药代动力学

ORIGINAL RESEARCH ARTICLE

Multiple Dose Pharmacokinetics and Safety of Sulcardine Sulfate in Healthy Chinese Male Subjects:An Open-Label Phase I Clinical Study

Wei Wang 1?Hong-jie Qian 2?Liang Xin 2?Meng-qi Zhang 2?Dong-ying Lu 4?

Jie-mei Jin 2?Gang-yi Liu 2?Jing-ying Jia 2?Hong-chao Zheng 3?Chen Yu 2?Yi-ping Wang 4?Fu Zhu 3?Yun Liu 2

óSpringer International Publishing Switzerland 2016

Abstract

Background Sulcardine sulfate is a novel antiarrhythmic agent with mechanism of action as a multi-ion channel blocker.Preclinical studies in animal models have demonstrated that sulcardine sulfate is ef?cacious in atrial and ventricular arrhythmias,and consequently,leads to the prevention of sudden cardiac death.

Objectives This study was conducted in healthy Chinese male subjects to investigate the pharmacokinetic pro?le and safety of sulcardine sulfate after repeated oral dose administration at 200,400,and 800mg for 5days.

Methods Thirty-three male subjects were enrolled in this study.In the multiple dose phase,sulcardine sulfate was administered orally twice at the interval of q12h since day 3.Sulcardine sulfate plasma concentration was determined using a validated LC–MS/MS method.Safety was assessed using clinical evaluation and AE monitoring.

Results In this repeated dose study,pharmacokinetic parameters (C max ,AUC (0–t ),and C ss_av)increased with the increase in dose (the dose ratio of the three cohorts was 1:2:4,while the ratio of C max and AUC (0–t )at day 1was around 1:4:9and 1:4:6,respectively),but in a non-linear fashion.The accumulation ratio at steady state (AR)of 200,400,and 800mg dose level was 1.18,1.69,and 2.13,respectively,indicating that sulcardine sulfate has a modest accumulation upon repeated dose administration.Moni-toring of pre-dose plasma concentrations on days 6,7,and 8for each dose level indicated that steady state was achieved at day 6after three-day repeated dosing.

Conclusions Pharmacokinetic characteristics of sulcardine sulfate were shown to be non-linear,with the modest accumulation upon repeated dosing,and sulcardine sulfate was safe and well tolerated.

Key Points

The pharmacokinetic characteristics of sulcardine sulfate were non-linear.

Sulcardine sulfate was shown to have modest accumulation upon repeated dosing.

Sulcardine sulfate was well tolerated in healthy Chinese male subjects.

&Fu Zhu

zhufu@https://www.360docs.net/doc/2c9135894.html, &Yun Liu

yliu@https://www.360docs.net/doc/2c9135894.html,

1

Emergency Ward,Shanghai Xuhui Central Hospital and Zhongshan-Xuhui Hospital,Fudan University and Shanghai Clinical Center,Chinese Academy of Science,Shanghai,China

2

Department of Cardiology,Shanghai Xuhui Central Hospital and Zhongshan-Xuhui Hospital,Fudan University and Shanghai Clinical Center,Chinese Academy of Science,Shanghai,China

3

Department of Cardiology,Shanghai Xuhui Central Hospital and Zhongshan-Xuhui Hospital,Fudan University and Shanghai Clinical Center,Chinese Academy of Science,Shanghai,China

4

Department of Pharmacology,State Key Laboratory of Drug Research,Shanghai Institute of Materia Medica,Chinese Academy of Sciences,Shanghai,China

Eur J Drug Metab Pharmacokinet DOI 10.1007/s13318-016-0370-1

1Introduction

Arrhythmia is a common clinical abnormality,induced by not only several cardiovascular diseases,such as coronary heart disease,hypertension,and myocarditis[1],but also certain medications[2,3].Antiarrhythmic medications have been used to treat arrhythmia since several decades ago,and new treatments are being developed continuously [4].

