UNAUDITED CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS FOR THE THREE AND NINE MONTHS ENDED SEPTEMBER 30, 2021 GH RESEARCH PLC Condensed consolidated interim statement of comprehensive income Three months ended Sep

UNAUDITED CONDENSED CONSOLIDATED

INTERIM FINANCIAL STATEMENTS FOR THE

THREE AND NINE MONTHS ENDED

Condensed consolidated interim statement of comprehensive income

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

Condensed consolidated interim statement of financial position

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

Condensed consolidated interim statement of changes in equity

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

Condensed consolidated interim statement of cash flows

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

NOTES TO THE CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS (continued)

GH Research PLC (the "Company") was incorporated on March 29, 2021. The registered office of the Company is located at 28 Baggot Street

Lower, Dublin 2, Ireland.

The Company and its subsidiary, GH Research Ireland Limited, (together the "Group" or "GH Research") are a clinical-stage

biopharmaceutical company dedicated to transforming the treatment of psychiatric and neurological disorders. Its initial focus is on developing the novel and proprietary 5-MeO-DMT therapies for the treatment of patients with Treatment Resistant

Depression, or TRD. Its portfolio currently includes GH001, a proprietary inhalable 5-MeO-DMT product candidate, GH002, a proprietary injectable 5-MeO-DMT product candidate, and GH003, a proprietary intranasal 5-MeO-DMT product candidate.

On April 8, 2021, GH Research Ireland Limited issued 25,379,047 Series B preferred shares (which were redesignated into 10,151,618

ordinary shares of GH Research PLC prior to the closing of the initial public offering). The net proceeds of this issuance were $118.8 million, after deducting directly attributable transaction costs of $6.4 million.

On June 29, 2021, the Company completed an initial public offering ("IPO") on the Nasdaq Global Market ("Nasdaq") in which it issued and

sold an aggregate of 11,499,999 ordinary shares at $16.00 per share, which included 1,499,999 ordinary shares issued and sold pursuant to the underwriters' exercise in full of their option to purchase additional ordinary shares. The net proceeds of the

offering were $167.6 million, after deducting underwriting discounts and estimated directly attributable transaction costs of $16.4 million.

These unaudited condensed consolidated interim financial statements were presented to the board of directors and approved by them for

issue on December 6, 2021.

Basis of preparation

Compliance with International Financial Reporting Standards

The unaudited condensed consolidated interim financial statements for the three and nine months ended September 30, 2021 have been

prepared in accordance with IAS 34 "Interim Financial Reporting". The unaudited condensed consolidated interim financial statements do not include all of the information required for full annual financial statements and should be read in conjunction

with the financial statements of GH Research Ireland Limited for the year ended December 31, 2020 which were prepared in accordance with International Financial Reporting Standards ("IFRS"). These unaudited condensed consolidated interim financial

statements are presented in U.S. dollar ("USD" or "$"), which is the Company's functional currency and the Group's presentation currency.

The incorporation of GH Research PLC is accounted for as a capital reorganization and the comparatives are presented on that basis.

The financial information presented in this interim report does not represent full statutory accounts as defined by the Companies Act

2014. The statutory accounts of GH Research Ireland Limited for the year ended December 31, 2020, are expected to be filed with the Companies Registration Office by December 9, 2021. GH Research Ireland Limited was exempt from a statutory audit for the

year ended December 31, 2020.

New and amended IFRS standards

There are no new IFRS standards, amendments to standards or interpretations that are mandatory for the financial year beginning on January

1, 2021, that are relevant to the Group and that have had any impact in the interim period. New standards, amendments to standards and interpretations that are not yet effective, which have been deemed by the Company as currently not relevant, are not

GH Research is a clinical-stage biopharmaceutical company developing innovative therapeutics. The Group is exposed to all risks inherent

in establishing and developing its business, including the substantial uncertainty that current projects will succeed. Research and development expenses have been incurred from the start of the Group's activities, generating negative cash flows from

operating activities since formation.

NOTES TO THE CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS (continued)

Since its incorporation, the Group has funded its growth through capital increases. The Group has never taken bank loans nor otherwise

incurred debt on its balance sheet. As a result, the Group is not exposed to liquidity risk through requests for early repayment of loans.

As of September 30, 2021, the Group's cash amounted to $280.7 million (December 31, 2020: $5.9 million).

The board of directors believes that the Group has sufficient financial resources available to cover its planned cash outflows for at

least the next twelve months from the date of issuance of these unaudited condensed consolidated interim financial statements. The Group, therefore, continues to adopt the going concern basis in preparing its unaudited condensed consolidated interim

financial statements.

