4basebio and TriLink BioTechnologies Partner to Advance Leading Pharmaceutical Company’s Phase I Cell Therapy Program

• Collaboration extends existing relationship with the Tier 1 pharmaceutical customer into cell therapy programs
• End-to-end supply chain combines 4basebio's proprietary opDNA® enzymatic DNA starting material with TriLink's industry-leading GMP mRNA manufacturing capabilities and proprietary CleanCap® co-transcriptional capping technology

CAMBRIDGE, UK – 28 September, 2026 – 4basebio PLC (AIM: 4BB), a specialist in enzymatically-produced DNA for new genetic medicines, announces they will supply clinical-grade opDNA® starting material for a multi-national pharmaceutical innovator’s (“the Client”) latest cell therapy program.

Under the agreement, 4basebio will supply synthetic DNA to be used as a critical material for the Client’s upcoming Phase I clinical trial. TriLink BioTechnologies (TriLink), part of Maravai LifeSciences has been selected as the contract development and manufacturing organisation (CDMO) to manufacture the mRNA drug substance, applying its proprietary CleanCap® co-transcriptional capping technology. The agreement reflects 4basebio’s commitment and mission to provide a safer, cost-effective replacement for plasmid DNA in the development of genetic medicines.

Christine Wolosin, Chief Commercial Officer at 4basebio, added: “We're excited to continue our relationship with this leading pharmaceutical innovator as they advance new molecules into the clinic. This collaboration is a testament to the quality and consistency of our opDNA® platform, and to the strength of the partnerships we've built across the CDMO ecosystem. Working alongside TriLink – a world-class mRNA manufacturer - allows us to plug our starting material seamlessly into established manufacturing workflows, giving customers a faster, lower-risk path to the clinic without having to change how they already work with their chosen manufacturing partners.”

Chad Decker, Senior Vice President, Global Sales at TriLink commented: “TriLink is proud to be the CDMO of choice for this important cell therapy program. With our CleanCap® technology paired with 4basebio's high-purity opDNA® as starting material, we can offer this program with exceptional consistency from DNA template through finished drug substance. This is exactly the kind of end-to-end, quality-forward collaboration that accelerates programs from IND to first patient. We look forward to applying our mRNA manufacturing expertise to help bring this therapy closer to patients.”

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.

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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.

About TriLink BioTechnologies

TriLink BioTechnologies, part of Maravai LifeSciences, is a global leader in nucleic acid technologies and manufacturing solutions for RNA therapeutics, vaccines, gene editing, and diagnostics. The company's portfolio includes modified nucleotides, mRNA products, proprietary technologies such as CleanCap® capping analogs and ModTail® technology, and a growing portfolio of high-performance enzymes marketed under the Alphazyme brand. Supported by robust GMP manufacturing capabilities, TriLink enables customers from early-stage research through commercial production.

For more information, visit trilinkbiotech.com

About Maravai LifeSciences

Maravai LifeSciences is a leading life sciences company providing critical products to enable the development of drug therapies, diagnostics, and novel vaccines and to support research on human diseases. Maravai’s companies are leaders in providing products and services in the fields of nucleic acid synthesis and biologics safety testing to many of the world’s leading biopharmaceutical, vaccine, diagnostics, and cell and gene therapies companies.

For more information, visit Maravai.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.