# EDGAR Filing Document

**Accession Number:** 0001855129
**File Stem:** 0001140361-25-026850
**Filing Date:** 2025-7
**Character Count:** 31183
**Document Hash:** fcc7cb10ff0282785e808a1d156de3f0
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001140361-25-026850.hdr.sgml**: 20250723

**ACCESSION NUMBER**: 0001140361-25-026850

**CONFORMED SUBMISSION TYPE**: 6-K

**PUBLIC DOCUMENT COUNT**: 23

**CONFORMED PERIOD OF REPORT**: 20250723

**FILED AS OF DATE**: 20250723

**DATE AS OF CHANGE**: 20250723

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** GH Research PLC
- **CENTRAL INDEX KEY:** 0001855129
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** L2
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 6-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-40530
- **FILM NUMBER:** 251141664

**BUSINESS ADDRESS:**
- **STREET 1:** JOSHUA DAWSON HOUSE
- **STREET 2:** DAWSON STREET
- **CITY:** DUBLIN 2
- **STATE:** L2
- **ZIP:** D02 RY95
- **BUSINESS PHONE:** 353 1 437 8334

**MAIL ADDRESS:**
- **STREET 1:** JOSHUA DAWSON HOUSE
- **STREET 2:** DAWSON STREET
- **CITY:** DUBLIN 2
- **STATE:** L2
- **ZIP:** D02 RY95

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UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549

### FORM 6-K

#### REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER

#### THE SECURITIES EXCHANGE ACT OF 1934

For the month of July, 2025.

#### Commission File Number: 001-40530

## GH Research PLC

#### (Exact name of registrant as specified in its charter)

#### Joshua Dawson House

#### Dawson Street

#### Dublin 2

#### D02 RY95

#### Ireland

#### (Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Form 20-F <u> ☒ </u> Form 40-F  

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#### INFORMATION CONTAINED IN THIS REPORT ON FORM 6-K

On July 23, 2025, GH Research PLC (the "Company") announced global pivotal program plans and further development updates. A copy of the press release is exhibited hereto as Exhibit 99.1 and a copy of the GH Research R&D Update is attached hereto as Exhibit 99.2.

The fact that this press release and GH Research R&D Update are being made available should not be deemed an admission as to the materiality of any information contained in the materials. The information contained in the press release and GH Research R&D Update are being provided as of July 23, 2025, and the Company does not undertake any obligation to update the press release or either presentation in the future or to update forward-looking statements to reflect subsequent actual results.

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#### EXHIBIT INDEX

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| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| [99.1](ef20052285_ex99-1.htm) | Press release dated July 23, 2025 |
| [99.2](ef20052285_ex99-2.htm) | GH Research R&D Update for July 23, 2025 |

---

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#### SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

---

| | | |
|:---|:---|:---|
|  | **GH Research PLC** | **GH Research PLC** |
| Date: July 23, 2025 |  |  |
|  | By: | /s/ Julie Ryan |
|  | Name: | Julie Ryan |
|  | Title: | Vice President, Finance |

---

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## Exhibit 99.1

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**Exhibit 99.1**<br>

#### 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, Ireland, July 23, 2025** – 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 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<0.0001).

The full analysis of the open-label extension (OLE) confirms a 73% remission rate at 6 months with infrequent treatment visits and no mandated psychotherapeutic intervention. GH001 delivered consistent MADRS reduction with re-treatments as needed. 57.5% of patients achieved remission at day 8 and 90% of those were also in remission at month 6.

Safety analysis confirmed that 100% of patients from the double-blind (DB) part continued in the OLE and there were no treatment related serious adverse events across the full 6-month duration of the trial. No treatment-emergent events of suicidal intent or suicidal behaviour occurred throughout the 6-month duration of the trial and lower rates of suicidal ideation were observed during the study in comparison to baseline. The psychoactive experience had a median duration of 11 minutes across the DB and OLE parts of the trial.

