Anti-HIV Effects of Viracept Persist During Long Periods of Combination Therapy

Agouron Pharmaceuticals reported that the profound anti-HIV effectsof its protease inhibitor nelfinavir mesylate (Viracept), when taken incombination with other anti-HIV drugs, continue to be observed after 10months of treatment. Nelfinavir was recently cleared for marketing by theFDA.

At the Tenth International Conference on Anti-viral Research (ICAR)meeting in Atlanta, Agouron senior clinical scientist Dr. Sharon Chapmanprovided an update on results from a key clinical trial of nelfinavir takenin combination with zidovudine (AZT [Retrovir]) and lamivudine (3TC).

After 10 months of treatment, HIV remained below the lower limit ofsensitivity (1,200 viral copies per milliter) of the assay (bDNA) in theplasma of 87% of 74 patients receiving the recommended dose of nelfinavir(750 mg three times daily) for use in the three-drug combination. CD4+T-cells continued to rise in these patients over the 10 months of treatmentto a mean increase of 173 cells.

In a subgroup of 12 patients with advanced disease who had pretreatmentCD4+ T-cell counts of 50 or below and who received the recommended doseof nelfinavir, mean reductions in plasma HIV were 2.2 log 10 (more than99%), with HIV falling below the assay sensitivity limit (1,200 viral copiesper milliliter) in 11 of 12 patients.

In clinical studies of nelfinavir, the most commonly observed adverseevent of moderate or greater severity was diarrhea, which was generallycontrolled with over-the-counter medications.