©© 2008 American College of Clinical Pharmacology, Inc.
The Journal of Clinical Pharmacology
, 10.1177/0091270008314466
Cutaneous Pharmacodynamics of a Toll-Like Receptor 7 Agonist, 852A, in Humans
Calvin Astry 1,
Woubalem Birmachu 1,
Lester I. Harrison 1*,
and
Tze-Chiang Meng 1
1 3M Pharmaceuticals
* To whom correspondence should be addressed. E-mail: liharrison{at}mmm.com.
 |
Abstract |
|---|
852A is a specific toll-like receptor 7 (TLR7) agonist. Thirty-two healthy adults (8 subjects per group) received two 1-g topical applications over 400 cm2, separated by
5 days, of 852A 0.01% followed by vehicle, vehicle followed by 852A 0.1%, 852A 0.3% followed by vehicle, or vehicle followed by 852A 1.0%. Systemic absorption was minimal as 852A was not quantifiable in any serum sample up to 24 hours postadministration and was only quantifiable at 24 hours in the urine of 4 of 8 subjects after application of 852A 1.0%. No systemic adverse events were associated with drug treatment. Gene expression analysis from application site biopsies showed a
2-fold increase in expression for 40 genes in at least 2 subjects. CXCL9/MIG (8/32 subjects), CCL2/MCP1 (7/32), and OAS3 (5/32) were most frequently increased, followed by other type I interferon-inducible genes. Cluster analysis of the genes with a
2-fold increase did not reveal a definitive pattern with respect to 852A concentration or time of biopsy. Overall, single topical application of 852A up to 1.0% was well tolerated. Data gathered from these subjects are suggestive that 852A can produce increases in local gene expression consistent with TLR7 stimulation.