Fosamprenavir and Isentress

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 raltegravir together with fosamprenavir. Combining these medications may reduce the blood levels and effects of both medications. This may make them less effective in the treatment of HIV. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. 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.

MONITOR: Coadministration of fosamprenavir (with or without ritonavir) and raltegravir may decrease the plasma concentrations of both amprenavir and raltegravir. The mechanism of interaction has not been described. In 14 study subjects, administration of fosamprenavir 1400 mg twice a day (under fasting conditions) in combination with raltegravir 400 mg twice a day for 14 days decreased the amprenavir peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) by 27%, 36% and 43%, respectively. When the same dosages were given without regards to food, amprenavir Cmax, AUC and Cmin decreased by 15%, 17% and 32%, respectively. In 14 study subjects, administration of fosamprenavir 700 mg plus ritonavir 100 mg twice a day (under fasting conditions) in combination with raltegravir 400 mg twice a day for 14 days decreased the amprenavir Cmax, AUC and Cmin by 14%, 17% and 20%, respectively. When the same dosages were given without regards to food, amprenavir Cmax, AUC and Cmin decreased by 15%, 17% and 32%, respectively. In 13 study subjects, administration of fosamprenavir 1400 plus ritonavir 100 mg once a day (under fasting conditions) in combination with raltegravir 400 mg twice a day for 14 days decreased the amprenavir Cmax, AUC and Cmin by 18%, 24% and 50%, respectively. When the same dosages were given without regards to food, amprenavir Cmax and AUC increased by 27% and 13%, respectively, but the Cmin decreased by 17%.

MANAGEMENT: Caution is advised if fosamprenavir is prescribed in combination with raltegravir. Appropriate dosages of the combination with respect to safety and efficacy have not been established.

Fosamprenavir

Generic Name: fosamprenavir

Brand name: Lexiva, Telzir

Synonyms: n.a.

What is Fosamprenavir?

Isentress

Generic Name: raltegravir

Brand name: Isentress, Isentress HD

Synonyms: n.a.

What is Isentress?