Lilly is buying a company a week. That is not hyperbole. Since February, Lilly has announced five acquisitions totaling approximately $19.8 billion in committed capital: Orna Therapeutics ($2.4 billion, in vivo CAR-T, February), Centessa Pharmaceuticals ($7.8 billion, narcolepsy, March), Kelonia Therapeutics (up to $7 billion, in vivo CAR-T, April 20), CrossBridge Bio (up to $300 million, dual-payload ADC, April 22), and now Ajax Therapeutics (up to $2.3 billion, blood cancer, April 27). Fierce Biotech called it “Lilly’s run of near-weekly acquisitions” and noted the pace “shows no sign of letting up.” The Ajax deal adds a first-in-class Type II JAK2 inhibitor for myelofibrosis to Lilly’s expanding oncology pipeline—a compound designed to overcome the resistance that limits every currently approved JAK2 therapy. Meanwhile, Regeneron signed an MFN deal with the White House on April 23, becoming the 17th and final major pharma company to do so. All 17 targeted companies, representing 86% of the branded drug market, have now signed. Praluent will be listed on TrumpRx at $225, down from $537. And Lilly reports earnings tomorrow.
Top Story: Lilly Acquires Ajax Therapeutics for Up to $2.3B, Its Fifth Deal of the Year
What Happened: Eli Lilly announced a definitive agreement on April 27 to acquire Ajax Therapeutics, a privately held biopharmaceutical company developing next-generation JAK inhibitors for myeloproliferative neoplasms. The total deal value is up to $2.3 billion in cash, including an upfront payment and milestone payments upon clinical and regulatory achievements. Ajax is based in Cambridge, Massachusetts, and New York. Close is expected in the coming months.
The Science: Why Type II JAK2 Matters
All currently approved JAK2 inhibitors for myelofibrosis—ruxolitinib, fedratinib, pacritinib, and momelotinib—bind the Type I conformation of the JAK2 kinase. These drugs have been transformative for myelofibrosis patients, but a significant portion eventually develops resistance or loses response to Type I inhibitors, leaving them with limited treatment options.
Myelofibrosis is a rare, chronic blood cancer in which scar tissue builds up in the bone marrow, disrupting normal blood cell production. The disease is driven by dysregulated JAK2 signaling. When Type I inhibitors lose effectiveness, the underlying JAK2-driven disease progression continues unabated.
Ajax’s lead program, AJ1-11095, takes a fundamentally different approach. It is a first-in-class, once-daily oral Type II JAK2 inhibitor designed to bind the inactive conformation of JAK2—a structurally distinct binding mode from every approved therapy. This unique mechanism is intended to deliver deeper and more durable disease control and provide a treatment option for patients who develop resistance to existing Type I therapies.
AJ1-11095 is currently in Phase 1 (AJX-101 trial, NCT06343805) in patients with myelofibrosis who have previously been treated with a Type I JAK2 inhibitor. Dose selection for future registrational development is expected in 2026. Lilly Oncology president Jacob Van Naarden said the company looks forward to “the presentation of clinical proof-of-concept data later in 2026” and “rapidly advancing AJ1-11095 into registrational clinical trials.”
$19.8B in Five Deals: The Full Ledger
The Ajax acquisition brings Lilly’s 2026 M&A total to approximately $19.8 billion across five announced deals:
Orna Therapeutics (February): $2.4 billion. In vivo CAR-T for autoimmune diseases using circular RNA delivery.
Centessa Pharmaceuticals (March): $7.8 billion ($38 per share plus $9 CVR). OX2R agonist pipeline for narcolepsy and sleep-wake disorders. Lilly’s most significant push into neuroscience.
Kelonia Therapeutics (April 20): Up to $7 billion ($3.25 billion upfront). Lentiviral in vivo CAR-T for multiple myeloma. Second in vivo cell therapy platform.
CrossBridge Bio (April 22): Up to $300 million. Dual-payload ADC technology for oncology.
Ajax Therapeutics (April 27): Up to $2.3 billion. First-in-class Type II JAK2 inhibitor for myelofibrosis.
