This study will evaluate the safety and usefulness of omalizumab (anti-IgE, Xolair) in
reducing eosinophil counts and improving symptoms in patients with eosinophilic
gastroenteritis (EG). EG is a disorder of unknown cause in which eosinophils, a type of white
blood cell, are increased in the blood and gut tissue. Patients with EG have symptoms like
stomach pain, bloating, and vomiting. About 50 percent of EG patients have food or
environmental allergies, which may play a role in EG. Some patients with EG improve
significantly on diets avoiding foods to which they are allergic. Immunoglobulin E (IgE) is
an antibody that plays an important role in initiating allergic reactions. Omalizumab is a
monoclonal antibody directed against IgE. The Food and Drug Administration approved
omalizumab in 2003 for treating patients 12 years of age and older with allergic asthma.
Patients between 12 and 76 years of age with eosinophilic gastroenteritis who have a blood
eosinophil count of 500 or more and who have a food allergy or allergy to an inhaled allergen
may be eligible for this study. Candidates are screened with a medical history, physical
examination, and blood and urine tests.
Participants undergo the following procedures:
- Leukapheresis. This procedure is done to collect quantities of white blood cells to
study the effects of omalizumab on eosinophils and other immune substances. Blood flows
from a needle placed in an arm vein through a catheter (plastic tube) into a machine
that separates the blood into its components by centrifugation (spinning). Some of the
white cells are removed and the rest of the blood (red cells, plasma and platelets) is
returned to the body through a needle in the other arm.
- Skin testing. Participants are tested for allergies to specific substances. A small
amount of various allergens (substances that cause allergies) are placed on the
subject's arm. The skin is pricked at the sites of the allergens and the skin reaction
after several minutes is observed.
- Upper and lower endoscopy. One or both of these procedures is done, depending on the
part of the gastrointestinal tract that is involved, to examine the tract. If both
procedures are done, they are performed at the same time. For the upper endoscopy, the
subject's throat is sprayed with a numbing medicine and a long, flexible tube is passed
through the esophagus, stomach and small intestine. For the lower endoscopy, the tube is
passed through the rectum into t...
Phase:
Phase 2
Details
Lead Sponsor:
National Institute of Allergy and Infectious Diseases (NIAID)