AbbVie will pay $100 million upfront to license a new investigational oral drug for inflammatory bowel disease from Cambridge, UK-based Nxera Pharma — a compound that works through a mechanism none of the existing IBD blockbusters can replicate. The deal, announced Tuesday and subject to HSR antitrust clearance, could be worth up to $1.47 billion in total if development and commercial milestones are hit, with tiered royalties on net sales on top of that.

The drug is NXE0033744, an oral small-molecule agonist of the EP4 receptor, a protein on the surface of intestinal epithelial cells. Where AbbVie’s own Skyrizi and Rinvoq — two of the most commercially successful IBD drugs ever made — suppress the immune cascades that drive intestinal inflammation, NXE0033744 targets something upstream and structurally different: the cellular death mechanism that breaks down the gut’s protective lining before those immune cascades even get started.

For the roughly 70 to 80 percent of moderate-to-severe IBD patients who do not achieve durable remission on current standard-of-care therapies, the distinction matters enormously. AbbVie is betting $1.47 billion that it matters commercially, too.

The $1.47 Billion Deal

Under the agreement signed Tuesday, AbbVie receives an exclusive worldwide license to develop and commercialize NXE0033744 for all inflammatory bowel disease indications — covering both Crohn’s disease and ulcerative colitis. Nxera receives $100 million on closing, plus up to $1.37 billion in development and commercial milestones, plus tiered royalties on net sales if the drug reaches the market.

Closing is conditional on antitrust clearance under the Hart-Scott-Rodino Antitrust Improvements Act, the standard U.S. review process for transactions of this size. No timeline for HSR clearance was disclosed.

The deal is not AbbVie’s first with Nxera. In 2022, the two companies entered a multi-target GPCR neuroscience collaboration under which Nxera’s structural biology team delivered stabilized receptor proteins to AbbVie for drug discovery work in neurological indications. That collaboration paid a $10 million Nxera milestone in June 2026 — meaning AbbVie committed $100 million to NXE0033744 within weeks of that separate payment, against the backdrop of an established working relationship with Nxera’s platform team.

Christopher Cargill, President and CEO of Nxera Pharma, described the deal as “a significant validation of our NxWave drug discovery platform and our strategy of developing gut-restricted therapeutics” in the company’s statement Tuesday.

What NXE0033744 Does That Skyrizi and Rinvoq Cannot

To understand why AbbVie would pay $100 million for a compound when it already commands what it describes as the leading share of new patient starts in IBD, it helps to understand what Skyrizi and Rinvoq actually do — and where they stop.

Skyrizi (risankizumab) is an IL-23 inhibitor: it blocks the interleukin-23 cytokine that drives the Th17 immune-cell pathway responsible for sustained intestinal inflammation. Rinvoq (upadacitinib) is a JAK1 inhibitor: it suppresses the JAK-STAT signaling network that immune cells use to amplify inflammatory responses. Both are powerful, both have transformed IBD outcomes for a subset of patients, and both generated a combined approximately $6.60 billion in Q1 2026 per AbbVie Q1 earnings — with AbbVie’s full-year guidance for the two drugs combined at approximately $31.8 billion for 2026.

But both drugs intervene in the immune signaling that happens after the intestinal epithelial barrier has already been compromised. Neither drug acts on the gut lining itself. Neither drug addresses the mechanism by which IBD’s vicious cycle begins: the death of the epithelial cells that form that lining.

NXE0033744 addresses exactly that mechanism.

How EP4 Agonism Breaks the IBD Vicious Cycle

The intestinal epithelium — the single-cell layer that lines the colon and separates its contents from the immune system — relies on a protective protein called the EP4 receptor to stay alive under inflammatory stress. EP4 is a G protein-coupled receptor (GPCR) encoded by the PTGER4 gene on chromosome 5. It is a receptor for prostaglandin E2, a signaling lipid the body produces during tissue stress. When prostaglandin E2 binds EP4 on intestinal epithelial cells, it triggers a signaling cascade through a G protein that elevates cyclic AMP inside the cell — and that cAMP signal converges on a cell-death regulatory node to prevent a form of cell death called necroptosis.

