LongBio Pharma (Suzhou) Co., Ltd. reported that its lead candidate LP-003 met all pre-specified primary endpoints in a China-based Phase III clinical trial targeting moderate-to-severe seasonal allergic rhinitis (AR) inadequately controlled by standard of care (SoC) therapy.

The multi-centre, randomised, double-blind, placebo-controlled study enrolled 546 patients who were assigned to receive either a 100 mg LP-003 injection or placebo once every four weeks during the peak pollen season. Efficacy was measured by the change in total nasal symptom scores (TNSS) during the peak pollen period. According to the company, LP-003 delivered “highly statistically and clinically significant” improvements over placebo on this primary endpoint.

Key secondary evaluations—daily nasal symptom and rescue medication scores (DNSMS), daily ocular symptom and rescue medication scores (DNOMS), pharmacokinetics (PK) and pharmacodynamics (PD)—also formed part of the trial design. Detailed data were not disclosed in the announcement, but management stated that efficacy and safety outcomes supported the primary findings.

LP-003 is a novel anti-IgE monoclonal antibody designed to bind free IgE and prevent its interaction with the high-affinity FcεRI receptor, thereby disrupting IgE-mediated Type I hypersensitivity reactions. Beyond seasonal AR, the candidate is in development for chronic spontaneous urticaria (CSU), allergic asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and food allergy, with investigational new drug (IND) approvals and clinical trials underway in China.

LongBio Pharma, established in 2020 and headquartered in Shanghai and Changshu, focuses on in-house discovery and development of biologics for allergic and autoimmune diseases across rhinology, dermatology, respiratory, hematology and nephrology indications. The company emphasised that successful completion of the Phase III trial does not guarantee eventual regulatory approval or commercialisation of LP-003.