A clinical trial evaluating an experimental treatment for patients infected with West Nile virus (WNV) has begun enrolling volunteers at 36 sites nationwide, the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health, announced today. This study is part of a larger effort by NIAID to develop new ways to prevent and treat the disease.
"West Nile virus has emerged as a problem in the United States again this year, and public health officials are particularly concerned because the disease appears to be spreading more quickly and more widely than last year," comments Anthony S. Fauci, MD, NIAID director. "NIAID is excited to be supporting this clinical trial for a specific therapeutic intervention against WNV.
"Currently, clinicians can provide only supportive care for patients infected with WNV," notes Fauci. "We hope that the results from this study will ultimately give physicians and their patients a useful treatment option."
The new study will assess whether WNV-infected individuals given antibodies to the virus - one of the immune system's arsenal of disease-fighting weapons - are better able to fend off the severe symptoms of WNV, such as encephalitis, that contribute to the deaths of many individuals who become infected.
Omrix, an Israeli company partnering with NIAID on this study, has an immunoglobulin product that contains antibodies to WNV. Omrix developed this immunoglobulin treatment from the plasma of Israeli donors who have high levels of antibodies to WNV. WNV has been endemic in Israel for decades, and many Israelis who give blood have antibodies to WNV. By giving patients the immunoglobulin product (called Omr-IgG-am) containing the WNV antibodies, researchers hope to help fight the virus in the brain of infected individuals who have developed WNV encephalitis - an inflammation of the brain - or who are at risk for developing this complication.
"This study will provide important information on the safety of intravenous immunoglobulin G-containing antibodies to WNV for treatment of encephalitis," says study chair Richard Whitley, MD, of the University of Alabama at Birmingham. In addition to determining if Omr-IgG-am is safe and well-tolerated, the study will collect information on the efficacy of this treatment in preventing death or neurologic disability. The study also will help researchers characterize the natural history of severe WNV infection.
The study seeks to enroll 100 hospitalized patients 18 years of age or older who have WNV-related encephalitis or are determined to be at risk of developing encephalitis based on clinical symptoms and the presence of antibodies to the virus. Patients will be assigned at random to one of three groups: those given standard intravenous immunoglobulin from U.S. sources (which has no detectable antibodies to WNV); those given Omr-IgG-am; or those given a placebo. Each participant will receive a single-dose infusion of drug or placebo and will be observed for the first week and then at days 7 and 14, and at 1 and 3 months.
Volunteers are being recruited through NIAID's Collaborative Antiviral Study Group (CASG), based at 35 sites around the country (for more information, see the CASG Web site at www.casg.uab.edu) and through the NIH Clinical Center in Bethesda, Md. More information on the trial and participating sites also can be found at www.clinicaltrials.gov. NIAID's Walla Dempsey, Ph.D., is project officer on the contract that funds the study.
Information about NIAID's research on WNV can be found at http://www.niaid.nih.gov/publications/wnile/default.htm.
NIAID is a component of the National Institutes of Health (NIH), which is an agency of the Department of Health and Human Services. NIAID supports basic and applied research to prevent, diagnose and treat infectious and immune-mediated illnesses, including HIV/AIDS and other sexually transmitted diseases, illness from potential agents of bioterrorism, tuberculosis, malaria, autoimmune disorders, asthma and allergies.
Source: National Institutes of Health