Sofinnova and RA Capital co-lead $90m Series A for Oxford spin-out Alethio

Alethio Therapeutics, a biotech based in Abingdon, Oxfordshire, said on 5 November 2026 that it had raised $90 million in a Series A round co-led by Sofinnova Partners and RA Capital Management¹. Cancer Research Horizons, Oxford Science Enterprises and the University of Oxford also took part¹.

What the money is for

Alethio spun out of University of Oxford research and was co-founded by two physicians and professors there, Adam Mead and Beth Psaila¹. The company targets myeloproliferative neoplasms, slow-progressing blood cancers in which the body overproduces blood cells, a group that includes primary myelofibrosis, essential thrombocythemia and polycythemia vera¹.

Its lead asset, ATX-011, is a monoclonal antibody that binds G6b, a receptor on platelets and some bone marrow cells¹. Alethio's case rests on G6b appearing only on the cells that drive these diseases or scar the bone marrow, which it argues could give a precise effect and work whichever disease-causing mutation a patient carries¹. Chief executive Rohit Batta said preclinical studies showed the antibody behaves well as a medicine¹. A second candidate, an antibody-drug conjugate for myelofibrosis, is in development¹.

What it means for the market

The round puts $90 million behind a preclinical UK university spin-out before any human data exist, and it brings two specialist investors in alongside a cancer charity's commercial arm and Oxford's own backers¹. For corporate development teams, the relevant competitors are already large: Incyte, maker of Jakafi, along with Merck & Co. and Novartis are active in the field, and Takeda's Mimrylo was recently approved for polycythemia vera¹.

Alethio's commercial pitch centres on essential thrombocythemia. Graziano Seghezzi, managing partner at Sofinnova Partners, argued that this focus could give the drug wider "reach" than approved treatments for other myeloproliferative neoplasms¹. Alethio puts the number of US patients with essential thrombocythemia at an estimated 150,000, which it says exceeds the combined totals for polycythemia vera and primary myelofibrosis¹. Batta said existing options, from blood withdrawals and hydroxyurea to interferon and JAK inhibitors, still fail most patients¹.

Caveats

The evidence so far is preclinical, and the patient estimate and the claimed advantage over rival drugs come from the company and its investor rather than from trial data¹. The valuation and the split between the two lead investors were not disclosed in the report¹.

ATX-011 is expected to begin clinical testing in the first half of 2028¹.