Eli Lilly to acquire Ajax Therapeutics for up to $2.3B in blood cancer bet
What’s the deal? Eli LillyDealroom has a profile for this one. Try Dealroom → will acquire Ajax Therapeutics for up to $2.3B in cash. The price includes an undisclosed upfront payment and milestone payments tied to clinical and regulatory targets. The deal was announced on 27 April 2026 and is subject to Hart-Scott-Rodino antitrust approval.
Ajax’s lead asset is AJ1-11095, a first-in-class Type II JAK2 inhibitor currently in a Phase 1 trial for patients with myelofibrosis who have previously been treated with a Type I JAK2 inhibitor. The drug has FDA orphan drug designation. Proof-of-concept data is expected later in 2026.
Why now? Current JAK2 inhibitors for myeloproliferative neoplasms (MPNs) — including IncyteDealroom has a profile for this one. Try Dealroom →’s Jakafi — bind the active (Type I) conformation of JAK2. They provide symptomatic relief but many patients discontinue treatment because the drugs stop working. AJ1-11095 binds the inactive (Type II) conformation, which Ajax says could deliver deeper, more durable efficacy and offer a treatment option for patients resistant to existing therapies.
Ajax was founded in 2019 by CEO Martin VogelbaumDealroom has a profile for this one. Try Dealroom → and scientific founder Ross LevineDealroom has a profile for this one. Try Dealroom →, chief scientific officer at Memorial Sloan Kettering Cancer Center, with founding partner SchrödingerDealroom has a profile for this one. Try Dealroom → providing computational drug discovery capabilities. Lilly was a founding strategic investor and participated in Ajax’s $95M Series C in 2024.
What could go wrong? AJ1-11095 is Phase 1 — the earliest stage of clinical testing. Lilly itself previously developed a JAK2 inhibitor that failed. No proof-of-concept data has been presented yet, meaning the $2.3B headline rests on preclinical promise and an untested mechanism in humans.
The Type II binding approach is scientifically grounded but unproven at scale. Myelofibrosis is a rare disease with a small patient population, which limits the commercial ceiling even if the drug works. And the undisclosed upfront/milestone split means the true cost to Lilly — and the true windfall to Ajax shareholders — depends entirely on data that has not yet been generated.
The signal: This is Lilly’s third oncology acquisition in three weeks, following CrossBridge BioDealroom has a profile for this one. Try Dealroom → and Kelonia Therapeutics. Since the start of 2026, the pharma has also acquired Centessa Pharmaceuticals, Orna Therapeutics, Ventyx Biosciences, and Scorpion Therapeutics. All deals include significant contingent milestone payments.
Flush with obesity drug revenue, Lilly is executing what RBC Capital Markets calls a “land grab M&A playbook” — acquiring differentiated assets before pivotal data makes them more expensive. 2026 is on track to become one of biotech’s most active M&A years ever, according to Stifel.
Sources:
Reuters
Bloomberg
Wall Street Journal
BioSpace
BioPharma Dive
Ajax Therapeutics
Eli Lilly Investor Relations
Image credit:
Ajax Therapeutics
J.V.
