Effects of the Toll-like receptor 7 (TLR7) agonist, AZD8848, on allergen-induced responses in patients with mild asthma: a double-blind, randomised, parallel-group study

Leaker, Brian R.; Singh, Dave; Lindgren, Sam; Almqvist, Gun; Eriksson, Leif; Young, Barbara; O’Connor, Brian

The allergen-challenge titration procedure performed during the screening period was conducted following the methods of Boulet et al., [25] to establish individually tolerable, repeatable, yet symptom-inducing doses of inhaled allergen [26] . Increasing doses of grass pollen, house dust mite or cat allergens (Aquagen®, Alk-Abello) were administered with a 30 min observation period in between each dose, until an EAR was observed. Following allergen challenge, the patient remained in the clinic for up to 12 h, or overnight if there were any safety concerns, as judged by the Investigator. The cumulative dose of allergen that produced the desired effect of a fall in FEV 1 of at least 20% in each patient was used again for that patient as a single bolus dose in two subsequent challenges, 1 week and 4 weeks after the last dose of treatment.