Dose Escalation Study of Intravenous Baclofen in Healthy Adult Volunteers

This randomized, open-label, dose escalation, crossover study was conducted at a contract clinical research facility. Three single doses were evaluated using three cohorts (N=12 per cohort). Study doses were as follows: cohort 1 - 7.5mg IV and 10mg PO, cohort 2 - 11.5mg IV and 15mg PO, and cohort 3 - 15mg IV and 20mg PO. The IV baclofen doses for this trial were based on a 75% bioavailability observed in a previous low dose study.16 The oral formulation of the study drug used in this trial was 10mg baclofen tablet (Teva Pharmaceutical Industries Ltd.) and is commercially available. The intravenous formulation was 2mg/mL solution manufactured by Aptuit LLC. for this study. IV infusions were administered over 10 minutes. In addition, cohort 3 received 15mg over a 60-minute infusion. There was a minimum 48-hour washout period between doses. Initially, 3 subjects received study drug at a given dose, after assessing the safety and tolerance of baclofen the additional 9 subjects received study drug.