Atazanavir (Reyataz) Label Changes Cover Drug Interactions, Kidney Impairment

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Atazanavir (Reyataz) Label Changes Cover Drug Interactions, Kidney Impairment

The U.S. Food and Drug Administration this week announced revisions to the package insert for the protease inhibitor atazanavir (Reyataz), reflecting new information about administration with food, interaction with several drugs, and use by patients with impaired kidney function.

Below is an edited version of the agency’s notification:

The Reyataz (atazanavir) package insert was revised to include information regarding the administration of atazanavir and/or atazanavir/ritonavir with food, proton pump inhibitors, H₂ receptor antagonists, acetaminophen, and fluconazole [Diflucan]. Additionally, dosing information in patients with renal impairment was included.

Please refer to http://www.fda.gov/cder/foi/label/2007/021567s014lbl.pdf for complete labeling. Below are highlight of the major recent changes.

The Dosage and Administration section and Precautions: Drug Interaction Table 11 was updated to include drug interaction information regarding the use of Reyataz and proton pump inhibitors and H₂-receptor antagonists [two classes of drug used to reduce stomach acid production].

The dose recommendations for therapy-naive patients receiving H₂-receptor antagonists or proton pump inhibitors are the following:

• H2-receptor antagonist: The H2-receptor antagonist dose should not exceed a 40 mg dose equivalent of famotidine [Pepcid] twice daily. Reyataz 300 mg and ritonavir 100 mg should be administered simultaneously with, and/or at least 10 hours after, the dose of the H2-receptor antagonist.

• Proton-pump inhibitors: The proton-pump inhibitor dose should not exceed a 20 mg dose equivalent of omeprazole [Prilosec, Losec, Zegerid] and must be taken approximately 12 hours prior to the Reyataz 300 mg and ritonavir 100 mg dose.

The dose recommendations for therapy-experienced patients receiving H2-receptor antagonists or proton pump inhibitors are the following:

• Whenever an H2-receptor antagonist is given to a patient receiving Reyataz with ritonavir, the H2-receptor antagonist dose should not exceed a dose equivalent to famotidine 20 mg twice daily, and the Reyataz and ritonavir doses should be administered simultaneously with, and/or at least 10 hours after, the dose of the H2-receptor antagonist.
• Reyataz 300 mg (one 300-mg capsule or two 150-mg capsules) with ritonavir 100 mg once daily (all as a single dose with food) if taken with an H2-receptor antagonist.

• Reyataz 400 mg (two 200-mg capsules) with ritonavir 100 mg once daily (all as a single dose with food) if taken with both tenofovir and an H2-receptor antagonist.
• Proton-pump inhibitors should not be used in treatment-experienced patients receiving Reyataz.

In addition, the Dosage and Administration section was updated to provide dosing information for patients with renal [kidney] impairment as follows:

For patients with renal impairment, including those with severe renal impairment who are not managed with hemodialysis, no dose adjustment is required for Reyataz. Treatment-naive patients with end stage renal disease managed with hemodialysis should receive Reyataz 300 mg with ritonavir 100 mg. Reyataz should not be administered to HIV-treatment experienced patients with end stage renal disease managed with hemodialysis.

No dose adjustments are needed when Reyataz is co-administered with acetaminophen or fluconazole.

The Clinical Pharmacology section was updated to include the following information:

• Results of a food effect study with Reyataz 300 mg with ritonavir 100 mg with a light meal and high fat meal (see Clinical Pharmacology: Food Effect).

• Results of a study in adult subjects with severe renal impairment, including those on hemodialysis is presented (see Clinical Pharmacology: Special Populations: Impaired Renal Function).

• Results of drug-drug interaction studies with acetaminophen, famotidine, fluconazole, and omeprazole (See Clinical Pharmacology: Table 4: Drug Interactions: Pharmacokinetic Parameters for Atazanavir in the Presence of Coadministered Drugs and Table 5: : Drug Interactions: Pharmacokinetic Parameters for Coadministered Drugs in the Presence of Reyataz).

1/18/08

Source
R Klein and K Struble for the U.S. Food and Drug Administration. HIV/AIDS Update - Reyataz (atazanavir) package insert revisions. Email announcement. January 16, 2008.