Harbour BioMed, Windward Bio Post Phase 2 Data for Twice-Yearly Asthma Antibody
Cambridge, Massachusetts – September 11, 2026 -- Harbour BioMed (HKEX: 02142) and partner Windward Bio reported positive Phase 2 interim results for HBM9378/WIN378, a twice-yearly TSLP-blocking antibody, from the 147-patient POLARIS-1 asthma trial, clearing the path for two Phase 3 studies.
Interim data show up to 174 mL lung-function gain after single dose
The Phase 2 interim analysis, conducted on the first 98 of 147 enrolled patients with uncontrolled moderate-to-severe asthma, found FEV1 increases of up to 174 mL, with a placebo-adjusted mean increase of 256 mL (p=0.033) at Week 24 after a single dose.
Biomarkers for airway inflammation drop sharply
FeNO fell by up to 24 ppb, a 43% reduction (p=0.006), while blood eosinophil counts dropped by up to 200 cells/μL, a 51% decline (p0.0001). Near-maximal effects appeared as early as Week 2 and were sustained through Week 24.