Drug Interactions between Sustiva and telaprevir
This report displays the potential drug interactions for the following 2 drugs:
- Sustiva (efavirenz)
- telaprevir
Interactions between your drugs
efavirenz telaprevir
Applies to: Sustiva (efavirenz) and telaprevir
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.
References
- "Product Information. Incivek (telaprevir)." Vertex Pharmaceuticals (2011):
Drug and food interactions
efavirenz food
Applies to: Sustiva (efavirenz)
ADJUST DOSING INTERVAL: Administration with food increases the plasma concentrations of efavirenz and may increase the frequency of adverse reactions. According to the product labeling, administration of efavirenz capsules (600 mg single dose) with a high-fat/high-caloric meal (894 kcal, 54 g fat, 54% calories from fat) or a reduced-fat/normal-caloric meal (440 kcal, 2 g fat, 4% calories from fat) was associated with mean increases of 39% and 51% in efavirenz peak plasma concentration (Cmax) and 22% and 17% in systemic exposure (AUC), respectively, compared to administration under fasted conditions. For efavirenz tablets, administration of a single 600 mg dose with a high-fat/high-caloric meal (approximately 1000 kcal, 500-600 kcal from fat) resulted in a 79% increase in mean Cmax and a 28% increase in mean AUC of efavirenz relative to administration under fasted conditions.
MANAGEMENT: Efavirenz should be taken on an empty stomach, preferably at bedtime. Dosing at bedtime may improve the tolerability of nervous system symptoms such as dizziness, insomnia, impaired concentration, somnolence, abnormal dreams and hallucinations, although they often resolve on their own after the first 2 to 4 weeks of therapy . Patients should be advised of the potential for additive central nervous system effects when efavirenz is used concomitantly with alcohol or psychoactive drugs, and to avoid driving or operating hazardous machinery until they know how the medication affects them.
References
- "Product Information. Sustiva (efavirenz)." DuPont Pharmaceuticals PROD (2001):
telaprevir food
Applies to: telaprevir
ADJUST DOSING INTERVAL: Food significantly enhances the oral bioavailability of telaprevir. When given with a meal containing 533 kcal and 21 g fat, telaprevir systemic exposure (AUC) increased by 237% compared to administration under fasting conditions. The type of meal also affects the exposure to telaprevir. Relative to fasting, telaprevir AUC increased by approximately 117% with a low-fat meal (249 kcal; 3.6 g fat) and 330% with a high-fat meal (928 kcal; 56 g fat). In Phase 3 clinical trials, telaprevir doses were administered within 30 minutes of completing a meal or snack containing approximately 20 grams of fat.
MANAGEMENT: Telaprevir should be administered with food containing approximately 20 grams of fat. Patients should be advised that the fat content of the meal or snack is critical to the absorption of telaprevir. Food taken with telaprevir should be ingested within 30 minutes prior to each dose. Examples of some foods that could be taken with telaprevir include: bagel with cream cheese; half cup of nuts; 3 tablespoons of peanut butter; 1 cup of ice cream; 2 ounces of American or cheddar cheese; 2 ounces of potato chips; or half cup of trail mix.
References
- "Product Information. Incivek (telaprevir)." Vertex Pharmaceuticals (2011):
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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