Biological effects and clinical efficacy of a topical Toll-like receptor 7 agonist in seasonal allergic rhinitis: a parallel group controlled phase IIa study.
OBJECTIVE
The purpose of the study was to examine effects of pre-treatment with a Toll-like receptor 7 (TLR7) agonist (AZD8848) in allergic rhinitis and to evaluate clinical effects of two dosing regimens.


METHODS
The study involved 83 patients with allergic rhinitis. Data on effects of AZD8848 on symptoms were analysed with data from a previous study (n = 68) of identical double blind, parallel group design (NCT00770003).


METHODS
The treatment involved intranasal AZD8848 20 µg three times weekly, 60 µg once weekly, or placebo for 5 weeks.


METHODS
Nasal lavage and plasma were analysed for proof-of-mechanism markers. Daily nasal allergen challenges were given for 7 days, starting 24 h after the final AZD8848 dose. Symptoms were monitored after each challenge and every morning and evening.


RESULTS
Markers of TLR-activation increased following AZD8848 administration (CXCL10, TNFα, IL-6, IFNγ). Symptoms recorded soon after allergen challenge were reduced up to eight days after the final dose of AZD8848. Morning and evening symptoms were also reduced, and these changes reached statistical significance for morning observations. Adverse effects were more frequent in the 20 µg three times weekly group.


CONCLUSIONS
Repeated administration of AZD8848 activated TLR7 and produced IFN-induced effects. This was associated with a sustained reduction in allergen responsiveness.
Department of ORL, Head & Neck Surgery, Skåne University Hospital, Getingevägen 4, 221 85, Lund, Sweden. lennart.greiff@skane.se.
Lennart
L
Greiff
Department of ORL, Head & Neck Surgery, Skåne University Hospital, Getingevägen 4, 221 85, Lund, Sweden.
Cecilia
C
Ahlström-Emanuelsson
Research & Development, AstraZeneca, Lund, Sweden.
Mikaela
M
Alenäs
Research & Development, AstraZeneca, Mölndal, Sweden.
Gun
G
Almqvist
Department of ORL, Head & Neck Surgery, Skåne University Hospital, Getingevägen 4, 221 85, Lund, Sweden.
Morgan
M
Andersson
Department of ORL, Helsingborg Hospital, Helsingborg, Sweden.
Anders
A
Cervin
Department of ORL, Helsingborg Hospital, Helsingborg, Sweden.
Jan
J
Dolata
Research & Development, AstraZeneca, Mölndal, Sweden.
Sam
S
Lindgren
Department of ORL, Helsingborg Hospital, Helsingborg, Sweden.
Anders
A
Mårtensson
Research & Development, AstraZeneca, Loughborough, UK.
Barbara
B
Young
Department of ORL, Head & Neck Surgery, Skåne University Hospital, Getingevägen 4, 221 85, Lund, Sweden.
Henrik
H
Widegren
D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D000287:Administration, Topical; D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000276:immunology; D018926:Anti-Allergic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D029662:Betula / Q000276:immunology; D016207:Cytokines / Q000097:blood / Q000276:immunology; D004311:Double-Blind Method; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D017817:Nasal Lavage Fluid / Q000276:immunology; D010648:Phenylacetates / Q000494:pharmacology / Q000627:therapeutic use*; D006109:Poaceae / Q000276:immunology; D011058:Pollen / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000097:blood / Q000188:drug therapy* / Q000276:immunology; D051199:Toll-Like Receptor 7 / Q000819:agonists* / Q000276:immunology; D016896:Treatment Outcome; D055815:Young Adult
C000609563:AZD8848; D000485:Allergens; D018926:Anti-Allergic Agents; D016207:Cytokines; D010648:Phenylacetates; C495348:TLR7 protein, human; D051199:Toll-Like Receptor 7; D000241:Adenosine
Allergen challenge; Biomarkers; CXCL-10; IFNγ; Intranasal TLR7 stimulation; Nasal lavage