Half-year Results

Strong operational progress as TOPICAL trial builds momentum

29 September 2026 - Poolbeg Pharma (AIM: POLB, 'Poolbeg' or the 'Company'), a clinical-stage biopharmaceutical company with a core focus on transforming the cancer immunotherapy field, announces its unaudited interim results for the six months to 30 June 2026.

Highlights & Updates

TOPICAL trial initiated following MHRA Clinical Trial Authorisation ("CTA"), with eight of c.30 participants dosed to date. Recruitment activity remains encouraging, with strong engagement from investigators, participating centres and patients.

Strong financial position maintained, with cash balance of £4.8 million as at 30 June 2026, further strengthened post period end by a fundraise of £3.5 million (before expenses) completed in July 2026. This funds both the POLB 001 TOPICAL trial and the oral GLP-1 proof-of-concept trial through to completion and extends the cash runway into Q2 2028.

Positive FDA pre-IND meeting, with alignment on POLB 001's development pathway and future Phase 3 primary endpoint.

Preclinical data presented at the European Hematology Association ("EHA") 2026 Congress supporting POLB 001 as a potential preventative therapy for cancer immunotherapy-induced Cytokine Release Syndrome ("CRS"), together with a poster from The University of Manchester indicating POLB 001's potential to enhance the efficacy of azacitidine in aged models of acute myeloid leukaemia.

Independent US payer research, covering payers representing c.75 million lives, found willingness to pay at commercially meaningful price points, supporting multi-billion-dollar US peak sales potential for POLB 001.

Results of the LPS challenge study were published in full in Frontiers in Immunology, a leading peer-reviewed journal. Study demonstrated potent p38 MAPK inhibition, safety and tolerability of POLB 001 and positive impact on a range of key inflammatory biomarkers.

Global intellectual property portfolio strengthened, including the first patent grants within Poolbeg's cancer immunotherapy-induced CRS patent family, now granted in Canada, Australia and Europe and allowed in Israel.

Strengthened Scientific Advisory Board with the appointment of oncology and cell therapy expert Dr Adrian Kilcoyne.

Post period, the TOPICAL trial was recommended to continue as planned following a positive review of the six-patient interim safety cohort, with no changes required to the study protocol.

Jeremy Skillington, PhD, Chief Executive Officer of Poolbeg Pharma, said:

"The first half of 2026 saw POLB 001 progress from TOPICAL trial preparation into execution, and we have built on that momentum since the period end. Eight patients have now been dosed in the TOPICAL trial and, following a positive review of data from the interim safety cohort, the study will continue as planned.

"POLB 001 has the potential to be the first approved preventative therapy for cancer immunotherapy-induced CRS. Positive FDA pre-IND feedback, a growing patent estate and independent US payer research all support its partnering potential.

"With both clinical programmes funded through to completion, we believe Poolbeg is well positioned for its next phase of value creation."

CEO Statement

The first half of 2026 marked a significant period of progress for Poolbeg as we successfully advanced POLB 001 through a series of regulatory, operational and commercial milestones.

POLB 001 is being developed as a potential first approved preventative therapy for cancer immunotherapy-induced Cytokine Release Syndrome ("CRS"). We believe POLB 001 has the potential to address a significant unmet medical need and support broader access to certain cancer immunotherapies by reducing the incidence of CRS, a serious and potentially life-threatening side effect that can limit treatment availability and increase healthcare burden.

During the period, we strengthened the programme on multiple fronts. We secured MHRA Clinical Trial Authorisation for the TOPICAL trial and were delighted to have leading sites from across the UK participating. In parallel, a positive pre-IND meeting with the FDA provided greater clarity on the US development pathway for POLB 001, supporting our ongoing partnering discussions.

Independent US payer research conducted by Acumetis, reconfirmed the significant market opportunity for POLB 001 and reinforced its value proposition to healthcare systems and potential partners.

In addition, we have continued to build our global intellectual property portfolio, including securing the first national grant within our cancer immunotherapy-induced CRS patent family, an important milestone that further strengthens the protection of our IP and the future value of POLB 001.

Finally, we expanded our scientific expertise through the appointment of Dr Adrian Kilcoyne, a cancer immunotherapy and CRS expert, to our Scientific Advisory Board.

Together, these achievements have strengthened the POLB 001 package and provide a strong platform as the TOPICAL trial progresses. With growing regulatory, commercial and scientific validation behind the programme, we believe POLB 001 is well positioned to realise its potential as a novel preventative therapy for CRS and to create value through future partnering opportunities.

POLB 001

POLB 001, the Company’s lead strategic programme, delivered key clinical, regulatory and operational milestones during H1 2026, further supporting its development as a potential preventative therapy for cancer immunotherapy-induced CRS.