CNBC noted that Lilly also acquired Scorpion Therapeutics earlier this year, which would push the total even higher. The strategic logic across all five deals is consistent: Lilly is building a diversified oncology, cell therapy, and neuroscience franchise to extend growth beyond its GLP-1 dominance. Each acquisition targets a different therapeutic area or modality, creating portfolio diversification while reducing integration overlap since the teams and disease areas do not compete for the same organizational resources.
The Execution Risk Question
Five acquisitions in under three months is unprecedented for any large pharma company. Lilly has the balance sheet and cash generation from its GLP-1 franchise to fund the capital deployment, but organizational bandwidth is finite. Kelonia and Orna are both early-stage in vivo CAR-T platforms that may take years to generate revenue. Centessa’s lead OX2R agonist is in Phase 2. Ajax is Phase 1 with no proof-of-concept data yet. CrossBridge is a technology platform rather than a clinical-stage product.
All of this is happening while Lilly simultaneously launches Foundayo, its most important new product in years, files for a diabetes indication under the CNPV, and manages the regulatory and commercial infrastructure for Zepbound and Mounjaro. The question Lilly will need to answer on tomorrow’s Q1 earnings call is whether there is a sixth deal coming or whether the company is shifting to integration mode.
Our Pro brief analyzes why five acquisitions in three months is unprecedented, what the execution risk looks like across parallel integrations, and how the Type II JAK2 mechanism addresses the myelofibrosis resistance problem. [Details below.]
What to Watch
Ajax proof-of-concept data later in 2026 will be the first clinical test of the Type II JAK2 thesis. If the data shows meaningful responses in patients who have failed Type I inhibitors, it validates both the mechanism and the acquisition price. Dose selection for registrational development is also expected this year. Tomorrow’s Lilly earnings call will provide the first management commentary on how the company is structuring its integration approach across five simultaneous deals.
Regeneron Signs MFN Deal, Completing All 17 White House Agreements
What Happened: Regeneron signed a Most-Favored-Nation pricing agreement with the White House on April 23, becoming the 17th and final major pharmaceutical company to do so. The deal was announced in an Oval Office ceremony. Regeneron was the last holdout among the companies targeted by the administration in letters sent last July.
What Regeneron Agreed To
Regeneron committed to lowering Medicaid prices on all current and future drugs to MFN levels. Praluent (alirocumab, cholesterol) will be listed on TrumpRx at $225, down from $537—a 58% reduction. All new Regeneron medicines will receive MFN pricing for U.S. patients. Regeneron committed billions in U.S. manufacturing investment as part of the agreement. The company will also provide Otarmeni (gene therapy for genetic hearing loss, approved under the CNPV program) at no cost to U.S. patients.
All 17 Companies Are Now Signed
With Regeneron’s agreement, the MFN initiative now covers approximately 86% of the branded drug market, according to the White House. The full list of signatories: Pfizer, AstraZeneca, EMD Serono, Eli Lilly, Novo Nordisk, Amgen, Bristol Myers Squibb, Boehringer Ingelheim, Genentech, Gilead Sciences, GSK, Merck, Novartis, Sanofi, Johnson & Johnson, AbbVie, and Regeneron. STAT called it the close of “the first round of drug price negotiations.”
What the MFN Deals Actually Change
The political significance is clear: every major pharma company voluntarily agreed to pricing concessions under the threat of 100% tariffs. The practical impact is more nuanced.
What the deals cover: Medicaid pricing aligned to the lowest prices in comparable developed nations. Selected drugs listed on TrumpRx at discounted self-pay prices. U.S. manufacturing commitments totaling hundreds of billions in aggregate.
What the deals do not cover: Medicare Part D pricing, which is governed separately by the Inflation Reduction Act negotiation framework. Private insurance pricing, which is negotiated between drug companies and pharmacy benefit managers. The vast majority of U.S. drug spending flows through Medicare and private insurance, not Medicaid or self-pay channels.
Critics note that Medicaid already receives deep rebates, and TrumpRx reaches a limited patient base relative to the total insured population. The administration gets headlines about lower drug prices. Pharma gets tariff relief through the 0% exemption rate. Whether this constitutes structural drug pricing reform or performative compliance depends on perspective—but the mechanism has now achieved 100% participation among its targeted companies.
