First-in-human study to assess the safety, tolerability, and pharmacokinetics of intravenous SHPL-49 following single- and multiple-ascending-dose administration in healthy adults

SHPL-49 is an innovative glycoside derivative that is synthesized by structural modifications of salidroside,demonstrating therapeutic effects on animal models of ischemia in pre-clinical experiments. A phase I, single-center, randomized, double-blind, placebo-controlled, single and multiple dose administration study of SHPL-49 was conducted in healthy Chinese volunteers. In single-ascending-dose (SAD) study, 32 subjects randomized 6:2 to receive SHPL-49 (30 mg, 75 mg, 150 mg, 300 mg) or placebo with 30 minutes infusion. In multiple-ascending-dose (MAD) study, subjects were randomized 6:2 to receive SHPL-49 (75 mg, 150 mg, 300 mg) or placebo with 30 minutes infusion every 8 h for 7 days. Safety evaluations were conducted throughout the studies. Plasma and urine concentrations of SHPL-49 were detected and its metabolites were identified. Pharmacokinetic parameters were calculated using noncompartmental methods. SHPL-49 was generally safe and well-tolerated at single ascending doses (30 to 300 mg) and multiple ascending doses (75 to 300 mg). All adverse events were mild and resolved without any intervention. No serious adverse events were reported. In the SAD study, SHPL-49 exhibited dose-proportional plasma pharmacokinetics, with peak plasma concentration (Cmax) ranging from 673.83 to 6275.00 ng/mL, area under the plasma concentration-time curve (AUC0–t) ranging from 338.57 to 3732.67 h·ng/mL, and elimination half-life (t1/2) ranging from 0.49 to 0.67 h. In the MAD, the exposure was also dose-proportional and there was no significant accumulation following multiple dosing. Four metabolites were identified in urine and plasma. SHPL-49 shows a favorable pharmacokinetic, safety, and tolerability profile in healthy Chinese volunteers following a single- and multiple-ascending- dose administration in this study. For future therapeutic investigations, it is recommended to administer SHPL-49 intravenously at 8-hour intervals with a dosage range of 150-300 mg.