Pharmacokinetics, Pharmacodynamics, and Tolerability of Single-Dose Oral LCB01-0371, a Novel Oxazolidinone with Broad-Spectrum Activity, in Healthy Volunteers.

LCB01-0371 is a novel oxazolidinone with broad-spectrum activity against Gram-positive pathogens in both in vitro studies and animal infection models. The objectives of this study were to evaluate its safety, tolerability, pharmacokinetics, and pharmacodynamics following single ascending doses. Single oral doses of 600 mg linezolid, a placebo, or LCB01-0371 of between 50 mg and 3,200 mg were tested in 69 healthy male subjects. Blood and urine were sampled, LCB01-0371 concentrations were measured, and the serum inhibitory and bactericidal titers of LCB01-0371 and linezolid were determined. LCB01-0371 was well tolerated up to 2,400 mg. The most common drug-related clinical and laboratory adverse events were nausea with or without vomiting, decreased neutrophil counts, and increased total bilirubin levels. The frequency of adverse events and drug-related adverse events was similar among the treatment groups. The systemic exposure was approximately dose proportional over the range of 50 mg to 800 mg, which includes the anticipated clinical dose. The mean clearance, renal clearance, and volume of distribution were significantly decreased at higher doses (above 800 mg). LCB01-0371 exhibited early bacteriostatic activity against all tested strains except for Streptococcus pneumoniae strains, and the potency of LCB01-0371 at 800 mg was similar to that of linezolid at the therapeutic dose (600 mg). However, LCB01-0371 had less bactericidal activity than linezolid. Taken together, LCB01-0371 was well tolerated, exhibited approximate dose proportionality within the anticipated clinically relevant dose range, and showed bacteriostatic and bactericidal activity comparable to that of linezolid. These results support the further clinical development of LCB01-0371. (This study has been registered at ClinicalTrials.gov under registration no. NCT01554995.).

Population Pharmacokinetic Model of AST-001, L-Isomer of Serine, Combining Endogenous Production and Exogenous Administration in Healthy Subjects.

AST-001 is an L-isomer of serine that has protective effects on neurological disorders. This study aimed to establish a population pharmacokinetic (PK) model of AST-001 in healthy Korean to further propose a fixed-dose regimen in pediatrics. The model was constructed using 648 plasma concentrations from 24 healthy subjects, including baseline endogenous levels during 24 h and concentrations after a single dose of 10, 20, and 30 g of AST-001. For the simulation, an empirical allometric power model was applied to the apparent clearance and volume of distribution with body weight. The PK characteristics of AST-001 after oral administration were well described by a two-compartment model with zero-order absorption and linear elimination. The endogenous production of AST-001 was well explained by continuous zero-order production at a rate of 0.287 g/h. The simulation results suggested that 2 g, 4 g, 7 g, 10 g, and 14 g twice-daily regimens for the respective groups of 10-14 kg, 15-24 kg, 25-37 kg, 38-51 kg, 52-60 kg were adequate to achieve sufficient exposure to AST-001. The current population PK model well described both observed endogenous production and exogenous administration of AST-001 in healthy subjects. Using the allometric scaling approach, we suggested an optimal fixed-dose regimen with five weight ranges in pediatrics for the upcoming phase 2 trial.

Bioequivalence and tolerability of two clopidogrel salt preparations, besylate and bisulfate: a randomized, open-label, crossover study in healthy Korean male subjects.

BACKGROUND: Clopidogrel, a potent antiplatelet agent, reduces the risk for thrombotic events in patients with atherothrombotic diseases. Clopidogrel is marketed primarily as a bisulfate salt. A different salt preparation of clopidogrel, clopidogrel besylate, has been developed and might provide an additional treatment option for patients. OBJECTIVE: The aim of this study was to compare the pharmacokinetic, pharmacodynamic, and tolerability profiles of clopidogrel besylate with those of clopidogrel bisulfate to determine bioequivalence for the purposes of marketing approval. METHODS: A randomized, open-label, 2-period, single- and multiple-dose, comparative crossover study was conducted in healthy Korean male subjects. The subjects received either clopidogrel bisulfate or clopidogrel besylate as a single 300-mg oral loading dose (day 1) followed by a 75-mg/d (once daily) maintenance dose on days 2 to 6. After a 15-day washout period, subjects were administered the alternative salt preparation according to the same protocol. The plasma concentrations of clopidogrel and its primary metabolite (SR26334) were assessed using high-performance liquid chromatography/tandem mass spectrometry after administration of the loading dose. The platelet aggregation response to 10-mumol/L adenosine diphosphate was measured using turbidometric aggregometry during the single- and multiple-dosing periods and at steady state (day 6). Tolerability was monitored using physical examination, including vital sign measurements, and laboratory analysis. RESULTS: Forty-four subjects were enrolled and completed the study (mean [SD] age, 24.3 [2.7] years; weight, 70.0 [8.2] kg). The mean values for C(max), T(max), and AUC(0-t) with clopidogrel (parent drug) of clopidogrel besylate (5.2 ng/mL, 0.9 hour, and 10.1 ng/mL/h, respectively) were similar to those with clopidogrel bisulfate (5.4 ng/mL, 0.9 hour, and 10.3 ng/mL/h). The mean values for Cmax, AUC(0-t), and AUC(0-infinity) with the SR26334 of clopidogrel besylate (10.9 microg/mL, 38.8 microg/mL/h, and 43.0 microg/mL/h, respectively) were not significantly different from those with the SR26334 of clopidogrel bisulfate (11.9 microg/mL, 40.6 microg/mL/h, and 43.8 microg/mL/h). The mean values for maximal antiplatelet effect (Emax) and area under the time-effect curve (AUEC) with the 2 clopidogrel salt preparations were as follows: clopidogrel besylate, 58.8 h . % and 4299.1 h . % inhibition, respectively; and clopidogrel bisulfate, 61.7 h . % and 4406.9 h . % inhibition; these differences were not statistically significant. The 90% CIs for the ratios of the log-transformed C(max), AUC, E(max), and AUEC values were within the predetermined bioequivalence range of 80% to 125%. Three adverse events (6.8%) were reported during the study and included abdominal discomfort (1 subject [2.3%] in the group that received clopidogrel bisulfate), easy fatigability (1 subject [2.3%] immediately before administration of loading dose of clopidogrel besylate), and thrombocytopenia (1 subject [2.3%] in the group receiving the clopidogrel bisulfate). All adverse events were transient and mild. CONCLUSIONS: In these healthy Korean male subjects, the differences in the pharmacokinetic and pharmacodynamic properties between the 2 clopidogrel salt preparations did not reach statistical significance and met the regulatory requirements for bioequivalence. Both preparations were well tolerated.