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Across the DB and OLE, patients were deemed discharge ready by 1 hour from dose administration at 99% of treatment visits. A majority of patients needed 1-2 doses of GH001 suggesting a 2-hour visit or less in a commercial setting.

#### GH002 Update
We have previously announced the completion of a Phase 1, dose-ranging clinical pharmacology trial of GH002, our proprietary intravenous mebufotenin HBr product candidate, in healthy volunteers.

Top-line results demonstrate that GH002 was well-tolerated with no severe or serious adverse events and produced ultra-rapid psychoactive effects. The pharmacokinetic profile of GH002 was equivalent to that of GH001. We expect to submit an IND with the FDA for GH002 in Q4 2025.

#### Global Pivotal Program Plans
Pivotal program planning has been ongoing since Q1 2025:

<br> • We have established a steering committee with KOLs to review Phase 2b results and assist with design of pivotal program;

<br> • CRO and site selection process is ongoing and we are ramping up the team with laser focus on execution; and

<br> • We are in the process of getting regulatory input on phase 3 requirements and preparation for end-of-phase 2 meeting is underway.

On that basis, we expect to initiate our global pivotal program in 2026.

#### About GH Research PLC
GH Research PLC is a clinical-stage biopharmaceutical company dedicated to transforming the lives of patients by developing a practice-changing treatment in depression. GH Research PLC's initial focus is on developing its novel and proprietary mebufotenin therapies for the treatment of patients with treatment-resistant depression (TRD). Based on the observed clinical activity in our Phase 2b trial, where the primary endpoint was met with a MADRS reduction from baseline of -15.5 points compared with placebo on Day 8 (p<0.0001), we believe that our mebufotenin product candidates have potential to change the way TRD is treated today.

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#### Forward-Looking Statements
This press release contains statements that are, or may be deemed to be, forward-looking statements. All statements other than statements of historical fact included in this press release, including statements regarding the clinical hold on GH001, including plans and expectations for progressing any nonclinical programs and any other work needed to lift the continuing clinical hold and the timing required for the FDA to lift such clinical hold; our plans and expectations with respect to progressing development of GH002 including with respect to the timing, scope and likelihood of IND submission and approval with the FDA; our targets regarding the initiation of our first global pivotal program; our future results of operations and financial position, business strategy, product candidates, medical devices required to deliver these product candidates, research pipeline, ongoing and currently planned preclinical studies and clinical trials, regulatory submissions and approvals and their effects on our business strategy, our expectations related to commencing trials in the US, research and development costs, cash runway, timing and likelihood of success, as well as plans and objectives of management for future operations, are forward-looking statements. Forward-looking statements appear in a number of places in this press release and include, but are not limited to, statements regarding our intent, belief or current expectations. Forward-looking statements are based on our management's beliefs and assumptions and on information currently available to our management. Such statements are subject to risks and uncertainties, and actual results may differ materially from those expressed or implied in the forward-looking statements due to various factors, including, but not limited to, the risk that the FDA does not accept our responses to the clinical hold issues and that we will be unable to fully address the FDA's concerns and lift the clinical hold on GH001; the risk that we may not be able to submit an IND for GH002 or to commence clinical trials in the United States on the timelines we are targeting; those described in our filings with the U.S. Securities and Exchange Commission. No assurance can be given that such future results, plans, or expectations or targets will be achieved. Such forward-looking statements contained in this press release speak only as of the date hereof. We expressly disclaim any obligation or undertaking to update these forward-looking statements contained in this press release to reflect any change in our expectations or any change in events, conditions, or circumstances on which such statements are based unless required to do so by applicable law. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.