Sulcardine sulfate is a novel antiarrhythmic agent that is currently in clinical trials as a potential treatment for atrial ?brillation and ventricular arrhythmias.Sulcardine sulfate exerts blocking effects on sodium,potassium,and calcium ion channels.Sulcardine sulfate does not induce early after-depolarizations or other electrophysiological abnormalities [5].In animal studies against aconitine-induced arrhyth-mias in rats and ouabain-induced arrhythmias in guinea pigs,sulcardine sulfate was demonstrated to have potent ef?cacy in anti-atrial?brillation and anti-ventricular tachycardia as a multi-ion channel blocker[6].Moreover, sulcardine sulfate has been shown to suppress ventricular arrhythmias in the conscious canine model of sudden car-diac death and to prevent the development of ventricular ?brillation in response to an acute ischemic event at a site distant from an area of previous myocardial infarction.The antiarrhythmic actions of sulcardine sulfate make the experimental drug a potential candidate for continued studies in humans to determine its ef?cacy in treating atrial and ventricular arrhythmias and preventing secondary sudden cardiac death[7,8].

In a single-dose Phase I study,ten healthy subjects were enrolled in cohorts A,B,C,and D(sulcardine sulfate doses of200,400,and800mg under fasting condition and400mg post-meal)in a crossover design. Sulcardine sulfate was shown to be safe and well toler-ated in healthy Chinese subjects.Pharmacokinetic pro?le demonstrated that maximum plasma concentration C max and area under the plasma concentration-time curve (AUC)from time zero to the last quanti?able time AUC(0–t)increased correspondingly with the dose increasing of sulcardine sulfate.There was no signi?cant differences in time to reach C max(T max)and terminal elimination half-life(t1/2)among cohorts A,B,and C (P[0.05).No signi?cant difference was identi?ed between male and female in main pharmacokinetic parameters other than t1/2.Furthermore,no food effect was observed on the absorption and bioavailability of sulcardine sulfate(P[0.05)(Data on?le).

The current open-label,multiple dose Phase I study was designed to investigate the pharmacokinetic pro?le and safety of sulcardine sulfate in healthy Chinese male sub-jects after repeated dose of200,400,and800mg.2Subjects and Methods

2.1Study Design and Population

This was an open-label,multiple dose study in healthy Chinese subjects,conducted at a single center.The study protocol was approved by an independent ethics commit-tee,and the study was conducted in accordance with the guidelines for Good Clinical Practice recommended by the Chinese Food and Drug Administration[9]and with the ethical standards for human experimentation established in the Declaration of Helsinki[10].All subjects provided written informed consent prior to start of study-related procedures.

Subjects who met the following inclusion criteria,while did not meet the exclusion criteria,were eligible to par-ticipate in the study.Inclusion criteria are:(1)male subject between18and45years of age;(2)subject with a body mass index(BMI)between19and24kg/m2(included);(3) no medical history of heart,liver,renal,digestive tract,and hematological system;(4)no allergy history;and(5)in good health as determined by the investigator on the basis of vital signs,physical examination,12-lead ECG,and results of laboratory tests during Screening.Exclusion criteria are:(1)having a history of tumor,orthostatic hypotension,or psychosis;(2)positive hepatitis B virus surface antigen or hepatitis C virus antibody;positive HIV test result;(3)use of any drug(except for acetaminophen) within2weeks prior to screening;(4)participation in any clinical trial within3months;(5)blood donation within 3months;(6)heart rate\45,or[100beat/min;systolic BP[140mmHg,or diastolic BP[90mmHg;and(7) using drugs or alcohol in excess.

Based on the results of previous Phase I tolerability study and single-dose pharmacokinetic study of sulcardine sulfate,the dose level of this multiple dose study was selected as200,400,and800mg.This study was designed with three cohorts(Cohort A200mg,Cohort B400mg, and Cohort C800mg).Since no signi?cant difference was observed in C max and AUC between male and female in previous single-dose study of sulcardine sulfate,only male healthy subjects were included for this multiple dose study. According to the SFDA(State Food and Drug Adminis-tration of China)Technical Guidance for Clinical Phar-macokinetics Research on Chemical Drug(2005),the recommended sample size is8–12subjects for each dose level[11].Therefore,11male subjects were enrolled in each of the three cohorts,33subjects in total.Based on the result of t1/2(around17h)in the single-dose study,the administration interval of sulcardine sulfate was deter-mined every12h(twice daily)for the multiple dose study. The?ow chart of dosing sequence is demonstrated in

W.Wang et al.