Our Pro brief includes the full MFN scorecard analyzing the actual pricing impact versus the political claims, which drugs are appearing on TrumpRx, and whether the framework will expand to Medicare and private insurance or remain limited to Medicaid. [Details below.]
Corporate Developments
Ligand Acquires XOMA Royalty for $739M
Ligand Pharmaceuticals announced a definitive agreement to acquire XOMA Royalty for approximately $739 million in cash ($39 per share, roughly 3% premium). The deal adds more than 120 treatments to Ligand’s portfolio, including seven marketed products with royalty streams from Roche’s Vabysmo, Servier’s Ojemda, and Zevra’s Miplyffa. At peak, Ligand expects Vabysmo royalties worth $37.5 million annually. The combined company will hold economic rights to more than 200 drugs in development or on the market. Ligand raised its 2026 revenue outlook to $270 million to $310 million (from $245 million to $285 million) and expects the acquisition to be immediately accretive. XOMA shares rose 9.7%.
Why This Matters: The Ligand/XOMA deal consolidates two of the largest royalty aggregation platforms in biopharma into a single entity with economic rights across more than 200 programs. Royalty aggregation has become an increasingly attractive business model because it provides diversified pharmaceutical revenue exposure without the R&D risk, manufacturing complexity, or commercial infrastructure costs of traditional drug development. The combined platform’s exposure to Vabysmo—one of the fastest-growing ophthalmology drugs globally—provides a high-visibility anchor revenue stream.
Strategic Themes
1. Lilly’s $19.8B Deal Spree Is Unprecedented in Pace and Scope
No large pharma company has executed five acquisitions totaling nearly $20 billion in under three months in recent memory. The breadth is equally notable: two in vivo CAR-T platforms (oncology and autoimmune), a narcolepsy franchise, a dual-payload ADC technology, and a first-in-class blood cancer drug. Lilly is not concentrating its bets in a single therapeutic area—it is building across oncology, cell therapy, neuroscience, and hematology simultaneously. The GLP-1 cash generation engine makes this possible. Whether the organizational bandwidth supports this many parallel integrations will be answered over the next 12 to 24 months.
2. The Type II JAK2 Thesis Could Address the Biggest Unmet Need in Myelofibrosis
Every approved JAK2 inhibitor binds the same conformation. When patients develop resistance—which a significant portion do—they have limited options. A Type II inhibitor that binds a fundamentally different conformation could provide a validated therapy for this resistant population. If Ajax’s proof-of-concept data later this year confirms the mechanism translates to clinical activity, Lilly would own the first treatment option for a population that currently has none. If the data is negative, Lilly will have paid $2.3 billion for a preclinical thesis that did not survive contact with human biology.
3. All 17 MFN Deals Are Signed—and the Real Pricing Impact Remains Debatable
100% compliance from 86% of the branded drug market is a political achievement. Whether it constitutes meaningful drug pricing reform is a separate question. The MFN deals primarily affect Medicaid pricing and TrumpRx self-pay listings. Medicare Part D and private insurance—where the majority of U.S. drug spending occurs—are not directly covered. The framework has demonstrated that tariff threats can force voluntary pricing concessions, but the concessions are concentrated in channels where prices were already discounted. The broader question is whether the administration uses this foundation to pursue more expansive pricing reform or treats it as a completed initiative.
4. Tomorrow’s Lilly Earnings Will Be the Most Watched Call of the Quarter
The April 30 call brings together every major Lilly narrative: Foundayo launch trajectory through mid-April, ACHIEVE-4 interpretation and diabetes filing timeline, five-acquisition integration strategy and whether a sixth is coming, Zepbound/Mounjaro revenue growth, and Section 232 tariff positioning now that all 17 MFN deals are signed. No other company faces this density of catalysts on a single earnings call. The market’s reaction will set the tone for the entire pharma sector heading into ASCO.
Frequently Asked Questions
What is Ajax Therapeutics, and what does Lilly get?
