Biologics for the Use in Chronic Spontaneous Urticaria: When and Which

Guidelines for the treatment of chronic spontaneous urticaria
(CSU) recommend the use of the IgE-targeted biologic
omalizumab in patients with antihistamine-refractory disease.
The rationale for this is supported by the key role of IgE and its
high-affinity receptor, FcεRI, in the degranulation of skin mast
cells that drives the development of the signs and symptoms of
CSU, itchy wheals, and angioedema. Here, we review the current
understanding of the pathogenesis of CSU and its autoimmune
endotypes. We describe the mechanisms of action of
omalizumab, the only biologic currently approved for CSU, its
efficacy and ways to improve it, biomarkers for treatment
response, and strategies for its discontinuation. We provide
information on the effects of the off-label use, in CSU, of
biologics licensed for the treatment of other diseases, including