Fig.1.Eligible subjects were admitted to the Phase I unit one day before drug administration.Sulcardine sulfate was 200mg per tablet,thus two tablets would be administered for 400mg,while four tablets for 800mg.In the morning of day 1,subjects received sulcardine sulfate at the respective dose levels orally after an overnight fast of 12h,and water deprivation of 2h.Starting from day 3,subjects began to take sulcardine sulfate orally at the respective dose levels at the interval of q12h.The morning dose at day 8was the last dose for multiple dose phase.All doses were administered with 200mL of water.Cigarette,alco-hol,tea,and beverage containing caffeine were prohibited during the entire study.

2.2Pharmacokinetic Assessments

Approximately 2mL of venous blood was collected via an indwelling cannula at each time point.At day 1,blood samples were collected at pre-dose and post-dose at 0.25,0.5,0.75,1,1.25,1.5,2,3,4,6,8,12,24,and 48h,15collection points in total.During the multiple dose phase,blood samples were collected twice a day pre-dose from day 6(but only prior to morning dose for cohort C),to monitor whether steady state has been reached.On day 8,blood samples were collected at pre-dose and post-dose at 0.25,0.5,0.75,1,1.25,1.5,2,3,4,6,8,12,24,and 48h.The collected blood samples were centrifuged at 3000r/min for 10min at 4°C within 30min to obtain plasma.Sulcardine sulfate plasma concentrations were deter-mined using a validated liquid chromatography and tandem mass spectrometery (LC-MS/MS)method.D4-sulcardine sulfate was chosen as the internal standard.The calibration curve was linear over the concentration range from 5.0to 1000ng/mL,resulting in a correlation coef?cient r [0.9983.The intra-and inter-batch precisions of sul-cardine sulfate ranged from 2.4to 9.2%and from 3.8to 10.5%.The intra-and inter-batch accuracies of sulcardine

sulfate ranged from 93.1to 103.9%and from 84.9to 107.3%[12].

Pharmacokinetic parameters were analyzed by non-compartmental models using the DAS 2.0software (DAS 2.0software was purchased from University of Science and Technology,Hefei,China).Plasma pharmacokinetic parameters included area under the concentration–time curve (AUC),maximum observed plasma concentration (C max ),time to maximum plasma concentration (T max ),terminal elimination half-life (t 1/2),and mean residence time (MRT (0–t )).AUC from time zero (pre-dose)to the time of the last measurable concentration (AUC (0–t ))and AUC from time zero (pre-dose)to in?nite time (AUC (0–?))were calculated using a combination of linear (before T max )and logarithmic (after T max )trapezoidal methods.For sin-gle-dose administration only,AUC (0–?)was calculated as AUC (0–t )?C t /k z ,where t is the time of last quanti?able concentration,C t is the last quanti?able concentration,and k z is the terminal plasma elimination rate-constant.For multiple dose administration,AUC at steady state (AUC ss ),maximum and minimum plasma concentration at steady state (C ss_max ,C ss_min )were assessed.Average plasma concentration at steady state (C ss_av )was calculated as AUC ss(0–s )/s ,where s is the dosing interval.Degree of ?uctuation (DF)was calculated as [(C ss_max -C ss_min )/C ss_av ]9100%to determine the ?uctuation of plasma concentration at steady state.Accumulation ratio at steady state (AR)was calculated as (AUC ss(0–s ),day 8)/(AUC (0–?),day 1).

2.3Safety and Tolerability Assessments

Tolerability was assessed using physical examination,vital sign measurements (including body temperature,blood pressure,heart rate,and breathing rate),12-lead ECG,echocardiogram,and laboratory measurements (including hematology,serum chemistry,thyroid function test,and urinalysis).Assessment was conducted before ?rst dose,days 3–7after ?rst dose,as well as 48h after last dose (the time point differed for different measurements and cohorts).Adverse events (AEs)were monitored throughout the study.Adverse event was de?ned as any unfavourable and unintended sign (including an abnormal laboratory ?nding),symptom,or disease,whether or not related to the use of sulcardine sulfate.All AEs were recorded and evaluated by investigators in terms of severity (mild,moderate,or severe),duration,seriousness,outcome,and relationship to study drug.2.4Statistical Analyses

Statistical analysis was performed using the SAS version 8.0(SAS Institute Inc,Cary,North Carolina).Baseline

and

Fig.1Flow chart of sulcardine sulfate (Sul)dosing sequence.N number of subjects,Bid twice daily,PK pharmacokinetic

Multiple Dose Pharmacokinetics and Safety of Sulcardine Sulfate

demographic characteristics,safety data,and pharmacoki-netic parameters of sulcardine sulfate were summarized using descriptive statistics.AEs are summarized by fre-quencies and percentages.ANOVA was used to compare the sulcardine sulfate pre-dose plasma concentration among days6,7,and8.A value of P\0.05was consid-ered statistically signi?cant,and P\0.01was remarkably signi?cant.

