TEZSPIRE eosinophilic esophagitis data unveiled on August 27, 2026, mark a potential turning point for patients living with the chronic swallowing disorder. Amgen (NASDAQ: AMGN) and AstraZeneca announced positive top-line results from the Phase 3 CROSSING trial, reporting that TEZSPIRE® (tezepelumab-ekko) achieved statistically significant and clinically meaningful improvements across both co-primary endpoints and all key secondary endpoints. The companies said the benefits observed at week 24 were sustained through week 52, reinforcing the durability of the treatment effect in a difficult-to-manage disease.
The co-primary endpoints in the trial were histologic remission and the frequency and severity of dysphagia, commonly described as difficulty swallowing. Both measures showed clear separation from placebo, according to the companies’ announcement. Amgen and AstraZeneca also noted that the safety profile of TEZSPIRE in the eosinophilic esophagitis population was generally consistent with the drug’s already-approved indications, an important signal for regulators and physicians evaluating a potential new use for the biologic. Taken together, the TEZSPIRE eosinophilic esophagitis dataset represents one of the larger biologic trial programs conducted to date in this specific disease.
Eosinophilic esophagitis, often abbreviated as EoE, is a chronic and progressive inflammatory disorder of the esophagus that now affects more than 470,000 people in the United States, with prevalence increasing roughly five-fold since 2009. The disease can cause food to move slowly through the esophagus or become stuck, a complication known as food impaction that sometimes requires emergency care. For many patients, the unpredictability of meals creates daily anxiety layered on top of physical discomfort.
Nearly half of patients, including adolescents, fail to achieve adequate disease control on current first-line therapies such as dietary restriction, swallowed topical corticosteroids and proton pump inhibitors. That treatment gap is central to why the TEZSPIRE eosinophilic esophagitis program has drawn close attention from gastroenterologists and investors tracking Amgen’s broader inflammation pipeline.
TEZSPIRE Eosinophilic Esophagitis Results Build on Two Other Indications
Jay Bradner, M.D., executive vice president of Research and Development, Artificial Intelligence and Data at Amgen, framed the CROSSING results as validation of the drug’s underlying biology rather than a one-off finding. “We’re pleased that TEZSPIRE showed efficacy in a third epithelial-driven inflammatory condition, eosinophilic esophagitis,” Bradner said. “In this Phase 3 trial, TEZSPIRE improved both the underlying inflammation and the swallowing difficulties that can make eosinophilic esophagitis so disruptive for patients.” Bradner’s comment reflects how central the TEZSPIRE eosinophilic esophagitis findings have become to Amgen’s broader inflammation strategy.
That comment points to a broader strategic narrative Amgen and AstraZeneca have been building since TEZSPIRE’s original approval for severe asthma. TEZSPIRE is a first-in-class human monoclonal antibody that blocks thymic stromal lymphopoietin, or TSLP, an epithelial cytokine that sits upstream of multiple inflammatory cascades. Because TSLP is released by the airway and gut epithelia in response to allergens, pollutants and other environmental triggers, the companies have long argued that blocking it could benefit several epithelial-driven diseases beyond asthma, including chronic rhinosinusitis with nasal polyps, chronic obstructive pulmonary disease and now eosinophilic esophagitis.
Arjan Bredenoord, M.D., a gastroenterologist and professor at the Amsterdam University Medical Center who served as a primary investigator on CROSSING, said the sustained 52-week data suggest tezepelumab could offer a meaningfully different option for patients who have exhausted standard care. He noted that many people with eosinophilic esophagitis continue to struggle with swallowing difficulty and quality-of-life effects even when using first-line therapies or dietary interventions. His independent clinical perspective adds weight to the TEZSPIRE eosinophilic esophagitis efficacy data reported by the two companies.
TEZSPIRE Eosinophilic Esophagitis Trial Design: Inside CROSSING
CROSSING is a randomized, double-blind, placebo-controlled, multi-center, parallel-group study that enrolled 368 patients aged 12 to 80 years with symptomatic and histologically active eosinophilic esophagitis. Participants were randomized in a 1:1:1 ratio to a low dose of TEZSPIRE, a high dose of TEZSPIRE, or placebo, with study drug administered subcutaneously every four weeks. Patients were permitted to remain on stable background medications, including proton pump inhibitors and swallowed topical corticosteroids, throughout the treatment period. CROSSING is the pivotal study underpinning the TEZSPIRE eosinophilic esophagitis regulatory package the companies expect to advance toward health authorities.
The first co-primary endpoint, histologic remission, was defined as a peak esophageal eosinophil count of six or fewer eosinophils per high-power field at week 24, measured through biopsy. For context, a count of 15 or more peak eosinophils per high-power field is often the diagnostic threshold used to confirm eosinophilic esophagitis in the first place, illustrating how substantial the required reduction is for a patient to be classified in remission. The second co-primary endpoint tracked mean change from baseline in the Dysphagia Symptom Questionnaire, a four-item, patient-reported diary scored from zero to 84 over rolling 14-day periods, with higher scores reflecting more severe swallowing difficulty.
What the Secondary Endpoints Add to the TEZSPIRE Eosinophilic Esophagitis Story
Beyond the co-primary measures, CROSSING assessed histologic remission and dysphagia symptoms again at week 52, along with changes in endoscopic disease features and histologic severity and extent at both week 24 and week 52. The trial also captured endoscopic response, inflammatory remission and total endoscopic remission at week 52. Amgen and AstraZeneca said TEZSPIRE met all of these key secondary endpoints, a result that supports the durability argument the companies are making to regulators. Collectively, these figures strengthen the TEZSPIRE eosinophilic esophagitis durability narrative beyond the initial week 24 readout.
Full data from CROSSING have not yet been published in a peer-reviewed journal; the companies said complete results will be presented to regulatory authorities and shared with the scientific community at an upcoming medical meeting. That sequencing is standard for large Phase 3 programs and typically precedes formal regulatory filings for a new indication.
Commercial and Regulatory Context for TEZSPIRE Eosinophilic Esophagitis
TEZSPIRE is currently approved as an add-on maintenance treatment for severe asthma in patients aged 12 and older across the United States, European Union, China, Japan and more than 70 other countries, and for inadequately controlled chronic rhinosinusitis with nasal polyps in the U.S., EU, China and Japan. It is not indicated for relief of acute bronchospasm or status asthmaticus. Beyond eosinophilic esophagitis, the drug is also in development for chronic obstructive pulmonary disease, according to the companies.
Under the companies’ long-standing collaboration, AstraZeneca leads global development of TEZSPIRE and commercialization outside North America, while Amgen manufactures and supplies the product worldwide. In North America, Amgen recognizes product sales in the United States and AstraZeneca recognizes sales in Canada, with the two companies sharing global costs, profits and losses equally after AstraZeneca pays Amgen a mid-single-digit royalty. Positive Phase 3 data in a third indication could extend that revenue-sharing arrangement into a new and currently underserved patient population if regulators ultimately approve the eosinophilic esophagitis use. Analysts covering both companies will likely treat the TEZSPIRE eosinophilic esophagitis opportunity as an incremental rather than transformative revenue driver until peak sales guidance is disclosed.