#### Investor Relations
Julie Ryan

GH Research PLC

<u>investors@ghres.com</u>

 

<br> ------

<u> </u>

## Exhibit 99.2

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**Exhibit 99.2**<br>

**** <br> ![](ef20052285_ex99-2slide1.jpg)

GH Research R&D Update July 2025

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![](ef20052285_ex99-2slide2.jpg)

This presentation has been prepared by GH Research PLC ("GH Research"). Nothing contained in this presentation is, or should be construed as, a recommendation, promise or representation by the presenter or GH Research or any director, employee, agent, or adviser of GH Research. This presentation does not purport to be all-inclusive or to contain all of the information you may desire. This presentation does not constitute an offer to sell or the solicitation of an offer to buy securities, nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. This presentation contains statements that are, or may be deemed to be, forward-looking statements. All statements other than statements of historical fact included in this presentation, including statements regarding the clinical hold on GH001, including plans and expectations for progressing any nonclinical programs and any other work needed to lift the continuing clinical hold and the timing required for the FDA to lift such clinical hold; our plans and expectations with respect to progressing development of GH002 including with respect to the timing, scope and likelihood of IND submission and approval with the FDA; our targets regarding the initiation of our first global pivotal program; our future results of operations and financial position, business strategy, product candidates, medical devices required to deliver these product candidates, research pipeline, ongoing and currently planned preclinical studies and clinical trials, regulatory submissions and approvals and their effects on our business strategy, our expectations related to commencing trials in the US, research and development costs, cash runway, timing and likelihood of success, as well as plans and objectives of management for future operations, are forward-looking statements. Forward-looking statements appear in a number of places in this presentation and include, but are not limited to, statements regarding our intent, believe or current expectations. Forward-looking statements are based on our management's beliefs and assumptions and on information currently available to our management. Such statements are subject to risks and uncertainties, and actual results may differ materially from those expressed or implied in the forward-looking statements, due to various factors, including but not limited to, the risk that the FDA does not accept our responses to the clinical hold issues and that we will be unable to lift the clinical hold on GH001; the risk that we may not be able to submit an IND for GH002, or to commence clinical trials in the United States on the timelines we are targeting; and other factors, risks and uncertainties described in our filings with the U.S. Securities and Exchange Commission. No assurance can be given that such future results, plans, or expectations or targets will be achieved. Such forward-looking statements contained in this presentation speak only as of the date of this presentation. We expressly disclaim any obligation or undertaking to update these forward-looking statements contained in this presentation to reflect any change in our expectations or any change in events, conditions, or circumstances on which such statements are based unless required to do so by applicable law. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements. Disclaimer Regarding Forward-Looking Statements 2 2025© GH Research PLC

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![](ef20052285_ex99-2slide3.jpg)

Summary of GH Research R&D Updates 1 2 3 On Track to Commence TRD Pivotal Program in 2026 Strong and Consistent Final Data from GH Mebufotenin in TRD Best in Class, Best in Molecule, Best in Therapeutic Category GH001 & GH002 Formulations: Progress Update Note: To-date, no head-to-head comparisons of any other products to any of our product candidates in any clinical trial have been completed; results have been obtained from different trials with different designs, endpoints and patient populations; results may not be comparable Abbreviations: TRD = Treatment-Resistant Depression

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![](ef20052285_ex99-2slide4.jpg)

GH001 Update IND Hold Response from the FDA received. Only one hold topic remaining - the FDA requested that we either provide additional data or further justification related to the respiratory tract histology findings in rats. We strongly believe, based on scientific evidence, that the respiratory tract histology findings are rat specific. There were no additional requests related to dog toxicology. There were no device related issues remaining. Next Steps Bolster rat specificity response with additional expert opinion, available data and arguments. Engage with FDA on IND complete response. We are actively working to address the remaining issue. 4

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![](ef20052285_ex99-2slide5.jpg)

Phase 2b Trial with an Open-Label Extension in Patients with Treatment-Resistant DepressionFull Analysis Set // Efficacy Clinicaltrials.gov ID: NCT05800860 1 2 3 On Track to Commence TRD Pivotal Program in 2026 Strong and Consistent Final Data from GH Mebufotenin in TRD Best in Class, Best in Molecule, Best in Therapeutic Category GH001 & GH002 Formulations: Progress Update GH001-TRD-201 Phase 2b TrialFull Analysis Set / New Data

