Saquinavir and Viracept (Nelfinavir Oral Powder)

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.

Using saquinavir together with nelfinavir may increase the effects of saquinavir. Contact your doctor if you experience sore throat, headache, rash, increased urination or extreme thirst, easy bruising or bleeding, fever, chills, cough, nausea, stomach pain, loss of appetite, dark urine, clay-colored stools, or jaundice (yellowing of the skin or eyes). If your doctor does prescribe these medications together, you may need a dose adjustment or special test 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.

GENERALLY AVOID: Coadministration with nelfinavir may significantly increase the bioavailability of saquinavir from both the hard gelatin capsule (HGC) and soft gelatin capsule (SGC) formulations. The mechanism is nelfinavir inhibition of CYP450 3A4, the isoenzyme responsible for the metabolic clearance of saquinavir. In six HIV+ patients stabilized on their antiretroviral regimen, addition of nelfinavir (750 mg orally three times a day for 2 days) resulted in mean peak plasma concentration (Cmax) and 8-hour area under the concentration-time curve (AUC) for saquinavir (HGC 600 mg three times a day) that were approximately five times those at baseline. In 14 HIV+ patients, coadministration of nelfinavir (750 mg orally three times a day for 4 days) and saquinavir (SGC 1200 mg single dose) yielded increases in saquinavir Cmax and AUC of 179% and 392%, respectively, according to the product labelings. In 18 healthy volunteers, simultaneous administration of nelfinavir (750 mg single oral dose) decreased the clearance of saquinavir (SGC 800 mg single dose) 10-fold compared to when saquinavir was administered alone. Saquinavir had negligible effect on the pharmacokinetics of nelfinavir. In addition, in 12 HIV+ patients administered multiple doses of saquinavir-ritonavir (1000 mg-100 mg twice a day) with nelfinavir (1250 mg twice a day), there were negligible increases in the AUC and Cmax of saquinavir of 13% and 9%, respectively. There were also negligible changes in the AUC and Cmax of nelfinavir, with a reduction of 6% and 5%, respectively.

MANAGEMENT: Due to a high degree of interpatient variability in saquinavir bioavailability, the interaction with nelfinavir may benefit some patients while exposing others to excessively high saquinavir levels and potential toxicity. The combination of ritonavir-boosted saquinavir and nelfinavir is generally not recommended; appropriate dosages for the combination with respect to safety and efficacy have not been established. Patients receiving the combination should be closely monitored for toxicity, including elevations in liver function tests and serum creatinine phosphokinase and neutropenia, and the dosage(s) adjusted as necessary.

Saquinavir

Generic Name: saquinavir

Brand name: Invirase, Fortovase

Synonyms: n.a.

What is Saquinavir?

Viracept (Nelfinavir Oral Powder)

Generic Name: nelfinavir

Brand name: Viracept

Synonyms: Viracept

What is Viracept (Nelfinavir Oral Powder)?