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LY01008 had been identified as being highly similar to the bevacizumab reference product in the pharmacy and pharmacology terms. The primary objective of this study was to compare the pharmacokinetic characteristics of the biosimilar candidate LY01008 with that of the bevacizumab (AvastinIn this double-blind, parallel-group, phase I study, 102 male subjects aged 18-45 years were randomized 1:1 to receive a single intravenous infusion of 3 mg/kg LY01008 or bevacizumab. Before the pivotal section, 12 healthy male subjects receiving a single intravenous (IV) infusion of 0.5 mg/kg or 1.5 mg/kg LY01008 were screened to verify the safety and tolerability of LY01008. Primary endpoints included the area under the concentration-time curve (AUC) from time zero to the last quantifiable time point (AUCThe geometric mean ratios (GMRs) (90% confidence intervals, CIs) of AUCLY01008, a recombinant humanized monoclonal antibody (mAb) against vascular endothelial growth factor (VEGF), displayed pharmacokinetic similarity to bevacizumab, and good safety and tolerability profiles. The data from this trial provide fundamental information for further development.Clinical trial registration ID: CTR20170191.

Helicobacter pylori-positive ulcers are treated with a proton pump inhibitor (PPI) + two antibiotics with/without bismuth. The objective of this study was to investigate the pharmacokinetic interaction of the novel PPI anaprazole, amoxicillin and clarithromycin with/without bismuth.This single-centre, randomised, open-label phase 1 pharmacokinetic study included healthy Chinese male participants, comprising two cohorts (cohort 1, 4 × 4 crossover design; cohort 2, 2 × 2 crossover design). In cohort 1, 24 participants received four treatment cycles with a different treatment in each cycle; the washout period between cycles was 9 days. Participants were randomly assigned to one of the following four treatment sequences (1:1:1:1): anaprazole sodium enteric-coated tablet 20 mg monotherapy, amoxicillin 1000 mg monotherapy, clarithromycin 500 mg monotherapy, and a three-drug combination (anaprazole 20 mg, amoxicillin 1000 mg and clarithromycin 500 mg). During each treatment cycle, study drugs were administered twice daily for four consecutive days and once in the morning on the fifth day. Cohort 2 participants were administered a single dose of the three-drug combination and a single dose of a four-drug combination (three-drug combination + bismuth 0.6 g) with a washout period of 11 ± 2 days between treatments. Blood samples were collected for pharmacokinetic analysis.Twenty-nine of 32 enrolled participants (cohort 1, n = 24; cohort 2, n = 8) completed the study. There were no significant differences in exposure or time to reach maximum concentration (TDose adjustments for individual drugs are not necessary with combined dosing of anaprazole, amoxicillin, clarithromycin and bismuth.

SHR0534 is being developed for type-2 diabetes mellitus. Herein the tolerability, safety, pharmacokinetics and pharmacodynamics of SHR0534 in healthy Chinese subjects were assessed in a phase-I, randomized, double-blind, placebo-controlled, single- and multiple-ascending dose study. Forty subjects were randomized 4:1 to receive SHR0534 at the dose of 10, 25, 50 or 100 mg, or placebo, and another eleven subjects were allocated to either the 5 mg group or the placebo group at an 8:3 ratio. All subjects received a single dose on day 1, followed by a 9-day washout and once-daily administrations for 14 consecutive days. Serial samples were collected, and vital signs, electrocardiograms, laboratory tests, urinalysis and adverse events (AEs) were recorded. All doses of SHR0534 were safe and well tolerated with infrequent, generally mild-to-moderate AEs and no serious AEs in the study. SHR0534 was absorbed with a

Ensartinib is a novel, potent and highly selective inhibitor of anaplastic lymphoma kinase (ALK) that has promising clinical activity and low toxicity in patients with ALK-positive non-small cell lung cancer. This study was conducted to investigate the pharmacokinetics, metabolism and excretion of ensartinib following a single 200 mg/100 μCi oral dose of radiolabeled ensartinib to healthy subjects. Six healthy male subjects were enrolled and administrated an oral suspension in a fasted state. Blood, urine and feces were collected. Radioactivity concentrations were measured by liquid scintillation counting and plasma concentrations of ensartinib by liquid chromatography-tandem mass spectrometry. Both techniques were applied for metabolite profiling and characterization. The mean total recovery was 101.21% of the radiolabeled dose with 91.00% and 10.21% excreted in feces and urine, respectively. Unchanged ensartinib was the predominant drug-related component in urine and feces, representing 4.39% and 38.12% of the administered dose, respectively. Unchanged ensartinib and its metabolite M465 were the major circulating components, accounting for the same 27.45% of the plasma total radioactivity (AUC0–24h pool), while other circulating metabolites were minor, accounting for less than 10%. Mean Cmax, AUC0–∞, T1/2 and Tmax values for ensartinib in plasma were 185 ng/mL, 3827 h ng/mL, 18.3 h and 3.25 h, respectively. The total radioactivity in plasma was cleared with terminal half-life of 27.2 h. Treatment with ensartinib was well tolerated, and no serious adverse events were reported. It was well tolerated in the six healthy male subjects following a single oral administration of 200 mg/100 μCi dose of ensartinib. Besides unchanged ensartinib, metabolite of M465 was the predominant circulating drug-related component. The drug was primarily eliminated in feces. ClinicalTrials.gov NCT03804541.

