ViroPharma initiates Cinryze Phase 2 subcutaneous trial in patients with HAE

ViroPharma Incorporated (Nasdaq: VPHM) and Halozyme Therapeutics (Nasdaq: HALO) announced today  that ViroPharma has initiated an open-label, multi-dose Phase 2 study to evaluate the safety, and pharmacokinetics and pharmacodynamics of subcutaneous administration of Cinryze® (C1 esterase inhibitor [human)] in combination with Halozyme's Enhanze™ technology, a proprietary drug delivery platform using Halozyme's recombinant human hyaluronidase enzyme (rHuPH20), in subjects with hereditary angioedema (HAE).  Initiation of the clinical trial has triggered a milestone payment of $3 million to Halozyme.

"Routine prophylaxis with intravenous Cinryze has transformed the management of HAE for many patients who also have the option for self administration. The initiation of this first phase 2 study with a novel, subcutaneous combination product represents an exciting new development for patients and their physicians and is an important milestone for ViroPharma," commented Jennifer Schranz, MD, ViroPharma's vice president, clinical research. "Our goal is to optimize the overall convenience of self-administration therapy with a single subcutaneous injection. This is an important part of our efforts to continually enhance the Cinryze experience for both existing and future patients by providing them an alternative administration option."

"The start of this Phase 2 subcutaneous trial in patients with HAE marks a great achievement for our partnership with ViroPharma, and I congratulate the team on this important accomplishment," said Gregory Frost, Ph.D., Halozyme's president and CEO. "Cinryze is the only HAE therapy approved for both routine prophylaxis against attacks along with self administration, and we expect this subcutaneous alternative to provide an important administration option."

Halozyme's proprietary rHuPH20 enzyme facilitates the absorption and dispersion of drugs or fluids that are injected under the skin. When injected under the skin, rHuPH20 transiently generates channels in tissues underlying the outer layers of the skin to increase the absorption and spread of injected drugs.  

This open-label multiple-dose study will be conducted in subjects with hereditary angioedema who previously participated in the ViroPharma Phase 2 trial evaluating subcutaneous Cinryze when given alone.  Qualified subjects will participate in a single 18-day study period, followed by a 30-day post-treatment follow-up.  Subcutaneous administration of Cinryze 1000U and 2000U in combination with rHUPH20 will be assessed.  Additional information about this Phase 2 subcutaneous Cinryze clinical trial can be found at clinicaltrials.gov.

Cinryze is the first and only U.S. FDA-approved C1 esterase inhibitor therapy indicated for routine prophylaxis against angioedema attacks in adolescent and adult patients with hereditary angioedema, a rare, debilitating and potentially fatal disease. Cinryze is currently approved for intravenous administration. Cinryze is also approved by the EMA for the treatment and pre-procedure prevention of angioedema attacks in adults and adolescents with hereditary angioedema (HAE), and routine prevention of angioedema attacks in adults and adolescents with severe and recurrent attacks of hereditary angioedema (HAE), who are intolerant to or insufficiently protected by oral prevention treatments or patients who are inadequately managed with repeated acute treatment.