CDC Selects New Sites for Pilot Study of Inhibitors in Hemophilia

The Division of Blood Disorders (DBD) at the Centers for Disease Control and Prevention (CDC) is adding four new centers to a multi-state collaborative study to help identify factors that might put people with hemophilia at risk for developing an inhibitor, an antibody that prevents drugs that treat hemophilia from working effectively.  The study is made possible by a $3 million grant from Wyeth Pharmaceuticals to the CDC Foundation. 

Hemophilia is an inherited bleeding disorder that affects 18,000 persons (primarily males) in the United States. The disorder results from deficiencies in blood clotting factors and can lead to spontaneous internal bleeding and bleeding following injuries or surgery. These bleeding episodes can cause severe joint damage, neurological damage, damage to other organ systems involved in the hemorrhage, and, in rare cases, death. About three-quarters of people with hemophilia in the United States receive care in federally funded specialized treatment centers.

As many as one-third of individuals with hemophilia will develop an inhibitor during their life time.  Although most of these inhibitors will resolve on their own, about 5 percent to 7 percent of people with hemophilia have a long-term inhibitor that makes treatment of bleeds very difficult and expensive. 

The treatment centers will work with patients to collect data – such as race and ethnicity, age when they first had a bleed and the type of drug used for treatment of bleeds – that researchers suspect may play a role in the development of inhibitors.  The DBD laboratory is not only performing the blood test required to diagnose an inhibitor but also conducting genetic studies to see what role a person’s genes may play in the development of inhibitors. The four new pilot sites will continue to investigate these risk factors in addition to collecting information on children under 2 years of age.

 “We are excited about this opportunity to collect data on young children because the risk for developing an inhibitor is highest during the early years of life when treatment of bleeds begins.  This information will help scientists learn more about the causes of this life-threatening complication of hemophilia,” said J. Michael Soucie, associate director for science in CDC’s Division of Blood Disorders.

Approximately 200 young children will be added to the pilot study through the new sites, bringing the total number of participants in this preliminary phase of the study to 700.  The treatment centers are currently recruiting new participants for the study.  The centers include:

  • Vanderbilt University Medical Center, Nashville, TN
  • Emory University Hemophilia Program Office, Atlanta, GA
  • The Children's Mercy Hospital, Kansas City, MO
  • University of Massachusetts Medical School - Worcester, Worcester, MA
  • Comprehensive Bleeding Disorders Center, Peoria, IL
  • University of Iowa Hospitals and Clinics, Iowa City, IA
  • University of Michigan Hemophilia and Coagulation Disorders Program, Ann Arbor, MI
  • Virginia Commonwealth University, Richmond, VA
  • Indiana Hemophilia and Thrombosis Center, Indianapolis, IN
  • Mountain States Regional Hemophilia and Thrombosis Center, Aurora, CO
  • Children's Hospital and Regional Medical Center, Seattle, WA
  • Phoenix Children's Hospital, Phoenix, AZ
  • Children's Healthcare of Atlanta at Scottish Rite, Atlanta, GA

When the pilot phase of the study is complete and funding becomes available, more sites will be added. This project demonstrates how cooperation between federal agencies, the treatment centers and industry can lead to important research for this population. Researchers hope that results from the study will eventually lead to a lower rate of inhibitor development, decreased costs to the nation’s public health system and new safe and effective treatment options for people with hemophilia.

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