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![](ef20052285_ex99-2slide6.jpg)

Primary Endpoint: GH001 Led to Mean MADRS Reduction from Baseline of -15.5 on Day 8a vs Placebo (P<0.0001) a. FDA Guidance notes that efficacy with rapid-acting antidepressants generally should be demonstrated within 1 week, supporting a primary efficacy endpoint within this timeframe.1 Abbreviations: BL = Baseline; FDA = Food and Drug Administration; H = Hours; LS = Least squares; MADRS = Montgomery-Åsberg Depression Rating Scale; SE = Standard error. 1. FDA Guidance: Major Depressive Disorder: Developing Drugs for Treatment. https://www.fda.gov/media/113988/download. Accessed on 26 June 2025. LS mean difference vs placebo: -15.5 (P<0.0001) Effect size: Cohen's d = -2.0 LS Mean (±SE) Change from Baseline in MADRS Total Score BL 2H Day 2 Day 8 GH001 (n=40) Placebo (n=41) 6

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![](ef20052285_ex99-2slide7.jpg)

Double-blind n=40 patients who received GH001 OLE n=63 OLE completersa Day 8 Month 6b 73% Remission Rate at 6 Months in OLE Completers a. 63 patients who received active drug and completed the 6-month OLE per protocol (18 patients who terminated early are excluded), in DB one early termination (n=1) due to TEAE, b. Approximately 6 months post-study start (median 168 days from Day 1 of double-blind period). c. MADRS total score ≤10. Abbreviations: MADRS = Montgomery-Åsberg Depression Rating Scale; OLE = Open-label extension; TEAE = Treatment-emergent adverse event. 7 FINAL DATA

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![](ef20052285_ex99-2slide8.jpg)

Remission on Day 8 / Remission at 6 Months a. Remission defined as a MADRS total score ≤10 b. '6 Months' or 'Month 6' (end of trial) was at approximately 6 months post-study start (mean 168 days from Day 1 of double-blind period) c. Patients who completed the 6-month open-label extension follow-up per protocol (patients who terminated early are excluded), N=63 patients in total d. 90% of the OLE Completers who had remission at Day 8 after first GH001 treatment also had remission at 6 Months Abbreviations: OLE = Open-Label Extension Patients who had remission on Day 8 after their first GH001 treatment had a 90% remission rate at 6 Monthsd. 8 FINAL DATA

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![](ef20052285_ex99-2slide9.jpg)

GH001 Based on ICER estimate Treatment visits in 6 months 4 visitsa 23 visitsc 73.0% remission at 6 monthsb 83% Fewer Treatment Visits with GH001 than with Spravato Note: To-date, no head-to-head comparisons of any other products to any of our product candidates in any clinical trial have been completed; results have been obtained from different trials with different designs, endpoints and patient populations; results may not be comparable a. Four GH001 visits deduced from mean total number of treatments received across double-blind and OLE parts by OLE completers in remission at 6 months. b. '6 Months' (end of trial) was at approximately 6 months post-study start (median 168 days from Day 1 of Double-Blind period). c. SPRAVATO®: Assumes 23 treatment visits, as per standard initiation protocol of 8 & 4 sessions in months 1 & 2, respectively, and ICER assumed maintenance treatment frequency of 2.86 treatments per month for months 3-6.1,2,3 Remission defined as MADRS ≤10; Spravato 32-Week remission rates from ESCAPE-TRD trial were 49.1% remission at 32 weeks (55.0% with LOCF method).4 Abbreviations: ICER = Institute for Clinical and Economic Review; LOCF = Last Observation Carried Forward; MADRS = Montgomery-Åsberg Depression Rating Scale; OLE = Open-label extension. Sources: 1. Johnson & Johnson Spravato Access, Coding and Reimbursement Guide; 2. ICER Spravato Final Evidence Report; 3. Janssenscience.com, Dosage and Administration of Spravato, Duration of Therapy; 4. Reif et al., N Engl J Med 2023. 9 FINAL DATA

