In the second quarter of 2018 we announced positive data from our Phase 1 clinical trial of ATYR1923. This first-in-human, randomized, double-blind, placebo-controlled study was designed to investigate the safety, tolerability, immunogenicity and pharmacokinetics of intravenous ATYR1923 in healthy volunteers. The Phase 1 study enrolled 36 healthy volunteers who were randomized to one of six cohorts and received a single infusion of intravenous ATYR1923 or placebo. Doses of ATYR1923 ranged from 0.03 mg/kg up to 5.0 mg/kg. The results indicate that the drug was generally well-tolerated at all dose levels tested, with no significant adverse events or induction of anti-drug antibodies observed following ATYR1923 dosing or throughout the one-month follow-up period.
The pharmacokinetics (PK) of ATYR1923 following single-dose administration were linear across the evaluated dose range. Higher ATYR1923 doses yielded sustained serum concentrations through the end of the one-month follow-up period that were above the predicted therapeutic threshold, supporting the potential for a once-monthly dosing regimen.