Paris, October 20, 2020, 9.15pm
AB Science announces positive top-line Phase 3 results
for oral masitinib in severe asthma
This is the second Phase 3 study to demonstrate efficacy for masitinib in severe asthma
AB Science SA (Euronext – FR0010557264 – AB) today announced that the Phase 3 study (AB14001) evaluating oral masitinib in severe asthma uncontrolled by high-dose inhaled corticosteroids (ICS) and with eosinophil level >150 cells/μL met its primary endpoint.
The pre-specified primary analysis was rate of severe asthma exacerbations, with masitinib demonstrating a statistically significant 29% reduction in severe exacerbations relative to placebo (p=0.022). The frequency of severe asthma exacerbations was 0.43 in the masitinib arm, versus 0.62 in the placebo arm. Duration of exposure was well-balanced between the treatment-arms (16 months in the masitinib arm and 17 months in the placebo arm). Sensitivity analysis based on the rate of moderate and severe asthma exacerbations was consistent with the primary analysis and detected a statistically significant 31% reduction in exacerbations (p=0.005) between masitinib and placebo. The frequency of moderate and severe asthma exacerbations was 0.55 in the masitinib arm, versus 0.80 in the placebo arm.
This is the second time that masitinib has demonstrated efficacy in reducing severe asthma exacerbations in patients with severe asthma. The treatment effect observed in study AB14001 is comparable with the effect previously reported for study AB07015. In that first phase 3 study, which evaluated masitinib in severe asthma uncontrolled by oral corticosteroids (OCS), masitinib significantly (p=0.010) reduced the rate of severe asthma exacerbations by 35% as compared with placebo. The frequency of severe asthma exacerbations in study AB07015 was 0.34 in the masitinib arm, versus 0.45 in the placebo arm. Duration of exposure was also well-balanced between the treatment arms (13 months in both treatment arms).
Safety was consistent with the known tolerability profile for masitinib.
Detailed results will be presented at an upcoming medical meeting.
The study AB14001 enrolled patients with blood eosinophil level >150 cells/μL, which differs from the population usually addressed by biological treatments, targeting patients with high eosinophils (>300 cells/μL or above) defined as Th2-high eosinophilic asthma.
Masitinib is a first in class drug in severe asthma, distinct from biological treatments targeting type-2 high eosinophilic phenotypes of asthma. Masitinib has a dual mechanism of action, targeting mast cells and PDGFR signaling that are both involved in airway remodeling associated with severe asthma. It has also been shown that increased mast cell activity is associated with both eosinophilic (Th2-high) and non-eosinophilic (Th2-low) asthma phenotypes. Furthermore, masitinib is orally administered, whereas biologics are sub-cutaneous, which is an advantage because oral administration is less of a burden for patients and facilitates compliance for long-term use.
There is still a need for effective therapy of patients with severe asthma. Biologics are established in first line treatment in severe asthma patients with blood eosinophil levels of ≥300 cells/µL. However, these therapies have limited efficacy in reducing severe asthma exacerbations for severe asthmatics with blood eosinophil levels of <300 cells/µL. In