Scarlet Therapeutics, a Bristol-based engineered red blood cell startup, has raised £3.2 million in a seed financing round led by Eos Advisory, with participation from SCVC, Oshen Bio and Daft Capital. Scarlet Therapeutics develops therapeutic red blood cells to treat metabolic diseases and address shortages in rare blood supplies.
Founded in 2022 by professors Jan Frayne and Ashley Toye, Scarlet Therapeutics initially focused on culturing red blood cells to address ongoing rare blood shortages in the UK and abroad before applying synthetic biology approaches to develop engineered therapeutic red blood cells. Proprietary cell line technology is designed to enable scalable, universal red blood cell manufacturing for therapeutic and transfusion products.
Proceeds from the financing round will be used to advance the first applications of Scarlet Therapeutics’ red blood cell platform, initially targeting multiple metabolic diseases. Funding will support in vivo proof-of-concept studies, manufacturing development and regulatory engagement.
Demonstrating that lab-grown red blood cells can mature and circulate in vivo with a half-life matching donated blood was described by Scarlet Therapeutics as validation of its platform technology. Scarlet Therapeutics has also appointed John Beadle representing Eos Advisory, Didier Cowling from Oshen Bio, and Tim Sparey as independent chair to its board.
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.
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.
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.
