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

This study in patients with allergic asthma demonstrated that intranasal administration of the TLR7 agonist AZD8848 attenuated the average post-allergen LAR fall in FEV 1 and prevented an increase in AHR following allergen challenge 1 week after the last dose. AZD8848 was generally well tolerated. Currently available asthma therapies, although effective in the majority of patients, do not provide adequate asthma control in a substantial number of patients, require chronic dosing and have potential side effects, particularly at higher doses [31] . TLR7 agonists have potential as a new treatment option for allergic asthma through the stimulation of Th1/Th0 effector cells, thereby attenuating allergen-specific Th2 cells [15, 16] . A potential drawback to this approach has been the systemic induction of proinflammatory cytokines [32] , resulting in influenza-type side effects [33, 34] . To overcome these problems, an antedrug approach has been employed.