Last Updated: April 16, 2019; Last Reviewed: April 16, 2019
Cobicistat (COBI, Tybost)
|Cobicistat (COBI, Tybost)
For additional information see Drugs@FDA: https://www.accessdata.fda.gov/scripts/cder/daf/
|Tablet: 150 mg
Fixed-Dose Combination Tablets:
- [Evotaz] Atazanavir 300 mg/cobicistat 150 mg
- [Genvoya] Elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir alafenamide (TAF) 10 mg
- [Prezcobix] Darunavir 800 mg/cobicistat 150 mg
- [Stribild] Elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate (TDF) 300 mg
- [Symtuza] Darunavir 800 mg/cobicistat 150 mg/emtricitabine 200 mg/TAF 10 mg
||Selected Adverse Events
|Cobicistat is a Pharmacokinetic Enhancer:
Use of Cobicistat-Containing Drugs in Children and Adolescents
- The only use of cobicistat is as a pharmacokinetic (PK) enhancer (boosting agent) for certain protease inhibitors (PIs) and integrase inhibitors. Cobicistat is not interchangeable with ritonavir.
Not Food and Drug Administration (FDA)-Approved for Use in Children and Adolescents Aged <18 Years:
FDA-Approved for Use in Children and Adolescents Weighing ≥25 kg:
FDA-Approved for Use in Children and Adolescents Aged ≥12 and Weighing ≥35kg:
- Cobicistat alone (as Tybost)
- Some members of the Panel on Antiretroviral Therapy and Medical Management of Children Living with HIV (the Panel) regard the above agents as potentially appropriate for use in certain children aged <18 years and weighing ≥35 kg. An expert in pediatric HIV infection should be consulted before using these drugs in these patients. See the atazanavir and darunavir sections for additional information.
Adult (Aged ≥18 Years) Dose
- The Panel recommends using Stribild only in patients with sexual maturity ratings of 4 or 5.
Cobicistat Must be Administered as:
Doses for Cobicistat and Coadministered Antiretroviral Drugs
- The fixed-dose combination (FDC) tablets Stribild, Genvoya, or Symtuza, which are complete regimens and should not be administered with any other antiretroviral (ARV) drugs; or
- The tablet Tybost, which should be administered at the same time as atazanavir or darunavir at the doses listed in the table below and used in combination with other ARV drugs; or
- The FDC tablets Evotaz (which also contains atazanavir) or Prezcobix (which also contains darunavir). Both FDC tablets should be administered with food and in combination with other ARV drugs.
||Coadministered Agent Dose
|150 mg orally once daily
||As part of Stribild, Genvoya, or Symtuza
||Treatment-naive or treatment-experienced, with virus that is susceptible to all ARV drug components of Stribild, Genvoya, or Symtuza
|150 mg orally once daily
||Atazanavir 300 mg (coformulated as Evotaz or given as a separate drug) given orally once daily
||Treatment-naive or treatment-experienced
|150 mg orally once daily
||Darunavir 800 mg (coformulated as Prezcobix or given as a separate drug) given orally once daily
||Treatment-naive or treatment-experienced, with no darunavir-associated resistance mutations
- Cobicistat is an inhibitor of renal tubular transporters of creatinine. This increases serum creatinine and reduces estimated glomerular filtration rate, with no change in glomerular function.
- Cobicistat 150 mg is not interchangeable with ritonavir, but it has a PK boosting effect that is comparable to ritonavir 100 mg.
- Drug interactions may differ between ritonavir and cobicistat, because cobicistat is a stronger P-glycoprotein inhibitor and lacks some of the induction effects of ritonavir.
- Genvoya, Stribild, and Symtuza are approved for use in treatment-naive patients. They can also be used to replace the current ARV regimen in patients who have been virologically suppressed (HIV RNA <50 copies/mL) on a stable ARV regimen for at least 6 months with no history of treatment failure and no known substitutions associated with resistance to the individual components of these single-tablet regimens.
- Do not administer cobicistat with ritonavir or with FDC tablets that contain cobicistat.
- Not recommended for use with more than one ARV drug that requires PK enhancement (e.g., elvitegravir used in combination with a PI).
- Use with PIs other than once-daily atazanavir 300 mg or darunavir 800 mg is not recommended.
- Patients with a confirmed increase in serum creatinine >0.4 mg/dL from baseline should be closely monitored for renal safety.
- When using cobicistat in combination with TDF, monitor serum creatinine, urine protein, and urine glucose at baseline and every 3 months to 6 months while the patient is receiving therapy (see Table 15i). In patients who are at risk of renal impairment, serum phosphate should also be monitored.
- When using cobicistat in combination with other ARV drugs, or when using FDC tablets that contain cobicistat, see other drug sections for special instructions and additional information about the individual drug components (e.g., atazanavir, darunavir, elvitegravir, TDF, TAF).
Cobicistat Dosing in Patients with Renal Impairment:
- Cobicistat is a strong inhibitor of cytochrome P450 (CYP) 3A4 and a weak inhibitor of CYP2D6.
- Stribild should not be initiated in patients with estimated creatinine clearance (CrCl) <70 mL/min and should be discontinued in patients with estimated CrCl <50 mL/min. The dose adjustments required for emtricitabine and TDF in these patients cannot be achieved with an FDC tablet.
- Neither Genvoya nor Symtuza should be initiated in patients with estimated CrCl <30 mL/min.
- Stribild, Genvoya, and Symtuza should not be used in patients with severe hepatic impairment.