Peptech Limited (SYDNEY, Australia) is a clinical-stage biopharmaceutical company dedicated to developing and providing antibody- and peptide-based human therapeutic products for the treatment of inflammatory diseases and cancer. The company announced the initiation of a phase I trial, enrolling up to thirty healthy participants, for its lead compound PN0621 to determine the compound's safety. PN0621, an anti-TNF "domain antibody," is the first to be administered to humans. The dose escalation trial will take place in Sydney and is expected to last for up to 4 months. Final results, after data analysis and review, should be available in late 2007. According to Peptech, PN0621 was more potent than a "leading blockbuster" anti-TNF drug for rheumatoid arthritis (RA) in comparison preclinical animal studies, and production data has confirmed that the drug can be produced cost effectively in large scaled-up quantities at an internationally competitive yield.
The trial participants will each be given a single dose of PN0621 by either intravenous or subcutaneous injection. Subject to confirmation of the safety of the lowest dose, subsequent trial participants will be administered higher doses. Phase I trial information on safety, tolerability, pharmacokinetics, and pharmacodynamics will be used to design phase II trials of PN0621 in the treatment of RA and other inflammatory diseases. The company has already manufactured sufficient quantities of PN0621 for phase II trials, which are scheduled for early 2008.
Domain antibodies are smaller than conventional antibodies but retain their high level of specificity. PN0621 has been engineered to contain fully human constant regions (IgG1, CH 2, and CH 3 effector function domains) and has a molecular weight of 78kDa (about half the size of traditional antibodies), which might provide for increased biodistribution (eg, penetration of diseased joints). Preclinical studies demonstrated favorable safety and toxicology outcomes at dosing up to 100X the predicted human dose. In addition to RA, Peptech has plans to clinically advance PN0621 for ankylosing spondylitis, Crohn's disease, and psoriatic arthritis.
PN0615, Peptech's lead anti-TNF monoclonal antibody, is under preclinical study for the treatment of multiple inflammatory diseases such as RA and Crohn's disease. This antibody is about 2 years behind PN0621 in terms of entry into the clinic, but has already yielded positive preclinical data indicative of impressive potency advantages over its PN0621 as well as marketed products.
Peptech receives royalties from sales of two of three leading anti-TNF therapies: Humira® (Abbott Laboratories) and RemicadeR (Johnson & Johnson/Centocor, Inc).
—A. Techman
E-mail any comments to .