Human Genome Sciences, Inc announced it has begun dosing patients in a phase 2 clinical trial of Albuferon (albumin-interferon alpha) in patients with chronic hepatitis C who are naïve to interferon-alpha treatments.
The phase 2 trial is a randomized, open-label, multi-center, parallel-design dose-ranging study to evaluate the safety, tolerability, pharmacology, and optimal dosing of Albuferon.
The phase 2 clinical trial will be conducted in Canada, and will enroll approximately forty patients with hepatitis C virus (HCV) genotype 1. Genotype 1 accounts for nearly seventy percent of all HCV infections in North America and is generally regarded as the most difficult HCV genotype to treat.
A minimum of ten patients will be randomized to each of three dose groups, which will be given two doses of Albuferon administered subcutaneously fourteen days apart. The pharmacodynamic activity of Albuferon will be evaluated based on HCV RNA viral load reductions over a 28-day period of exposure and early virologic response at Day 28. One of the study objectives is to identify a range of active doses that Human Genome Sciences plans to evaluate in a larger 48-week study of Albuferon in combination with ribavirin in patients with HCV genotype 1 who are naïve to interferon treatments.
Interim results of an ongoing phase 1/2 clinical trial of Albuferon in interferon-experienced adults with chronic hepatitis C were presented at the April 2004 Annual Meeting of the European Association for the Study of the Liver (EASL) in Berlin.1 Interim results demonstrate that Albuferon is well tolerated, has a prolonged half-life, and is biologically active. On average, patients participating in the ongoing clinical trial had been treated previously for approximately 68 weeks with regimens containing interferon alpha or pegylated interferon.
Data were presented at the EASL meeting on fifty-one patients who were enrolled under an amendment to the original protocol and were treated with single doses of Albuferon administered subcutaneously at 120 micrograms (mcg), 180 mcg, 240 mcg, 320 mcg, 400 mcg, 500 mcg, or 600 mcg - or with two doses of Albuferon administered subcutaneously fourteen days apart at 400 mcg or 500 mcg. All cohorts treated under the amended protocol showed evidence of biological activity. Viral load levels represent the quantity of hepatitis C virus in the blood, and reductions in viral load are a surrogate marker for clinical benefit. Fifty-five per cent (28/51) of Albuferon-treated patients in the combined single-injection and double-injection cohorts experienced an antiviral response, as demonstrated by reductions in their viral load of 0.5 log or greater at two consecutive time points. Of those experiencing an antiviral response, seventy-nine percent (22/28) experienced reductions of at least 0.9 log units.
Vijayan Balan, M.D., a lead investigator and director, Hepatobiliary Clinic, Division of Transplant Medicine and Division of Gastroenterology and Hepatology, Mayo Clinic Hospital, Phoenix, AZ, said, "Hepatitis C is the most common chronic blood-borne infection in the developed world. It afflicts approximately four million people in the United States alone, about four times the number afflicted by HIV, the virus that causes AIDS. There is a significant need to provide hepatitis C patients with additional treatment options, and Albuferon has looked promising in our initial studies. Further development in interferon-naïve patients is warranted."