Director Appointment

4basebio PLC

("4basebio" or the "Company")

Director Appointment

CAMBRIDGE, UK – 08 July 2026   –   4basebio PLC (AIM: 4BB), a company pioneering an enzymatically-produced DNA technology serving the next generation genetic medicines markets, is pleased to announce the apppointent of Mr. Cornel Chiriac as Non-executive Director of the Company with immediate effect.

Mr. Chiriac currently serves as an investment director at M&G Investments’ Crossover Fund, and brings 25 years of experience in investing and portfolio and operational management, with 10 years focused on deep tech and science venture capital.

Earlier in his career, Mr. Chiriac was a founding partner of 2050 Capital, a London-based deep tech and science venture capital firm, through which he holds a number of portfolio directorships. Prior to that, he built and scaled two ventures in the USA to multi-million-dollar exits, having begun his career as a strategy and deal consultant with L.E.K. Consulting. He holds an MBA from the University of Chicago Booth School of Business.

Pursuant to Rule 17 and Schedule 2(g) of the AIM Rules for Companies, the following information is disclosed in respect of Mr. Corneliu (“ Cornel ”) Chiriac (aged 49):

Current Directorships	Previous Directorships held in the past five years
2050 Capital Limited	Elemente LLC
Autonomous Manufacturing Ltd	International Kilobar Association Ltd
Bit Bio Limited	The Naked Pharmacy Ltd
Blue Elm Limited
Hadean Supercomputing Ltd
OSCPS Motion Sensing Inc
TriEye Limited

Mr. Chiriac holds no Ordinary Shares, and no options or warrants over Ordinary Shares. There is no further information regarding Mr. Chiriac that is required to be disclosed under the AIM Rules.

Dr. Amy Walker, CEO of the Company said: “ 'I am delighted to welcome Cornel to the 4basebio Board following his involvement in the Company for the last two years representing M&G. His strategic perspective, thoughtful approach and strong understanding of scaling innovative technology businesses will be a valuable addition as we continue to grow our commercial business and execute our long-term strategy. I look forward to working with him as we build on our momentum and create further value for shareholders .”

This announcement contains inside information for the purposes of Article 7 of EU Regulation 596/2014 as amended by regulation 11 of the Market Abuse (Amendment) (EU Exit) Regulations 2019/310.

For further enquiries, please contact:

4basebio PLC	[phone]
Dr Amy Walker, CEO
Cairn Financial Advisers LLP (Nominated Adviser)	[phone]
Jo Turner / Sandy Jamieson / Ed Downes
Cavendish Capital Markets Limited (Joint Broker)	[phone]
Geoff Nash / Nigel Birks
RBC Capital Markets (Joint Broker)	[phone]
Kathryn Deegan / Matthew Coakes
ICR Healthcare (Media and Investor Relations)	[phone]
Mary-Jane Elliott / Jessica Hodgson

About 4basebio

4basebio (AIM: 4BB) is a Cambridge-based biotechnology company pioneering the use of synthetic DNA to enable next-generation therapeutics and vaccines. Through its proprietary enzymatic DNA synthesis platform, 4basebio produces GMP-grade synthetic DNA and mRNA with superior speed, purity, and scalability, overcoming the limitations of plasmid-based systems. The company offers application-specific DNA constructs tailored to the diverse needs of gene therapies, genome editing, mRNA production, and DNA vaccines, helping partners accelerate proof-of-concept studies and reach clinical milestones more efficiently while maintaining the highest standards of safety and quality.

For more information, visit 4basebio.com .

Forward-looking statements

This announcement may contain certain statements about the future outlook for 4basebio.   Although the directors believe their expectations are based on reasonable assumptions, any statements about future outlook may be influenced by factors that could cause actual outcomes and results to be materially different.

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