THOUSAND OAKS, Calif. — Amgen (NASDAQ:AMGN) and AstraZeneca today announced positive top-line results from the Phase 3 CROSSING trial of TEZSPIRE® (tezepelumab-ekko) in patients living with eosinophilic esophagitis (EoE). TEZSPIRE demonstrated statistically significant and clinically meaningful improvements across co-primary and key secondary endpoints at week 24 which were sustained through week 52. The co-primary endpoints were histologic remission and the frequency and severity of dysphagia (difficulty swallowing). The safety profile of TEZSPIRE was generally consistent with its approved indications.
EoE is a chronic and progressive epithelial-driven inflammatory disorder of the esophagus affecting more than 470,000 people in the U.S., with the prevalence increasing five-fold since 2009.1,2 Esophageal inflammation can lead to dysphagia, food impaction and esophageal narrowing.2 For patients, the risk of food moving slowly or becoming stuck can make daily meals difficult and stressful.3 Nearly half of patients, including adolescents, do not achieve adequate disease control with current first-line treatments, which include dietary restriction, swallowed topical corticosteroids and proton pump inhibitors.4-6
“We’re pleased that TEZSPIRE showed efficacy in a third epithelial-driven inflammatory condition, eosinophilic esophagitis,” said Jay Bradner, M.D., executive vice president of Research and Development, Artificial Intelligence and Data at Amgen. “In this Phase 3 trial, TEZSPIRE improved both the underlying inflammation and the swallowing difficulties that can make eosinophilic esophagitis so disruptive for patients. That combination is important for patients and builds confidence in TEZSPIRE as a potential new treatment for people struggling with EoE.”
CROSSING is a randomized, double-blind trial that evaluated the efficacy and safety of TEZSPIRE at one of two doses administered subcutaneously every four weeks compared to placebo in adults and adolescents with symptomatic and uncontrolled EoE while on maintenance therapy. In the trial, the first co-primary endpoint, histologic remission, was defined as having a low count of peak eosinophils in the esophageal tissue. The second co-primary endpoint, the frequency and severity of dysphagia, was assessed using the patient-reported Dysphagia Symptom Questionnaire (DSQ) and measured as a mean change from baseline in DSQ score.7
“Despite the availability of first-line therapies or dietary interventions, many patients with eosinophilic esophagitis still experience substantial burden, including difficulty swallowing food and emotional and daily-life impacts of the disease,” said Arjan Bredenoord, M.D., gastroenterologist and professor at the Amsterdam University Medical Center, Amsterdam, the Netherlands, and primary investigator in the trial. “The impressive results from the CROSSING trial sustained over 52 weeks demonstrate that tezepelumab, taken every four weeks, could provide a new approach to treating EoE, with the potential to help more patients achieve remission and symptom improvement.”
Full results will be shared with regulatory authorities and the scientific community at an upcoming medical meeting.
TEZSPIRE® (tezepelumab-ekko) U.S. Indication
TEZSPIRE is indicated for:
- the add-on maintenance treatment of adult and pediatric patients aged 12 years and older with severe asthma. TEZSPIRE is not indicated for the relief of acute bronchospasm or status asthmaticus.
- the add-on maintenance treatment of adult and pediatric patients aged 12 years and older with inadequately controlled chronic rhinosinusitis with nasal polyps (CRSwNP).
TEZSPIRE® (tezepelumab-ekko) Important Safety Information
CONTRAINDICATIONS
Known hypersensitivity to tezepelumab-ekko or excipients.
WARNINGS AND PRECAUTIONS
Hypersensitivity Reactions
Hypersensitivity reactions were observed in the clinical trials (e.g., rash and allergic conjunctivitis) following the administration of TEZSPIRE. Postmarketing cases of anaphylaxis have been reported. These reactions can occur within hours of administration, but in some instances have a delayed onset (i.e., days). In the event of a hypersensitivity reaction, consider the benefits and risks for the individual patient to determine whether to continue or discontinue treatment with TEZSPIRE.
Acute Asthma Symptoms or Deteriorating Disease
TEZSPIRE should not be used to treat acute asthma symptoms, acute exacerbations, acute bronchospasm, or status asthmaticus.
Abrupt Reduction of Corticosteroid Dosage
Do not discontinue systemic or inhaled corticosteroids abruptly upon initiation of therapy with TEZSPIRE. Reductions in corticosteroid dose, if appropriate, should be gradual and performed under the direct supervision of a physician. Reduction in corticosteroid dose may be associated with systemic withdrawal symptoms and/or unmask conditions previously suppressed by systemic corticosteroid therapy.
Parasitic (Helminth) Infection
It is unknown if TEZSPIRE will influence a patient’s response against helminth infections. Treat patients with pre-existing helminth infections before initiating therapy with TEZSPIRE. If patients become infected while receiving TEZSPIRE and do not respond to anti-helminth treatment, discontinue TEZSPIRE until infection resolves.
