Safety, pharmacokinetics and immune effects in normal volunteers of CPG 10101 (ACTILON), an investigational synthetic toll-like receptor 9 agonist.

Unlabelled: CPG 10101 (ACTILON) is a novel potent and selective unmethylated cytidine-phosphate-guanosine (CpG)-containing oligodeoxynucleotide agonist of Toll-like receptor 9 (TLR9) being developed for the treatment of chronic infections such as HCV.

Objectives And Methods: In this randomized, double-blind, placebo-controlled Phase I study in 48 normal volunteers, we investigated the safety, pharmacokinetic parameters and immune effects of subcutaneous administration of CPG 10101. Five sequential escalating doses from 0.

Co-administration of CpG oligonucleotides enhances the late affinity maturation process of human anti-hepatitis B vaccine response.

We assessed the avidity maturation process elicited by human immunization with alum-adsorbed HBsAg alone or with a novel adjuvant containing CpG motifs (CpG 7909). Mean avidity indexes and distribution of low- and high-avidity anti-HBs indicated that avidity maturation essentially takes place late after priming. CpG 7909 markedly enhanced this affinity maturation process, increasing the pool of high-avidity antibodies.

Induction of systemic TH1-like innate immunity in normal volunteers following subcutaneous but not intravenous administration of CPG 7909, a synthetic B-class CpG oligodeoxynucleotide TLR9 agonist.

Subcutaneous injection of normal human volunteers with a B-class CpG oligodeoxynucleotide (ODN) TLR9 agonist, CPG 7909, induced a TH1-like pattern of systemic innate immune activation manifested by expression of IL-6, IL-12p40, IFN-alpha, and IFN-inducible chemokines. Serum IP-10 was found to be the most sensitive assay for subcutaneous CPG 7909 stimulation; its level was significantly increased in all subjects at all dose levels, including the lowest tested dose of just 0.0025 mg/kg.