Necroptosis is not the same as apoptosis, the orderly programmed cell death that removes damaged cells without triggering immune responses. Necroptotic cell death is chaotic and inflammatory: a kinase called RIPK1 activates another kinase called RIPK3, which phosphorylates a protein called MLKL, which then punches holes in the cell’s plasma membrane. The cell ruptures and releases its contents — fragments of its own machinery, known as damage-associated molecular patterns, or DAMPs — into the surrounding tissue. Those DAMPs trigger a potent immune alarm signal.

In IBD, that alarm is what sustains the inflammatory cascade. Activated immune cells release TNF-alpha; TNF-alpha drives more necroptosis in neighboring epithelial cells; those cells release more DAMPs; more immune cells are recruited; more cells die. The barrier breaks down further. Bacteria that belong in the gut lumen cross into the tissue. The immune response amplifies. The cycle continues.

A 2021 study in Nature Cell Biology by Patankar and colleagues at the University of Erlangen-Nuremberg identified the EP4-to-RIPK1 pathway as the specific molecular brake that keeps this cycle from starting — and confirmed that suppressing EP4 signaling (or depleting prostaglandin E2 with NSAIDs) triggers necroptosis in intestinal epithelial cells and worsens colitis, while restoring EP4 signaling resolves it.

Genome-wide association studies had already identified variants in the PTGER4 gene as among the strongest genetic risk factors for Crohn’s disease, in a 2007 PTGER4 Crohn’s GWAS and subsequent studies — meaning the EP4 receptor’s connection to IBD has genetic validation from human population data, not just laboratory experiments.

NXE0033744 is a selective, small-molecule agonist of EP4: it activates the receptor and thereby suppresses the RIPK1-MLKL necroptotic cascade, allowing the epithelial barrier to maintain its integrity under inflammatory stress. No existing approved IBD drug acts on this mechanism.

Why gut restriction matters. EP4 is not expressed only in the intestine. It is found in bone, cardiovascular tissue, the lungs, and elsewhere in the body. Systemic activation of EP4 can produce vasodilation, cardiovascular effects, and broad immunomodulatory effects that would be undesirable — and potentially dangerous — as an IBD treatment. Nxera designed NXE0033744 to remain concentrated in the gastrointestinal tract and to be minimally absorbed into systemic circulation, containing its pharmacodynamic effect to the colonic epithelium where it is therapeutically needed. This design decision is what the company calls a “gut-restricted” profile.

The Platform Behind the Drug

NXE0033744 came out of Nxera Pharma’s NxWave platform, a five-step GPCR drug discovery engine built around the company’s core structural biology capability.

The platform starts with target identification and genetic validation — in this case, the GWAS data linking PTGER4 variants to Crohn’s disease susceptibility. It then moves to structural determination using what Nxera calls NxStaR technology: the company engineers thermostabilized versions of GPCR proteins that hold their three-dimensional shape long enough for high-resolution structure determination by X-ray crystallography and cryo-electron microscopy. GPCR structures are notoriously difficult to resolve because these proteins are membrane-embedded and highly flexible; Heptares (the company that became Nxera Pharma after the 2015 acquisition by Sosei Group) pioneered the thermostabilization approach that made it tractable.

With a resolved EP4 structure in hand, Nxera’s NxHit discovery step uses the three-dimensional binding pocket to screen compound libraries virtually — filtering for molecules with the right shape and chemistry to fit the receptor — supplemented by physical screening of GPCR-focused compound collections and DNA-encoded library (DEL) methods. Hits from that screen are then optimized through NxDesign, a structure-based design cycle that uses the crystal structure to guide iterative medicinal chemistry improvements to selectivity, potency, and pharmacokinetic properties.

