Scarlet Therapeutics Demonstrates In Vivo Survival of Lab-Grown Universal Red Blood Cells Equivalent to Donated Blood

£3.2M Seed Round Closed to Accelerate Platform Development

Bristol, UK, 7 May 2026 — Scarlet Therapeutics ("Scarlet") today announces a landmark preclinical result: its proprietary cell-line derived, universal, lab-grown red blood cells (“RBCs”) have successfully matured and circulated in vivo, achieving a half-life comparable to normal donated red blood cells. Critically, Scarlet's RBCs are designed to be administered regardless of blood type — removing the matching requirement that constrains conventional blood products and allowing a single manufactured product to address a broad patient population.

Building on these results, Scarlet has closed a £3.2 million (approximately USD 4 million) seed financing round to advance the first applications of its RBC platform, initially targeting multiple metabolic diseases, with proceeds supporting in vivo proof-of-concept studies, manufacturing development, and regulatory engagement.

Scarlet’s technology supports three complementary application areas: Treat – long‑acting therapeutic RBCs (tRBCs) engineered to treat a range of serious diseases; Transfuse –universal “off-the-shelf” blood transfusion products free from donor dependency and blood-type compatibility constraints; Enhance – next-generation RBCs designed to improve human performance.

The financing was led by new investor Eos Advisory, with participation from existing investor SCVC, and new investors Oshen Bio (Switzerland & Luxembourg) and Daft Capital (US).

The company also announces three new appointments to the Board of Directors: John Beadle representing Eos Advisory, Didier Cowling from Oshen Bio and Tim Sparey joining as independent Chair of the Board.

Alistair Irvine, CEO of Scarlet Therapeutics, said, “Demonstrating that our lab-grown RBCs can mature and circulate in vivo - with a half-life matching donated blood - is a pivotal validation of what we're building. Our proprietary cell line technology enables scalable, universal RBC manufacturing and opens the door to a new class of durable therapeutics and transfusion products. This financing puts us in a strong position to select our lead therapeutic candidate and move towards the clinic.”

Harry Destecroix, Managing Partner of SCVC, stated, “These results mark a major milestone for Scarlet - moving from concept to in vivo validation is a genuine inflection point. Scarlet has the science and the ambition to become a defining company in engineered red blood cells, and we're proud to continue backing that vision.”

Anne Muir, Director of Portfolio at Eos, said, “Scarlet Therapeutics is developing technology that could genuinely change the way we treat a range of serious diseases - this is exactly the kind of first-in-class science, with the potential to transform human health, that we back at Eos. The idea of a universal, scalable red blood cell platform - free from donor dependence and compatibility constraints - is remarkable, and Alistair and his team have the science and vision to make it a reality. We are proud to have led this round and look forward to supporting the next phase of Scarlet’s journey.”