New FDA Approvals

The following drugs have received final approval from the Food and Drug Administration (FDA):

Adefovir dipivoxil (Hepsera) by Gilead Sciences. The FDA has approved antiviral adefovir dipivoxil (Hepsera) for the treatment of chronic hepatitis B virus (HBV) in adults with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease.

Adefovir dipivoxil, administered as an oral 10 mg tablet, is the first nucleotide analogue to receive FDA approval for the treatment of chronic hepatitis B. Adefovir dipivoxil slows the progression of chronic hepatitis B by interfering with viral replication and causing DNA chain termination after its incorporation into viral DNA. Adefovir dipivoxil has also been shown to be effective in treating patients with clinical evidence of HBV that is resistant to lamivudine.

The major adverse events associated with the use of adefovir dipivoxil include severe, acute exacerbation of hepatitis B after discontinuation of the drug, and kidney toxicity. This adverse event occurred in up to 25% of clinical trial participants. Therefore, the labeling for adefovir dipivoxil states that patients who discontinue the drug therapy should be monitored at repeated intervals over a period of time for hepatic function.

Gilead says the wholesaler acquisition cost for adefovir dipivoxil in the United States will be $440 for a bottle of 30 tablets, or one month of therapy. The company also has established a U.S. Patient Assistance Program for people who do not have insurance or cannot afford to pay for treatment. For more information, call (800) GILEAD-5 or (650) 574-3000.

Eplerenone tablets (Inspra) by Pharmacia. The FDA has granted marketing approval for eplerenone tablets (Inspra), the first agent designed to selectively block aldosterone, for the treatment of high blood pressure. Clinical trials in approximately 3,000 patients demonstrated that eplerenone tablets are effective in lowering high blood pressure, both alone and in combination with other antihypertensive therapies, and are generally well-tolerated.