Synthesis and radioprotective effects of novel hybrid compounds containing edaravone analogue and 3-n-butylphthalide ring-opening derivatives.

As the potential risk of radiation exposure is increasing, radioprotectors studies are gaining importance. In this study, novel hybrid compounds containing edaravone analogue and 3-n-butylphthalide ring-opening derivatives were synthesized, and their radioprotective effects were evaluated. Among these, compound 10a displayed the highest radioprotective activity in IEC-6 and HFL-1 cells. Its oral administration increased the survival rates of irradiated mice and alleviated total body irradiation (TBI)-induced hematopoietic damage by mitigating myelosuppression and improving hematopoietic stem/progenitor cell frequencies. Furthermore, 10a treatment prevented abdominal irradiation (ABI)-induced structural damage to the small intestine. Experiment results demonstrated that 10a increased the number of Lgr5+ intestinal stem cells, lysozyme+ Paneth cells and Ki67+ transient amplifying cells, and reduced apoptosis of the intestinal epithelium cells in irradiated mice. Moreover, in vitro and in vivo studies demonstrated that the radioprotective activity of 10a is associated to the reduction of oxidative stress and the inhibition of DNA damage. Furthermore, compound 10a downregulated the expressions of p53, Bax, caspase-9 and caspase-3, and upregulated the expression of Bcl-2, suggesting that it could prevent irradiation-induced intestinal damage through the p53-dependent apoptotic pathway. Collectively, these findings demonstrate that 10a is beneficial for the prevention of radiation damage and has the potential to be a radioprotector.

A Randomized, Single-Blind, Placebo-Controlled, 3-Way Crossover Study to Evaluate the Effect of Therapeutic and Supratherapeutic Doses of Edaravone on QT/QTc Interval in Healthy Subjects.

This randomized, single-blind, 3-way crossover study assessed the effect of edaravone on QT interval, including an exposure-response analysis. Twenty-seven healthy Japanese male volunteers, aged 20 to 49 years, were randomly assigned to receive a single intravenous dose of each treatment in 1 of 3 sequences (n = 9 each): ACB, BAC, and CBA, where A was edaravone 60 mg (therapeutic dose), B was edaravone 300 mg (supratherapeutic dose), and C was normal saline (placebo). Electrocardiographs were collected to assess treatment effects. In an exposure-response analysis, a linear model was determined to be valid and indicated no statistically significant positive slope for the relationship between change from baseline in QTcF (ΔQTcF) and edaravone concentration (0.000155 ms/(ng/mL); P = .1478); upper bounds of 2-sided 90% confidence intervals after placebo adjustment (ΔΔQTcF) were <10 milliseconds at the geometric mean maximum concentration for each edaravone dose. Overall estimated values by time point of ΔΔQTcF ≤0.9 milliseconds, no outlier values, and no morphologic changes suggestive of repolarization abnormalities were observed. Analysis of heart rate, PR interval, and QRS duration also revealed no adverse findings. These data indicate that edaravone, even at supratherapeutic doses, does not produce clinically meaningful QT prolongation and has no clinically relevant cardiac effects.

Open-label, Single-dose Studies of the Pharmacokinetics of Edaravone in Subjects with Mild, Moderate, or Severe Hepatic Impairment Compared to Subjects with Normal Hepatic Functioning.