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![](ef20052285_ex99-2slide10.jpg)

Patients Discharge Ready Within 1 Hour of Dose at 99% of Visits (DB & OLE) Abbreviations: DB = Double-blind; OLE = Open-label extension; h = Hour 10 In total, only 2 patients across 3 visits not discharge ready at 1h Data from >250 GH001 treatment visits and 81 patients NEW DATA % of GH001 Treatment Visits where Patients were Discharge Ready within 1 Hour 99% 97% 100% 98% 100% 100% 99%

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![](ef20052285_ex99-2slide11.jpg)

a. 3 events resolved within 24 hours: 2 events of fatigue and 1 of nausea; b. 3 events resolved within 72 hours: 1 of headache, 1 of memory impairment and 1 of tearfulness; c. 1 event (headache) lasted for longer than 72 hours TEAEs were classified according to the Medical Dictionary of Regulatory Activities (MedDRA Version 26.0) Abbreviations: AE = Adverse event; TEAE = Treatment-emergent adverse event. Safety Data: Duration of Treatment Emergent Adverse Events (TEAEs) (Double-Blind Part) 11 Duration of TEAEs Reported at Least Twice After GH001 Administration (N=59) Patients, n (%) GH001 (n=40) Placebo (n=41) Nausea 17 (42.5) 0 (0) Salivary hypersecretion 8 (20.0) 0 (0) Paresthesia 8 (20.0) 0 (0) Headache 3 (7.5) 1 (2.4) Dysgeusia 3 (7.5) 0 (0) Most Common TEAEs (occurring in >5% of patients in either group) by Preferred Term All TEAEs observed in the double-blind part were mild to moderate a b c NEW DATA

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![](ef20052285_ex99-2slide12.jpg)

Treatment-Emergent Adverse Events of Special Interest (AESI) (Double-Blind Part) Abbreviations: AESI = Adverse Event of Special Interest; TEAE = Treatment-emergent adverse event. 12 NEW DATA GH001 (n=40) Placebo (n=41) Primary System Organ Class Preferred Term Patients n (%) Events n Patients n (%) Events n Any Treatment-Emergent AESI 8 (20.0) 10 0 0 Psychiatric disorders 5 (12.5) 6 0 0 Affect Lability 1 (2.5) 1 0 0 Anxiety 1 (2.5) 1 0 0 Confusional State 1 (2.5) 1 0 0 Emotional disorder 1 (2.5) 1 0 0 Euphoric mood 1 (2.5) 1 0 0 Hallucination, visual 1 (2.5) 1 0 0 Nervous system disorders 3 (7.5) 4 0 0 Memory impairment 2 (5.0) 3 0 0 Somnolence 1 (2.5) 1 0 0 No TEAEs of flashbacks were reported

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![](ef20052285_ex99-2slide13.jpg)

Abbreviations: SAE = Serious adverse event; TEAE = Treatment-emergent adverse event. No treatment-related SAEs during the 6-month duration of the trial No TEAEs of suicidal intent or suicidal behaviour occurred throughout the 6-month duration of the trial Lower rates of suicidal ideation were observed during the study in comparison to baseline 13 Topline Safety Data - 6 months Open Label Extension SAEs Suicidality NEW DATA

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![](ef20052285_ex99-2slide14.jpg)

