Phase 3 trial in China successfully confirms ACARIZAX® safety and efficacy in patients with house dust mite allergy

Positive topline results from the phase 3 bridging trial were recently released, which was designed to evaluate the efficacy and safety of ACARIZAX® in Chinese participants aged 12-65 years with HDM allergic rhinitis/rhinoconjunctivitis, with or without asthma.

ACARIZAX® is a house dust mite (‘HDM’) sublingual immunotherapy (‘SLIT’) tablet developed by Abelló A/S ("ALK"). Under the agreement announced in September 2025, GenSci will now work with our partner ALK to file for regulatory approval of ACARIZAX® in China. Filing is expected in the first half of 2027.

The trial was a randomised, double-blind, placebo-controlled, multi-site phase 3 registration trial conducted in China, enrolling 327 participants who received a once-daily treatment with ACARIZAX® or placebo for 24-28 weeks. The primary endpoint was the average daily total combined rhinitis score (‘TCRS’) during the primary efficacy assessment period. The TCRS was measured by recording the allergy symptoms and pharmacotherapy use in the last 4 weeks of treatment.

Primary objective was achieved in this trial, with efficacy consistent with previous trials. The absolute treatment difference of the TCRS was 1.11 (with a lower bound of the 95% confidence interval exceeding zero; the relative difference was 19.1%) favouring ACARIZAX® over placebo. The trial also demonstrated the treatment to be safe and well-tolerated in both the adolescent and adult age groups in line with the safety profile established with previous trial results.

The trial performed well across endpoints as well as key measures of trial conduct, including participant retention and treatment compliance:

• A favourable treatment difference was observed in the overall population, and in both adult and adolescent subgroups

• Early onset of efficacy was demonstrated from week 8, during the first TCRS efficacy assessment period

• When asked to compare their rhinitis symptoms before and after treatment, participants treated with ACARIZAX® were 4.3 times more likely to feel better at the end of the trial than those who received placebo

• The trial was executed successfully, with high treatment compliance and low participant dropout rates

Worldwide, China is the country with the highest number of people suffering from house dust mite allergy, with estimated more than 100 million affected while less than 1 million people currently receiving allergy immunotherapy treatment. Together with our partner ALK, GenSci will remain committed to drive innovation and advance clinical development, so as to make a difference to millions of people in China living with house dust mite allergy.