LETTER FROM THE CHAIRMAN AND CEO OF SYNAIRGEN LIMITED
(Incorporated in England and Wales with Registered No. 05233429)
Directors: Mark Parry-Billings (Executive Chairman) | Registered Office: Mailpoint 810, Level F, South Block |
To all Shareholders
26 February 2026
Corporate Update
Dear Shareholders,
Synairgen (the “Company”), a clinical-stage biotechnology company with sole asset SNG001 (inhaled interferon beta), today announces its decision to terminate the ongoing global phase 2 clinical study (referred to as the INVENT study).
The study was designed to evaluate the efficacy and safety of SNG001 in mechanically-ventilated patients infected with a range of respiratory viruses. The first participant was entered into the study in December 2025. However, recruitment has been markedly behind expectations, and despite very active engagement and dialogue with the clinical sites it has been judged that the number of patients projected for a robust study readout is not feasible in a realistic timeframe. There are a number of reasons for this significantly low patient recruitment, not least the very low intensity of the winter viral season; which although prevalent in the community, did not result in a significant number of patients being admitted to intensive care and requiring invasive mechanical ventilation.
A comprehensive review of alternative phase 2 study design options has been carefully conducted by the Synairgen management team, with material input from external clinical, regulatory and drug development experts. However, after careful deliberation, none of these options were considered feasible as they lacked the necessary combined attributes of delivering a material value-inflection generating readout in a realistic timeframe, and all demanded significant additional funding. Tetragon Partners, on behalf of certain funds and managed accounts to which it acts as investment manager (and who own the majority of the Company’s shares), has confirmed that it would not provide further financing to the Company and has recommended that the Company instead focus on returning the maximum available funds to its shareholders.
The Company’s Board of Directors have carefully reviewed various strategic alternatives and have considered the current financing environment, clinical development data outputs and timelines, and the capital requirements of the Company. The Company has determined that it is not in a position to secure the additional significant funding required or a strategic partnership necessary to continue its operations. Accordingly, given that SNG001 is the sole asset of the business, the Board recommends that it is in the best interests of all shareholders that it now advances plans to wind down its operations and returns available cash to shareholders.
The Company therefore plans to begin an orderly wind-down of operations, including meeting its obligations to shareholders, employees, creditors, vendors, and stakeholders in accordance with applicable laws and contractual commitments. Further to the Business Update published on 4 September 2025 and given the current status of the Company, it will not be holding an auction via the Asset Match platform.
Meanwhile, the Company will explore whether there is any opportunity to divest certain intellectual property assets related to SNG001 although there is no guarantee that this will be successful.
The Company will share further details with shareholders regarding the wind-down process in due course, including any shareholder approvals which may be required to approve it.
Joseph Colliver, Chief Executive Officer of Synairgen said: “We are very thankful for all our shareholders who have supported us in the development of SNG001, and for all our clinical and other collaborators and partners, as well as our internal team and colleagues for their dedication and professionalism. This was a very difficult decision, made after thorough consideration of all realistic options available to us and one which the Directors consider is in the best interests of all shareholders as a whole."
Yours sincerely
Mark Parry-Billings | Joseph Colliver |
For further enquiries, please contact:
Synairgen Limited
+ 44 (0)23 8051 2800
info@synairgen.com
For more information about Synairgen, please see www.synairgen.com