Allakos Inc. announced it has initiated a Phase 2b clinical trial to evaluate the efficacy, safety and tolerability of subcutaneous lirentelimab in patients with chronic spontaneous urticaria (MAVERICK). Top-line results from the trial are expected in the second half of 2023. The Phase 2b CSU clinical trial follows positive results from an open-label Phase 2a clinical trial with intravenous lirentelimab in patients with chronic urticaria, including cohorts of patients with omalizumab naïve CSU and omalizumab refractory CSU (link).

Patients in the omalizumab naïve cohort had urticaria symptoms despite treatment with antihistamines (up to 4x labeled dose) and had not been previously treated with omalizumab. Omalizumab naïve patients receiving monthly lirentelimab for 6 doses reported a 75% improvement in the 7 day urticaria activity score (UAS7) with 92% of patients achieving a urticaria control test (UCT) score = 12. Patients in the omalizumab refractory cohort had urticaria symptoms despite treatment with antihistamines (up to 4x labeled dose) and treatment with up to 600 mg (2x highest labeled dose) omalizumab for an average duration of 10 months.

Omalizumab refractory patients receiving monthly lirentelimab for 6 doses reported a 61% improvement in UAS7 with 57% of patients achieving a UCT score = 12. The safety results of the trial were generally consistent with previously reported intravenous lirentelimab clinical trials. The most common adverse event was mild to moderate infusion-related reactions (such as flushing, feeling of warmth, headache, nausea, and dizziness) which occurred mostly during the first infusion.

Full results of the trial were published in The Journal of Allergy and Clinical Immunology.