Antihistamines have historically been used to treat chronic spontaneous urticaria (CSU). Studies utilizing various formulations and dosage regimes have outlined the limitations of their effectiveness over time, underlining the need for alternative treatment methods. Data continue to mount showing the monoclonal anti-immunoglobulin E antibody omalizumab, which was formerly designated for the treatment of severe atopic asthma, may have a positive therapeutic and safety profile for CSU patients who are resistant to the action of antihistamines. A slew of studies has been published since the beginning of 2013, paving the road for the approval of omalizumab for the treatment of CSU. Dose-finding studies have suggested that 300 mg once a month is a feasible optimum treatment plan. RCTs demonstrating efficacy were supplemented by open-label studies verifying their efficacy in real-world settings. So far, one study has presented promising results for the use of rituximab, a biologic drug that depletes B cells in the bloodstream, in patients with CSU.
Over the last year, more persuasive data supporting the effectiveness and safety of omalizumab in the treatment of CSU has emerged, giving another option for dealing with antihistamine-resistant instances.