AstraZeneca’s Tezspire meets key endpoints in Phase III EoE trial

Astrazeneca Plc (LON:AZN) has announced positive high-level results from the Phase III CROSSING trial in patients with eosinophilic esophagitis (EoE), showing that AstraZeneca and Amgen’s Tezspire (tezepelumab) demonstrated statistically significant and clinically meaningful improvements across both co-primary and all key secondary endpoints at week 24, which were sustained through week 52 in both doses tested. The co-primary endpoints were histologic remission and the frequency and severity of dysphagia (difficulty swallowing) compared with placebo. The safety profile of Tezspire in the trial was generally consistent with its approved indications.

CROSSING is a randomised, double-blind trial that evaluated the efficacy and safety of Tezspire administered subcutaneously every four weeks compared with placebo in adults and adolescents with symptomatic and uncontrolled EoE while on maintenance therapy.¹ In the trial, the first co-primary endpoint, histologic remission, was defined as having a low count of peak eosinophils in the oesophageal tissue.¹ 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.¹

EoE is a chronic and progressive epithelial-driven inflammatory disorder of the oesophagus affecting more than 470,000 people in the US, with the prevalence increasing five-fold since 2009.^2,3 The inflammation of the oesophagus can lead to dysphagia, food impaction and oesophageal narrowing.² 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 For patients, the risk of food moving slowly or becoming stuck can make daily meals difficult and stressful.⁷

Arjan Bredenoord, MD, Gastroenterologist and professor at the Amsterdam University Medical Center, Amsterdam, the Netherlands, and primary investigator in the trial, said: “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. 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 this disease, with the potential to help more patients achieve remission and symptom improvement.”

Sharon Barr, Executive Vice President, BioPharmaceuticals R&D, said: “The positive results of the Phase III CROSSING trial reinforce our confidence in the differentiated mechanism of action of Tezspire, which has now demonstrated clinically meaningful efficacy in a third epithelial-driven inflammatory disease. Epithelial science represents an important and rapidly evolving area in respiratory and immunology medicine, and we look forward to sharing these results at an upcoming medical meeting and with regulatory authorities as quickly as possible.”

Full results will be shared with regulatory authorities and the scientific community at an upcoming medical meeting.

Tezspire is a first-in-class human monoclonal antibody that inhibits the action of thymic stromal lymphopoietin (TSLP), a key epithelial cytokine that sits at the top of multiple inflammatory cascades. Tezspire is currently approved for the treatment of severe asthma in the US, EU, China, Japan and more than 70 countries across the globe, and for the treatment of chronic rhinosinusitis with nasal polyps (CRSwNP) in the US, EU, China and Japan. The Phase III JOURNEY and EMBARK trials evaluating Tezspire in chronic obstructive pulmonary disease (COPD) are ongoing.^8,9

References

1. ClinicalTrials.gov. Efficacy and Safety of Tezepelumab in Patients With Eosinophilic Esophagitis (CROSSING). Available at: https://clinicaltrials.gov/study/NCT05583227. [Last accessed August 2026].
2. Biedermann L. & Straumann A. Mechanisms and clinical management of eosinophilic oesophagitis: an overview. Nature Reviews Gastroenterol & Hepatol. 2023;20(2):101-119. 
3. Thel HL, et al. Prevalence and costs of eosinophilic esophagitis in the United States. Clin Gastroenterol Hepatol. 2025;23(2):272-280.e8. 
4. Hirano I, et al. AGA Institute and the Joint Task Force on Allergy-Immunology Practice Parameters clinical guidelines for the management of eosinophilic esophagitis. Gastroenterology. 2020;158(6):1776-1786. 
5. Strauss AL, Falk GW. Refractory eosinophilic esophagitis: what to do when the patient has not responded to proton pump inhibitors, steroids and diet. Curr Opin Gastroenterol. 2022;38(4):395-401. 
6. Lucendo AJ, et al. Efficacy of proton pump inhibitor drugs for inducing clinical and histologic remission in patients with symptomatic esophageal eosinophilia: a systematic review and meta-analysis. Clin Gastroenterol Hepatol. 2016; 14(1):13-22.e1.
7. Ho CN, et al. Patient experience with eosinophilic esophagitis symptoms and impacts on daily life based on in-trial qualitative interviews. J Patient Rep Outcomes. 2025;9(1):3. 
8. 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].
9. 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].