TY - JOUR
T1 - Omalizumab rapidly decreases nasal allergic response and FcεRI on basophils
AU - Lin, Henry
AU - Boesel, Kevin M.
AU - Griffith, Daniel T.
AU - Prussin, Calman
AU - Foster, Barbara
AU - Romero, F. A.
AU - Townley, Robert
AU - Casale, Thomas B.
N1 - Funding Information:
Supported by a grant from Genentech, Inc, South San Francisco, California. Basophil flow cytometric analysis was supported by the NIAID Division of Intramural Research, Bethesda, Md.
PY - 2004/2
Y1 - 2004/2
N2 - Background: Omalizumab is a monoclonal anti-IgE antibody that is effective for the treatment of allergic respiratory disorders; however, its onset of action is unknown. Objective: This study was designed to determine the onset of action of omalizumab through the use of a challenge model to determine time-dependent inhibition of ragweed-induced changes in nasal volume as well as correlate the kinetics of omalizumab-induced decreases in serum free IgE and FcεRI receptors on basophils. Methods: We conducted a 6-week, randomized, double-blind, placebo-controlled study of 24 rhinitic patients with ragweed allergy. After PD30 ragweed nasal allergen challenge, patients received either omalizumab, ∼0.016 mg/kg per IgE (IU/mL), or placebo at days 0 and 28 and were rechallenged with ragweed PD30 dose biweekly. FcεRI expression on blood basophils was determined by flow cytometry at baseline and 7, 14, 28, and 42 days after treatment. IgE levels were measured at baseline and on days 3, 28, and 42. Results: Mean IgE levels decreased by 96% (P <.001) from baseline within 3 days In the omalizumab group. Baseline 30% ragweed-induced nasal volume response was decreased to 20.4% at 7 to 14 days (P <.001) and 12.2% at 35 to 42 days (P <.001) for the omalizumab group. There was a median decrease in basophil FcεRI expression of 73% (P <.001) In the omalizumab group, with maximum inhibition occurring within 14 days of treatment. No significant changes in IgE levels, nasal allergen challenge responses, or basophil FcεRI expression were observed throughout the study in the placebo group. Conclusions: Our study showed that the onset of action by omalizumab in blunting ragweed-induced nasal responses is within 2 weeks, and this response was associated with 2 putative mechanisms of action: decreased serum free IgE and decreased FcεRI receptor expression on immune effector cells.
AB - Background: Omalizumab is a monoclonal anti-IgE antibody that is effective for the treatment of allergic respiratory disorders; however, its onset of action is unknown. Objective: This study was designed to determine the onset of action of omalizumab through the use of a challenge model to determine time-dependent inhibition of ragweed-induced changes in nasal volume as well as correlate the kinetics of omalizumab-induced decreases in serum free IgE and FcεRI receptors on basophils. Methods: We conducted a 6-week, randomized, double-blind, placebo-controlled study of 24 rhinitic patients with ragweed allergy. After PD30 ragweed nasal allergen challenge, patients received either omalizumab, ∼0.016 mg/kg per IgE (IU/mL), or placebo at days 0 and 28 and were rechallenged with ragweed PD30 dose biweekly. FcεRI expression on blood basophils was determined by flow cytometry at baseline and 7, 14, 28, and 42 days after treatment. IgE levels were measured at baseline and on days 3, 28, and 42. Results: Mean IgE levels decreased by 96% (P <.001) from baseline within 3 days In the omalizumab group. Baseline 30% ragweed-induced nasal volume response was decreased to 20.4% at 7 to 14 days (P <.001) and 12.2% at 35 to 42 days (P <.001) for the omalizumab group. There was a median decrease in basophil FcεRI expression of 73% (P <.001) In the omalizumab group, with maximum inhibition occurring within 14 days of treatment. No significant changes in IgE levels, nasal allergen challenge responses, or basophil FcεRI expression were observed throughout the study in the placebo group. Conclusions: Our study showed that the onset of action by omalizumab in blunting ragweed-induced nasal responses is within 2 weeks, and this response was associated with 2 putative mechanisms of action: decreased serum free IgE and decreased FcεRI receptor expression on immune effector cells.
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U2 - 10.1016/j.jaci.2003.11.044
DO - 10.1016/j.jaci.2003.11.044
M3 - Article
C2 - 14767445
AN - SCOPUS:1142309487
VL - 113
SP - 297
EP - 302
JO - Journal of Allergy and Clinical Immunology
JF - Journal of Allergy and Clinical Immunology
SN - 0091-6749
IS - 2
ER -