Why Did ASLAN Pharma Shares Plunge Despite Positive Atopic Dermatitis Trial Data?

ASLAN Pharmaceuticals Ltd ASLN has announced topline data from its Phase 1 study of ASLAN004 for moderate-to-severe atopic dermatitis (AD).
In March 2021, ASLAN announced interim data from three dose-escalation cohorts (200mg, 400mg, and 600mg).
Today's results compare all patients receiving 600mg (highest dose) to all receiving placebo (n=39). The Intent to Treat (ITT) population is n=38.
ASLAN004 achieved a statistically significant improvement versus placebo in the primary efficacy endpoint of percent change from baseline in the Eczema Area Severity Index (EASI).
The average reduction from baseline in EASI at 8 weeks was 65% (n=16) compared to 27% (n=13) for patients on placebo.
Compared to the interim data, the average reduction in eczema severity index was 74% for ASLAN004.
Related Content: Aslan Pharma Shares Are Trading Higher On Positive ASLAN004 Data In Atopic Dermatitis.
69% achieved EASI-75 versus 15% on placebo.
44% of patients achieved Investigator's Global Assessment (IGA) of 0 or 1 versus 15% on placebo (p=0.1071).
In the 32 patients that completed at least 29 days of dosing, the average reduction from baseline in EASI at 8 weeks was 73% (n=19) compared to 44% (n=13) for patients on placebo.
ASLAN is initiating a global Phase 2b study of ASLAN004 for AD and is on track to enroll the first patient in 4Q of 2021.
Price Action: ASLN stock is down 24.60% at $2.45 during the premarket session on the last check Monday.