This study aimed to evaluate the bioequivalence (BE) of 2 formulations of the 10-mg rivaroxaban tablet. The study was a randomized, open-label, 4-period, crossover study that included 28 healthy subjects in fasting or fed conditions. The pharmacokinetic parameters were determined based on the concentrations of rivaroxaban using high-performance liquid chromatography with a tandem mass spectrometer detector. In each of the 4 study periods with fasting or fed conditions, a single dose of test or reference product was administered. Rivaroxaban concentrations in plasma were determined using a validated liquid chromatography with a tandem mass spectrometer detector method. The pharmacokinetic parameters assessed were the area under the plasma concentration-time curve (AUC0-t , AUC0-∞ ), the peak plasma concentration of the drug (Cmax ), time to achieve Cmax , elimination half-life, within-subject variability of test drug, and within-subject variability of reference drug. The geometric mean ratio (90%CI) of the test drug/reference drug for rivaroxaban was 90.38% to 103.60% for AUC0-t in fasting conditions and 90.13% to 100.42% in fed conditions. The AUC0-∞ s were 89.94% to 102.50% and 90.14% to 100.45% under fasting and fed conditions, respectively. The Cmax values were 90.58% to 105.01% and 96.36% to 108.07% in these 2 conditions, respectively. All 90%CIs for test drug/reference drug geometric mean ratio were ≤2.5. The 90%CIs for test/reference AUC ratio and Cmax ratio were within the acceptable range for BE. There were no adverse events encountered during this BE study. The study's results indicated that the 2 formulations of the rivaroxaban tablet were bioequivalent.

This study investigated the pharmacokinetics and pharmacodynamics properties, safety and tolerability of cetagliptin.Forty-eight healthy subjects were enrolled in this study. Three cohorts were investigated in sequential order: 50, 100 and 200 mg cetagliptin. Positive control (sitagliptin 100 mg) was designed as open label. Blood samples were collected and analysed for pharmacokinetic and pharmacodynamic properties. Safety and tolerability were assessed throughout the study.Following multiple oral doses, cetagliptin was rapidly absorbed and reached peak plasma concentrations after approximately 1.0-1.5 hours. Plasma cetagliptin concentrations increased at a rate greater than dose. Accumulation of cetagliptin was modest, and steady state was generally achieved at day 5. Doses ≥50 mg of cetagliptin administered once daily will result in sustained dipeptidyl peptidase-4 (DPP-4) inhibition (≥80%). The plasma concentration giving 50% of maximum drug effect of DPP-4 inhibition for cetagliptin (5.29 ng/mL) was lower than that of sitagliptin (7.03 ng/mL). Active glucagon-like-1 peptide (GLP-1) concentrations were significantly increased in the cetagliptin groups by 2.3- to 3.1-fold at day 1 and 3.1- to 3.6-fold at steady state compared with that of placebo, and active GLP-1 concentrations were increased with increasing dose. Compared with sitagliptin, doses ≥100 mg once daily of cetagliptin produced postprandial increases in active GLP-1 level and induced to long-lasting glucose-lowering efficacy. Cetagliptin was well tolerated across all doses studied.Cetagliptin demonstrates the great potential for treatment with type 2 diabetes patients based on the inhibition of DPP-4, the increase in GLP-1 and insulin, the decrease in glucose, and might be more effective in DPP-4 inhibition than sitagliptin.