Use of estimates and judgments

The preparation of the unaudited condensed consolidated interim financial statements requires management to make judgements, estimates and

assumptions that affect the application of accounting policies and the reported amounts of assets and liabilities, income and expense. Actual results may differ from these estimates.

In preparing these unaudited condensed consolidated interim financial statements, the significant judgements made by management in

applying the Group's accounting policies and the key sources of estimation uncertainty included those that applied to the financial statements of GH Research Ireland Limited for the year ended December 31, 2020.

The accounting policies, presentation and methods of computation followed in the unaudited condensed consolidated interim financial

statements are consistent with those applied in the Group's most recent annual financial statements and have been applied consistently to all periods presented in the unaudited condensed consolidated interim financial statements.

The unaudited condensed consolidated interim financial statements incorporate the financial statements of the Company and its subsidiary,

GH Research Ireland Limited. Subsidiaries are all entities over which the Company has control. Control is achieved when the Company has power over an entity, is exposed to or has rights to variable returns from its involvement with the entity and has

the ability to affect returns through its power over the entity. Subsidiaries are fully consolidated from the date on which control is transferred to the Company. They are deconsolidated from the date that control ceases. All intercompany transactions

have been eliminated.

Foreign currency translation

The functional currency of the Company is the U.S. dollar given it is listed on NASDAQ and its fundraising activities are in U.S. dollars.

The functional currency of its subsidiary, GH Research Ireland Limited, is euro due to its expenses being mainly incurred in euro. The condensed consolidated interim financial statements are presented in U.S. dollar which is the Group's presentation

Items included in the financial statement of the Company's subsidiary are measured using the currency of the primary economic environment

in which the entity operates which is the euro.

Foreign currency transactions are translated into the functional currency using the exchange rates prevailing at the dates of the

transactions. Monetary assets and liabilities denominated in foreign currencies are retranslated at the condensed consolidated interim statement of financial position date. The subsidiary is holding a U.S. cash balance and, as a result of the

accounting treatment, when it is translated to euro in the subsidiary accounts, it results in a foreign currency translation difference in the income statement. On consolidation, the subsidiary's assets and liabilities in foreign currencies are

retranslated and the resulting foreign currency difference goes through the foreign currency translation reserve.

NOTES TO THE CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS (continued)

Property, plant and equipment

Property, plant and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the

respective assets, which are as follows:

Share-based compensation expense

The fair value of options granted under the share option plan is recognized as a share-based compensation expense with a corresponding

increase in equity. The total expense is recognized over the vesting period, which is the period over which all of the specified vesting conditions are to be satisfied.

Incremental transaction costs are capitalized as incurred and are shown in equity as a deduction, net of tax, from the proceeds received

from financing rounds and the initial public offering. If the equity instruments are not subsequently issued, the transaction costs would be expensed.

Cash represents cash held on bank current accounts and is carried at amortized cost. The Company's cash balance is maintained with well

established, highly rated financial institutions. As of September 30, 2021, the cash balance is held at one bank that has S&P's credit rating of BBB+. The majority of the cash balance is held in U.S. dollars.

Fair value estimation

At September 30, 2021, the carrying amount is considered to be identical to the fair value for the following financial assets and

- Other current assets

- Trade payables and other current liabilities

Current and deferred income tax

Taxes on income are accrued in the same periods as the revenues and expenses to which they relate. Current income tax assets and

liabilities for the current period are measured at the amount expected to be recovered from or paid to the taxation authorities. No current tax charge was recognized in the three and nine months ended 30 September 2021 and 2020, respectively, as no

amount is expected to be payable or recoverable on the taxable results for those periods.

Deferred income tax assets are recognized only to the extent that it is probable that future taxable profit will be available against

which the temporary differences or the unused tax losses can be utilized. Deferred income tax assets from tax credit carry-forwards are recognized to the extent that the national tax authority confirms the eligibility of such a claim and that the

realization of the related tax benefit through future taxable profits is probable.

Management considers the Group to have only a single segment: Research and Development ("R&D"). This is consistent with the way that

information is reported internally within the Group for the purpose of allocating resources and assessing performance.

NOTES TO THE CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS (continued)

During the three and nine months ended September 30, 2021 and 2020, the Company incurred research and development expenses as follows:

The increase in external costs relates to the increase in technical development and clinical trial activity. The increase in employee