3Results

3.1Demographics of the Study Population

Thirty-three healthy Chinese male subjects,11subjects in cohorts A,B,and C,respectively,were enrolled in this study.All33subjects completed the study per protocol. The demographics of enrolled subjects in the three cohorts are demonstrated in Table1.

3.2Pharmacokinetic Properties

The main pharmacokinetic parameters of sulcardine sulfate administered at200,400,and800mg during single-dose phase(day1)are presented in Table2.The corresponding arithmetic mean(SD)sulcardine sulfate plasma concen-tration–time pro?les at day1are displayed in Fig.2.The dose ratio of the three cohorts was1:2:4,while the ratio of C max and AUC(0–t)at day1was around1:4:9and1:4:6, respectively.Especially at the lower dose range (200–400mg),the exposure increased more than propor-tionally(49)as the dose doubles.R2of linear regression analysis[log e transformed C max and AUC(0–t)to log e transformed dose]was0.6123and0.6115,suggesting that the exposure increased in a non-linear fashion with increase in https://www.360docs.net/doc/2c9135894.html,ing con?dence interval criteria to assess the dose proportionality displayed that the linearity of sulcardine sulfate could not be decided within 200–800mg.

Main pharmacokinetic parameters of sulcardine sulfate administered at200,400,and800mg during multiple dose phase(day8)are presented in Table3.The corresponding arithmetic mean(SD)sulcardine sulfate plasma concentration–time pro?les at day8are displayed in Fig.3. The accumulation ratio at steady state(AR)of200,400, and800mg dose level was1.18,1.69,and2.13,respec-tively,indicating that sulcardine sulfate has a modest accumulation upon repeated dosing,and the accumulation is more profound at higher dose level.At steady state,the ratio of average concentration(C ss_av)for the three dose cohorts was1:5:9,again con?rming non-linear pharma-cokinetics of sulcardine sulfate within200–800mg(R square of linear regression analysis[log e transformed C ss_av to log e transformed dose]was0.7436).

Table4demonstrates the sulcardine sulfate plasma concentration of days6,7,and8pre-dose at200,400,and 800mg.There was no signi?cant ascending trend of C min from day6to day8.No signi?cant difference was found among plasma concentration of different time points for each dose level(P[0.05),which indicated that steady state was achieved at day6after three-day repeated dosing.

3.3Safety and Tolerability

For safety parameters(vital signs,12-lead ECG,ejection fraction in echocardiogram),no clinically signi?cant changes were observed among the33subjects after?ve-day repeated dosing.All AEs observed during the entire study are listed in Table5.The most frequently reported AE was the increase of triglyceride,occurring in?ve subjects(15.2%).The increase of total bilirubin and dizziness took second place,occurring in three subjects (9.1%),respectively.AEs were recovered before study was over,or were followed up until recovery after study was over.No deaths or serious AEs were reported throughout the study.

4Discussion

This open-label,multiple dose Phase I study was aimed to investigate the pharmacokinetic pro?le and safety of sul-cardine sulfate in healthy Chinese subjects after repeated dose of200,400,and800mg.Previously,mean t1/2was reported to be17h from a single-dose study at200,400, and800mg dose levels,thus the dosing interval was

Table1Demographics of enrolled subjects in cohorts A, B,and C Demographics Cohort A(n=11)Cohort B(n=11)Cohort C(n=11)

Age(years)22.8(2.3)22.4(1.9)25.3(2.9)

Height(cm)171(6.7)172(3.0)169(4.9) Weight(kg)61(7.8)61(3.0)59(4.7)

BMI(kg/m2)20.8(2.0)20.5(1.1)20.6(1.4)

Data are expressed as arithmetic mean(SD)

BMI body mass index,SD standard deviation

W.Wang et al.

determined as every 12h (twice daily)for the current multiple dose study.