Background and objectives Cetagliptin is a highly selective dipeptidyl peptidase-4 inhibitor under development to treat type 2 diabetes mellitus. This first-in-human study was conducted to characterise the pharmacokinetics, pharmacodynamics and tolerability of single-ascending oral doses of cetagliptin in healthy subjects. In addition, the effect of food on pharmacokinetics was evaluated. Methods Study 1 enrolled 66 healthy subjects in a double-blind, randomised, placebo-controlled, single-dose escalation study; sitagliptin was employed as a positive open-label control. Forty-four subjects were assigned to seven cohorts (cetagliptin 12.5, 25, 50, 100, 200, 300 or 400 mg); 12 subjects were assigned to the placebo group. The remaining ten subjects received sitagliptin 100 mg as the positive control. Blood, urine and faeces were collected for the pharmacokinetic analysis and determination of plasma dipeptidyl peptidase-4 inhibition, active glucagon-like peptide-1, glucose and insulin levels. In Study 2, 14 healthy subjects were assigned to a randomised, open-label, two-period crossover study, and received a single oral dose of cetagliptin 100 mg in the fasted state or after a high-fat meal, with a 14-day washout period between treatments. Blood samples were collected to evaluate the effects of food on the pharmacokinetics of cetagliptin. Results Following administration of a single oral dose, cetagliptin was rapidly absorbed, presenting a median time to maximum concentration of 1.0-3.25 h. The terminal half-life ranged between 25.8 and 41.3 h, which was considerably longer than that of sitagliptin. The area under the plasma concentration-time curve was approximately dose proportional between 25 mg and 400 mg, and the increase in maximum concentration was greater than dose proportional. The unchanged drug was mainly excreted in the urine (27.2-46.2% of dose) and minimally via the faeces (1.4% of dose). Dipeptidyl peptidase-4 inhibition, an increase in active glucagon-like peptide-1 and a slight decrease in blood glucose were observed, whereas insulin was not significantly altered when compared with placebo. The weighted average dipeptidyl peptidase-4 inhibition by cetagliptin 100 mg was higher than that mediated by sitagliptin 100 mg. Cetagliptin was well tolerated up to a single oral dose of 400 mg. No food effects were noted. Conclusions Cetagliptin inhibited plasma dipeptidyl peptidase-4 activity, increased levels of active glucagon-like peptide-1 and was well tolerated at single doses up to 400 mg, eliciting no dose-limiting toxicity in healthy volunteers. Food did not affect the pharmacokinetics of cetagliptin. Clinical trial registration The studies were registered at http://www.chinadrugtrials.org.cn (Nos. CTR20180167 and CTR20181331).

SY-004, a dual-acting full glucokinase activator, is under development to provide a dose-dependent improvement of glucose control. This study aimed to assess the tolerability, safety, and pharmacokinetic and pharmacodynamic properties of SY-004 in healthy Chinese adults.Two study participants were administered 2 mg of SY-004 in the 2-mg cohort, whereas 6 study participants were randomized with 4 study participants receiving SY-004 and 2 receiving placebo in the 20-mg cohort. In each of other 3 dose cohorts (40, 80, and 120 mg), 12 participants were randomized in a 10:2 ratio to receive single oral SY-004 capsules or placebos. Drug concentrations, glucose and insulin levels, and safety data were assessed and analyzed. Noncompartmental analysis was used to determine SY-004 pharmacokinetic parameters.SY-004 was generally well tolerated. Nine of the 44 study participants reported 17 treatment-related adverse events, and most treatment-related adverse events were mild. SY-004 had approximately dose-proportional increases in systemic exposure. The mean tSY-004, a new potential glucokinase activator, had favorable safety profiles and good PK characteristics. The glucose-lowering effects were slightly dose related. The SY-004 data in healthy Chinese adults supports further development.gov identifier: NCT03171623.

BACKGROUND: Almonertinib Mesilate Tablets (HS-10296, Hansoh Pharma, Shanghai, China) is a novel and selective third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). A phase I study of almonertinib in patients with non-small cell lung cancer (NSCLC) demonstrated a linear metabolic trend, a good tolerability/safety profile, and preliminary antitumor activity. However, the metabolism, excretion, and substance balance of almonertinib has not been clearly determined. Here, we investigated the pharmacokinetic characteristics and safety profile of almonertinib following a single oral dose (110 mg/50 µCi) in healthy Chinese male participants. METHODS: Total radioactivity (TRA) in whole blood, plasma, urine, and feces was measured by utilizing a liquid scintillation counter to obtain almonertinib substance balance data. The pharmacokinetic parameters of [(14)C]almonertinib and the parent drug almonertinib in whole blood and plasma were analyzed with noncompartmental analysis in the WinNonlin software (Pharsight Corp). The major metabolites in plasma, urine, and feces were analyzed by high-performance liquid chromatography (HPLC) coupled with an online or offline isotope detector. The safety of the drug was evaluated after administration. RESULTS: The safety and tolerability of a single oral dose of 110 mg/50 µCi [(14)C] almonertinib suspension were good in healthy Chinese male participants. There was no significant abnormality or special adverse reaction. TRA peaked quickly in plasma, with a T(max) of 4.0 h; however, TRA was cleared slowly in vivo, with a mean terminal elimination phase (half-life, T(1/2)) of up to 863 h. In addition to the parent drug, a total of 26 metabolites in blood, urine, and feces were analyzed. In plasma, parent drug was the major drug-related component, accounting for 69.97% of TRA, and M440 (almonertinib-M2 demethyl product) was the major metabolite, accounting for 5.08% of TRA; in urine, parent drug accounted for 0.48% of the dose administered and HAS-719 was the major metabolite, accounting for 1.20% of the administered dose; in feces, parent drug was about 8.61% of the dose administered and HAS-719 was the major metabolite, accounting for 12.33% of the administered dose, which was followed by M541a/M470a and M617/M575, accounting for 11.8% and 6.76% of the administered dose, respectively. CONCLUSIONS: Almonertinib has a good safety profile, with parent drug as its main circulating component. almonertinib is extensively metabolized in vivo before excretion and is excreted as a parent drug and metabolites mainly via feces. TRIAL REGISTRATION: The trial registration number: CTR20192291.