POLB 001 TOPICAL Clinical Trial

The TOPICAL trial is evaluating POLB 001 in c.30 relapsed/refractory multiple myeloma patients receiving the approved bispecific antibody teclistamab, provided by Johnson & Johnson at no cost to the Company, across six leading specialist cancer centres in the UK. The trial has been designed to generate rapid clinical data given the acute nature of CRS.

During the period, we successfully progressed the programme from regulatory approval into active clinical execution, following site activation and patient recruitment.

Post-period, in July 2026, the Company announced the dosing of the first patient in the TOPICAL clinical trial, marking the commencement of active patient treatment.

Most recently, the review of data from the six-patient safety cohort was completed, resulting in a recommendation that the trial continue as planned, with no changes required to the study protocol. With eight patients now dosed, this positive review represents an important milestone for the TOPICAL trial. Recruitment is continuing across leading UK clinical sites, with further patients expected to be enrolled and additional sites activated. We are pleased with the rate of recruitment to date and encouraged by interest from additional clinical sites in participating in the study.

Intellectual Property

We have continued to strengthen the POLB 001 intellectual property estate. During the period, we secured the first patent grant within our cancer immunotherapy-induced CRS patent family from IP Australia, followed by a patent grant in Canada and a decision to grant from the European Patent Office. We also received a decision to grant our Immunomodulator II patent in South Africa, providing protection for POLB 001 for the prevention of hypercytokinaemia and severe influenza until December 2038.

Post-period end, we received a Notice of Allowance in Israel, indicating a further national patent within the CRS family is set to be granted.

Collectively, these awards enhance the long-term value of POLB 001 and support our ongoing business development and partnering activities.

Regulatory & Partnering

We continued to strengthen the regulatory and commercial positioning of POLB 001 during the period. In May 2026, we announced a positive outcome from a pre-Investigational New Drug ("pre-IND") meeting with the U.S. Food and Drug Administration ("FDA"). The FDA feedback was broadly aligned with key aspects of our envisioned development pathway for POLB 001, including alignment on the proposed primary endpoint for a future Phase 3 clinical trial. This important milestone provides greater clarity regarding the anticipated US development pathway, further de-risks the programme and provides potential partners with a higher degree of certainty regarding the route to market. We believe this feedback reaffirms the attractiveness of POLB 001 and supports our ongoing partnering discussions.

In April 2026, we reported findings from independent US payer research conducted by Acumetis, which engaged payers covering approximately 75 million lives across commercial insurance providers, Medicare and Medicaid. The research reconfirmed the significant unmet need and cost burden associated with cancer immunotherapy-induced CRS, and highlighted POLB 001's potential to reduce hospital costs and enable a meaningful shift in care from specialist centres towards outpatient and community settings. Importantly, payers indicated a willingness to pay at commercially meaningful price points, supporting multi-billion-dollar US peak sales potential and reinforcing the programme's appeal to potential partners.

We remain actively engaged with potential partners in respect of POLB 001 and believe that the recent positive review of the interim safety cohort data could further enhance commercial interest and support ongoing partnering discussions.

Oral GLP-1 Programme

We continue to advance our oral encapsulated GLP-1 programme, which combines AnaBio Technologies' proprietary oral microencapsulation technology with a GLP-1 receptor agonist. The programme is designed to address one of the largest and fastest-growing therapeutic markets globally through a differentiated oral delivery approach.

During the period, we continued preparations for the proof-of-concept clinical study, which is expected to commence in H2 2026. We believe successful clinical validation could create substantial value and unlock multiple opportunities within obesity and broader metabolic disease indications.

Financial

Poolbeg ended the period with a cash balance of £4.8 million (H1 2025: £10.0 million). The loss for the period amounted to £1.9 million (H1 2025: £2.2 million), comprising R&D expenses of £0.9 million (H1 2025: £0.5 million), administrative expenses £1.3 million (H1 2025: £2.0 million), offset by tax rebates and other income & charges of £0.3 million (H1 2025: £0.4 million).

Following the successful £3.5 million (before expenses) fundraising completed in July 2026, we strengthened our balance sheet and extended our cash runway into Q2 2028. The fundraising was supported by both existing and new investors and included a further £250,000 subscription from our Executive Chair, Cathal Friel, demonstrating his continued confidence in Poolbeg's strategy and future prospects. The net proceeds are expected to strengthen Poolbeg's position in ongoing partnering discussions while funding both the POLB 001 TOPICAL trial and the Oral GLP-1 proof-of-concept trial through to completion.

Outlook

Bispecific antibodies are playing an increasingly important role in cancer treatment, and we believe the case for an effective CRS preventative therapy continues to strengthen. POLB 001 has the potential to be the first approved preventative therapy for cancer immunotherapy-induced CRS, reducing healthcare system burden, improving patient outcomes and expanding access to life-saving cancer treatments beyond specialist centres and into outpatient and community settings.

