The unique challenges of allergy trials.

From pollen and dust mites to tree nuts and shellfish, the immune system overreactions we call allergies can cause a range of symptoms, from annoying sniffles to life-threatening anaphylaxis.

According to the Center for Disease Control, more than 25% of adults in the US have a seasonal allergy. On top of that, in what Food Allergy Research & Education calls an epidemic, 10% of adults have a food allergy.

Since most aren’t life threatening, we don’t hear as much about allergy research as we do trials for heart disease, cancer, or viruses. But with such a large portion of the population affected by allergies, this area of research remains just as important.

Research Goals

Disease and allergy trials have similarities and differences. They share a goal in the overall improvement of health and quality of life, but follow different blueprints.

• Disease trials often focus on treating or preventing the disease, with goals like reducing symptoms, slowing progression, or finding a cure.
• Allergy trials primarily aim to manage and reduce allergic reactions, improve quality of life, and potentially achieve desensitization or tolerance to allergens.

Allergy Trial Interventions

The intervention or investigational product being studied plays the main role in determining the course of a clinical trial. While diseases can have all sorts of causes that determine how they must be treated, allergies all fall under one umbrella: a reaction of the immune system. This means that one intervention can cover a variety of different allergies. Diseases often require unique treatments, but most allergies can be addressed with antihistamines, decongestants, immunotherapy (allergy shots), or biologics.

Challenges in Allergy Research

Despite their necessity, clinical trials for allergies come with a unique set of challenges due to the complex nature of the conditions. Here are some of the hurdles that researchers need to overcome:

• Finding participants: This is a conflict that much clinical research faces, and allergy trials are no exception. Finding a large group of individuals who have the same allergy, fit specific criteria such as reaction severity, and are willing to join a trial, takes enormous effort and resources.
• Measuring symptoms: Unlike measuring blood pressure or examining a tumor, allergy symptoms like itching, sneezing, and congestion are subjective and may vary. This study on eye-related allergy symptoms notes that there are limits to symptom evaluations, because certain allergy symptoms affect individuals differently. This makes them tricky to compare and assess.
• Strong placebo effect: Allergies are often influenced by psychological factors, making it challenging to distinguish between genuine treatment effects and placebo responses. For example, in studies that evaluate allergic responses in the mouth and throat, treatments commonly cause a placebo effect before they can even take action, simply because that area of the body is very sensitive.
• Assessing data: A major challenge for allergy research is simply the multitude of factors to be assessed. Reactions, symptoms, causes, contributors, and more information must be analyzed as a whole and quantified somehow. As allergy researcher and professor Nikolaos G. Papadopoulos says in this editorial, it’s almost mathematical in nature.

With such a large portion of the population afflicted by allergies, they are a part of many people’s daily lives. Advancing treatments is crucial to addressing severe allergic reactions and can also contribute to improving the everyday person’s quality of life come pollen season. By understanding the unique challenges these trials may present, researchers can design more effective studies and pave the way for advancements in allergy care.

A wide variety of efforts and careful considerations go toward making clinical trials succeed. If you’re looking for support in clinical trial recruitment, let’s connect!