Pharmasset to Develop Clevudine for the Treatment of Chronic Hepatitis B

Pharmasset, Inc. and Bukwang Pharmaceutical Company announced that they have entered into an exclusive license agreement under which Pharmasset will develop and commercialize Clevudine, also known as L-FMAU, for the treatment of chronic hepatitis B virus (HBV) infection in the Americas, Europe, and other select territories. Following is the text of the announcement:

Clevudine is a potent HBV antiviral currently in Phase 3 clinical trials in Korea and has been the subject of earlier stage clinical trials under an Investigational New Drug application filed with the US FDA. The financial terms of the agreement were not disclosed.

Clevudine is an oral, once-daily nucleoside analog drug candidate for the treatment of HBV that was shown to be well tolerated and potent in previously completed clinical studies. Clevudine also demonstrated a sustained therapeutic effect, observed as a prolonged rebound of virus to pretreatment levels, after the cessation of 24 weeks of treatment in clinical trials.

Several advanced-stage clinical trials of Clevudine are ongoing, including a 48-week, Phase 3 clinical trial that is being conducted in Korea in over 200 patients. These individuals are receiving 24 weeks of treatment with 30 mg of Clevudine, followed by 24 weeks of treatment with 10 mg Clevudine.

Two other 24-week Phase 3 clinical trials are being concluded in both HBeAg(+) and HBeAg(-) patients in Korea. Preliminary results of these trials have indicated that Clevudine reduced the HBV viral load to undetectable levels after 24 weeks in 59% and 92% of trial participants, respectively.

Schaefer Price, Pharmasset’s President & CEO, stated, “As new, better therapies are introduced into the HBV market, we believe the market will grow and the standard of care for the treatment of chronic Hepatitis B will evolve into a combination therapy similar to HAART therapy used to combat HIV. Based on the current clinical findings, we believe Clevudine has the potential to be a key component of future combination therapy for chronic HBV. With their different mechanisms of ation against the hepatitis B virus, Clevudine and Racivir, Pharmasset’s Phase 2 drug candidate, have the potential to address this anticipated need for HBV combination therapy.”

Under the terms of the agreement, Pharmasset gained development and commercialization rights to Clevudine, and Bukwang received an option to Racivir for the treatment of chronic Hepatitis B in Korea. Bukwang granted Pharmasset commercialization rights to Clevudine for North, Central and South America, Europe, the Caribbean, and Israel, but has retained rights to certain other countries, excluding those Asian territories that were licensed by Bukwang to Eisai Pharmaceuticals in November 2004.

"We are confident in Pharmasset’s ability to successfully develop Clevudine,” noted Sung-Koo Lee, Bukwang’s President and Representative Director of the Board. “Bukwang and Pharmasset possess the combined expertise required to accelerate the development of Clevudine into a viable, once-daily treatment option for patients chronically-infected with HBV."

Pharmasset has two drugs in Phase 2 clinical trials for the treatment of HIV, Reverset and Racivir, and several other antiviral compounds in advanced preclinical studies.

In 2004, Pharmasset entered into a collaboration agreement with Hoffmann-La Roche for the development and commercialization of PSI-6130 in certain territories for the treatment of hepatitis C. Pharmasset retains proprietary development and commercialization rights to the balance of its clinical and preclinical pipeline.

07/13/05

Source
Pharmasset, Inc. Pharmasset to Develop Clevudine for the Treatment of Chronic Hepatitis B under a License from Bukwang Pharmaceuticals. Press Release. June 27, 2005.