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 SHPL49 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 (30-300 mg) and multiple ascending doses (75-300 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) max ) ranging from 673.83 to 6275.00 ng/mL, area under the plasma concentration-time curve (AUC0-t) 0-t ) ranging from 338.57 to 3732.67 h & sdot;ng/mL, and elimination half-life (t1/2) 1/2 ) 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.