Ajax is developing AJ1-11095, a first-in-class Type II JAK2 inhibitor for myelofibrosis. Unlike all approved JAK2 inhibitors (ruxolitinib, fedratinib, pacritinib, momelotinib), which bind the Type I conformation, AJ1-11095 binds the Type II conformation, designed to deliver deeper disease control and overcome Type I resistance. The drug is in Phase 1 with proof-of-concept data expected later in 2026. Lilly is paying up to $2.3 billion.
How much has Lilly spent on M&A in 2026?
Approximately $19.8 billion across five announced acquisitions: Orna ($2.4B), Centessa ($7.8B), Kelonia (up to $7B), CrossBridge (up to $300M), and Ajax (up to $2.3B). CNBC noted Lilly also acquired Scorpion Therapeutics earlier this year, which would push the total even higher.
What is a Type II JAK2 inhibitor, and why does it matter?
All current JAK2 inhibitors bind the active (Type I) conformation of the kinase. Many myelofibrosis patients eventually develop resistance to these drugs. A Type II inhibitor binds the inactive conformation—a fundamentally different binding mode that may overcome Type I resistance mechanisms. If proof-of-concept data confirms clinical activity in resistant patients, AJ1-11095 would be the first validated therapy for this population.
Which companies signed MFN deals?
All 17 companies targeted by the White House: Pfizer, AstraZeneca, EMD Serono, Eli Lilly, Novo Nordisk, Amgen, Bristol Myers Squibb, Boehringer Ingelheim, Genentech, Gilead Sciences, GSK, Merck, Novartis, Sanofi, Johnson & Johnson, AbbVie, and Regeneron. Together they represent approximately 86% of the branded drug market.
What is Regeneron listing on TrumpRx?
Praluent (alirocumab, cholesterol) at $225, down from $537—a 58% reduction. Regeneron also committed to providing Otarmeni (gene therapy for genetic hearing loss) at no cost to U.S. patients and to making billions in U.S. manufacturing investment.
What is the Ligand/XOMA deal?
Ligand Pharmaceuticals is acquiring XOMA Royalty for $739 million ($39 per share). The deal combines two royalty aggregation platforms into a single entity with economic rights to more than 200 drugs. Key assets include royalties on Roche’s Vabysmo (peak $37.5 million annually), Servier’s Ojemda, and Zevra’s Miplyffa. Ligand raised its 2026 revenue outlook and expects the deal to be immediately accretive.
What should investors watch at Lilly earnings tomorrow?
Foundayo launch TRx data through mid-April, ACHIEVE-4 commentary and the diabetes filing timeline, five-acquisition integration strategy, whether a sixth deal is coming, Zepbound/Mounjaro revenue growth, and Section 232 tariff positioning. This is the most anticipated pharma earnings call of the quarter.
Do the MFN deals actually lower drug prices?
The deals lower Medicaid prices and create discounted self-pay listings on TrumpRx. They do not directly affect Medicare Part D or private insurance pricing, which is where the majority of U.S. drug spending occurs. Critics note that Medicaid already receives deep rebates, making the incremental impact modest. The political achievement—100% compliance from 86% of the branded market—is significant regardless of the economic magnitude.
BioMed Nexus Pro — What Institutional Subscribers Are Reading Today
Lilly’s $20B Deal Spree: Unprecedented Pace, Real Execution Risk. We analyze why five acquisitions in three months has no precedent in large-cap pharma, how Lilly is structuring integration across different therapeutic areas to minimize organizational conflict, and what the proof-of-concept data timeline for Ajax means for the blood cancer thesis.
Type II JAK2: The Myelofibrosis Resistance Opportunity. We break down why the Type II binding mode could address the biggest unmet need in myelofibrosis, model the market opportunity for a resistance-population therapy, and assess whether $2.3 billion is a rational price for a Phase 1 asset with no human data yet.
MFN Scorecard: All 17 Signed. We compile the complete list of MFN agreements, analyze the actual pricing impact versus political claims, identify which drugs are appearing on TrumpRx and at what discounts, and assess whether the framework will expand to Medicare and private insurance or remain limited to its current scope.
Plus: Lilly earnings preview, Ajax data timeline, Ligand/XOMA royalty platform analysis, and the updated catalyst calendar through ASCO and H2 2026.
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