Sustiva and Telaprevir

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Talk to your doctor before using telaprevir together with efavirenz. Combining these medications may decrease the blood levels of telaprevir, which may reduce its effectiveness in treating hepatitis C. Your doctor may be able to prescribe alternatives that do not interact. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

GENERALLY AVOID: Coadministration with efavirenz may decrease the plasma concentrations of telaprevir. The mechanism is efavirenz induction of CYP450 3A4, the isoenzyme responsible for the metabolic clearance of telaprevir. When telaprevir (750 mg every 8 hours for 10 days) was given in combination with efavirenz (600 mg once daily for 20 days) to 21 study subjects, telaprevir peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) decreased by 9%, 26% and 47%, respectively. Efavirenz Cmax also decreased by 16% and AUC decreased by 7% in the presence of telaprevir, although these changes were not considered significant. When telaprevir (1125 mg every 8 hours) was given in combination with both efavirenz (600 mg once daily) and tenofovir disoproxil fumarate (300 mg once daily) for 7 days to fifteen study subjects, the Cmax, AUC and Cmin of telaprevir decreased by an average of 14%, 18% and 25%, respectively, compared to telaprevir administered alone at 750 mg every 8 hours. When telaprevir was given at a dosage of 1500 mg every 12 hours with the same dosages of efavirenz and tenofovir DF for 7 days, the Cmax, AUC and Cmin of telaprevir was reduced by an average of 3%, 20% and 48%, respectively, compared to telaprevir administered alone at 750 mg every 8 hours. The substantial reduction in trough concentrations of telaprevir during coadministration of efavirenz may lead to virologic failure.

MANAGEMENT: Given the risk of reduced viral susceptibility and resistance development associated with subtherapeutic drug levels, concomitant use of telaprevir with efavirenz should generally be avoided.

Sustiva

Generic Name: efavirenz

Brand name: Sustiva

Synonyms: n.a.

What is Sustiva?

Telaprevir

Generic Name: telaprevir

Brand name: Incivek

Synonyms: Telaprevir (Oral)

What is Telaprevir?