Interim readout of 22 patients shows unprecedented efficacy data compared to prior atopic dermatitis (AD) studies with biologics: 60.0% of dupilumab-experienced AD patients treated with 400mg eblasakimab weekly achieved EASI-90 (at least a 90% reduction in their Eczema Area Severity Index (EASI) score) and 66.7% achieved a vIGA score of 0 or 1 (clear or almost clear skin) after 16 weeks, versus 14.3% of patients on placebo.
20% of patients treated with eblasakimab achieved EASI-100 (100% reduction in their EASI score) versus 0% on placebo.
Of the six patients treated with eblasakimab that previously had an inadequate response to dupilumab, 66.7% achieved EASI-90 and a vIGA score of 0 or 1 after 16 weeks.
Eblasakimab produced rapid and clinically meaningful itch relief versus placebo. The mean reduction in peak pruritus numerical rating scale (PP-NRS) score for eblasakimab-treated patients was 58.9% compared to a 12.9% reduction for placebo.
Data from this unique study of dupilumab-experienced AD patients shows eblasakimab has the potential to be highly effective in AD patients even if dupilumab has not been.
SAN MATEO, Calif. and SINGAPORE, April 22, 2024 (GLOBE NEWSWIRE) -- ASLAN Pharmaceuticals (Nasdaq: ASLN), a clinical-stage, immunology-focused biopharmaceutical company developing innovative treatments to transform the lives of patients, today announced positive interim results from the Phase 2 study of eblasakimab in moderate-to-severe atopic dermatitis (AD) adult patients previously treated with dupilumab, TREK-DX. The primary endpoint, which is the percent change in Eczema Area Severity Index (EASI) score from baseline to week 16, was statistically significant when compared to placebo (p=0.0059), even though the interim analysis was not powered for statistical significance due to the sample size. 73.3% (11/15) of eblasakimab-treated patients achieved a reduction in EASI score of at least 75% from baseline (EASI-75) compared to 14.3% (1/7) on placebo (p=0.0431).
"We are extremely pleased to see eblasakimab delivering these spectacular results using a dosing regimen higher than we have tested previously. Most patients on eblasakimab achieved EASI-90 and vIGA of 0 or 1 after just 16 weeks of treatment, with numbers unprecedented in other biologics AD studies. Notably, in patients that previously had an inadequate response to dupilumab, two-thirds achieved EASI-90 and vIGA 0 or 1 when treated with eblasakimab," said Dr Carl Firth, Chief Executive Officer of ASLAN Pharmaceuticals.
"We know that over 60% of dupilumab-treated patients fail to achieve an IGA score of 0 or 1 after 16 weeks1, and, of those patients that do achieve it, still half do not maintain it after the subsequent 36 weeks2. The data we have announced today provide compelling evidence that eblasakimab, with its unique mechanism of action, has the potential to be an important new therapy for this emerging patient population. We look forward to announcing the topline readout from the full dataset of the TREK-DX study at the end of this year, the first and only placebo-controlled study of dupilumab-experienced AD patients, and to optimizing the dose regimen for patients in the planned Phase 3 studies of eblasakimab."
Summary of the interim data
The TREK-DX trial is enrolling moderate-to-severe adult AD patients who have discontinued dupilumab treatment for any reason, including inadequate control of AD, loss of access or an adverse event, after at least 16 weeks of dupilumab treatment. In an interim analysis of data from 22 patients, comprising the intent-to-treat (ITT) population, that were randomized 2:1 active to placebo, 17 patients completed the 16-week treatment period and five patients (two in the active arm and three in the placebo arm) discontinued before the completion of the 16-week treatment period3.
Patients treated with eblasakimab 400mg once weekly (n=15) saw a rapid onset of action in the first few weeks of treatment, with a statistically significant improvement in EASI score by Week 4 (p=0.0169) compared to placebo (n=7). By Week 16, a 86.9% mean reduction4 in EASI score from baseline was observed for eblasakimab-treated patients compared to a 51.2% reduction for placebo (p=0.0059). Clinically meaningful improvements were achieved in other key efficacy measures compared to placebo at Week 16, including:
73.3% (11/15) of eblasakimab-treated patients achieved EASI-75, versus 14.3% (1/7) on placebo (p=0.0431).
60.0% (9/15) of eblasakimab-treated patients achieved EASI-90, versus 14.3% (1/7) on placebo (p=0.1278).
20.0% (3/15) of eblasakimab-treated patients achieved EASI-100, versus 0% (0/7) on placebo (EASI-100 was not a pre-specified endpoint).
66.7% (10/15) of eblasakimab-treated patients achieved a vIGA score of 0 or 1, versus 14.3% (1/7) with placebo (p=0.0750).
58.9% mean reduction in peak pruritus numerical rating scale (PP-NRS) score for eblasakimab-treated patients, versus a 12.9% reduction for placebo (p=0.0015). 53.8% (7/13) of eblasakimab-treated patients, with a baseline score of at least 4, achieved a 4-point reduction in PP-NRS score, versus 14.3% (1/7) on placebo (p=0.2460).
Of the six patients treated with eblasakimab who previously had an inadequate response to dupilumab, 66.7% (4/6) achieved EASI-90 and 66.7% (4/6) achieved a vIGA score of 0 or 1.
Treatment was well-tolerated and no new safety signals were identified. There were no reports of conjunctivitis or injection site reactions in the active or placebo arm.
Summary of data from subgroup with baseline EASI score of 18 or above
As previously announced, the TREK-DX recruitment criteria were tightened in October 2023 to enroll only patients with a baseline EASI score of 18 or above. These more stringent criteria will be the basis of analysis in the topline readout, expected at the end of 2024. Of the 22 patients in this interim analysis, 15 meet these amended enrollment criteria, and have the following efficacy findings at Week 16:
89.2% mean reduction in EASI score from baseline for eblasakimab-treated patients, versus a 45.7% reduction for placebo (p=0.0045).
83.3% (10/12) of eblasakimab-treated patients achieved EASI-75, versus 0% (0/3) on placebo (p=0.0556).
66.7% (8/12) of eblasakimab-treated patients achieved EASI-90, versus 0% (0/3) on placebo (p=0.1667).
25% (3/12) of eblasakimab-treated patients achieved EASI-100, versus 0% (0/3) on placebo (EASI-100 was not a pre-specified endpoint).
75.0% (9/12) of eblasakimab-treated patients achieved a vIGA score of 0 or 1, versus 0% (0/3) with placebo (p=0.1111).
61.2% mean reduction in PP-NRS score for eblasakimab-treated patients, versus a 1.5% increase for placebo (p=0.0004). 60% (6/10) of eblasakimab-treated patients, with a baseline score of least 4, achieved a 4-point reduction in PP-NRS score, versus 0% (0/3) on placebo (p=0.2000).
The interim data will be submitted for presentation at an upcoming scientific conference.