Treatment Briefs

Nelfinavir: Twice Daily Use and New Formulation

Nelfinavir (Viracept), Agouron's protease inhibitor that was initially approved at a dose of 750 mg (three 250 mg tablets) three times each day, has become easier to take. Late in 1999, the FDA approved a dose of 1250 mg (five 250 mg tablets) twice daily. The change was based on a clinical trial comparing the two doses of nelfinavir plus d4T and 3TC. Both arms had similar decreases in viral load and increases in CD4 counts, as well as similar rates of diarrhea (14 to 18 percent), a common side effect of nelfinavir.

Agouron has also announced that the FDA approved a film-coated nelfinavir tablet. Previously, there were problems with the tablets breaking, sometimes while being swallowed. The new coating should make the tablet easier to take.

Glaxo Wellcome has issued a warning about potential safety concerns with Agenerase (amprenavir) Oral Solution. The oral solution contains a significant amount of propylene glycol, which some people cannot metabolize sufficiently, leading to possible adverse events including seizures, stupor, lactic acidosis, rapid heart rate, kidney toxicity, and hemolysis (a loss of red blood cells). Because of this, Glaxo has changed the drug's package insert to include the following:

"Because of the potential risk of toxicity from the large amount of the excipient propylene glycol, Agenerase Oral Solution is contraindicated in infants and children below the age of 4 years, pregnant women, patients with hepatic or renal failure, and patients treated with disulfiram [Antabuse] or metronidazole [Flagyl]."

In general, Glaxo says, the oral solution should only be used when amprenavir capsules or other protease inhibitors are not a viable option. And if it is used, patients should be closely monitored for toxicities and should not use alcohol.

Back to the GMHC Treatment Issues Spring 2000 contents page.