ViroPharma, Halozyme tackle hereditary angioedema treatment

ViroPharma ($VPHM) and Halozyme ($HALO) said they have generated positive early data in a Phase II trial of a drug delivery platform used to treat hereditary angioedema, a life-threatening immune system problem that can cause swelling in the face, airways, abdomen and extremities.

At least 10,000 people in the European Union and 6,500 people in the U.S. suffer from this rare condition, which can incapacitate patients 20 to 100 days annually, the companies note.

Twelve patients with hereditary angioedema took part in the trial, during which they were treated with ViroPharma's drug Cinryze, a C1 esterase inhibitor, combined with Halozyme's Enhanze drug delivery platform. (All were veterans of a related, and promising ViroPharma trial also involving Cinryze.) The Enhanze tech uses Halozyme's recombinant human hyaluronidase enzyme (rHuPH20) combined with other injectable drugs--particularly large molecule biologics--so they can be more easily dispersed and absorbed under the skin. Enhanze enables this by transiently generating tissue channels under the skin's outer layers, the companies said.

While both parties said they plan to present full data at "a future international meeting," they noted that the initial results of the open-label, multiple-dose study demonstrated higher, and potentially more effective amounts of Cinryze in the body rather than injection of the drug alone. This suggests the drug is better absorbed this way, they said, though there were some side effects such as injection site reactions and some pain.

Testing in larger groups of patients will ultimately determine if the drug/delivery system combination is successful. There is plenty to gain if they are because patients with hereditary angioedema are traditionally treated through an IV every few days. The ViroPharma/Halozyme concept could allow for a similar treatment, but with a single injection under the skin, vastly improving patients' quality of life.

While the number of patients may seem small, other companies such as Genzyme have long demonstrated the ability to be very successful both clinically and financially, developing treatments for rare conditions involving relatively minute numbers of people.

- here's the release
- read the story at