The final step — the gut-restriction profile that defines NXE0033744 — reflects pharmaceutical optimization for GI-local delivery: maximizing colonic epithelial exposure while minimizing systemic plasma levels, a design constraint informed by the cardiovascular and immunological risks of systemic EP4 agonism described above.

Nxera currently applies the NxWave platform across a pipeline that includes M4 muscarinic receptor agonists (for CNS indications in collaboration with Neurocrine Biosciences), other GPCR-targeted programs in neurodegeneration and cardiovascular disease, and the neuroscience collaboration with AbbVie that predates Tuesday’s IBD deal.

The Treatment Gap That Made This Deal Worth $1.47 Billion

Approximately 3.1 million U.S. adults have IBD, based on 2015 National Health Interview Survey data published by the Centers for Disease Control and Prevention — a figure broadly confirmed by the American Gastroenterological Association’s 2024 white paper. Worldwide, more than 10 million people live with Crohn’s disease or ulcerative colitis.

The clinical reality behind those numbers is that current therapies fall far short of what patients need. Despite the considerable commercial success of anti-TNF biologics, IL-23 inhibitors, and JAK inhibitors, Takeda estimated in 2025 that only 20 to 30 percent of IBD patients achieve sustained clinical remission on existing treatments. A FiercePharma survey of gastroenterologists found that 81 percent ranked achieving clinical remission among their top three most urgent unmet needs in ulcerative colitis specifically — a measure of how widely physicians recognize the therapeutic ceiling.

That ceiling is partly structural. Existing drug classes all intervene in the immune-signaling cascades that drive intestinal inflammation. But a patient who fails one mechanism class and then another and then a third has not simply had bad luck with individual drugs; they may have an underlying disease biology in which the inflammatory response is regenerating itself from an epithelial barrier that is continuously failing. For those patients, a drug that acts at the barrier level — preventing the initial necroptotic breakdown rather than responding to its immune consequences — represents a mechanistically orthogonal option that the existing drug landscape does not contain.

The commercial logic for AbbVie follows directly: even at a projected market share far smaller than Skyrizi’s or Rinvoq’s, a drug that serves patients those two drugs cannot help would be additive to, not competitive with, AbbVie’s existing IBD franchise.

What Phase 1 Showed

NXE0033744 first entered human testing in March 2024. The completed Phase 1 program included standard single-ascending-dose (SAD) and multiple-ascending-dose (MAD) cohorts to assess safety, tolerability, and pharmacokinetics, plus a cohort specifically enrolling patients with active ulcerative colitis, plus a mechanistic challenge cohort.

The mechanistic challenge was particularly important for confirming the drug’s gut-restricted profile. Participants received indomethacin — a non-steroidal anti-inflammatory drug that suppresses prostaglandin E2 synthesis — which predictably increases intestinal permeability as endogenous EP4 signaling falls. When NXE0033744 was co-administered, it reduced that indomethacin-induced intestinal permeability increase. This confirmed two things simultaneously: that the drug is engaging EP4 receptors in the gut, and that it is doing so with sufficient local exposure to produce a pharmacodynamic effect.

Across all Phase 1 cohorts, no adverse events of concern were reported. The clean safety readout — combined with the confirmed pharmacodynamic signal in the indomethacin challenge — was the basis for AbbVie’s decision to license the compound before Phase 2 efficacy data exist. AbbVie will now conduct Phase 2 development under the terms of the deal.

AbbVie’s Bigger IBD Picture

AbbVie’s $1.47 billion commitment to NXE0033744 fits a consistent pattern: the company has been systematically building a multi-mechanism IBD portfolio to extend its franchise beyond the eventual generic erosion of Skyrizi and Rinvoq.