Following the positive review of data from the interim safety cohort, our focus is on continued recruitment in the TOPICAL trial, with further clinical sites having expressed interest in joining. We continue to build a comprehensive evidence package across the programme, designed to support partnering discussions.

Alongside POLB 001, we are advancing preparations for the oral encapsulated GLP-1 proof-of-concept study, expected to commence in H2 2026. We believe the programme offers a differentiated opportunity in one of the largest pharmaceutical markets globally and could create further value and partnering opportunities following successful clinical validation.

With both clinical programmes funded through to completion, multiple anticipated catalysts and an experienced management team with a proven track record, we believe Poolbeg is entering a pivotal phase. We look forward to delivering further progress as we work to unlock the full value of our portfolio for patients and shareholders.

Jeremy Skillington

CEO

Consolidated Statement of Comprehensive Income

For the six months to 30 June 2026

Notes to the Interim Results

General information

Poolbeg Pharma plc (“Poolbeg” or the “Company”) is a public company limited by shares incorporated in England and Wales with company number 13279507. The Company is listed on the AIM market of the London Stock Exchange (ticker: POLB.L, ISIN: GB00BKPG7Z60).

Poolbeg is a clinical-stage biopharmaceutical company with a core focus on transforming the cancer immunotherapy field.

Basis of preparation

The Interim Results of the Company for the six months to 30 June 2026 comprise those of the Company and its subsidiaries (together the “Group”). The Interim Results have been prepared on the going concern basis and under the historical cost convention in accordance with the recognition and measurement requirements of United Kingdom adopted International Accounting Standards (“IFRS”) and their interpretations issued by the International Accounting Standards Board (“IASB”), and in accordance with those parts of the Companies Act 2006 applicable to companies reporting under IFRS. As is permitted by the AIM rules, the Directors have not adopted the requirements of IAS 34 “Interim Financial Reporting” in preparing the financial statements. Accordingly, the financial statements are not in full compliance with IFRS and have neither been audited nor reviewed pursuant to guidance issued by the Auditing Practices Board.

The financial information for the six months to 30 June 2026 and 30 June 2025 is unaudited. The information for the year ended 31 December 2025 has been extracted from the Company's audited accounts on which the auditors issued an unqualified audit opinion. The information presented for that period does not constitute full accounts for that period. The 31 December 2025 audited accounts have been delivered to Companies House.

The financial information is presented in pounds sterling (“£”) which is the functional and presentation currency of the Company. Balances are rounded to the nearest thousand (£’000) except where otherwise indicated.

The Interim Results were approved by the Board of Directors on [28] September 2026.

The accounting policies used in the preparation of the Interim Results are consistent with those used in the Company’s audited financial statements for the year ended 31 December 2025.

Loss per share – basic and diluted

The Group presents basic and diluted loss per share (“LPS”) data for its ordinary shares. Basic LPS is calculated by dividing the loss attributable to ordinary shareholders of the Company by the weighted average number of ordinary shares outstanding during the period. Diluted LPS is determined by adjusting the loss attributable to ordinary shareholders and the weighted average number of ordinary shares outstanding for the effects of all dilutive potential ordinary shares, which comprise warrants and share options granted by the Company.

Issued share capital – ordinary shares of 0.02p each

On 25 June 2025, 194,600,000 ordinary shares of 0.02p were issued at 2.5p per share as part of a £4,865,000 (before expenses) fund raising. In addition, as part of the fundraising arrangements, the Company issued 2,600,000 ordinary shares at the issue price to advisors in lieu of advisory fees.

On 3 February 2026, 7,903,778 ordinary shares of 0.02p were issued at par following the exercise of options by former employees of the Company.

The calculation of loss per share is based on the following:

Under IAS 33.43 “Earnings per Share”, the calculation of loss per share does not assume conversion, exercise, or other issue of potential shares that would have an antidilutive effect on LPS. For the current and comparative periods, the effect of options would be to reduce the loss per share and as such the basic and diluted LPS are the same.

Share options and warrants in issue:

Events after the reporting period

On 13 July 2026, Poolbeg announced the dosing of the first patient in the POLB 001 TOPICAL clinical trial.

On 14 July 2026, Poolbeg announced that it raised £3.5 million (before expenses) pursuant to a placing of 58,333,328 new ordinary shares of 0.02 pence each in the capital of the Company at an issue price of 6 pence per share with certain existing institutional and other investors. In connection with the placing the Company agreed to grant warrants to subscribe for 2,750,000 new ordinary shares at the placing issue price to Oak Securities, the sole bookrunner for the placing.

On 24 September 2026, Poolbeg announced that the ongoing POLB 001 TOPICAL clinical trial will proceed as planned following a positive review of data from the interim safety cohort. The review recommended that the trial continue as planned, with no changes required to the study protocol.

Copy of the interim results

A copy of the Company's Interim Results for the six months to 30 June 2026 is available on the Company's website, www.poolbegpharma.com/investors/documents/