Atazanavir is an anti-HIV medication.  It is in a category of HIV medicinces called protease inhibitors.  Atazanavir prevents cells infected by HIV from producing new virus.  This reduces the amount of virus in your blood.  It is available only through the Expanded Access Program in Canada at this time (January 2003)

What is already known about Atazanavir?

Information from clinical trials conducted thus far suggest that atazanavir will only need to be taken once a day.  The drug will likely be studied further at a dose of 400 mg once daily.

Like other protease inhibitors, atazanavir might interact with other medications, including those to treat HIV.  It is important that your physician and/or the research nurse or study investigator be aware of all drugs you are taking, including those you buy without a prescription.

What are the side effects?

Atazanavir can increase levels of bilirubin, a pigment found in the liver.  Increased bilirubin can cause the skin, nails, and the whites of the eyes to appear yellowish/brown.  Incrased bilirubin can also be a sign of liver damage.  However, in clinical trials, an increase in bilirubin has not been associated with any other signs of liver damage.  Other possible side effects of atazanavir include headaches, pain/tingling in the arms and legs, abdominal discomfort and rash.

Atazanavir may not increase fat levels in the blood like other protease inhibitors.  There were no increases in triglycerirdes, or "bad" LDL cholesterol in clinical studies.  There were, however, significant increases in HDL cholesterol, which can help reduce the risk of heart disease.  It is still not known if atazanavir can cause body-shape changes, such as an increase in fat around the gut or a loss of fat in the arms, legs or face.  It is also not known if HIV-positive people who continue taking atazanavir for a long period of time will be able to keep their cholesterol and triglyceride levels low.

Who should not take atazanvir?

It is not known whether atazanavir will harm an unborn child.  It is not known whether atazanavir passes into breast milk and what effect it may have on a nursing baby.