ACARIZAX Meets Primary Objective in Phase 3 Bridging Trial in Chinese Participants with House Dust Mite Allergic Rhinitis – ALK
ALK announced positive topline results from the phase 3 bridging trial evaluating the efficacy and safety of its house dust mite (‘HDM’) sublingual immunotherapy (‘SLIT’) tablet, Acarizax, in Chinese participants aged 12 – 65 years with HDM allergic rhinitis/rhinoconjunctivitis, with or without asthma. The trial was designed to show a consistent trend with the previous clinical trials conducted with Acarizax outside China.
Participants were treated for 24-28 weeks with either Acarizax or placebo. 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.
The trial achieved its primary objective. 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, thereby substantially exceeding the predefined success criterion that was agreed with the Chinese authorities. 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.
“The results of our phase 3 clinical trial in China are robust and highly consistent with more than a decade of data on our house dust mite tablet, confirming that it is both efficacious and safe for Chinese patients and can make a real difference for allergy sufferers in China. Together with our partner GenSci, we will now continue the dialogue with the Chinese health authorities to seek regulatory approval, so that we can make this treatment available to the millions of people in China living with house dust mite allergy.” – Jacob Glenting, EVP and Head of Global R&D.
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 trial was designed to generate Chinese clinical data which, together with existing global data, is expected to support local regulatory approval of Acarizax.
Subject to approval by the Chinese authorities, Acarizax will be added to GenSci’s portfolio under the partnership agreement announced in September 2025 (company release No 15/2025).
Worldwide, China is the country with the highest number of people suffering from house dust mite allergy. Yet the market remains significantly underpenetrated with estimated more than 100 million affected and less than 1 million people currently receiving allergy immunotherapy treatment.
The trial results do not affect ALK’s financial guidance for 2026.
