- Series A financing co-led by Sofinnova Partners and RA Capital alongside founding investor Oxford Science Enterprises with support from Cancer Research Horizons and the University of Oxford, bringing together a world-class transatlantic syndicate
- Proceeds will fund the Phase 1/2a studies needed to progress ATX-011, a first-in-class therapy for essential thrombocythaemia (ET) and advance additional MPN programmes toward IND submission
- ATX-011 binds a novel target with potential for broad therapeutic benefit irrespective of driver mutation
- Preclinical data for ATX-011 has been selected for oral presentation at the American Society of Hematology (ASH) 2026 Annual Meeting
Oxford, United Kingdom – 5 November 2026 – Alethio Therapeutics ("Alethio"), a biopharmaceutical company developing next-generation therapies for myeloproliferative neoplasms (MPNs), today announces the successful completion of an oversubscribed $90 million (£67 million) Series A financing.
The substantial round was co-led by new investors Sofinnova Partners and RA Capital, alongside founding investor Oxford Science Enterprises, with additional support from Cancer Research Horizons and the University of Oxford. In conjunction with the financing, Graziano Seghezzi, Managing Partner at Sofinnova Partners, and Maxwell DeNies from RA Capital have been appointed to Alethio’s Board of Directors.
The proceeds of the financing will enable Alethio to transition into a clinical-stage company, with capital deployed to advance its lead programme, ATX-011, through completion of Phase 1/2a studies in essential thrombocythaemia (ET), up to Phase 3 readiness, while also progressing additional MPN programmes towards IND submission.
“Too often, a patient's first encounter with ET is a thrombotic event that lands them in the emergency room,” said Dr Rohit Batta, Chief Executive Officer of Alethio Therapeutics. “What follows is typically lifelong treatment with therapies that can cause burdensome side effects and are associated with high rates of resistance. Alethio was founded on a simple conviction - if you can selectively eliminate the cells driving disease, you can redefine what is possible for patients. This financing enables us to turn that conviction into reality.”
Founded as a spin-out from the University of Oxford by Professors Adam Mead and Beth Psaila, two of the world's leading physician-scientists in MPNs, Alethio is building a pipeline of novel therapies informed by their deep expertise in MPN biology. MPNs, including ET, are blood cancers characterised by the uncontrolled production of blood cells and an increased risk of thrombosis, bone marrow scarring (myelofibrosis), and transformation to acute leukaemia.
Current therapies for ET are non-targeted treatments that have been around for decades such as hydroxycarbamide and interferon, that can affect, and disproportionately damage, healthy cells. Alethio is pursuing a different approach, developing targeted therapies designed to selectively eliminate the disease-driving cells that sustain MPNs, to modify the underlying disease features and restore healthy blood counts, reduce thrombotic risk and ultimately improve outcomes for patients.
Preclinical data for ATX-011 has been selected for oral presentation at the American Society of Hematology (ASH) 2026 Annual Meeting, underscoring the strength of Alethio's first-in-class G6B-targeting programme. ATX-011 is designed to normalise platelet counts in patients with ET by selectively enhancing platelet clearance through binding G6B, a protein expressed on platelets and megakaryocytes. Importantly, G6B is also aberrantly expressed on MPN-initiating stem cells, but not healthy stem cells, and on megakaryocytes implicated in the development of bone marrow fibrosis. These findings support the potential of ATX-011 to deliver broad therapeutic benefit across patients with MPNs irrespective of driver mutation. Alethio is advancing ATX-011 through IND-enabling studies and toward clinical development in ET.
"The most transformative companies are built around insights that challenge long-held assumptions in medicine," said Graziano Seghezzi, Managing Partner at Sofinnova Partners. "In MPNs, the field has long accepted that controlling the disease is enough. Alethio challenges that assumption. By targeting the cells that drive the disease, its approach has the potential to move patients beyond symptom management toward true disease modification. All of this is based on an exceptional team and founders with a deep understanding of the disease."
"We were drawn to the strength of the biology underpinning Alethio's approach," said Maxwell DeNies, from RA Capital. "G6B is a highly differentiated target with compelling human data supporting its role in selectively identifying disease-driving cells in MPN. Combined with the extensive patient-derived validation generated by the team, this creates a strong scientific foundation for the programme as it advances toward the clinic."
"Since its formation, Alethio has made incredible progress in translating pioneering University of Oxford science into a focused and ambitious biotechnology company," said Sally Dewhurst, Principal at Oxford Science Enterprises. “The team has built not only a promising lead programme but also the ARTEMIS discovery platform, providing a powerful engine for future pipeline innovation. We are proud to continue supporting the company and are delighted to welcome such an experienced syndicate to help Alethio transition to the next stage of growth; delivering meaningful impact for patients in the clinic."
ENDS
For further information:
Communications Team, Alethio Therapeutics
hello@alethiotx.com
Sandi Greenwood, Frazer Hall, Mark Swallow MEDiSTRAVA
AlethioTx@Medistrava.com
About Alethio Therapeutics
A spin-out from the University of Oxford, Alethio Therapeutics is pioneering the development of targeted therapies with disease-modifying potential for patients with blood cancers, with the aim of helping them live fully, freely and well. The Company is focused on myeloproliferative neoplasms (MPNs), a group of chronic, incurable blood cancers where currently approved treatments are not selectively targeting disease-driving cells.
Alethio’s lead programme, ATX-011, is a first-in-class monoclonal antibody that targets G6B, designed to treat essential thrombocythaemia. G6B is a novel target in MPN that is uniquely expressed on MPN-initiating stem cells, but not healthy stem cells, and also expressed on megakaryocytes and platelets – the cells that drive thrombosis and transformation to myelofibrosis. Alethio is advancing ATX-011 through IND-enabling studies and toward clinical development in ET.
About Essential Thrombocythaemia (ET)
Essential thrombocythaemia (ET) is a myeloproliferative neoplasm characterised by excessive platelet production and an increased risk of thrombosis, bleeding, progression to myelofibrosis and transformation to acute myeloid leukaemia.¹
Current treatments such as hydroxyurea, interferon and anagrelide focus on reducing thrombotic risk and controlling blood counts. While these therapies can control blood counts for some patients, treatment is frequently limited by tolerability challenges, skin toxicity and variable efficacy, highlighting the need for newer therapies that are targeted at the cells that drive pathology, that are better tolerated and more effectively reduce platelet counts.²
ET represents a significant market opportunity. More than 140,000 patients are estimated to be living with the disease in the United States.³ The ET market represents a significant commercial opportunity of over $1 billion annually in the US alone.⁴
References
¹ Tefferi A et al. A Review. JAMA. 2025.
² Tremblay D. Hematology Am Soc Hematol Educ Program. 2023.
³ Company epidemiology analyses and market research.
⁴ Company market model and estimates.
Attachment
