Dupilumab

iStock, Ja_inter Even without specific Phase 3 data yet revealed, analysts see AstraZeneca and Amgen’s Tezspire as a potential threat for Dupixent in eosinophilic esophagitis. With a late-stage esophagitis win on Thursday, AstraZeneca and Amgen’s Tezspire is set up for further growth in the immunology arena—and, analysts believe, could even challenge one of the space’s biggest and most entrenched franchises. Dupixent is the only approved biologic in eosinophilic esophagitis (EoE), William Blair analysts wrote in a Thursday note to investors. And while much remains unknown about the competitive pro the up-and-comer, Tezspire could emerge as a formidable challenger to the blockbuster drug. Co-owned by Sanofi and Regeneron, Dupixent was first approved in March 2017 for eczema. The IL-4 and IL-13 blocker entered the EoE arena in May 2022, buoyed by pivotal data showing that about 60% of treated patients achieved histologic remission, as compared with up to 6% of placebo comparators. Difficulty swallowing (dysphagia), a common symptom of EoE, improved by 21.9 to 23.8 points in those on Dupixent, as measured by a validated questionnaire, versus 9.6 to 13.9 points on placebo. This is the bar that Tezspire must clear in order to step up to Dupixent, Truist Securities said Thursday—noting, however, that Tezspire already has clear “differentiation on dosing.” AstraZeneca and Amgen’s drug requires an injection every four weeks, while Dupixent is administered via injection weekly. “Tezspire’s potential competitiveness in EoE is a nice incremental win,” the firm said. Whether Tezspire can indeed pose a threat to Dupixent remains to be seen. In the Phase 3 readout on Thursday, AstraZeneca and Amgen said that their drug significantly improved histologic remission and dysphagia symptoms at 24 weeks, sustained through 52 weeks. But the partners didn’t provide specific data to back up their claims, meaning the magnitude of Tezspire’s benefits remain unknown at this time. Immunology and inflammation AstraZeneca, Amgen notch another late-stage win for Tezspire, this time in esophagitis AstraZeneca and Amgen co-develop and co-commercialize Tezspire under an April 2012 agreement. The partners are now planning another FDA submission for the asthma drug, which received an expansion into chronic rhinosinusitis last year. August 27, 2026 · 2 min read · Tristan Manalac Read more AstraZeneca and Amgen will present full data from the late-stage study, dubbed CROSSING, at an upcoming scientific conference. There has been no head-to-head study directly comparing Tezspire against Dupixent for EoE. But even lacking details, Truist called CROSSING “a clean win” for Amgen and AstraZeneca, providing “a genuine addition to the Tezspire franchise, and demonstrative of additional opportunities for growth worth watching across a maturing commercial portfolio.” Tezspire is already a high-growth franchise for the pharma partners. The drug brought in $1.48 billion in revenue for Amgen in 2025, a 51% year-on-year increase. AstraZeneca, meanwhile, logged $1.13 billion in ex-U.S. sales for Tezspire last year, surging 64%. William Blair on Thursday forecast worldwide sales for the drug to hit around $2.7 billion this year and $3.3 billion in 2027. Meanwhile, Dupixent grew 26% last year to hit $17.8 billion globally, as reported by Regeneron. Earnings Sanofi defends Dupixent patents, but execs insist it has nothing to do with CEO change Sanofi’s interim leadership sought on a Thursday earnings call to quell concerns that its sudden defense of Dupixent’s patents had anything to do with the departure of CEO Paul Hudson. April 23, 2026 · 3 min read · Annalee Armstrong Read more

Amgen and AstraZeneca’s inflammatory disease drug Tezspire has clinched a phase 3 win in eosinophilic esophagitis (EoE) as the partners eye another challenge to Sanofi and Regeneron’s incumbent Dupixent. A phase 3 EoE trial for Tezspire has hit all primary and key secondary endpoints, Amgen and AZ announced Thursday. By targeting an upstream driver of inflammation, Tezspire demonstrated statistically significant improvements in both histologic remission—defined by a low count of peak eosinophils in the esophagus—and swallowing difficulties compared to placebo at week 24, according to the companies. For both Tezspire doses tested, the treatment effects on the study’s co-primary endpoints lasted through week 52, the companies added. The success from the phase 3 Crossing trial positions the anti-TSLP biologic to potentially expand into its third inflammatory disease indication beyond severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP). Amgen and AZ said they will share the study’s results with regulatory authorities and with the scientific community at an upcoming medical meeting. If approved, Tezspire would open a new front in its rivalry with Dupixent, which became the first medicine specifically indicated for EoE in 2022. Compared with Tezspire’s upstream targeting of TSLP, Dupixent works downstream in the immune cascade by blocking IL-4 and IL-13 signaling pathways. EoE is a chronic inflammatory disease of the esophagus, which can lead to esophageal narrowing and difficulty swallowing, known as dysphagia. The disorder is estimated to affect more than 470,000 people in the U.S., with increased prevalence in the past few years, according to Amgen and AZ. Before biologics are introduced, first-line treatment of EoE typically centers on three methods, frequently referred to as the “3Ds”—drugs, diet and dilation. For drugs, proton pump inhibitors such as omeprazole and swallowed topical corticosteroids like fluticasone are common options. During the Crossing trial, patients were allowed to remain on those background medications. “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,” Arjan Bredenoord, M.D., a gastroenterologist at the Amsterdam University Medical Center in the Netherlands and primary investigator of the Crossing trial, said in an Aug. 27 statement. “The impressive results from the Crossing trial sustained over 52 weeks demonstrate that [Tezspire], 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,” he added. In addition to the primary endpoints measured at week 24 and the key secondary endpoints evaluated at week 52, Crossing also hit other goals, including endoscopic disease features and histologic severity and extent at weeks 24 and 52, plus endoscopic response, inflammatory remission and total endoscopic remission at week 52. Tezspire’s trial win now gives AZ another shot at EoE after its anti-IL5 antibody Fasenra failed to make the cut. Back in 2022, the British pharma reported mixed results from the phase 3 Messina trial, in which Fasenra achieved better histological disease remission compared to placebo but came up short on the dysphagia symptoms metric. Besides EoE, Tezspire is undergoing phase 3 development—the Journey and Embark trials—in chronic obstructive pulmonary disease (COPD). First approved by the FDA for severe asthma in late 2021, Tezspire generated $1.9 billion in combined sales for Amgen and AZ in 2025, up from nearly $1.3 billion the year before. With a much broader label beyond inflammatory conditions affecting the airway, Dupixent brought in $17.8 billion in 2025 global sales. Meanwhile, against the backdrop of Tezspire’s first-in-class wins, drugmakers are developing more anti-TSLP agents. GSK recently launched phase 3 tests of its twice-yearly candidate felcorekibart (GSK5784283) for COPD and asthma after buying the long-acting drug in 2024. Last year, Roche licensed a TSLPxIL-33 bispecific antibody from China’s Qyuns Therapeutics in a deal potentially worth more than $1 billion. Qyuns also out-licensed a TSLPxIL-13 bispecific candidate to Windward Bio, which secured $165 million in crossover financing in May to help advance a twice-yearly anti-TSLP candidate into phase 3. Sanofi is also developing a TSLPxIL-13 bispecific nanobody called lunsekimig, which recently hit goals in a pair of midstage studies for asthma and CRSwNP.