Cytospire Therapeutics
London oncology biotech; first-in-class T cell engager drug for solid tumours; £61m Series A May 2026.
Last refreshed: 13 May 2026 · Appears in 1 active topic
What cancer drug is Cytospire taking to clinic with its £61m Series A?
Timeline for Cytospire Therapeutics
Mentioned in: IMU raises £40m to read blood
UK Startups and InnovationMentioned in: Lansdowne hits €128.9m on BBB-anchored fund
UK Startups and InnovationClosed oversubscribed £61m Series A to advance CYT X300 pan-gamma delta T cell engager toward clinical trials
UK Startups and Innovation: Cytospire's £61m oncology Series A oversubscribed- What is Cytospire Therapeutics developing?
- Cytospire is developing CYT X300, a first-in-class pan-gamma delta T cell engager targeting EGFR-positive solid tumours such as lung and colorectal cancer.Source: Cytospire Therapeutics
- How much did Cytospire Therapeutics raise in its Series A?
- Cytospire raised £61m in an oversubscribed Series A on 5 May 2026, led by 4BIO Capital with BBB contributing £12m as co-investor.Source: Lowdown
- What is a gamma delta T cell engager and why does it matter for cancer?
- A gamma delta T cell engager is a drug that recruits a rare subset of T cells — positioned between innate and adaptive immunity — to attack tumour cells, potentially triggering a broader immune response than conventional alpha-beta T cell therapies.
Background
Cytospire Therapeutics closed an oversubscribed £61m Series A on 5 May 2026, led by 4BIO Capital with BBB contributing £12m as co-investor alongside Servier Ventures, Abingworth, LifeArc Ventures, Sound Bioventures, and Medical Incubator Japan. The company, incorporated in February 2023, is developing CYT X300, described as a first-in-class pan-gamma delta T cell engager targeting EGFR-positive solid tumours — a category that includes lung, colorectal, and head-and-neck cancers.
Gamma delta T cells sit at the intersection of innate and adaptive immunity; most oncology immunotherapies target alpha-beta T cells or NK cells. CYT X300's pan-gamma delta mechanism is designed to activate a broader immune response against tumour cells expressing EGFR, a receptor over-expressed in many common solid cancers. The oversubscribed round at Series A stage — within three years of incorporation — signals strong investor conviction in the mechanism.
Cytospire is among the earliest cohort of London biotechs to leverage the BBB's direct mandate activated in April 2026. The £12m BBB stake alongside a Japanese medical incubator as a co-investor shows cross-border interest in the platform, and the oversubscription on a £61m Series A is unusually strong for a company still in early clinical development.