What is Atazanavir (Reyataz)?
Atazanavir is an HIV Protease Inhibitor (PI) drug, active against both mutant and wild-type HIV-1. It is used in the treatment of HIV-1 infection in combination with other antiretroviral drugs, usually including low-dose ritonavir. This drug is not active against HIV-2. It works by inhibiting HIV protease function, potently blocking the formation of mature virions.
Atazanavir is indicated as part of a combination drug regimen for the treatment of HIV-1 infection. This can be used as post-exposure prophylaxis for HIV following occupational exposure. The medication oral capsules should not be opened and must be swallowed whole. An oral powder is also available. Dosing instructions and considerations are given in detail in the package insert. Atazanavir can be used in adults, children, and infants three months and older weighing 5 kg or more
In patients with hepatic dysfunction, Atazanavir requires dose reduction, and the drug should not be used in patients with severe hepatic impairment. As described in the package insert, patients with a pre-existing liver condition or with Hepatitis B virus (HBV) or Hepatitis C virus (HCV) co-infection should be closely monitored. Patients with renal impairment do not require dosage adjustments, except for those receiving hemodialysis.
Atazanavir is contraindicated in patients with hypersensitivity to the drug, and in patients with severe liver dysfunction (Child-Pugh Class C), or when combined with ritonavir in patients with moderate liver impairment. This medicine is contraindicated for use with certain medications listed in the package insert.
Atazanavir Side Effects
Atazanavir can heart rhythm side effects as well as serious liver effects.
Other potential side effects include:
- renal calculi,
- jaundice, rash,
- fat distribution
A complete list of potential adverse effects is provided in the package insert.
Atazanavir should be used with caution in the presence of cardiac AV block, as it may prolong the PR interval in some patients. This medication should be used with caution in hemophiliacs due to increased bleeding risk.
All patients who test positive for HIV infection should be screened for comorbid HBV and HCV infection. Co-infected patients should be started on an antiretroviral regimen targeting co-infected viruses, regardless of CD4 counts or viral loads. Current HIV treatment guidelines outline drug regimens and prescribing considerations.
Since Atazanavir is associated with a large number of drug-drug interactions, patients should pay close attention to details in the package insert.
Pregnancy & Lactation
Highly active retroviral combination treatment should be used in all pregnant women, regardless of viral load and CD4 count. Data from the Antiretroviral Pregnancy Registry do not associate atazanavir with any increase in risk of overall major birth defects compared to baseline. The drug is excreted in the breast milk. The CDC recommends that all HIV positive women, treated or untreated, avoid breastfeeding to prevent vertical transmission of the virus.
In the case of an overdose, there is no specific treatment. Atazanavir is not removed by hemodialysis. Patients should be provided with supportive care and be closely monitored.
Alternative Brand Names
Atazanavir is also available under the brand name Reyataz.