Alethio Therapeutics, an Oxford spinout focused on rare blood disorders, raised an oversubscribed $90 million Series A to advance ATX-011 into Phase I/IIa studies for essential thrombocythemia. The lead asset is a monoclonal antibody targeting G6B to lower platelet counts by boosting platelet clearance, with the company also positioning G6B expression on MPN-initiating stem cells as a potential basis for broader disease impact. The financing is intended to support IND-enabling work and first-in-patient data, with Alethio stating there is precedent for moving from first-in-human into Phase III in ET. Investors include Sofinnova Partners and RA Capital, alongside participation from Oxford Science Enterprises. For clinicians and developers, the round signals continued interest in targeted, biology-driven approaches for ET—especially given the limitations of current therapies like hydroxyurea and the unmet need for mutation-agnostic options.