Cytospire Raises £61M to Advance Next-Gen Gamma Delta T Cell Cancer Therapy

LONDON, UK – May 05, 2026 – In a significant endorsement of a new frontier in cancer immunotherapy, UK-based biotech firm Cytospire Therapeutics has announced the closing of an oversubscribed £61 million ($83 million) Series A financing round. The capital infusion, one of the larger for a UK biotech at this stage, is set to propel the company’s first-in-class pipeline of pan-gamma delta T cell engagers into clinical trials, offering new hope for treating solid and liquid tumors.

The financing underscores a powerful wave of investor confidence in Cytospire’s novel approach, which aims to overcome the efficacy and safety hurdles that have limited conventional T cell-based cancer treatments. The company’s lead program, CYT X300, is now poised to advance toward human trials for treating EGFR-positive solid tumors, including colorectal, head and neck, and non-small cell lung cancers.

A Syndicate of Conviction

The funding round was led by 4BIO Capital, a venture firm specializing in advanced therapies, and saw participation from a formidable syndicate of new and existing investors. The high-profile group of new backers includes Servier Ventures, Sound Bioventures, the British Business Bank, and Criteria Bio Ventures. Their commitment signals a strong belief in the potential of Cytospire's technology to disrupt the immune-oncology landscape. Existing investors Abingworth and LifeArc Ventures also reinforced their support, demonstrating continued faith in the company's trajectory since its inception.

Notably, this marks the first-ever investment from Servier Ventures, the newly minted corporate venture arm of the global pharmaceutical group Servier. This inaugural move is a strategic bet on Cytospire's science and a powerful validation of its platform's potential to deliver breakthrough therapies.

Owen Smith, Partner at 4BIO Capital and a Cytospire Board Member, commented on the significance of the investment. “Cancer immunotherapy has provided a step-change in treatment for many types of cancer over the past decade, but we need to do more,” he stated in the press release. “We are proud to have led the Series A alongside this strong investor syndicate. It is exciting to see the company advance CYT X300 and its pioneering portfolio of cancer therapies into the clinic to improve outcomes for cancer patients.”

The participation of the British Business Bank, through its Life Sciences Investment Programme, also highlights the strategic importance of Cytospire to the UK's burgeoning life sciences ecosystem, aiming to foster growth-stage, R&D-intensive companies with global potential.

Beyond Conventional Immunotherapy: The Science of Gamma Delta T Cells

At the heart of the investor excitement is Cytospire's innovative technology platform. The company is developing multispecific immune cell engager antibodies designed to harness a unique and potent branch of the immune system: gamma delta T cells.

Most current T cell engager therapies, a class of drugs that act as a bridge to connect cancer cells with immune cells, target conventional alpha-beta T cells via the CD3 receptor. While this approach has seen success, it is often hampered by significant side effects, including cytokine release syndrome, and can be ineffective against tumors that have evolved to hide from the immune system.

Cytospire's platform circumvents these issues by engaging gamma delta T cells, a distinct T cell population with unique biological advantages. These cells are abundant in tissues and act as a first line of defense against cellular stress and malignancy. Crucially, they can recognize and kill cancer cells independently of the Human Leukocyte Antigen (HLA) system, a cellular presentation mechanism that tumors frequently downregulate to evade detection by conventional T cells. This makes Cytospire's approach potentially effective against a broader range of tumors and less susceptible to common resistance mechanisms.

“Immune cell engagers are an important type of cancer immunotherapy, but we know that there are significant limitations from both an efficacy and safety perspective with conventional CD3 T cell engagers,” said Natalie Mount, Chief Executive Officer of Cytospire Therapeutics. “We are building on the growing body of translational and clinical data showing gamma delta T cells are critical components of the anti-cancer immune response, with biology ideally suited to novel cell engagers.”

Cytospire's “pan-gamma delta” strategy is engineered to activate all subtypes of these cells, including both tissue-resident and blood-circulating populations, to mount a broader and more comprehensive anti-tumor attack.

Advancing CYT X300 to Tackle Solid Tumors

The newly secured funds will be channeled directly into advancing Cytospire's pipeline, with a primary focus on its lead candidate, CYT X300. This program is currently undergoing IND-enabling preclinical studies and GMP manufacturing in preparation for its first-in-human clinical trial.

CYT X300 is designed to target EGFR-positive solid tumors, which represent a significant area of unmet medical need. Epidermal Growth Factor Receptor (EGFR) is a well-validated cancer antigen found on the surface of several common and aggressive cancers, including many cases of colorectal, head and neck, and non-small cell lung cancer. While targeted therapies against EGFR exist, patients often develop resistance, creating a continuous need for novel therapeutic strategies.

By leveraging the unique biology of gamma delta T cells, Cytospire hopes to provide a safer and more durable treatment option for these patients. The company's technology may allow for effective targeting of EGFR without the severe toxicities that have limited the development of some CD3-based T cell engagers against this same target.

Bali Muralidhar, Global Head of Life Sciences at founding investor Abingworth, emphasized the novelty of the approach. “As the founding investor in Cytospire, we are strong believers in the potential of gamma delta T cell-based therapies to change the treatment paradigm in multiple cancer indications,” he noted. “There is a need for novel strategies in the field of immune cell engagers, and we believe that Cytospire is well positioned at the forefront of this exciting space”.

Strengthening Leadership for Clinical Ascent

To guide its transition from a preclinical-stage company to a clinical-stage one, Cytospire has also fortified its Board of Directors. The new appointments bring a wealth of financial, strategic, and developmental experience. Joining the board are Alexis Vandier, Global Head of Servier Ventures; Carmine Circelli, Investment Director at the British Business Bank; and Anna Gran, Principal at Sound Bioventures.

These additions provide Cytospire with direct access to the expertise of its key new investors, ensuring strategic alignment and robust governance as the company navigates the complexities of clinical development, regulatory submissions, and future corporate growth. This fusion of groundbreaking science, substantial capital, and experienced leadership positions Cytospire Therapeutics to make a meaningful impact in the ongoing fight against cancer.