Lilly adds potential first-in-class Type II JAK2 inhibitor to haematology portfolio

Eli Lilly has confirmed a second major acquisition this month, now agreeing to pay US-based biopharmaceutical company Ajax Therapeutics up to $2.3 billion, for its potential first-in-class Type II JAK2 inhibitor.

Ajax’s oral candidate, AJ1-11095, is currently being evaluated in a Phase I clinical trial, AJX-101, in those with myelofibrosis previously treated with a Type I JAK2 inhibitor. While these JAK2 inhibitors provide clinical relief, many patients often discontinue treatment due to a lack of durable benefit or loss of response.

However, AJ1-11095 could deliver deeper and more durable disease control than approved therapies for myeloproliferative neoplasms (MPNs) such as myelofibrosis and polycythaemia vera, the companies noted.

AJ1-11095 has potential to deliver deeper and more durable efficacy than available treatments with a tolerability profile that would allow for patients to remain on therapy longer and be used across both the first- and second-line settings”

Jacob Van Naarden, Executive Vice President and President of Lilly Oncology and Head of Corporate Business Development remarked that AJ1-11095 has potential to deliver “deeper and more durable efficacy than available treatments with a tolerability profile that would allow for patients to remain on therapy longer and be used across both the first- and second-line settings.

“We look forward to the presentation of clinical proof-of-concept data later in 2026, rapidly advancing AJ1-11095 into registrational clinical trials, and using our expertise in blood cancer to hopefully deliver another important new medicine to patients and haematologists.”

Eli Lilly’s acqusition of Ajax is subject to customary closing conditions.

In March, Sanofi also gained access to a first-in-class JAK inhibitor in haematology. The $1.5 billion development and commercialisation deal is with Sino Biopharmaceuticals.

Earlier this year, Gilead furthered ambitions in blood cancer by adding a CAR T-cell therapy candidate to its portfolio by acquiring biotech Arcellx for $7.8 billion. Similar to Ajax’s lead asset, AJ1-11095, Arcellx’s candidate anitocabtagene autoleucel (anito-cel) has demonstrated clinical evidence that it can provide deep and durable responses in patients.