Globalagliatin, a glucokinase activator, plays a vital role in glucose homeostasis. The aim of this study was to assess the safety, pharmacokinetics, and pharmacodynamics of globalagliatin in Chinese patients with type 2 diabetes. In this dose-titration study, 24 patients were randomized (3:1 ratio) to receive globalagliatin or placebo. The 28-day titration was divided into two stages, each comprising 12 subjects. In stage I (low-dose), globalagliatin or placebo was administered at ascending doses of 20, 40, 80, and 120 mg once daily, increased at weekly intervals. As the treatment was well tolerated, stage II (high-dose) was initiated, with ascending doses of 80, 160, 240, and 320 mg. Safety, pharmacokinetic and pharmacodynamic analysis were conducted. Following once-daily titration with ascending doses of globalagliatin of 20–120 mg (stage I) and 80–320 mg (stage II) for 7 days, globalagliatin caused mildly high incidences of hypoglycemia and hypertriglyceridemia. The mean maximum plasma concentration (Cmax) of globalagliatin increased from 7.76 to 138.13 ng/mL (stage I), and 29.36 to 471.50 ng/mL (stage II), which occurred at 3–5 h post-dose. A steady state was achieved after 7 days of once-daily dosing in stage I and stage II, respectively. Mean area under the plasma-concentration curve for steady-state 24-h interval (AUC0-24) increased from 106.13 to 2461.95 ng·h/mL (stage I) and 369.71 to 9218.38 ng·h/mL (stage II). Fasting plasma glucose (FPG) decreased continuously during the titration period. Compared with the placebo, high-dose globalagliatin significantly increased the reductions in FPG, the area under the curve of 24-h glucose levels, and glycated albumin, with least-squares mean changes (relative to baseline) of − 4.08 mmol/L (95% CI − 5.05 to − 3.12) (P

Ensartinib is a novel, potent and highly selective inhibitor of anaplastic lymphoma kinase (ALK) that has promising clinical activity and low toxicity in patients with ALK-positive non-small cell lung cancer. This study was conducted to investigate the pharmacokinetics, metabolism and excretion of ensartinib following a single 200 mg/100 μCi oral dose of radiolabeled ensartinib to healthy subjects.Six healthy male subjects were enrolled and administrated an oral suspension in a fasted state. Blood, urine and feces were collected. Radioactivity concentrations were measured by liquid scintillation counting and plasma concentrations of ensartinib by liquid chromatography-tandem mass spectrometry. Both techniques were applied for metabolite profiling and characterization.The mean total recovery was 101.21% of the radiolabeled dose with 91.00% and 10.21% excreted in feces and urine, respectively. Unchanged ensartinib was the predominant drug-related component in urine and feces, representing 4.39% and 38.12% of the administered dose, respectively. Unchanged ensartinib and its metabolite M465 were the major circulating components, accounting for the same 27.45% of the plasma total radioactivity (AUCIt was well tolerated in the six healthy male subjects following a single oral administration of 200 mg/100 μCi dose of ensartinib. Besides unchanged ensartinib, metabolite of M465 was the predominant circulating drug-related component. The drug was primarily eliminated in feces.ClinicalTrials.gov NCT03804541.

