Aslan fails to roar with atopic dermatitis data
Dupixent has set such a high bar in atopic dermatitis anyone coming for its crown had better come prepared. This could be why questions around Aslan Pharmaceuticals' trial design and results contributed to a 31% fall in the group’s share price. In the phase 1 trial a 600mg dose of ASLAN004 showed a statistically significant 65% change in skin clearance from baseline at week 8. However, there were concerns about the removal of nine patients from the original intent-to-treat population and the study using a one-sided p value. Perhaps more worrying was that the number of patients achieving a IGA score of 0/1, ie clear or almost clear skin, was not significant at 48.3% versus 15.4% for placebo (p=0.107); this is important as the IGA 0/1 score is used for US approval. Arguably the sample size of 29 – reduced from 38 – was not powered to show a definitive result, but the result also appeared to show reduced efficacy; in March 22% of patients achieved IGA or 0/1, compared with 0% on placebo. Aslan is looking to begin a phase 2 trial before the end of the year and one concern is that what looks like waning efficacy could be exacerbated with larger numbers.
|ASLAN004 phase 1 trial|
|Endpoint (8 weeks)||RITT (n=29)||ITT (n=38)|
|Mean % change from baseline in EASI||-64.9||-27.2||0.021||-61.3||-31.9||0.023|
|IGA 0/1 (%)||43.8||15.4||0.107||31.8||18.8||0.301|
|Mean % change from baseline in peak pruritus||-38.6||-15.3||0.051||-37.1||-15.7||0.032|
|RITT = revised intent to treat; p-value1 (one-sided p-value). Source: Company announcement.|