Single-dose Intravenous Safety, Tolerability, and Pharmacokinetics and Absolute Bioavailability of LCB01-0371.

PURPOSE: LCB01-0371 is a novel broad-spectrum oxazolidinone antibacterial agent under investigation for the treatment of infection by gram-positive pathogens, including methicillin-resistant Staphylococcus aureus. This study evaluated the safety, tolerability, and pharmacokinetics of LCB01-0371 after a single intravenous (IV) infusion and determined its absolute oral bioavailability at a therapeutic dose of 800 mg. METHODS: This study was conducted in 2 parts. The first part was a single-blind, placebo-controlled, escalating single IV dose study (200, 400, 800, and 1200 mg) of LCB01-0371 via 2 different infusion regimens (250 mL over 60 min or 150 mL over 30 min) in 36 healthy male volunteers. The second part was an open-label, 2-way crossover design study in which 8 subjects were randomly assigned to 1 of 2 sequences of a single oral (800 mg) or IV (400 mg) administration of LCB01-0371. Safety assessments were conducted at regular intervals. Blood and urine were serially sampled, and drug concentrations were measured for up to 24 h to calculate pharmacokinetic parameters. FINDINGS: LCB01-0371 after IV administration was generally safe and well tolerated up to 800 mg regardless of the infusion regimen. Adverse events were mild, excluding nausea at the highest dose, and resolved spontaneously. After a single IV administration, LCB01-0371 exhibited linear pharmacokinetic properties over the range of 200-800 mg. The elimination t1/2, volume of distribution, and clearance ranged from 1.48 to 1.68 h, 57.74-76.72 L, and 33.17-43.31 L/h, respectively, and they remained unchanged over the corresponding dose range. Cmax, AUC0-last, and AUC0-∞ increased in a dose-dependent manner. The dose-normalized total exposure after single PO and IV dosing were equivalent, with 90% CIs of the geometric least squares mean ratio of 86.6%-110% for AUC0-last and 86.6%-111% for AUC0-∞. The dose-normalized Cmax was not equivalent between oral and IV dosing, with a 90% CI of the geometric least squares mean ratio of 50.0%-105%. The absolute oral bioavailability of LCB01-0371 after a single 800-mg dose was 99.75%. IMPLICATIONS: After a single IV administration, LCB01-0371 was well tolerated in healthy volunteers at doses up to 800 mg, and it exhibited linear pharmacokinetic properties. The comparable total systemic exposure between IV and oral administration supports the ability to switch administration routes without a need for dose adjustment. ClinicalTrials.gov identifier: NCT02882789.

Multiple-dose Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Oral LCB01-0371 in Healthy Male Volunteers.

PURPOSE: LCB01-0371 is a novel oxazolidinone broad-spectrum antibacterial that is more potent than linezolid against systemic infections in animals. The goal of this investigation was to evaluate the pharmacokinetics, pharmacodynamics, safety, and tolerability of multiple-dose LCB01-0371 as well as the pharmacokinetic characteristics of a new 400-mg tablet formulation. METHODS: Thirty-two healthy male subjects received BID 400-1600 mg multiple oral dosing of LCB01-0371 (200-mg tablet or 400-mg tablet) for 7 days, and 6 subjects received an 800-mg single oral dose of LCB01-0371 (400-mg tablet). Safety assessments were undertaken at regular intervals. Blood and urine were sampled, and drug concentration and inhibitory and bactericidal titers were measured. FINDINGS: LCB01-0371 was generally safe and well tolerated up to 1200 mg BID for 7 days. Adverse events were mild, except for headache, nausea, and dizziness at the dose of 1600 mg, and resolved spontaneously. LCB01-0371 was absorbed rapidly within 2 h after administration, and its accumulation observed on day 7 ranged between 1.10- and 1.46-fold. The elimination t1/2 was 1.64-1.94 h, which remained unchanged across all doses. AUC0-12 and Cmax were not dose proportional across the dose range from 400 to 1200 mg after both single and multiple dosing, indicating a nonlinear pharmacokinetic profile. The percentage of the dose excreted via the urine ranged from 7.84% to 8.95%. The new (400-mg tablet) formulation exhibited less interindividual variability with pharmacokinetic characteristics similar to the original formulation (200-mg tablet). LCB01-0371 exhibited both early serum inhibitory and bactericidal activities against the 4 strains tested in the ex vivo pharmacodynamics study. IMPLICATIONS: BID doses of LCB01-0371 up to 1200 mg for 7 days were well tolerated and exhibited rapid serum inhibitory and bactericidal activities against common gram-positive pathogens. The results warrant further clinical investigation of the antibacterial effect of BID LCB01-0371 administration. ClinicalTrial.gov identifier: NCT01842516.