By Debbie Strickland

Special to BioWorld Today

Genzyme General acquired a fellow Cambridge, Mass., biotechnology firm, Peptimmune Inc., gaining a program for treating pemphigus vulgaris as a lead indication for a potentially much broader autoimmune disease therapeutic platform.

"We're very interested in developing treatments to treat genetic diseases with unmet medical needs," said Genzyme spokeswoman Caren Arnstein, noting the patient population for pemphigus - which has a higher prevalence in the Ashkenazi Jewish population - is similar to that for Genzyme's enzyme therapies for Gaucher's disease.

Characterized by severe and potentially fatal blistering of the skin and mucous membranes, pemphigus affects 10,000 to 15,000 people in the U.S., Europe and Japan. The disease stems from development of antibodies to desmoglein-3, a protein essential for the attachment of skin cells. In the presence of these antibodies, the skin blisters and sloughs off. The only available therapies are chronic high-doses of steroids and immunosuppresants, which have significant side effects and limited efficacy.

Peptimmune has derived several peptides from desmoglein-3 as potential therapies for pemphigus and is testing them preclinically; Genzyme expects to begin clinical trials in 2000.

Genzyme General is a division of Genzyme Corp. Terms of the acquisition were not disclosed.

"Pemphigus is the ideal disease to test whether or not this works," said Jim Rasmussen, Peptimmune's chief scientific officer and former vice president of research and development at Genzyme. "The disease has some clear, easily measured clinical endpoints, and for those reasons, this is really the best autoimmune disease to test whether you can tolerize the patients' T cells."

If the concept succeeds, the method could be extended to diseases such as myasthenia gravis and multiple sclerosis, he said.

Peptimmune specializes in developing therapies based on antigen processing and presentation, which stimulate an immune response. In addition to peptides, the company has advanced two other programs, one of which centers on peptimers, a system for boosting the activity of immune-modulating peptides. Licensed from Harvard University, the approach builds on research that demonstrates large doses of an immunogenic peptide can create antigen-specific tolerance. Under the peptimer umbrella, Peptimmune is investigating follow-on compounds for the pemphigus indication, as well as peptimers with potential for treating multiple sclerosis.

The other program seeks to identify small molecules to inhibit antigen processing as a means of combating autoimmune and inflammatory diseases by halting the processing steps that lead to antigen presentation and immune response. In a project partnered with Peptide Therapeutics Ltd., of Cambridge, U.K., Peptimmune is looking for inhibitors of cathespin-S, an enzyme key to loading the processed peptide antigen.

Peptimmune, which has five employees, will continue operating in its current facilities as an autonomous subsidiary of Genzyme General's Therapeutics business unit, with research to remain under the management of Rasmussen.