Eupraxia EoE drug shows >90% inflammation cut in Phase 1b/2a data

Eupraxia Pharmaceuticals has released the first sub-score data from its Eosinophilic Esophagitis Histology Scoring System (EoEHSS) analysis within the ongoing Phase 1b/2a RESOLVE trial, presenting results at Digestive Disease Week (DDW) in Chicago on 6 May. The Vancouver-based, NASDAQ-listed company said its locally delivered candidate EP-104GI demonstrated improvements in both inflammation and fibrosis measures across the majority of patient cohorts at 12 and 36 weeks.

EoEHSS is a validated, standardised tool comprising eight individual features — four assessing inflammation (EoEHSS-i) and four evaluating architectural and fibrotic changes (EoEHSS-a). Each sub-score captures both the grade and stage of disease, making it a more granular readout than simple eosinophil counts alone.

Key data

In the Phase 1b/2a portion of RESOLVE — an open-label, dose-escalation study in adults with histologically confirmed active EoE — all reported cohorts at week 12 (n=31) and week 36 (n=27) showed improvement in EoEHSS-i. Improvements in EoEHSS-a were seen across most cohorts at both timepoints. The strongest responses occurred at the highest dose tested, cohort 9 (20x8mg), where the improvement in the inflammatory sub-score grade and stage exceeded 90% at both 12 and 36 weeks, and the architectural and fibrosis sub-score showed improvements of greater than 83% at both timepoints.

Chief executive James Helliwell said the sub-score results were consistent with previously reported symptom improvements and endoscopic reference score (EREFS) data. "This is consistent with the improvements we have seen in EoE symptoms and with our recently reported endoscope scoring data and suggests treatment with EP-104GI may have an important benefit for EoE patients," he said.

EP-104GI is administered as a single-dose series of four to twenty injections into the esophageal wall, using Eupraxia's proprietary Diffusphere polymer-based microsphere platform to deliver drug in a hyper-localised, extended-release manner. The approach is designed to avoid the systemic peaks and troughs associated with conventional corticosteroid therapy — currently the mainstay of EoE pharmacological management following the FDA's 2022 approval of budesonide oral suspension.

Market context and regulatory path

EoE affects an estimated 450,000 people in the United States alone and is described by the American Gastroenterological Association as rapidly growing in both incidence and prevalence. Despite budesonide and dupilumab (approved in 2022) now offering approved options, a meaningful proportion of patients do not achieve deep histological remission, leaving room for differentiated treatments — particularly those targeting fibrotic tissue remodelling alongside inflammation.

The dual inflammatory and architectural signal reported by Eupraxia is notable because fibrosis, which contributes to the strictures and swallowing difficulties characteristic of advanced EoE, is generally considered harder to reverse than eosinophilic inflammation. Whether the EoEHSS-a improvements seen in a small, open-label cohort translate into meaningful structural benefit in a controlled setting remains to be seen. The Phase 2b arm of RESOLVE — a randomised, placebo-controlled study evaluating the 120mg and 160mg doses — is currently recruiting, with top-line data expected in the fourth quarter of 2026. That readout will be the definitive test of whether the open-label signal holds.

Eupraxia said it plans to disclose further Phase 1b/2a data in the coming months ahead of the Phase 2b readout.