yellowing of the skin or eyes (jaundice)

Rare side effects of Cobicistat include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors;
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult and pediatric dosage

Tablet

• 150 mg

Pharmacokinetic Enhancer for HIV Treatment

Adult dosage

• Coadministered with atazanavir
  • May use for treatment-naïve or experienced
  • 150 mg orally every day with atazanavir 300 mg orally every day plus other ARTs
• Coadministered with darunavir
  • May use for treatment-naïve or treatment-experienced with no darunavir resistance-associated substitutions
  • 150 mg orally every day with darunavir 800 mg orally every day plus other ARTs

Pediatric dosage

• Coadministration with atazanavir
  • Below 35 kg: Safety and efficacy not established
  • Above 35 kg: Cobicistat 150 mg orally every day plus atazanavir (300 mg orally every day) plus other ARTs
• Coadministration with darunavir
  • Below 40 kg: Safety and efficacy not established
  • Above 40 kg: Cobicistat 150 mg orally every day plus darunavir (800 mg orally every day) plus other ARTs

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Cobicistat has severe interactions with at least 40 other drugs.
• Cobicistat has serious interactions with at least 156 other drugs.
• Cobicistat has moderate interactions with at least 195 other drugs.
• Cobicistat has minor interactions with the following drugs:
  • acetazolamide
  • anastrozole
  • cyclophosphamide
  • ganaxolone
  • ixazomib

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, health questions, or concerns.

Contraindications

• Coadministration of cobicistat with atazanavir or darunavir and the following drugs is contraindicated owing to the potential for serious and/or life-threatening events or loss of therapeutic effect
• Alfuzosin
• Amiodarone
• Carbamazepine, phenobarbital, phenytoin
• Rifampin
• Irinotecan (when administered with atazanavir)
• Lurasidone, pimozide
• Dihydroergotamine, ergotamine, methylergonovine
• Cisapride
• St. John’s wort (Hypericum perforatum)
• Drospirenone/ethinyl estradiol (when administered with atazanavir)
• Lomitapide, lovastatin, simvastatin
• Nevirapine (when administered with atazanavir)
• Sildenafil when administered for pulmonary arterial hypertension
• Indinavir (when administered with atazanavir)
• Triazolam, orally administered midazolam

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Cobicistat?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Cobicistat?”

Cautions

• Cobicistat may cause modest increases in serum creatinine and modest declines in CrCl without affecting renal glomerular function; serum creatinine is more than 0.4 mg/dL from baseline should be closely monitored for renal safety; assess CrCl before administering
• New-onset or worsening renal impairment reported when used with antiretroviral regimens containing tenofovir; do not use with tenofovir if CrCl is less than 70 mL/min
• Assess urine glucose and urine protein at baseline and monitor ClCr, urine glucose, and urine protein when using with tenofovir; monitor serum phosphorus in patients with or at risk for renal impairment
• CYP inducers may lower systemic exposure of cobicistat and atazanavir or darunavir, resulting in loss of virologic response
• Cobicistat is an inhibitor of CYP3A, CYP2D6, p-glycoprotein (P-gp), BCRP, OATP1B1, and OATP1B3; the plasma concentration of drugs that are substrates of the aforementioned isoenzymes or transporters may be increased if coadministered with cobicistat
• Antiretrovirals that are not recommended
• The following are NOT recommended in combination with cobicistat because dosing recommendations for the combinations have not been established
• Coadministration may result in decreased plasma concentrations of the antiretroviral agents, leading to loss of therapeutic effect and development of resistance
• More than 1 antiretroviral that requires pharmacokinetic enhancement (i.e., 2 protease inhibitors or a protease inhibitor in combination with elvitegravir)
• Darunavir in combination with efavirenz, nevirapine, or etravirine
• Atazanavir in combination with etravirine
• Atazanavir in combination with efavirenz in treatment-experienced patients
• Darunavir 600 mg twice daily
• Other HIV-1 protease inhibitors, including fosamprenavir, saquinavir, or tipranavir
• Stribild fixed-dose combination tablets (elvitegravir, cobicistat, emtricitabine, tenofovir) are not recommended because cobicistat is a component of Stribild
• Cobicistat in combination with lopinavir/ritonavir or regimens containing ritonavir is not recommended, owing to similar effects of cobicistat and ritonavir on CYP3A

Pregnancy and Lactation

• Coadministration with darunavir or atazanavir is not recommended during pregnancy
• In a clinical trial of individuals taking cobicistat coadministered with darunavir, exposures of cobicistat and darunavir were substantially lower during the second and third trimesters of pregnancy
• Refer to the prescribing information of darunavir and atazanavir about pregnancy
• ART pregnancy registry
  • Pregnancy exposure registry that monitors fetal outcomes in individuals exposed to the drug during pregnancy
  • Encourage to register patients by calling Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263
• Contraception
  • Cobicistat interacts with certain oral contraceptives
• Lactation
  • There is no information regarding the presence of cobicistat in human milk, the effects on the breastfed infant, or the effects on milk production
  • The Centers for Disease Control and Prevention do not recommend HIV-infected mothers breastfeed their infants due to the potential risk for postnatal transmission of HIV