Nelfinavir

It is a nonpeptide protease inhibitor. It is well absorbed and does not require strict food or fluid conditions, although it is usually given with food. Nelfinavir undergoes metabolism by several CYP isozymes. The major metabolite of nelfinavir produced by isoenzyme CYP2C19 has an antiviral activity equal to that of the parent compound, but it achieves plasma concentrations of only 40 percent of those of the parent compound. Nelfinavir is the only protease inhibitor that cannot be boosted by ritonavir, because it is not extensively metabolized by CYP3A. The half-life of nelfinavir is 5 hours. Diarrhea is the most common side effect and can be controlled by loperamide. Like other members of the class, nelfinavir can inhibit the metabolism of other drugs, resulting in required alterations of drug dosage or the prohibition of combined use.hepatic metabolism via CYP3A4 and a short half-life. As an inhibitor of drug metabolism, nelfinavir has been involved in many drug interactions. Adverse effects include diarrhea, which can be dose-limiting. The drug has the most favorable safety profile of the PIs in pregnancy