Company: GHRS
Filing Date: 2025-02-05
Form Type: 424B5
Source: 0001140361-25-003183
Chunk: 5

Company: GH Research PLC
Filing Date: 2025-02-05
Form: 424B5
Chunk 5
---
ission (MADRS≤10) and were responders (MADRS reduction ≥50%) at 2 hours, Day 2 and Day 8. Remission and response rates with GH001 were significantly greater than placebo at all timepoints (p<0.0001). Treatment with GH001 led to clinically and statistically significant improvements on the Clinical Global Impression Severity, or CGI-S, and Hamilton Anxiety Rating, or HAM-A, scales, and the Quality of Life Enjoyment and Satisfaction Questionnaire, or Q-LES-Q-SF Questionnaire, on Day 8, compared with placebo. As of January 22, 2025, 9 patients are ongoing in the trial, while 54 patients have completed the full 6-month follow-up of the open-label extension, or OLE, phase, and 18 patients discontinued, with one patient’s discontinuation due to an adverse event. Of the 54 patients who completed the OLE as of January 22, 2025:

| • | 77.8% of patients were in remission (MADRS≤10) at the 6 month visit and 81.5% were responders (MADRS reduction ≥50%); |

| • | Mean MADRS total score at 6 months was 8.6; |

| • | 63.0% (n=34) received 1-4 treatments with GH001; |

Safety analysis has not yet been completed for the OLE as it remains ongoing, but as of January 22, 2025, no serious adverse events have been reported throughout the OLE. Our Phase 2b clinical trial of GH001 in patients with TRD is subject to certain risks and uncertainties, as is the case with our other clinical trials. Please see Exhibit 99.1 of the Current Report on Form 6-K filed on February 3, 2025 that is incorporated by reference in this prospectus supplement for certain risk factors relevant to our clinical trials. Corporate Information GH Research PLC was incorporated as a public limited company under the laws of Ireland on March 29, 2021 to become a holding company for GH Research Ireland Limited. GH Research Ireland Limited was originally incorporated under the laws of Ireland on October 16, 2018 as GH Research Limited. GH Research Limited changed its name to GH Research Ireland Limited on March 29, 2021. Our principal place of business is located at Joshua Dawson House, Dawson Street, Dublin 2,