Alistair Irvine
Chief Executive Officer, Board Member
Alistair Irvine, PhD, co-founded Scarlet in August 2022. He is an experienced biotech and medtech executive who has worked in the industry for >28 years and has broad international executive and R&D experience. Previous to Scarlet, he was Chief Business Officer at Kuros Biosciences AG, a public Swiss biotech company, and he has also held senior management roles at Innovata plc, ML Laboratories plc, and Cobra Therapeutics Ltd. Dr. Irvine holds a PhD in Molecular Biology from the University of Sheffield and a BSc in Biochemistry from the University of Edinburgh.
Professor Ash Toye
Chief Scientific Officer, Board Member
Ashley Toye, PhD, co-founded Scarlet Therapeutics in 2022 as a spin out from his extensive work as Professor of Cell Biology at the School of Biochemistry at University of Bristol. He is the Director of the National Institute for Health Research (NIHR) Blood and Transplant Research Unit in Red Cell Products at the University of Bristol and is responsible for delivery of the RESTORE clinical assessment of laboratory grown blood. Prof Toye’s lab is focused on the culture of blood cells, in particular the manipulation of erythropoiesis in health and disease. He uses synthetic biology approaches with the goal of generating novel therapeutics from in vitro produced reticulocytes. Prof Toye holds a PhD in Biochemistry from the University of Bristol.
Professor Jan Frayne
Chief Technology Officer
Jan Frayne, PhD, co-founded Scarlet in 2022. She is a Professor of Molecular Cell Biology in the School of Biochemistry at the University of Bristol. Her main research focus for the past few decades has been the molecular analysis of erythropoiesis in vitro, and the development of proteomic approaches to study this process. She studies the development of red blood cells from stem cell sources including adult peripheral blood, umbilical cord blood and iPSCs. Her lab is also well-known for generating novel erythroid cell lines to model healthy and diseased erythroid differentiation. Prof Frayne holds a PhD in Immunology from the University of Bristol.
Marjolein Meinders
Group Leader
Marjolein Meinders, PhD, co-founded Scarlet Therapeutics in 2022. Formerly, she worked as a senior post-doctoral researcher in Prof. Toye’s laboratory, dedicating 15 years to study blood cell production, with the emphasis on red blood cells and megakaryocytes. She is specialised in developing culturing condition for blood cells and manipulation methods to express proteins, with a focus on medicinal applications. At Scarlet, she leads the Research and Development team, leveraging her expertise to oversee innovative projects. She has a masters degree in immunology and a PhD in megakaryopoiesis which she completed at Sanquin, the Dutch blood bank.
Tim Sparey
Chairman
Dr. Tim Sparey is a seasoned executive, entrepreneur, and biotech strategist with more than 30 years of leadership experience in the pharmaceutical and life sciences industry. He has built an impactful career at the intersection of drug discovery, business development and corporate growth, spanning large pharma, emerging biotech and advisory roles. An accomplished medicinal chemist by training, Tim began his career in early-stage research and development, spending 12 years advancing chemical biology programmes at Merck & Co before transitioning to global Business Development & Licensing for 3 years. Tim has held senior roles in multiple biotech companies, leading transformative growth phases, built high-performing teams and driven strategic collaborations and transactions valued at over US$7 billion across M&A, licensing, partnerships and fundraising. He is an innovator with more than 40 patents and scientific publications and a recognised contributor to advances in drug discovery.
Harry Destecroix MBE
Board Member
Harry Destecroix, PhD, is the founder of the Science Creates ecosystem and Managing Partner of SCVC, where he supports the growth, investment and commercialisation of Deep Tech companies UK-wide. He founded his first company, Ziylo, in 2014 during his chemistry PhD at the University of Bristol and as CEO led the spinout to acquisition in 2018 in a deal worth up to $800m. In 2017, Harry built Bristol’s first Deep Tech incubator through Science Creates after identifying the need for specialised lab space for startups in the city. Harry’s work has been recognised multiple times, winning the 2023 RSC award for Chemistry World Entrepreneur of the Year and earning an MBE in the King’s 2025 New Year Honours List for his services to science.
John Beadle
Board Member
Dr. John Beadle is an experienced biotechnology entrepreneur, physician, and senior executive with more than 25 years of global leadership across immunotherapy, gene therapy and cell therapy. He was the founding CEO of PsiOxus Therapeutics, where he advanced multiple clinical programs and secured major strategic partnerships. He also co-founded PowderMed, a DNA vaccine company where he was Chief Medical Officer and Board Director. At PowderMed, his team delivered the world’s first clinical efficacy signal for a nucleotide-based vaccine, which then supported the company’s trade sale to Pfizer. Earlier in his career, Dr Beadle held senior roles in R&D at GSK.
Didier Cowling
Board Member
Didier Cowling has worked in and around the life sciences industry for over 30 years. He has been a founder, CEO, Chairman and Board Member of several medtech and biotech companies. This has included developing a number of products from the lab through to market launch, raising several hundred millions of investment, several mergers and acquisitions, IPOs and significant collaborations with healthcare companies. Didier is a graduate of Cambridge University specialising in Chemistry and Biochemistry. He also trained as a pharma analyst in the financial services industry in the City of London. Didier is passionate about science and technology related to human health and translating new developments into successful business ventures.
Our partners
Our partners who have helped Scarlet to get where we are today:
