Leading the charge against eosinophilic esophagitis

What is eosinophilic esophagitis?

Eosinophilic esophagitis, or EoE, is a chronic, progressive and debilitating immune-mediated disease of the esophagus triggered by exposure to allergens. In patients with EoE, inflammation of the esophagus leads to difficulty swallowing food, scarring and potentially serious complications. Eosinophils (a type of white blood cell) build up along the lining of the esophagus and give the disease its name.

EoE affects people of every age and is becoming more common with global prevalence increasing rapidly. Approximately 90% of patients with EoE are Caucasian; however, this number may not be representative due to lack of access to healthcare in underserved populations.

The importance of recognition and early diagnosis

Despite rising prevalence, receiving a diagnosis can be burdensome and take years because of lack of awareness of the disease and that signs and symptoms can vary person to person and by age. The clinical presentation of EoE can overlap with other disorders and is often misdiagnosed as gastroesophageal reflux disease (also known as GERD).

Adults may experience difficulty or pain swallowing food, chest pain and heartburn. Children may experience vomiting, complain of belly pain, refuse food or develop an aversion to eating, which can result in failure to thrive (weight loss or poor weight gain). Over time, continued inflammation and scarring can lead to narrowing of the esophagus (stricture), which can cause food to become stuck in the esophagus (impaction), which is a medical emergency.

Symptom duration and diagnostic delay is linked to disease progression, making prompt recognition of the signs of EoE of key importance. An EoE diagnosis is made with an endoscopy (a medical procedure that looks at the esophagus with a tube-like instrument) and a biopsy. These procedures are typically performed by a gastroenterologist and require sedation or anesthesia, a high burden that further contributes to diagnostic delays, particularly in underserved populations.

At Bristol Myers Squibb, we are committed to increasing awareness and understanding of EoE, so we can help address the barriers to diagnosis for all patients.

"Having treated individuals with EoE, I have witnessed the tremendous burden patients experience as a result of this disease," comments Daniel Quirk, MD, MPH, MBA, senior vice president, head of Worldwide Medical Affairs, Immunology and Neuroscience. "Although advances have been made in recent years, a strong unmet need remains to better understand EoE and develop differentiated treatment options."

Navigating life with eosinophilic esophagitis

Dietary restriction is a common treatment for EoE and can be difficult for both patients and their families. Given the intertwined nature of food with social events and activities, needing to avoid certain food, fear of choking, difficulty swallowing food and diet restrictions can cause isolation. Patients may also experience anxiety or stress around eating, develop different accommodating habits (even subconsciously) to alleviate symptoms (avoiding certain textures and foods, chewing very slowly, etc.) and may feel embarrassed enough to avoid social situations altogether.

Over time and as the esophagus progressively narrows from stricture formation, patients can have trouble swallowing food and it can become increasingly difficult to get appropriate nutrition into the body, with some patients relying solely on special formula diets. In serious cases, a procedure called dilation, performed during an endoscopy, is needed to partially re-open the esophagus and allow food to pass.

Addressing the underlying inflammation and fibrosis—and doing so early in the course of the disease—is key to preventing serious complications and improving how patients feel.

The evolving eosinophilic esophagitis treatment landscape

As an immune-mediated disease, it is important to target the underlying inflammatory pathways that are triggering the symptoms and complications of EoE. With this in mind, we are using our knowledge of causal human biology with the goal of discovering and developing new treatments.

Innovation in EoE is particularly challenging given there is still much to learn about the biology of the disease. However, there are numerous studies implicating interleukin-13 (IL-13), a protein involved in cell signaling, in EoE and other allergic diseases where it has been shown to be elevated.  It is important to note:

• IL-13 is a normal part of the human immune response, helping to trigger inflammatory processes that protect the body.
• Excess IL-13 and the signaling pathways it triggers can contribute to allergic inflammation.
• Chronic inflammation can result in fibrosis (tissue damage or scarring).

“Our team is taking a unique, targeted approach to EoE research that focuses on modulating pathways involved in the disease, such as the impact of IL-13 on inflammatory processes,” Daniel observes. “By focusing research efforts in EoE, our goal is to address the underlying drivers of disease and improve the well-being of those impacted by the condition.”     

A look toward the future

We are dedicated to making a meaningful impact on EoE treatment by working to advance patient care. We recently completed a global Phase 3 clinical trial with the goals of both bringing a safe and effective treatment to patients and increasing overall understanding of the disease. Importantly, as part of this work we identified and activated clinical trial sites in racially and ethnically diverse geographies in the United States and are incorporating patients' experiences, perspectives, needs and priorities into our drug development process through our groundbreaking Patient Expert Engagement Resource (PEER) program.