Results from a second phase 3 trial assessing the investigational use of Dupixent (dupilumab) in patients 12 years and older with eosinophilic esophagitis (EoE) demonstrated that the trial met its co-primary endpoints in patients taking Dupixent 300 mg weekly, showing significant improvements in clinical (Dysphagia Symptom Questionnaire) and histologic disease measures compared to placebo.

EoE is a chronic and progressive type 2 inflammatory disease that damages the esophagus and impairs the ability to swallow. In September 2020, the US Food and Drug Administration (FDA) granted Breakthrough Therapy designation to Dupixent for the treatment of patients 12 years and older with EoE.

Results from the extended active treatment period (up to 52 weeks) of a previously reported phase 3 trial studying Dupixent 300 mg weekly for 24 weeks were recently presented at the United European Gastroenterology Week Virtual 2021 congress. Data from the clinical trial program will be submitted to regulatory authorities by 2022.

“The current standard of care for people with eosinophilic esophagitis may only provide limited relief of their symptoms. Efforts to develop a treatment that targets an underlying cause of the disease has eluded the field for some time, resulting in an incredible unmet need,” says Naimish Patel, M.D. head of global development, immunology and inflammation at Sanofi. “We are encouraged that Dupixent, which targets IL-4 and IL-13, was able to reduce inflammation in the esophagus and provided significant relief when swallowing for patients taking the weekly dose. We look forward to continuing to study Dupixent’s potential role in addressing the underlying type 2 inflammation that can lead to eosinophilic esophagitis.”

EoE damages the esophagus and prevents it from working properly. At times, swallowing the smallest quantity of food or taking a sip of water can be a painful and worrisome choking experience. Those with EoE live with anxiety and frustration from having a constantly evolving list of trigger foods to avoid. Dilation (physical expansion) of the esophagus, which is used to address narrowing, is often painful. In severe cases, a feeding tube is the only option to ensure proper caloric intake and weight gain. People with EoE may have poor quality of life and are more likely to experience depression, especially as they age, than people without EoE. In the US, there are approximately 160,000 patients with EoE who are currently treated, of whom approximately 48,000 have failed multiple treatments.

“This trial gives insight into how terrible this disease can be, with more than a third of patients having previously required invasive endoscopic dilations that can temporarily reduce symptoms but carry the risk of rupturing the esophagus,” says George D. Yancopoulos, M.D., Ph.D., president and chief scientific officer at Regeneron. “Dupixent, which blocks the IL-4 and -13 pathways, has now shown compelling results across a spectrum of diseases where there has been great unmet need. In fact, our positive phase 3 data in six different diseases helps confirm our early hypothesis that interleukin-4 and interleukin-13 are the main drivers of allergic or type 2 inflammation and disease, whether manifested in the gastrointestinal tract as eosinophilic esophagitis, the respiratory tract as asthma or nasal polyps, or the skin as atopic dermatitis, chronic spontaneous urticaria, or prurigo nodularis.”

In this trial, 80 patients were enrolled into a Dupixent 300 mg weekly treatment group and 79 patients were enrolled into a placebo group. The co-primary endpoints at 24 weeks assessed patient-reported measures of difficulty swallowing (change from baseline in the Dysphagia Symptom Questionnaire, or DSQ), and esophageal inflammation (proportion of patients achieving peak esophageal intraepithelial eosinophil count of =6 eos/hpf).

Patients treated with Dupixent 300 mg weekly experienced the following changes by week 24 compared to placebo: 64% reduction in disease symptoms from baseline compared to 41% for placebo (p=0.0008). Dupixent patients experienced a 23.78 point improvement on the 0-84 DSQ scale, compared to a 13.86 point improvement for placebo (p<0.0001); baseline DSQ scores were approximately 38 and 36 points, respectively; Nearly 10 times as many Dupixent patients achieved histological disease remission: 59% of patients achieved histological disease remission compared to 6% of placebo patients (p<0.0001). This was measured by the proportion of patients who achieved a peak esophageal intraepithelial eosinophil count of =6 eos/hpf; mean baseline peak levels were 89 and 84 eos/hpf, respectively.

Detailed results from the trial will be shared at an upcoming medical meeting.

The safety results of the trial were generally consistent with the known safety profile of Dupixent in its approved indications. For the 24-week treatment period, overall rates of adverse events were 84% (67/80) for Dupixent 300 mg weekly and 71% (55/78) for placebo. Adverse events that were more commonly (=5%) observed with Dupixent every week included injection site reactions (38% 30/80 Dupixent, 33% 26/78 placebo), fever (6% 5/80 Dupixent, 1% 1/78 placebo), sinusitis (5% 4/80 Dupixent, 0% 0/78 placebo), Covid-19 (5% 4/80 Dupixent, 0% 0/78 placebo) and hypertension (5% 4/80 Dupixent, 1% 1/78 placebo). No imbalance was observed in rates of treatment discontinuation due to adverse events between Dupixent (3% 2/80) and placebo (3% 2/78) groups prior to week 24.

Dupixent was granted Orphan Drug designation for the potential treatment of EoE in 2017. The potential use of Dupixent in EoE is currently under clinical development, and the safety and efficacy have not been fully evaluated by any regulatory authority.