Top-line results from HyQ subcutaneous IG phase III study in patients with primary immunodeficiency

Baxter International Inc. and Halozyme Therapeutics, Inc. today announced top-line results of a phase III study of HyQ, an investigational facilitated subcutaneous immune globulin (IG) product for use in patients with primary immunodeficiency (PI). The subcutaneous administration is facilitated by recombinant human hyaluronidase, an enzyme that increases dispersion and absorption of the IG. The data confirm the interim results presented late in 2010 and support the recent submission of a biologics license application to the United States Food and Drug Administration.

"As a long-standing leader in the IG market, Baxter is committed to continually developing and delivering therapies that make a meaningful difference in the lives of patients," said Ludwig Hantson, President of Baxter's BioScience business. "Completion of this important trial brings us closer to providing an option that can address the needs of patients with immune deficiency disorders."

The phase III prospective, open-label, study enrolled 89 patients with PI in 15 centers in the United States and Canada, and evaluated the effectiveness of HyQ in the prevention of infections and measured other secondary endpoints including tolerability.

The objective of the study was to infuse a 3 week or 4 week dose of 10% HyQ in a single infusion site. In the study, the acute serious bacterial infection rate was 0.025 per patient per year, which is below the required efficacy threshold of 1.0. In the tolerability assessment of HyQ, the most frequently reported adverse reactions were infusion site reactions (20% of infusions), headache (3% of infusions), fatigue (1% of infusions) and pyrexia (fever) (1% of infusions).

"Patients with primary immune deficiencies have a chronic, life-long condition that requires diligent, ongoing treatment," said Richard L. Wasserman, MD, PhD, Clinical Professor of Pediatrics at University of Texas Southwestern Medical School, and an investigator in the HyQ phase III trial. "Physicians who are treating these patients will welcome this new option."

The completion of the phase III trial established a foundation for the HyQ extension study that will further evaluate HyQ administration to patients through March 2012. In addition to the recent regulatory submission in the United States, Baxter expects to file in Europe and Canada in the coming months, and will present results from the phase III study by the end of 2011.

"Submission of this BLA for HyQ represents a significant achievement for Halozyme and Baxter," said Gregory I. Frost, Ph.D., Halozyme's President and CEO. "Most importantly, these efforts represent the commitment of our scientists and clinicians to developing new treatment options for patients with primary immunodeficiency."