GH Research Announces Global Pivotal Program Plans and Further Development Updates

• Engagement with FDA on GH001 IND complete response ongoing
• The fully completed Open-Label Extension analysis confirms a 73% remission rate at 6 months with infrequent treatment visits and no psychotherapy
• Treatment was well tolerated and no treatment related serious adverse events were reported. There was no evidence of treatment-emergent suicidal ideation or behavior
• Global pivotal program initiation on track for 2026

DUBLIN, July 23, 2025 (GLOBE NEWSWIRE) -- GH Research PLC (Nasdaq: GHRS), a clinical-stage biopharmaceutical company dedicated to transforming the lives of patients by developing a practice-changing treatment in depression, today provided updates on its business and key upcoming milestones.

GH001 Update

We have recently announced that we submitted a complete response to the previously announced clinical hold on our Investigational New Drug Application (IND) for GH001 with the U.S. Food and Drug Administration (FDA). We have now received a response from the FDA with only one hold topic remaining. The FDA requested that we either provide additional data or further justification related to the previously announced respiratory tract histology findings in rats. We strongly believe, based on scientific evidence, that the respiratory tract histology findings are rat specific. There are no additional requests related to dog toxicology. There are no device related issues remaining.

Engagement with FDA on IND complete response is ongoing. We are actively working to address the remaining issue.

Final Data from Fully Completed Phase 2b TRD

Previously we reported on the initial results from the phase 2b clinical trial of GH001 in treatment-resistant depression (TRD). This included part of the open-label extension (OLE) phase. Today we can report on the full dataset.

The primary endpoint was met with a highly significant placebo adjusted reduction from baseline of -15.5 points in Montgomery-Åsberg Depression Rating Scale (MADRS) total score on Day 8 (p