Page 1

GH RESEARCH GH Research Reports Second Quarter 2026 Financial Results and Provides Business Update August 6 , 2026 • Alignment with FDA on CMC and device plans for Phase 3 Successfully completed GH001 - HV - 106 and GH001 - HV - 109 Phase 1 trials • Further strengthening of US and EU mebufotenin patent estate • Phase 2a results in postpartum depression published in The Journal of Clinical Psychiatry • Cash , cash equivalents and marketable securities of $ 362.7 million as of June 30 , 2026 DUBLIN , Aug. 06 , 2026 ( 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 reported financial results for the quarter ended June 30 , 2026 , and provided a business update . Business Updates Global Pivotal Program of GH001 in TRD We have completed GH001 - HV - 106 , our Phase 1 clinical pharmacology trial of our proprietary aerosol delivery device in healthy volunteers , and GH001 - HV - 109 , our IND - opening Phase 1 trial of GH001 in healthy volunteers in the United States . Based on the results of GH001 - HV - 106 , we have selected the doses for our pivotal program . In July 2026 , we received written responses from the FDA confirming that our CMC and device plans appear Phase 3 ready . We continue to engage with the FDA on the design of the pivotal program , which is intended to replicate the Phase 2b trial , including consideration of recent FDA guidance issued in July 2026 , and we continue to target initiation of our pivotal program in 2026 . Intellectual Property In July 2026 , the U.S. Patent and Trademark Office granted U.S. Patent No. 12,685,721 , with claims directed to methods of treating major depressive disorder ( MDD ) and treatment - resistant depression ( TRD ) , by administering an aerosol of mebufotenin , which is expected to expire no earlier than 2043. We continue to be the company with the earliest patent filings relating to treatment of MDD and TRD using mebufotenin and continue prosecution of further claims . Also in July 2026 , the main request of our European Patent No. 3 927 337 was maintained following an opposition hearing before the European Patent Office . As maintained , the patent claims mebufotenin , and salts thereof , for use in the treatment of MDD and TRD including , but not limited to , mebufotenin administered through inhalation , intravenous and intranasal routes , and is expected to expire no earlier than 2040 . Publications and Scientific Presentations In June 2026 , the full results of our Phase 2a trial of GH001 in postpartum depression were published in The Journal of Clinical Psychiatry . In addition , an analysis of our Phase 2b GH001 - TRD - 201 trial showing efficacy independent of the number of prior antidepressant treatment failures was published in Psychopharmacology Bulletin . Data from GH001 - TRD - 201 were also presented at the American Society of Clinical Psychopharmacology Annual Meeting in May 2026 and at the 37th World Congress of Neuropsychopharmacology in June 2026 , and further posters have been accepted for the International Society for Bipolar Disorders Annual Conference in September 2026 and the European College of Neuropsychopharmacology Congress in October 2026 , where we will also host an industry symposium . Second Quarter 2026 Financial Highlights Cash position Cash , cash equivalents and marketable securities were $ 362.7 million as of June 30 , 2026 , compared to $ 280.7 million as of December 31 , 2025 . Gross proceeds from the underwritten offering in Q2 2026 were $ 117.5 million . Marketable securities are comprised of investment grade bonds . Research and development expenses R & D expenses were $ 12.4 million for the quarter ended June 30 , 2026 , compared to $ 9.0 million for the same quarter in 2025. The increase is primarily due to increased clinical development expenses as well as employee expenses . General and administrative expenses G & A expenses were $ 7.1 million for the quarter ended June 30 , 2026 , compared to $ 5.7 million for the same quarter in 2025. The increase is primarily due to an increase in professional fees . Net loss Net loss was $ 15.1 million , or $ 0.23 loss per share , for the quarter ended June 30 , 2026 , compared to $ 9.3 million , or $ 0.15 loss per share , for the same quarter in 2025 . 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 TRD . About GH001 Our lead product candidate , GH001 , is formulated for mebufotenin administration via a proprietary inhalation approach . Based on the observed clinical activity in our Phase 2b GH001 - TRD - 201 trial , where the primary endpoint was met with a Montgomery - Åsberg Depression Rating Scale ( MADRS ) reduction from baseline of -15.5 points compared with placebo on Day 8 ( p < 0.0001 ) , we believe that GH001 has the potential to change the way TRD is treated today .