Skyrizi (risankizumab) generated approximately $4.48 billion in net revenue in the first quarter of 2026, up 29.2 percent year-over-year, and approximately $5.5 billion in the second quarter, up 24 percent. Rinvoq (upadacitinib) generated approximately $2.12 billion in Q1 2026, up 20.2 percent, and approximately $2.53 billion in Q2 2026, up 24.5 percent. AbbVie’s full-year 2026 guidance calls for approximately $21.6 billion from Skyrizi and approximately $10.2 billion from Rinvoq — a combined $31.8 billion from two IBD-focused drugs launched this decade.

But AbbVie is also running a Phase 2b trial of Skyrizi in combination with ABBV-382, its investigational anti-integrin antibody, in IBD. It acquired Apogee Therapeutics — a next-generation immunology company focused on atopic dermatitis and asthma — in a deal worth approximately $10.9 billion announced in June 2026.

NXE0033744 adds a third strategic layer: a drug that could work in IBD patients who have already failed Skyrizi, Rinvoq, anti-TNF biologics, and vedolizumab — the population for whom no approved mechanism currently offers a meaningful rescue option.

What This Means for Patients

NXE0033744 is not approved. It has completed Phase 1 safety testing; it has not yet demonstrated efficacy in a randomized controlled trial. The Phase 2 program, which will be sponsored and executed by AbbVie, has not yet been announced.

For the roughly two million or more IBD patients in the U.S. who lack durable remission on existing therapies, the significance of Tuesday’s deal is that a drug with a genuinely novel mechanism has cleared early safety testing and attracted the resources of one of the world’s largest immunology franchises to push it through the development process. If Phase 2 efficacy results confirm the mechanistic hypothesis — that EP4 agonism restores the epithelial barrier independently of the immune cascades targeted by all current approved drugs — it would represent the first IBD therapy to work at the cellular level where the inflammatory cycle begins rather than in the immune system that sustains it.

That is the bet AbbVie is making. The price it is paying to find out is $1.47 billion.

Frequently Asked Questions

What is NXE0033744 and what does it do?

NXE0033744 is an experimental oral medication designed to treat inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis. It works by activating a protein called the EP4 receptor on the cells that line the intestinal wall. When EP4 is activated, it suppresses a cell-death process called necroptosis that breaks down the gut lining in IBD patients. No currently approved IBD drug works this way.

How is this drug different from existing IBD treatments like Skyrizi or Rinvoq?

Skyrizi and Rinvoq are biologics and small molecules that target immune-signaling pathways — the cytokine and kinase cascades that sustain intestinal inflammation after the gut lining has already been damaged. NXE0033744 targets the cellular event that initiates the damage cycle: the death of the epithelial cells that form the gut’s protective barrier. The two approaches are mechanistically complementary rather than competitive, which is part of why AbbVie — maker of Skyrizi and Rinvoq — wanted this drug.

What does “gut-restricted” mean, and why does it matter?

The EP4 receptor is found in multiple tissues throughout the body, not only in the gut. If a drug strongly activates EP4 everywhere, it could cause unintended cardiovascular or immunological effects. Nxera designed NXE0033744 to remain concentrated in the gastrointestinal tract, producing its therapeutic effect locally while minimizing absorption into the bloodstream. Phase 1 data confirmed this design worked as intended.

What did Phase 1 trials show?

The Phase 1 program, which completed in 2026, found no adverse events of concern across its dose-escalation and patient cohorts. A pharmacodynamic challenge test — in which participants received an NSAID that depletes the gut’s natural EP4 signaling — confirmed that NXE0033744 engaged its target in the gut and produced a measurable biological response (reduced intestinal permeability). No Phase 2 efficacy data are yet available.

What is the AbbVie–Nxera deal structure?

AbbVie pays $100 million upfront for an exclusive worldwide license to develop and commercialize NXE0033744 for all IBD indications. Nxera can earn up to $1.37 billion in development and commercial milestone payments, plus tiered royalties on net sales if the drug reaches the market. The agreement is subject to U.S. Hart-Scott-Rodino antitrust clearance. AbbVie will now run the Phase 2 program.