FDA Notifications

FDA studies private sector patient information

The FDA has announced the findings from a 2001 study designed to assess the extent and usefulness of private sector prescription information patients receive when filling their prescriptions. Study results show approximately 89% of patients received written information about the drugs prescribed for them. The FDA commissioned the study to evaluate the adequacy of private sector prescription drug information given to patients. A federal goal is for 75% of patients obtaining new prescriptions by the year 2000 receive useful written information. The study, conducted by the National Association of Boards of Pharmacy to assess the receipt and usefulness of patient information, reveals that 89% of patients received written information. Although the 89% figure surpasses the goal of 75%, the overall usefulness of information provided, as measured by eight objective consensus-based criteria, was about 50%. The scores for individual criteria varied, with the highest scores (greater than 90%) showing that the information distributed was scientifically accurate, up to date, and nonpromotional.

New treatment approved for chronic hepatitis B

The FDA has approved Hepsera (adefovir dipivoxil) tablets for the treatment of chronic hepatitis B in adults with evidence of active viral replication and either elevations in serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST), or histologically active disease.

Chronic hepatitis B is a serious disease caused by a virus that attacks the liver. The virus, which is called hepatitis B virus (HBV), can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death. According to the Centers for Disease Control and Prevention, approximately 1.25 million Americans are chronically HBV-infected.

Hepsera slows the progression of chronic hepatitis B by interfering with viral replication and causing DNA chain termination after its incorporation into viral DNA. The FDA said it based its approval of Hepsera on the results of two randomized, double-blind, placebo-controlled studies. At week 48 of the studies, 53% of patients receiving Hepsera in one study and 64% of patients in the other study showed significant improvement in the liver inflammation caused by HBV compared to 25% and 35% of patients receiving placebo.

A statistically significant improvement in the degree of liver fibrosis (scarring) was observed in the patients who received Hepsera. Moreover, Hepsera has been shown to be effective in treating patients with clinical evidence of HBV that is resistant to another approved antiviral therapy called lamivudine. The major adverse events associated with the use of Hepsera include severe, acute exacerbation of hepatitis B after discontinuation of Hepsera and kidney toxicity.

Patients who have discontinued other approved products for the treatment of chronic hepatitis B also have experienced severe, acute exacerbation of hepatitis. This adverse event occurred in up to 25% of clinical trial participants after discontinuation of Hepsera. The labeling for Hepsera states that patients who discontinue Hepsera should be monitored at repeated intervals over a period of time for hepatic function.

Kidney toxicity was reported in patients at risk of or having underlying kidney dysfunction. In addition, there is a theoretical concern associated with Hepsera that HIV resistance could emerge in chronic hepatitis B patients with unrecognized or untreated HIV infection.

Prior to initiating Hepsera therapy, HIV antibody testing should be offered to all patients. Hepsera (adefovir 10 mg ) has not been shown to suppress HIV RNA in patients. Gilead Sciences Inc., of Foster City, CA, is the sponsor of Hepsera.