Shortest psychoactive experience amongst therapeutic class for TRD, supports: Reduced requirement for clinic staff in the dosing room in commercial set up Shorter to discharge readiness Rapidly-resolving TEAEs GH001 2h 3h 4h 5h 6h Median Duration of the Psychoactive Experience of 11 minutes (DB & OLE treatments) BPL-003a VLS-01b COMP360c 11 min median 1h Duration of Psychoactive Experience (approximate average) Note: To-date, no head-to-head comparisons of any other products to any of our product candidates in any clinical trial have been completed; results have been obtained from different trials with different designs, endpoints and patient populations; results may not be comparable a. Assumption of BPL-003 duration of ~90min psychoactive phase from Phase 1 SDI results as reported in Rucker et al., 2024; b. VLS-01 duration of ~120min psychoactive experience from Phase 1b results, mean SIRS scores graph, data for 120mg dose (atai Life Sciences Corporate Presentation, July 2025); c. COMP360 duration of ~6h from Compass Pathways website, which states "The psilocybin experience typically lasts 6 to 8 hours" Abbreviations: DB = Double-blind; OLE = Open-label extension; h = Hours; min = minutes; SDI = Subjective Drug Intensity; SIRS = Subjective Intensity Rating Scale; TRD = Treatment-resistant depression; TEAE = Treatment Emergent Adverse Event 45-90min ~120min 6-8 hours NEW DATA 14

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![](ef20052285_ex99-2slide15.jpg)

Potential for GH Mebufotenin in TRD Best in Molecule Fast in Fast out (FIFO) formulations shown to be better than slower release formulations (intranasal) 15,5 vs 5 pbo corrected No psychotherapy needed Minimal Aes , minimal psychoactive phase Best in Class GH formulations shown far better efficacy than any other psychedelic and at the same time the shortest psychoactive period Best in Therapeutic Category Pbo adjusted effects of 15.5 MADRS points is best in therapeutic Category, and achieved intraday. Repeat dosing yields same effect, and on-demand dosing feasible with long effect window, and no SAEs. Best in Therapeutic Category (TRD) PBO-adjusted MADRS reduction: 15.5 with GH001 vs 6.8 with Spravato Monotherapya vs ~4 with Oral ATDb Day 2 Remission: 70% with GH001 vs 15.1% with Spravatoc vs ~14% with oral ATDd Number of Treatments: 4 with GH001 vs 23 with Spravatoe over 6 months Best in Class (Psychedelics) PBO-adjusted MADRS reduction: 15.5 with GH001 vs 3.6 with COMP360 (phase 3 data)f Length of PsE: Median of 11 mins with GH001 vs 6-8 hours for COMP360h vs 45-90 mins for BPL-003g No Additional Psychotherapy / Therapists Visits with GH001 Best in Molecule (5-MeO-DMT) Remission rates at Day 8: 57.5% with GH001 vs 26% with BPL-003 8mg dosei Length of PsE: Median of 11 mins with GH001 vs 45-90 mins for BPL-003g No Additional Psychotherapy / Therapists Visits with GH001 Note: To-date, no head-to-head comparisons of any other products to any of our product candidates in any clinical trial have been completed; results have been obtained from different trials with different designs, endpoints and patient populations; results may not be comparable. a. Spravato monotherapy data for 84mg dose from TRD4005 trial, presented at ECNP 2024; b. Auvelity, data at week 6 GEMINI trial, Iosifescu et al., 2022; c. TRD4005 trial, Janik et al. 2025 d. STAR\*D data Rush et al. 2006 e. Assumes 23 treatment visits, as per standard initiation protocol of 8 & 4 sessions in months 1 & 2, respectively, and ICER assumed maintenance treatment frequency of 2.86 treatments per month for months 3-6.See slide 9. f. Compass Pathways PR June 23, 2025; g. BPL-003 duration assumption from Phase 1 SDI results as reported in Rucker et al., 2024; h. COMP360 duration assumption from Compass Pathways website, which states "The psilocybin experience typically lasts 6 to 8 hours", i. Atai Corporate Deck, July 2025 Abbreviations: TRD = Treatment-Resistant Depression; ATD = Antidepressant; PBO = Placebo; MADRS = Montgomery-Åsberg Depression Rating Scale; PsE = Psychoactive Experience 15

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![](ef20052285_ex99-2slide16.jpg)