PURPOSE: Two studies were conducted to assess the pharmacokinetic (PK) properties and tolerability of edaravone in Japanese subjects with mild to moderate hepatic impairment or normal hepatic functioning (study 1), and in white subjects with severe hepatic impairment compared to subjects with normal hepatic functioning (study 2). METHODS: Studies 1 and 2 were multicenter, open-label, single-dose studies that included subjects aged 18-75 years. In study 1, subjects were stratified into 3 different groups of hepatic functioning according to Child-Pugh score: mild hepatic impairment, score 5 or 6 (n = 8); moderate hepatic impairment, score 7-9 (n = 6); or normal hepatic functioning (n = 8). In study 2, subjects had severe hepatic impairment (Child-Pugh score 10-14; n = 6) or normal hepatic functioning (n = 6). In both studies, all subjects were given edaravone 30 mg IV infused over 60 min on the morning of day 1. Blood samples for use in PK analyses were collected from days 1-3. The PK properties (Cmax, AUC0-last, and AUC0-∞) of edaravone and its sulfate conjugate metabolite were measured. FINDINGS: In study 1, the geometric least-squares mean (GLSM) Cmax and AUC0-∞ of unchanged edaravone were 1.203- and 1.065-fold greater, respectively, in subjects with mild hepatic impairment versus normal hepatic functioning, and were 1.235- and 1.142-fold greater, respectively, in subjects with moderate hepatic impairment versus normal hepatic functioning. In study 2, GLSM Cmax and AUC0-∞ of unchanged edaravone were 1.203- and 1.190-fold greater, respectively, in subjects with severe hepatic impairment versus normal hepatic functioning. In both studies the AUC0-last, AUC0-∞, unbound AUC from time zero to infinity, and Cmax of unchanged edaravone were increased slightly with increases in Child-Pugh classification. No adverse events considered related to edaravone were reported, except for 1 case of sinus bradycardia in a subject with normal hepatic functioning in study 2. The event was moderate in severity, considered as possibly related to edaravone, and resolved during the study. IMPLICATIONS: Mild to moderate and severe hepatic impairment had no apparent clinically significant effects on the PK profile of edaravone in Japanese and white subjects, respectively, relative to individuals with normal hepatic functioning, and there were no notable tolerability concerns. Thus, edaravone dosage adjustments are unlikely to be needed in edaravone-treated patients with mild to moderate and severe hepatic impairment. ClinicalTrials.gov identifiers: NCT03289234 (mild to moderate hepatic impairment) and NCT03664544 (severe hepatic impairment).

Two high-performance liquid chromatography-tandem mass spectrometry methods for determination of edaravone and taurine in human plasma: Application to drug-drug interaction and pharmacokinetic studies.

Two high-performance liquid chromatography-tandem mass spectrometry methods were developed and validated for the quantification of edaravone (method A) or taurine (method B) in human plasma. After protein precipitation, separations were achieved on an Ultimate XB-C8 (2.1 × 50 mm, 3.0 µm) column for edaravone and a ZORBAX SB-Aq column (2.1 × 100 mm, 3.5 µm) for taurine, respectively. The detection used electrospray ionization source via multiple reaction monitoring in positive-ion mode for edaravone and negative-ion mode for taurine, respectively. The lower limits of quantification were 10.0 ng/mL for edaravone and 3.00 µg/mL for taurine. The selectivity, accuracy, and precision of the methods were all within acceptable limits. Two methods were successfully applied to a drug-drug interaction study and a pharmacokinetic study of edaravone and taurine in healthy Chinese volunteers after intravenous infusion of single or compound injection. The results showed that co-administration of edaravone with taurine increased the Cmax and AUC0-24 of taurine in human plasma while taurine did not affect the systemic exposure of edaravone. Edaravone and taurine have the dose-dependent pharmacokinetic profiles in human.

Predicting the Pharmacokinetic Characteristics of Edaravone Intravenous Injection and Sublingual Tablet Through Modeling and Simulation.

PURPOSE: Edaravone is a free-radical scavenger with relatively favorable properties of brain penetration. It has been approved for the indications of acute ischemic stroke and amyotrophic lateral sclerosis (ALS). This study aimed to establish a pharmacokinetic (PK) model to fit the PK profile of edaravone after a single sublingual (SL) dose of a novel edaravone tablet and single IV infusion of injectable edaravone in healthy Chinese volunteers participating in a bioavailability study. The model is expected to be useful for predicting the concentration-time profiles of edaravone following different dosing regimens in a healthy Chinese population. The purposes were to identify an optimal dose and dosing regimen for the new SL formulation and to support future clinical exploration of this tablet product in its approved indications and other therapeutic fields being developed. METHODS: The PK profiles after a single SL dose or IV infusion of edaravone 30 mg can be well described by a 3-compartment linear disposition model, on which a first-order absorption model with a lag time and a parameter for bioavailability was incorporated to fit the absorption phase of the SL dose. Performance of these PK models was evaluated for goodness of fit, residual trends, visual predictive checks, as well as precision of model predictions against external data. The validated models were employed for simulating the PK profiles of edaravone after a single SL dose of 60 mg and IV infusion of 60 mg for 60 min. FINDINGS: The resultant estimates support the possibility and feasibility of demonstrating bioequivalence between an SL administration of edaravone 60 mg and the currently approved dosing regimen for ALS (ie, 60 mg IV over 60 min) once per day. The calculation of sample size suggested that the requirement for subject number was acceptable considering the general capacity of a Phase I study center, and so were the procedures defined in the protocol. IMPLICATION: The models can be further applied to simulate favorable concentration-time profiles in diseases with different underlying courses of oxidative stress, and hence facilitate the optimization of current dosing regimens.