Ligelizumab

China-based LongBio Pharma (Suzhou) Co., Ltd announced positive topline results from a Phase II trial of LP-003, its next-generation anti-IgE antibody, in patients with chronic spontaneous urticaria (CSU) who remained symptomatic despite H1 antihistamine treatment. The data, presented as a late-breaking poster at the 2026 AAAAI Annual Meeting, showed LP-003 achieved statistically superior outcomes compared with omalizumab (Xolair) across two key efficacy endpoints — a result that, if confirmed in Phase III, could position the molecule as the first new anti-IgE therapy to reach the market in more than two decades. The trial (NCT06228560, CTR20233300) was a multicenter, randomized, double-blind, placebo- and active-controlled study conducted in China. A total of 202 adults with CSU were enrolled and assigned to one of five arms: LP-003 at 100 mg every four weeks (Q4W), LP-003 200 mg Q4W, LP-003 200 mg every eight weeks (Q8W), omalizumab 300 mg Q4W, or placebo. The treatment duration was 24 weeks. The primary endpoint was the proportion of patients achieving a weekly Urticaria Activity Score of zero (UAS7=0) — denoting complete absence of hives and itch — at Week 12, with the top rate of 66.7% achieved in the LP-003 200 mg Q8W arm, and 57.5% in the LP-003 200 mg Q4W arm, versus 43.6% in the omalizumab arm, and 10.8% in the placebo arm. The comparison between LP-003 200 mg Q8W and omalizumab reached statistical significance (p=0.0405). A second key efficacy measure, the least-squares mean change from baseline in UAS7 at Week 12, was −26.63 for LP-003 200 mg Q8W versus −21.85 for omalizumab (p=0.0137). By Week 4, complete remission rates across LP-003 groups ranged from 35% to 35.9%, suggesting a fast onset of action relative to the comparator. LongBio described the safety profile as favorable, though no quantitative adverse-event data were disclosed in the topline release. The company said a Phase III trial for CSU in China is expected to begin in H1 2026. Separately, LP-003’s lead indication is seasonal allergic rhinitis (SAR), for which a Phase III trial in China has completed enrollment and a Biologics License Application (BLA) submission to China’s National Medical Products Administration (NMPA) is planned in or before Q3 2026. If approved, LP-003 would become the first and only innovative anti-IgE drug to be launched globally in over 20 years since the approval of omalizumab. LP-003 is a monoclonal antibody that neutralizes free immunoglobulin E (IgE), the same target as omalizumab. By binding circulating IgE, the antibody prevents it from engaging the high-affinity IgE receptor FcεRI on mast cells and basophils, reducing degranulation and the downstream release of histamine and other mediators that drive wheals and pruritus. Over time, anti-IgE therapy also downregulates FcεRI surface expression, further dampening the allergic cascade. LongBio states that LP-003 has 860-fold greater IgE binding affinity and 30-fold higher blocking activity than omalizumab, along with a longer half-life. The CSU treatment landscape has evolved in the past two years. Key competing assets include: Novartis’s remibrutinib (LOU064), an oral Bruton’s tyrosine kinase (BTK) inhibitor that has completed Phase III trials in CSU and received a positive CHMP opinion for EU approval. Remibrutinib acts downstream of IgE signaling, inhibiting mast cell and basophil activation directly, and represents a mechanistically distinct oral alternative. Sanofi/Regeneron’s dupilumab (Dupixent), an IL-4 receptor alpha antibody already approved for multiple type 2 inflammatory conditions, which has received a positive CHMP recommendation for CSU in children aged 2–11 years and is being studied in broader CSU populations. United BioPharma’s UB-221, another anti-IgE monoclonal antibody in Phase II for CSU, which targets IgE with a reported CD23-mediated IgE downregulation mechanism. Novartis’s ligelizumab (QGE031), a high-affinity anti-IgE antibody that completed Phase III in CSU but whose development extension was terminated, leaving its forward trajectory in this indication unclear.