Summary of GH Research R&D Updates 1 2 3 On Track to Commence TRD Pivotal Program in 2026 Strong and Consistent Final Data from GH Mebufotenin in TRD Best in Class, Best in Molecule, Best in Therapeutic Category GH001 & GH002 Formulations: Progress Update

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![](ef20052285_ex99-2slide17.jpg)

Two 'Fast-in-Fast-Out' Mebufotenin Formulations GH001 (Inhaled Mebufotenin) T1/2 =y cmax = z, psychoactive period = 10-15m Regulatory status: UK MHRA approval and cross over study completed with new device US: IND resubmitted. Received response letter clearing 3 of 4 issues. Call for more data and arguments, both which are in house available and will be submitted imminently. Resolution expected q3/q4 2025. next steps prior to pivotal are XYZ GH002 (I.V. Mebufotenin) T1/2=x cmax = y, psychoactive period = 10-15m Healthy Volunteer study completed More on Status here. Next Steps prior to pivotal program MAKE CLEAR WHY YOU WOULD BE IN POSITION TO CHOSE Final PIVOTAL FORMULATION IN Q2 2026 or whatever date is best. i.e. make sure the individual steps for the 2 FIFO formulations align with this GH001 (Inhaled Mebufotenin, Free Base) Expected Pivotal Program Start: 2026 Ongoing Pivotal Program preparation activities currently synergistic across GH001 and GH002 programs Status: Phase 1 dose ranging study in HVs completed Comparative PK equivalence with inhaled formulation - achieved Doses for next phase of development selected Patent protected Next steps for Pivotal Program Readiness: IND submission expected Q4 2025 Status: Phase 2b study in TRD completed Bridging HV study with GH proprietary device in progress (UK) Engagement with FDA on IND complete response ongoing: Only one hold topic remaining - related to the respiratory tract histology findings in rats. No additional requests related to dog toxicology. No device related issues remaining. Patent protected Next steps for Pivotal Program Readiness: EoP2 meeting with FDA/EMA Scientific Advice GH002 (IV Mebufotenin, HBr Salt) Abbreviations: IV = intravenous; HBr = Hydrobromide; HV = Healthy Volunteer; TRD = Treatment-Resistant Depression; IND = Investigational New Drug; FDA = U.S. Food and Drug Administration; EMA = European Medicines Agency; EoP2 = End of Phase 2; PK = Pharmacokinetics

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![](ef20052285_ex99-2slide18.jpg)

Summary of GH Research R&D Updates 1 2 3 On Track to Commence TRD Pivotal Program in 2026 Strong and Consistent Final Data from GH Mebufotenin in TRD Best in Class, Best in Molecule, Best in Therapeutic Category GH001 & GH002 Formulations: Progress Update

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![](ef20052285_ex99-2slide19.jpg)

On Track to Commence TRD Pivotal Program in 2026 Abbreviations: TRD = Treatment-Resistant Depression; RoW = Rest of World; CRO = Contract Research Organisation; HTA = Health Technology Assessment Body; EoP2 = End of Phase 2 Pivotal Program Design building on Ph2b Results Site selection in US, EU and RoW underway CRO Selection underway Steering Committee (US & EU) formed and operational Payer & HTA input in-process Regulatory requirements input in process Team ramp-up with laser-focus on execution Preparation for EoP2 underway ONGOING since Q1 2025

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![](ef20052285_ex99-2slide20.jpg)

Summary of GH Research R&D Updates 1 2 3 On Track to Commence TRD Pivotal Program in 2026 Strong and Consistent Final Data from GH Mebufotenin in TRD Best in Class, Best in Molecule, Best in Therapeutic Category GH001 & GH002 Formulations: 2 PK Equivalent Solutions 4 $315.3 million cash and investments as of March 31, 2025 to execute Note: To-date, no head-to-head comparisons of any other products to any of our product candidates in any clinical trial have been completed; results have been obtained from different trials with different designs, endpoints and patient populations; results may not be comparable Abbreviations: TRD = Treatment-Resistant Depression

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