Live Attenuated Vaccines
The concomitant use of TEZSPIRE and live attenuated vaccines has not been evaluated. The use of live attenuated vaccines should be avoided in patients receiving TEZSPIRE.
ADVERSE REACTIONS
The most common adverse reactions (incidence ≥ 3%) are:
- Asthma: pharyngitis, arthralgia, and back pain.
- Chronic rhinosinusitis with nasal polyps: nasopharyngitis, upper respiratory tract infection, epistaxis, pharyngitis, back pain, influenza, injection site reaction and arthralgia.
USE IN SPECIFIC POPULATIONS
There are no available data on TEZSPIRE use in pregnant women to evaluate for any drug-associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. Placental transfer of monoclonal antibodies such as tezepelumab-ekko is greater during the third trimester of pregnancy; therefore, potential effects on a fetus are likely to be greater during the third trimester of pregnancy.
Please see the full Prescribing Information including Patient Information and Instructions for Use.
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About TEZSPIRE® (tezepelumab-ekko)
TEZSPIRE is a first-in-class human monoclonal antibody that works on a primary source of inflammation: the airway and gut epithelia, which are the first points of contact for many viruses, allergens, pollutants and other environmental triggers and insults. Specifically, TEZSPIRE targets and blocks thymic stromal lymphopoietin (TSLP), a key epithelial cytokine that sits at the top of multiple inflammatory cascades and initiates an overreactive immune response to allergic, eosinophilic and other types of epithelial-driven inflammation associated with severe asthma, chronic rhinosinusitis with nasal polyps (CRSwNP), chronic obstructive pulmonary disease (COPD) and eosinophilic esophagitis (EoE).7,8-11
TSLP is released by the epithelium in response to inhaled or swallowed environmental inflammatory triggers. Across these disease states, the expression of TSLP is increased and correlates with disease severity.8-12
TEZSPIRE is currently approved for the treatment of severe asthma in the U.S., EU, China, Japan and more than 70 countries across the globe, and for the treatment of inadequately controlled CRSwNP in the U.S., EU, China and Japan.
Beyond severe asthma and CRSwNP, TEZSPIRE is also in development for other potential indications including COPD and EoE.13-15
About Eosinophilic Esophagitis (EoE)
EoE is a chronic and progressive epithelial-driven inflammatory disorder of the esophagus with prevalence growing across the world.1,2 It is characterized by inflammation, remodeling and esophageal epithelial dysfunction. Epithelial dysfunction and inflammation are important characteristics of EoE and impede the ability of the epithelium to act as a physical and immunological barrier against the external environment.2
The most common symptoms of EoE include difficulty and pain swallowing, food becoming stuck in the esophagus (which may require emergency medical interventions), nausea and vomiting, abdominal or chest pain, poor appetite and difficulty sleeping.2,16,17 Many patients, including adolescents, experience a substantial impact on their quality of life including significant anxiety related to swallowing and choking, depression and decreased work/school productivity.18,19
Patients are often treated with proton pump inhibitors or swallowed topical corticosteroids to manage inflammation.2,4 Nearly half of patients with EoE will not respond to standard first-line therapies or dietary treatment.5,6 Existing treatment options, including those targeting downstream mediators, may not fully address epithelial-driven inflammation.20,21
About the Phase 3 CROSSING Trial
CROSSING is a randomized, double-blind, placebo-controlled, multi-center, parallel-group, Phase 3 trial designed to evaluate the efficacy and safety of TEZSPIRE administered subcutaneously every four weeks, compared to placebo in patients aged 12-80 years with symptomatic and histologically active EoE. A total of 368 patients were randomized in a 1:1:1 ratio to receive either a low or high dose of TEZSPIRE or placebo.7
The co-primary endpoints analyzed at week 24 were the proportion of patients with histologic remission, defined as a peak esophageal eosinophil count less than or equal to six eosinophils per high-power field, and mean changes from baseline in the Dysphagia Symptom Questionnaire (DSQ). The peak eosinophil count is obtained when biopsies of the tissue of the esophagus are examined under a microscope. A count of 15 or more peak eosinophils per high power microscopic field measured by esophageal biopsy is often the cutoff used to diagnose EoE.22,23 The DSQ captures the presence and severity of dysphagia symptoms in a daily diary with a four-item patient-reported questionnaire; the score is calculated over 14-day periods, ranging from zero to 84, with a higher score indicating more severe dysphagia. Key secondary endpoints assessed histologic remission and dysphagia symptoms at week 52; changes in endoscopic disease features (EoE-EREFS) and histologic severity and extent (EoE-HSS) at weeks 24 and 52, as well as endoscopic response, inflammatory remission and total endoscopic remission at week 52.7
In the trial, patients were allowed to remain on background medications for EoE, including proton pump inhibitors and swallowed topical corticosteroids, provided that they were stable prior to entry and during the treatment period.7
About the Amgen and AstraZeneca Collaboration
Amgen is in a collaboration with AstraZeneca for the development and commercialization of TEZSPIRE. Under the collaboration, both companies share global costs, profits and losses equally after payment by AstraZeneca of a mid-single-digit royalty to Amgen. AstraZeneca leads global development. In North America, Amgen, as the principal, recognizes product sales of TEZSPIRE in the United States, and AstraZeneca, as the principal, recognizes product sales of TEZSPIRE in Canada. AstraZeneca leads commercialization for TEZSPIRE outside North America. Amgen manufactures and supplies TEZSPIRE worldwide.
