The biotech firm said it would halt development of barzolvolimab in eosinophilic esophagitis following Phase 2 results that met the trial’s primary goal but failed to show clinical benefit.
Celldex Therapeutics shares slipped in after-hours trading on Tuesday after the biotech said it will stop developing barzolvolimab for eosinophilic esophagitis (EoE).
The stock closed down 1.9% at $24.02 on Tuesday and slid another 14.2% to $20.62 in after-hours trading following its Phase 2 EoE update.
The decision to pull the plug on the EoE candidate came after the Phase 2 trial hit its primary goal by reducing mast cells in the esophagus, but the depletion failed to bring meaningful improvements for patients.
No differences were observed between barzolvolimab and placebo in dysphagia symptom scores, endoscopic assessment of inflammation and fibrosis, or histological reduction in eosinophil infiltration.
Celldex said the results provide direct evidence that mast cells are not a primary driver of the disease.
The study confirmed barzolvolimab’s favorable safety and tolerability profile at the dosing regimen that was tested, consistent with prior studies where dosing was less frequent.
“While we are disappointed in the clinical outcome in EoE, we are proud of our role in advancing the science for patients who need more effective treatment options,” said Chief Executive Officer Anthony Marucci.
Marucci added that Celldex remains committed to barzolvolimab’s broader pipeline, with enrollment ongoing in four studies: two Phase 3 trials in chronic spontaneous urticaria and two Phase 2 trials in atopic dermatitis and prurigo nodularis.
The company is also finalizing plans to initiate a Phase 3 program in inducible urticaria, covering cold urticaria and symptomatic dermographism.
On Stocktwits, retail sentiment for Celldex was ‘bullish’ amid ‘high’ message volume.
One user focused on Celldex’s pivot toward chronic spontaneous urticaria (CSU), saying investors are primarily betting on the Phase 3 program after strong Phase 2 data, which they described as better than the current standard of care.
They noted that CSU represents a much larger commercial opportunity, with market leader Xolair bringing in more than $4 billion in revenue in 2024.
Another user suggested the pullback could be a buying opportunity, calling it a good time to add to positions in Celldex.
Celldex’s stock has declined 5% so far in 2025.
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