To the Fraunhofer Allergen Challenge Chamber by bus, train, or plane – report on a multinational, multicenter clinical trial

Besides the usual German “bitte füllen Sie jetzt Ihren Fragebogen aus”, sentences like “por favor, rellene su cuestionario ahora” and “proszę wypełnić swój kwestionariusz teraz” could be heard when the Fraunhofer ITEM medical staff, supported by interpreters, were asking the participants in a recent clinical trial to complete their questionnaire on how they were feeling.

The test subjects were sitting in an Allergen Challenge Chamber at Fraunhofer ITEM in Hannover, Germany, participating in a multinational, multicenter trial. For this purpose, they had traveled to Hannover by bus, train, or plane from other cities in Germany, Spain, and Poland. It was the first international study of this kind performed at Fraunhofer ITEM – with success.

The aim of this study commissioned to Fraunhofer ITEM was to test the efficacy of different doses of a specific immunotherapy under standardized conditions – conditions which the Fraunhofer Allergen Challenge Chamber is able to provide. Selection of patients and their immunotherapy treatment over five months took place in doctors’ offices and study centers near the patients’ homes. Prior to and after the treatment phases, the patients had to visit the Fraunhofer Allergen Challenge Chamber for efficacy testing of the therapy. To this end, the 172 patients traveled to Hannover by bus, train, or plane, spent the night at a hotel, underwent testing in the challenge chamber for two hours, and then traveled back home.

For over 15 years already, the Fraunhofer Allergen Challenge Chambers have been successfully used to test anti-allergic drugs such as antihistamines, nasal steroids, phytotherapeutics, anticytokine therapeutics, and also specific immunotherapy. Over the years, the Fraunhofer team has gained comprehensive experience – with clinical allergen challenge studies and centralized exposure in challenge chambers within multicenter or even multinational immunotherapy trials. All in all, five challenge chambers for trials with sophisticated study designs are available at Fraunhofer ITEM. Up to 18 test subjects at once can be exposed there to natural pollen, allergen extracts, or ozone. Nasal congestion (rhinomanometry) and the amount of nasal secretions can be measured on the spot. In addition, a state-of-the-art biomarker laboratory allows on-site analysis and evaluation of biomarkers in blood, nasal secretions, and exhaled breath collected during the trials.

The safety and efficacy of anti-allergic treatments can be tested by measuring a broad range of objective and subjective parameters. Another benefit is the small number of patients required to enable significant results – in contrast to field studies, where a larger patient cohort is necessary for reliable results to be obtained. And what is more, studies can be performed all year round, even out of the pollen season. With their standardized conditions, allergen challenge chambers are highly expedient for specific immunotherapy trials, in particular for dose finding and to substantiate the results of field efficacy studies. In fact, a “bad” pollen season with low pollen counts or strong variations may cause failure of an elaborate immunotherapy trial – not because the immunotherapy is ineffective, but because in a bad season, symptoms in patients may be so weak that the therapeutic effect cannot be ascertained.

Patients, staff, and the sponsor were very pleased with the allergen challenge performed in the Fraunhofer Allergen Challenge Chambers. And the test subjects after the trials were bidden farewell with “buena vuelta a casa”, “dobre podróż do domu”, and “gute Heimreise!”