In the previous single-dose Phase I study at 200,400,and 800mg,the ratios of C max and AUC (0–t )were 1:2.78:7.74and 1:2.39:6.22,suggesting that C max and

AUC (0–t )increased in a manner that was slightly more than proportional to the dose increase from 200to 800mg.While in this multiple dose study,pharmacokinetic parameters C max and AUC (0–t )during single-dose phase (day 1),as well as C ss_av after repeated dosing (day 8)increased in a non-linear fashion with increase in dose and the increase was more than proportional at lower dose range,which was consistent with the result of the previous single-dose study.This indicates a non-linear elimination of sulcardine sulfate.It is supposed that saturation may exist in the elimination phase,causing by the saturation of metabolic enzyme or transporters during elimination phase.As for the more than proportional increase at lower dose range,one hypothesis is that there are two metabolic or elimination pathways for sulcardine sulfate,one operates at the entire dose range with limited capacity,and the other operates only at the higher dose range (high Km enzyme).Due to the observed non-liner pharmacokinetics,we sug-gest to add 300mg dose level in deciding the Phase II

Table 2Main pharmacokinetic parameters of sulcardine sulfate administered at 200,400,and 800mg during single-dose phase (day 1)

Pharmacokinetic parameters 200mg (n =11)400mg (n =11)800mg (n =11)C max (ng/mL)106.7(66.31)

410.1(223.17)

904(567)T max (h)3(0.75–4)3(0.75–4)2(0.5–4)MRT (0–t )(h)11.2(5.09)11.16(1.22)9.59(1.48)t 1/2(h)

22.41(18.33)14.02(4.93)14.87(7.22)AUC (0–t )(ng áh/mL)558.6(389.2)2310(1225.64)3595(1843)AUC (0–?)(ng áh/mL)

772.1(551.7)

2486(1336.94)

3806(1811)

Data are expressed as arithmetic mean (SD),except for T max which is expressed as median (range)C max maximum observed plasma concentration,T max time to maximum plasma concentration,MRT (0–t)mean residence time,t 1/2terminal elimination half-life,AUC (0–t)area under the concentration–time curve from time zero to the time of the last measurable concentration,AUC (0–?)AUC from time zero to in?nite

time

Fig.2Arithmetic mean (SD)sulcardine sulfate plasma concentra-tion–time pro?les of 200,400,and 800mg during single-dose phase (day 1)

Table 3Main pharmacokinetic parameters of sulcardine sulfate administered at 200,400,and 800mg during multiple dose phase (day 8)

Pharmacokinetic parameters 200mg (n =11)400mg (n =11)800mg (n =11)C max (ng/mL)222.7(180.2)

693.6(231.9)

1616(904)

T max (h)3(1-6)2(1-4)2(1.25–6)MRT (0–t )(h)15.75(1.85)12.72(1.19)10.55(0.95)t 1/2(h)

19.24(12.09)12.51(4.71)10.59(2.64)AUC (0–t )(ng áh/mL)1870(970.4)7411(3640)12,178(6442)AUC (0–?)(ng áh/mL)2292(1449)8094(4417)12,644(6610)AUC ss (ng áh/mL)914.7(512.9)4212(1761)8111(4343)C ss_min (ng/mL)36.37(21.76)149.5(86.38)236(147)C ss_av (ng/mL)76.23(42.75)351.0(146.8)676(362)DF (%)

2.479(1.29)

1.614(0.45)

2.07(0.51)

Data are expressed as arithmetic mean (SD),except for T max which is expressed as median (range)

C max maximum observed plasma concentration,T max time to maximum plasma concentration,MRT (0–t)mean residence time,t 1/2terminal elimination half-life,AUC (0–t)AUC from time zero to the time of the last measurable concentration,AUC (0–?)AUC from time zero to in?nite time,AUC ss AUC at steady state,C ss_min minimum plasma concentration at steady state,C ss_av average plasma concentration at steady state,DF degree of ?uctuation

Multiple Dose Pharmacokinetics and Safety of Sulcardine Sulfate

recommended dose (P2RD).A modest accumulation upon a repeated dosing was observed in the study (AR was 1.18,1.69,and 2.13,respectively),which was aggregated at higher dose levels.Regarding further application of sul-cardine sulfate on patients with liver or renal impairments,and for elderly patients,it is recommended to conduct additional pharmacokinetic studies in these special populations.

