Reyataz is approved for HIV treatment

The Food and Drug Administration has approved Reyataz (atazanavir sulfate), a protease inhibitor, to be used in combination with other antiretroviral agents for the treatment of patients with HIV infection.

The approval permits patient access to a once- a-day protease inhibitor. The recommended dose of Reyataz is 400 mg (two 200 mg capsules) once daily with food.

The FDA based its approval of Reyataz on data from two Phase 2 48-week trials and from 24 to 48-week data from Phase 3 studies. Trial results showed a decrease in viral load (the amount of HIV-1 virus circulating in plasma) and an increase in CD4 cell counts (a measure of immune cells created by the body) in patients taking Reyataz in combination with other antiretroviral agents. These treatment benefits were observed both in patients who had not been previously treated and in patients who had previously received other antiretroviral therapy.

A significant safety concern commonly observed with the use of protease inhibitors is hyperlipidemia. Reyataz appears to have minimal impact on lipid parameters such as triglycerides and cholesterol, the FDA said.

The most common laboratory abnormality observed with the use of Reyataz is hyperbilirubinemia (abnormally high amounts of bilirubin, an orange-yellow pigment in the bile that forms as a product of hemoglobin; excess amounts in the blood produce the yellow appearance observed in jaundice) in the blood.

This laboratory abnormality resulted in the clinical adverse event of jaundice (yellowing of the skin) or scleral icterus (yellowing of the eyes) in 15% to 24% of subjects taking Reyataz. This abnormality was shown to be reversible upon discontinuation of the drug. Hyperbilirubinemia with Reyataz did not appear to be associated with an increased risk of liver injury.

The most frequently reported adverse events among patients in the clinical trials were nausea, infection, headache, vomiting, diarrhea, abdominal pain, somnolence (drowsiness), insomnia, and fever.

Currently, there are six other protease inhibitors approved by FDA for the treatment of HIV infection. These medications work at the final stages of viral replication and attempt to prevent HIV from making new copies of itself by interfering with the HIV protease enzyme. As a result, the new copies of HIV are not able to infect new cells.

Reyataz is manufactured by Bristol-Myers Squibb Company of Princeton, NJ.