The National Hemophilia Foundation’s (NHF’s) Medical and Scientific Advisory Council (MASAC) recently issued a new recommendation concerning inhibitor testing and surveillance for patients with hemophilia A and B. MASAC Document #236, adopted by NHF’s Board of Directors on October 6, 2015, was created in response to significant findings from the US Centers for Disease Control and Prevention’s (CDC's) Hemophilia Inhibitor Research Study (HIRS).
A six-year-long research initiative, HIRS was designed to assess the feasibility and utility of conducting national monitoring for inhibitors among people with hemophilia living in the US. A total of 1,163 patients with hemophilia from 17 US-based hemophilia treatment centers (HTCs) were enrolled and subsequently monitored for up to 6 years to establish the optimal way to determine who was at risk for developing an inhibitor.
In light of the results, investigators concluded the following:
- All people with hemophilia, regardless of age, are at risk for developing inhibitors
- One-third of newly-developed inhibitors were found in people with non-severe hemophilia
- One-half were older than 5
- One-quarter had used infused factor for more than 150 days
- Six out of 10 people with hemophilia with an inhibitor had no symptoms
- Regular screening of people with hemophilia for early detection of an inhibitor by the CDC laboratory is feasible, and will inform efforts to measure rates of this complication
The results prompted CDC to enhance its surveillance system to include inhibitor testing, to address cost-related barriers to the screening process and establish a standardized testing approach to be employed by all participating HTCs.
In response to CDC’s findings, MASAC created a document that includes a series of specific recommendations relevant to lab testing, standardization of an inhibitor screening method, surveillance, inhibitor prevention, research and consumer/provider education.
View the complete list of current MASAC documents. To request a hard copy of any current documents, please contact HANDI, NHF’s information resource center: handi@hemophilia.org (link sends e-mail) or 1.800.424.2634.