The steady state was achieved at Day 6after three-day repeated dosing.For the three cohorts,mean C max of day 8was 1.8-2.1times as much as that of day 1,while T max of day 8was as the same as that of day 1.Previously,an

experiment of high-dose sulcardine sulfate was conducted on rhesus monkeys prior to the current multiple dose study in human subjects,to observe the acute toxicity in high-dose level.The acute toxicity concentration was proved to be 20mg/L in rhesus monkeys [Data on ?le].In this multiple dose study in healthy subjects,the mean C max at 800mg dose level at day 8after ?ve-day repeated dose was 1.616±0.904mg/L,which was approximately 1/10of the acute toxic concentration observed on rhesus monkeys.It is assumed that after repeated dosing of sulcardine sulfate at 800mg,there is still a tenfold safety window and,there-fore,clinical toxicity is unlikely.

Sulcardine sulfate was well tolerated by healthy male subjects in the current study.All AEs were of mild intensity and recovered spontaneously without interven-tion.The most frequently observed laboratory abnormal-ities were the increase of total bilirubin and triglyceride.The abnormality was followed up,and was recovered afterward.

Sulcardine sulfate is a novel antiarrhythmic agent which is currently under Phase II clinical study.The contribution of this multiple dose Phase I study in healthy subjects is to provide much information on pharmacokinetics and safety for Phase II study.Due to the observed non-liner phar-macokinetics of sulcardine sulfate,300mg dose level is suggested in deciding the Phase II recommended dose.For safety reason,clinical investigators should pay

more

Fig.3Arithmetic mean (SD)sulcardine sulfate plasma concentra-tion–time pro?les of 200,400,and 800mg during multiple dose phase (day 8)

Table 4Mean minimum plasma concentration of

sulcardine sulfate on days 6,7,and 8pre-dose at 200,400,and 800mg

Dose (mg)Day 6Day 7Day 8P value

8:00

20:008:0020:008:0020040.6(25)34.8(18)38.4(25)40.5(26)36.4(22)0.9710400128(93)160(105)145(94)173(112)149(86)0.8674800

233(129)

–

267(188)

–

236(147)

0.8597

Data are expressed as arithmetic mean (SD)The concentration unit is ng/mL

Table 5All adverse events (AEs)observed during the entire study

AE

Total n (%)Cohort A n Cohort B n Cohort C n Increase of total bilirubin 3(9.1)111Increase of c -glutamyltransferase 1(3.0)100Increase of triglyceride 5(15.2)041Increase of uric acid 1(3.0)010Dizziness 3(9.1)003Pruritic rash

1(3.0)

1

AEs are summarized by frequencies and percentages

W.Wang et al.

attention to total bilirubin and triglyceride in future clinical trials of sulcardine sulfate.

The pharmacokinetic study using radioisotope was not conducted in human prior to this study due to the condition limits.Therefore,the metabolic pathway of sulcardine sulfate in human has not been?gured out yet,and the exact reason for pharmacokinetic nonlinearity is not certain as well.The pharmacokinetic study using radioisotope could be performed in the future if necessary.

5Conclusions

In this multiple dose study,the pharmacokinetic charac-teristics of sulcardine sulfate were shown to be non-liner, with the modest accumulation upon repeated dosing.Sul-cardine sulfate was generally safe and well tolerated.Acute clinical toxicity at800mg or lower is unlikely. Acknowledgments The authors sincerely thank the healthy volun-teers who participated in the clinical study.

Compliance with Ethical Standards

Funding This work was supported by grants from the Ministry of Science and Technology of China(No.2010ZX09502-003)and the Shanghai Committee of Science and Technology,China(No. 15DZ2291800).

Con?ict of interest None of the authors(Wei Wang,Hong-jie Qian, Liang Xin,Meng-qi Zhang,Dong-ying Lu,Jie-mei Jin,Gang-yi Liu, Jing-ying Jia,Hong-chao Zheng,Chen Yu,Yi-ping Wang,Fu Zhu, and Yun Liu)have any con?icts of interest to report.

Ethical Approval All procedures in this study were in accordance with the1964Helsinki declaration(and its amendments).The study protocol was approved by the Independent Ethics Committee of Shanghai Xuhui Central Hospital,Shanghai,China.

Informed Consent All subjects provided written informed consent prior to start of study-related procedures.References

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Multiple Dose Pharmacokinetics and Safety of Sulcardine Sulfate