Enzon Pharmaceuticals, Inc. reported that Peg-Intron is now available in Japan for use in combination with Rebetol (ribavirin) capsules for the treatment of chronic hepatitis C. Peg-Intron and Rebetol are marketed worldwide by Schering-Plough Corporation.

Peg-Intron and Rebetol combination therapy is the first and only pegylated interferon-based combination therapy approved in Japan. An estimated 1 to 2 million Japanese are chronically infected with hepatitis C. Peg-Intron is a longer-acting form of Intron A (interferon alfa-2b, recombinant) Injection that uses proprietary PEG technology developed by Enzon.

Under the company's licensing agreement with Schering-Plough, Enzon is entitled to royalties on worldwide sales of Peg-Intron. Schering-Plough holds an exclusive worldwide license to Peg-Intron. In October 2004, Peg-Intron received marketing approval from the Ministry of Health, Labour and Welfare (MHLW) following a priority review. The product became available on December 8, 2004 upon National Health Insurance Reimbursement Price Listing.

In Japan, Peg-Intron is indicated in patients chronically infected with hepatitis C virus (HCV) genotype 1 (genotype 1a or 1b) and high viral load. HCV genotype 1 is considered the most difficult-to-treat form of hepatitis C and is the most common form in Japan, accounting for approximately 60 per cent of all HCV infections there. Peg-Intron is the only peginterferon product approved in Japan for which a blood test is not required before every injection.

Hepatitis C is the leading cause in Japan of chronic liver disease, cirrhosis, and hepatocellular carcinoma, which is associated with more than 30,000 deaths there annually. Hepatitis C is the most common reason for liver transplant in major world markets, including Japan, according to the World Health Organization (WHO).