Omalizumab in Chronic Spontaneous Urticaria: Assessment of Response in Twenty-Five Patients.
Omalizumab is a recombinant humanized monoclonal antibody against immunoglobulin E.
It is approved for the treatment of chronic spontaneous urticaria in patients
≥12-years of age.
Mechanism of action of omalizumab is by decreasing serum levels of free
IgE and also by down-regulation of the high-affinity IgE receptors on mast cells,
basophils, and dendritic cells.
The most effective dose of omalizumab is 150-300 mg subcutaneous
injection every four weeks.
Urticaria is a common inflammatory condition characterized by
wheals that last less than 24-hours. When urticaria continues for more
than 6-weeks with no apparent cause, it is called CSU.
The first line treatment of CSU is 2nd generation anti H1-antihistamine therapy.
However, in a significant proportion of patients, symptoms persist despite using
the second line treatment full dose of 2nd generation H1-antihistamines.
Current global guidelines for the treatment of CSU recommend other add-on
therapies as a second or third-line treatment that includes adding omalizumab
to the 2nd generation anti H1-antihistamines.
If recurrence occurred, reintroduction of omalizumab treatment is required.
In our study, the 7 patients whom did not require a 2nd course of omalizumab treatment
were those whom developed mild symptoms only in the first 2-months of omalizumab treatment.
Patients whom had moderate-severe flares-up in the last 2-months of the 1st course received the 2nd course immediately without stopping omalizumab.
Those whom had mild flares-up in the last 2-months of the 1st course, the omalizumab
was stopped and then reintroduced because they got moderate-severe flares-up.
This indicates that it is better not to stop omalizumab if the patient
has mild flares-up in the last 2-months of omalizumab therapy.
Dermatol Open J. 2022; 7(1): 1-5. doi: 10.17140/DRMTOJ-7-147