Analyzing the clinical efficacy and safety of levocetirizine based on its receptor occupancy, intraclass comparison and role in the treatment of CSU: an AROG consensus statement

Introduction: Chronic spontaneous urticaria (CSU) is characterized by urticaria persisting for more than 6 weeks. Antihistamines, notably sgAH (second generation antihistamines) are the first line of treatment for CSU.

Areas covered: This consensus aimed to review the existing research on receptor occupancy of antihistamines, including levocetirizine, and translate its implications in the treatment of CSU. The consensus deliberations were under the banner of the Antihistamine Receptor Occupancy Group (AROG) from India, an expert panel of 12 dermatologists with a mix of institutional and practitioner backgrounds. This group analyzed the existing translational research on the receptor occupancy of levocetirizine to establish the clinical efficacy and safety of levocetirizine in the treatment of CSU using the grading of recommendations assessment, development, and evaluation (GRADE) method vis-a-vis the varied SGAH.

Expert opinion: SGAH constitute the first step in the therapeutic ladder for managing CSU. Levocetirizine has high bioavailability, high affinity and occupancy of the H1 receptor, rapid onset of action, limited distribution and minimal hepatic metabolism. It exhibits significant anti-inflammatory effects at clinically relevant concentrations. The marked receptor occupancy translates to enhanced efficacy as compared to similarly dosed SGAH with the lower cost making it an appropriate drug for chronic use. Receptor occupancy should be the basis of intra-class head-to-head trials in CSU.