Gilead Sciences Inc. reported 48-week results from Study 461, a trial to evaluate the antiviral activity and safety of Hepsera as a monotherapy or in combination with ongoing lamivudine, compared to continued lamivudine monotherapy in chronic hepatitis B patients with lamivudine-resistant virus and compensated liver function.

Results showed patients with lamivudine-resistant virus who switched to Hepsera monotherapy or added Hepsera to ongoing lamivudine experienced virological, biochemical and serological improvements through 48 weeks. Patients who received Hepsera alone or in combination with lamivudine experienced statistically significant reductions in both serum hepatitis B virus DNA and alanine aminotransferase, compared to patients who received only lamivudine.

Patients treated with lamivudine alone did not show significant virological, biochemical or serological benefit, compared to baseline levels. And results from two Hepsera treatment arms showed that switching to monotherapy with Hepsera achieved similar results to combination therapy in patients with lamivudine-resistant hepatitis B virus.

Hepsera, a nucleotide analogue, was approved in the U.S. in September to treat hepatitis B in adults with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferase or histologically active disease. The product is under review in Canada, the European Union and Australia.

In other news from the meeting:

• Human Genome Sciences Inc., of Rockville, Md., said interim results from an ongoing Phase I trial of Albuferon-alpha showed the product was well tolerated, had a prolonged half-life and was biologically active in adults with chronic hepatitis C. Data were presented on 34 patients who have been treated to date. Albuferon-alpha is a long-lasting recombinant interferon alpha, the company said.

• Ribapharm Inc., of Costa Mesa, Calif., said it will begin Phase II trials of viramidine in the treatment of hepatitis C by the end of the year. The company presented data from several preclinical and Phase I studies. Viramidine is a nucleoside analogue structurally related to ribavirin.

• Schering-Plough Corp., of Kenilworth, N.J., said more than 40 studies with Peg-Intron were presented by clinical investigators, including several studies on Peg-Intron Powder for Injection in combination with Rebetrol (ribavirin) Capsules. Peg-Intron and Rebetol make up an approved pegylated interferon-based combination therapy to treat chronic hepatitis C in patients with compensated liver disease who have not been previously treated with interferon alpha and are at least 18 years old.

• SciClone Pharmaceuticals Inc., of San Mateo, Calif., said Zadaxin in combination with pegylated interferon alpha increased the early virologic response (EVR) rates up to 36 percent in hepatitis C patients who had failed prior therapy. Complete data from a 12-week dose-ranging study showed that groups of nonresponders treated with Zadaxin combination therapy reported positive dose-related EVR rates ranging from 20 percent to 36 percent. Zadaxin is in two Phase III hepatitis C trials in the U.S., and the product has been approved by the ministries of health in more than 30 countries.

• United Therapeutics Corp., of Silver Spring, Md., said the Drug Registration Department of the Israeli Ministry of Health approved Remodulin (treprostinil sodium) Injection for the treatment of primary pulmonary arterial hypertension and pulmonary arterial hypertension associated with connective tissue disorders. The company said about 25 patients are currently being treated with Remodulin in Israel. The FDA approved the drug in May.