CYT X300
Cytospire's first-in-class pan-gamma delta T cell engager targeting solid tumours in Phase I.
Last refreshed: 13 May 2026 · Appears in 1 active topic
Timeline for CYT X300
Cytospire's £61m oncology Series A oversubscribed
UK Startups and Innovation- What is CYT X300 and what does it treat?
- CYT X300 is Cytospire's first-in-class pan-gamma delta T cell engager targeting solid tumours, entering Phase I trials after a £61m Series A in May 2026.Source: Lowdown uk-startups-and-innovation U#4
- What is a gamma delta T cell engager in cancer treatment?
- A gamma delta T cell engager recruits gamma delta T cells to kill tumour cells. Unlike CAR-T, gamma delta approaches are not HLA-restricted, making them applicable to a broader patient population including solid tumours where CAR-T has struggled.Source: Lowdown uk-startups-and-innovation U#4
- Why is Cytospire's cancer drug considered first-in-class?
- CYT X300 is described as first-in-class because no approved pan-gamma delta T cell engager existed at the time of Cytospire's Series A fundraise.Source: Lowdown uk-startups-and-innovation U#4
Background
CYT X300 is Cytospire's lead clinical asset, described as a first-in-class pan-gamma delta T cell engager for the treatment of solid tumours. The programme was the clinical centrepiece of Cytospire's £61m Series A in May 2026, drawing investors including Abingworth, Servier Ventures, LifeArc Ventures, Sound Bioventures, and Medical Incubator Japan.
Gamma delta T cells are a subset of T cells that recognise tumour-associated antigens through both innate and adaptive immune mechanisms. Unlike conventional alpha-beta T cell therapies (such as CAR-T), gamma delta approaches are not restricted by HLA type, making them potentially applicable across a broader patient population and for solid tumours where CAR-T has historically struggled. A 'pan' gamma delta engager means CYT X300 aims to recruit multiple gamma delta T cell subtypes simultaneously, increasing the breadth of tumour cell killing. The 'first-in-class' designation reflects that no approved pan-gamma delta engager existed at the time of Cytospire's Series A. The round will fund Phase I clinical trials for CYT X300.