About Amgen
Amgen discovers, develops, manufactures and delivers innovative medicines to fight some of the world’s toughest diseases. Harnessing the best of biology and technology, Amgen reaches millions of patients with its medicines.
More than 45 years ago, Amgen helped establish the biotechnology industry at its U.S. headquarters in Thousand Oaks, California, and it remains at the cutting edge of innovation, using technology and human genetic data to push beyond what is known today. Amgen is advancing a broad and deep pipeline and portfolio of medicines to treat cancer, heart disease, inflammatory conditions, rare diseases and obesity and obesity-related conditions.
Amgen has been consistently recognized for innovation and workplace culture, including honors from Fast Company and Forbes. Amgen is one of the 30 companies that comprise the Dow Jones Industrial Average® and it is also part of the Nasdaq-100 Index®, which includes the largest and most innovative non-financial companies listed on the Nasdaq Stock Market based on market capitalization.
For more information, visit Amgen.com and follow Amgen on X, LinkedIn, Instagram, YouTube, Facebook, TikTok and Threads.
Amgen Contacts
Elissa Snook, 609-251-1407 (media)
Casey Capparelli, 805-447-1746 (investors)
References
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- Varricchi G, et al. Thymic Stromal Lymphopoietin Isoforms, Inflammatory Disorders, and Cancer. Front Immunol. 2018;9:1595.
- Ying S, et al. Thymic stromal lymphopoietin expression is increased in asthmatic airways and correlates with expression of Th2-attracting chemokines and disease severity. J Immunol. 2005;174:8183-8190.
- Calderon AA, et al. Targeting interleukin-33 and thymic stromal lymphopoietin pathways for novel pulmonary therapeutics in asthma and COPD. Eur Respir Rev. 2023;32(167):220144.
- Nagarkar DR, et al. Thymic stromal lymphopoietin activity is increased in nasal polyps of patients with chronic rhinosinusitis. J Allergy Clin Immunol. 2013;132(3):593-600.e12.
- Sherrill JD, et al. Preferential Secretion of Thymic Stromal Lymphopoietin (TSLP) by Terminally Differentiated Esophageal Epithelial Cells: Relevance to Eosinophilic Esophagitis. PLoS One. 2016;11(2):e0148216.
- ClinicalTrials.gov. A Study to Investigate the Efficacy and Safety of Tezepelumab in Adult Participants With Moderate to Very Severe COPD (D5241C00007) (JOURNEY). Available at: https://clinicaltrials.gov/study/NCT06878261. [Last accessed August 2026].
- ClinicalTrials.gov. A Study to Investigate the Efficacy and Safety of Tezepelumab in Adult Participants With Moderate to Very Severe COPD (D5241C00006) (EMBARK). Available at: https://clinicaltrials.gov/study/NCT06883305. [Last accessed August 2026].
- ClinicalTrials.gov. Tezepelumab COPD Exacerbation Study (COURSE). Available at: https://clinicaltrials.gov/ct2/show/NCT04039113. [Last accessed: August 2026].
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- MedlinePlus. Eosinophilic esophagitis. Bethesda (MD): National Library of Medicine (US). Available at: https://medlineplus.gov/eosinophilicesophagitis.html. [Last accessed August 2026].
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- Harris RF, et al. Psychosocial dysfunction in children and adolescents with eosinophilic esophagitis. J Pediatr Gastroenterol Nutr. 2013;57:500–5.
- Underwood B, et al. Breaking down the complex pathophysiology of eosinophilic esophagitis. Ann Allergy Asthma Immunol. 2023;130(1):28-39
- Gautam R, et al. Eosinophilic esophagitis: mechanisms of disease and approach to treatment. Curr Allergy Asthma Rep. 2026;26:21.
- Lucendo AJ, et al. British Society of Gastroenterology (BSG) and British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN) joint consensus guidelines on the diagnosis and management of eosinophilic oesophagitis in children and adults. Gut. 2022;71(8):1459-1487.
- Dellon ES, et al. ACG Clinical Guideline: Diagnosis and Management of Eosinophilic Esophagitis. Am J Gastroenterol. 2025;120(1):31-59.
