Alethio raises $90M to take an Oxford MPN antibody into the clinic

Myeloproliferative neoplasms are mostly managed with blood draws, hydroxyurea, interferon and JAK inhibitors. Alethio Therapeutics wants to clear out the cells behind them instead, and on 5 November it closed an oversubscribed $90 million (£67 million) Series A to try.

Sofinnova Partners and RA Capital co-led the round, both as new investors. Oxford Science Enterprises, the founding investor, took part, with support from Cancer Research Horizons and the University of Oxford.

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The science

Alethio was spun out of University of Oxford research and is based in Abingdon, Oxfordshire. Its founders are physician-scientists Professors Adam Mead and Beth Psaila, and it is run by chief executive Dr Rohit Batta.

The lead programme, ATX-011, is an antibody against G6B, a protein found on platelets, megakaryocytes and the stem cells that initiate MPNs. BioPharma Dive reports that the company thinks it could work whichever disease-driving mutation a patient carries. A second candidate, an antibody-drug conjugate for myelofibrosis, is also in development.

"The ultimate aim for ATX-011 is to allow patients to go and live their daily lives," Dr Rohit Batta, chief executive officer, Alethio Therapeutics

Where the money goes

ATX-011 is currently in IND-enabling studies. The round is meant to turn Alethio into a clinical-stage company, run Phase 1/2a studies of ATX-011 in essential thrombocythaemia through to Phase 3 readiness, and move other MPN programmes towards IND submission. BioPharma Dive says the antibody is expected to enter clinical testing in the first half of 2028. Before then, preclinical ATX-011 data has been picked for an oral presentation at the ASH 2026 Annual Meeting.

Graziano Seghezzi, managing partner at Sofinnova, and Maxwell DeNies of RA Capital join the board.

The bigger picture

More than 140,000 people in the US are estimated to be living with essential thrombocythaemia alone, according to Alethio. The field already includes Incyte, maker of Jakafi, plus Merck & Co. and Novartis, so a new entrant needs a clear point of difference. Alethio's is a target that sits on the disease-initiating cells.

Our read: this is a strong Series A for a UK academic spinout, with both lead investors taking board seats. The two years before first dosing are when a company like this builds the team that will run its first trial.

What it means for hiring

Moving from IND-enabling work to a US filing and a Phase 1/2a study usually means a first head of clinical development, a regulatory affairs lead with IND experience and CMC leadership for an antibody programme.
Haematology-oncology clinical leaders who know MPN trial design and endpoints are a small pool. In our view, UK biotechs running US-facing programmes will compete for them with larger companies already in the field.
Spinouts at this stage often add an experienced CMO or COO alongside a founding team. We'd expect the senior hiring here to lean towards people who have taken an antibody from IND into the clinic.

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