Cobicistat Versus Ritonavir: Similar Pharmacokinetic Enhancers But Some Important Differences.

Article Details

Citation

Tseng A, Hughes CA, Wu J, Seet J, Phillips EJ

Cobicistat Versus Ritonavir: Similar Pharmacokinetic Enhancers But Some Important Differences.

Ann Pharmacother. 2017 Nov;51(11):1008-1022. doi: 10.1177/1060028017717018. Epub 2017 Jun 19.

PubMed ID
28627229 [ View in PubMed
]
Abstract

OBJECTIVE: To describe properties of cobicistat and ritonavir; compare boosting data with atazanavir, darunavir, and elvitegravir; and summarize antiretroviral and comedication interaction studies, with a focus on similarities and differences between ritonavir and cobicistat. Considerations when switching from one booster to another are discussed. DATA SOURCES: A literature search of MEDLINE was performed (1985 to April 2017) using the following search terms: cobicistat, ritonavir, pharmacokinetic, drug interactions, booster, pharmacokinetic enhancer, HIV, antiretrovirals. Abstracts from conferences, article bibliographies, and product monographs were reviewed. STUDY SELECTION AND DATA EXTRACTION: Relevant English-language studies or those conducted in humans were considered. DATA SYNTHESIS: Similar exposures of elvitegravir, darunavir, and atazanavir are achieved when combined with cobicistat or ritonavir. Cobicistat may not be as potent a CYP3A4 inhibitor as ritonavir in the presence of a concomitant inducer. Ritonavir induces CYP1A2, 2B6, 2C9, 2C19, and uridine 5'-diphospho-glucuronosyltransferase, whereas cobicistat does not. Therefore, recommendations for cobicistat with comedications that are extrapolated from studies using ritonavir may not be valid. Pharmacokinetic properties of the boosted antiretroviral can also affect interaction outcome with comedications. Problems can arise when switching patients from ritonavir to cobicistat regimens, particularly with medications that have a narrow therapeutic index such as warfarin. CONCLUSIONS: When assessing and managing potential interactions with ritonavir- or cobicistat-based regimens, clinicians need to be aware of important differences and distinctions between these agents. This is especially important for patients with multiple comorbidities and concomitant medications. Additional monitoring or medication dose adjustments may be needed when switching from one booster to another.

DrugBank Data that Cites this Article

Drugs
Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
CobicistatCytochrome P450 3A5ProteinHumans
Yes
Inhibitor
Details
CobicistatCytochrome P450 3A7ProteinHumans
Yes
Inhibitor
Details
Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
CobicistatCytochrome P450 3A4ProteinHumans
No
Substrate
Details
RitonavirCytochrome P450 2C19ProteinHumans
No
Inducer
Details
RitonavirUDP-glucuronosyltransferases (UGTs) (Protein Group)Protein groupHumans
No
Inducer
Details
Drug Interactions
DrugsInteraction
Atazanavir
Tenofovir disoproxil
The serum concentration of Atazanavir can be decreased when it is combined with Tenofovir disoproxil.
Atazanavir
Tenofovir alafenamide
The serum concentration of Atazanavir can be decreased when it is combined with Tenofovir alafenamide.
Atazanavir
Tenofovir
The serum concentration of Atazanavir can be decreased when it is combined with Tenofovir.
Elvitegravir
Atazanavir
The serum concentration of Elvitegravir can be increased when it is combined with Atazanavir.