ZymoGenetics Discusses Detailed Results From Successful Phase 3 Trial Evaluating rhThrombin as a Potential Treatment for Surgical Bleeding
Monday September 18, 6:00 am ET
- Analyst and Investor Briefing in New York City Today at 10:00 a.m. Eastern -
SEATTLE, Sept. 18 /PRNewswire-FirstCall/ -- ZymoGenetics, Inc. (Nasdaq: ZGEN - News) today announced detailed results from its pivotal Phase 3 trial of recombinant human Thrombin (rhThrombin) as an aid to controlling bleeding during surgery. The trial compared rhThrombin to bovine thrombin. As announced on September 5th 2006, both the primary and secondary endpoints of the study were met. rhThrombin demonstrated comparable efficacy and a superior immunogenicity profile as compared to bovine thrombin. Both treatments were well tolerated and exhibited similar adverse event profiles in this study.
"ZymoGenetics took a big step toward becoming a commercially successful company with these positive results," said Bruce L.A. Carter, Ph.D., President and Chief Executive Officer of ZymoGenetics. "We believe the thrombin market is underserved and has the potential to expand. We're on track to file a biologics application with the FDA later this year."
Results from the Phase 3 rhThrombin clinical trial were presented on Sunday, September 17 at the Society for Advancement of Blood Management (SABM) meeting by principal investigator Kenneth L. Renkens, Jr., M.D., of the Indiana Spine Group.
The randomized, double-blinded pivotal Phase 3 clinical trial with rhThrombin was conducted at 34 sites in the U.S. and evaluated the product in the same four types of surgery examined in Phase 2 studies: spinal surgery, liver resection, peripheral artery bypass and arteriovenous graft construction. 411 patients were randomized to receive rhThrombin or bovine thrombin; approximately half or 205 patients received rhThrombin. Enrollment was balanced among surgery types as follows and according to study protocol, with 122 patients in spinal surgery, 125 in liver resection, 88 in peripheral artery bypass and 76 in arteriovenous graft construction. The study was designed to support broad product labeling for the use of rhThrombin as an aid to controlling bleeding during surgery.
The primary endpoint of the study was a comparison of the efficacy of rhThrombin versus bovine thrombin, as measured by the overall percentage of patients achieving hemostasis within 10 minutes. The study met its primary endpoint, with rhThrombin achieving hemostasis within 10 minutes 95.4% of the time and bovine thrombin achieving hemostasis within 10 minutes 95.1% of the time. Among the four types of surgery evaluated, the incidence of hemostasis within 10 minutes was similar between treatment groups.
A superior immunogenicity profile was seen with rhThrombin, based on a significantly lower incidence of post-treatment anti-product antibody development. All subjects with both baseline and post-baseline immunogenicity samples were included in the immunogenicity analyses. The incidence of baseline positive anti-product antibody titers was lower for subjects receiving rhThrombin than with bovine thrombin (rhThrombin, n=3/198 or 1.5%; bovine thrombin, n=10/200 or 5%). The incidence of post-treatment anti-product antibody development was significantly lower in the rhThrombin group (rhThrombin, n=3/198 or 1.5%; bovine thrombin, n=43/200 or 22%) (p < 0.0001). Overall, in Phase 1 through 3 studies, rhThrombin showed a rate of antibody development of 1.4%, which was comparable to that seen with placebo (2.4%) in Phase 2 clinical trials.
The incidence and severity of adverse events observed in the Phase 3 study were similar between treatment groups. The most common adverse events occurring in patients treated with rhThrombin and bovine thrombin included incision site complication, nausea, procedural pain, constipation and vomiting. These adverse events are not uncommon in patients undergoing the types of surgeries evaluated in the study. Serious adverse events were experienced by 18% of patients exposed to rhThrombin (n=36); and 22% of those receiving bovine thrombin (n=46). Lab abnormalities were as expected for a surgical population, with a generally similar incidence between groups.
ZymoGenetics will hold an analyst and investor briefing in New York City today at 10:00 a.m. Eastern Time at the Grand Hyatt New York in the Chrysler Boardroom. The meeting agenda will include a review of data by Thomas Reynolds, M.D., Ph.D., Vice President, Medical Affairs and a panel discussion with Dr. Reynolds, Michael J. Dwyer, MBA, Senior Vice President, Sales and Marketing, and William D. Spotnitz, M.D., Director, Surgical Therapeutic Advancement Center, University of Virginia. A live webcast of the meeting will be available at www.zymogenetics.com or callers can listen to the meeting by dialing 800-299-7098 (passcode: 32033209). The international dial in number is 617-801-9715, and the same passcode applies. Participants should log on or dial in to the call approximately 10 minutes prior to the scheduled start time in order to register for the call. The webcast will be archived for 30 days.
About rhThrombin
ZymoGenetics is developing rhThrombin, a recombinant form of human thrombin that is not derived from animal or human blood, as an aid to controlling bleeding during surgery. Thrombin is used in more than 1 million surgeries each year in the United States. Currently, only thrombin derived from bovine blood is available in the U.S. as a stand-alone thrombin product. Bovine-derived thrombin has been associated with the development of antibodies that may cross-react with human blood proteins and in some cases these antibodies appear to be related to serious bleeding complications. The production of recombinant proteins is not dependent on the availability of blood from animals or human donors and can be scaled-up to meet market demand.
About ZymoGenetics
ZymoGenetics creates novel protein drugs with the potential to significantly help patients fight their diseases. The Company is developing a diverse pipeline of potential proprietary product candidates that are moving into and through clinical development. These span a wide array of clinical opportunities that include bleeding, autoimmune diseases and cancer. ZymoGenetics intends to commercialize these product candidates through internal development, collaborations with partners, and out-licensing of patents from its extensive patent portfolio. For further information, visit www.zymogenetics.com . |