Tylerdipine hydrochloride (KBP-5660) is a novel L/T-type dual calcium channel blocker developed for the treatment of hypertension. We aimed to study the pharmacokinetics, safety and tolerability of tylerdipine in healthy Chinese subjects. Two double-blind, randomized, dose-escalation studies were conducted that included a total of 88 healthy subjects: (1) a single-ascending dose (SAD) study; and (2) a multiple-ascending dose (MAD) study. In the SAD study, 64 subjects were randomly assigned to receive a single dose of 0.5, 2.5, 5, 10, 15, 20, 25, or 30 mg of tylerdipine or placebo. In the MAD study, 24 subjects were randomly assigned to receive 10 or 20 mg of tylerdipine or placebo once daily for 9 days. Blood samples were collected at the designated time points for pharmacokinetic analyses. Safety assessments were conducted throughout the study. Following a single oral dose of tylerdipine of 5–30 mg, the mean maximum plasma concentration (Cmax) increased from 0.9993 to 10.11 ng/ml; mean area under the plasma-concentration curve (AUC) from time zero to 72 h increased from 4.332 to 73.95 h·ng/ml. AUC increased in a greater than dose-proportional manner, whereas Cmax exhibited a rough but non-typical dose-proportionality increase. In the MAD study, steady-state conditions were achieved after 1 week of daily dosing in both dose groups. Accumulation of tylerdipine was low, with accumulation ratios (RAUC) of less than 1.65. All adverse events were assessed as mild or moderate. Tylerdipine hydrochloride was safe and well tolerated. The exposure (AUC) of tylerdipine over the dose range of 5–30 mg increased in a greater than dose-proportional manner, while Cmax exhibited a rough but non-typical dose proportionality increase. A slight accumulation of tylerdipine was observed following multiple dosing. CTR20140862 and CTR20150660.

For quantitative assaying tylerdipine hydrochloride, and its two primary metabolites (M2 and M4) in human urine, two sensitive and accurate LC-MS/MS methods were firstly developed and validated, where multiple reaction monitoring (MRM) was applied under positive electrospray ionization mode for tylerdipine and negative electrospray ionization mode for M2/M4, respectively. Urinary proteins were precipitated using acetonitrile, and deuterated isotopes of tylerdipine and M4 ([D5]‑tylerdipine and [D6]-M4) were used as internal standards. Triton X-100, a good surfactant, was used to prevent the adsorption. An Agilent Poroshell 120 column was employed for chromatographic separation of the analytes with the mobile phases of 2 mM ammonium formate solution (containing 0.1% formic acid) and acetonitrile (45:55 for tylerdipine and 75:25 for the M2/M4, v/v). Flow rate was 0.3 mL/min. Calibration curves for tylerdipine, M2 and M4 in urine were linear over the ranges of 0.02–10 ng/mL, 2–1500 ng/mL and 0.5–200 ng/mL, respectively. The precision, accuracy, specificity and stability of two methods all evaluated and achieved the acceptable criteria. The LC-MS/MS methods were successfully applied to assay urinary excretion of tylerdipine and the metabolites in healthy Chinese subjects who orally received a single dose of 20 mg tylerdipine tablet. Generally, the urinary excretion of the two primary metabolites accounted for 11.7% of the total dose of tylerdipine in healthy Chinese subjects, while little tylerdipine was recovered in urine.

Objective We aimed to 1) develop physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models of a novel midazolam rectal gel in healthy adults, 2) assess the contribution of different physiologically relevant factors in rectal absorption, and 3) to provide supports for future clinical studies of midazolam rectal gel. Methods We developed the rectal PBPK model after built the intravenous and the oral PBPK model. Then, the physiological progress of rectal route was described in terms of the drug release, the rectal absorption and the particle first-pass elimination. Next, the validated PBPK model was combined with the sigmoid Emax PD model. This PBPK/PD model was used to identify the dose range and the critical parameters to ensure safety sedation. Results Based on the simulations, the recommended maximum dose for adults’ sedation was 15 mg. And the retention time of midazolam rectal gel should be longer than 3 h to reach over 80% pharmacokinetics and pharmacodynamics effects. Conclusion We successfully developed a PBPK/PD model for the midazolam rectal gel, which accurately described the PK/PD behavior in healthy adults and indicated the transit time of rectum was the most sensitive parameter for absorption. This PBPK/PD model would be expected to support the future clinical studies and pediatric application.

Fruquintinib (HMPL-013) is a novel, potent, and highly selective tyrosine kinase inhibitor targeting the vascular endothelial growth factor receptors (1, 2 and 3). This study was conducted to investigate the metabolism, excretion, and pharmacokinetics of HMPL-013 after a single oral dose to healthy Chinese men. Six subjects were administrated an oral suspension containing 5 mg of 14C-labeled HMPL-013 (100 μCi) in a fasted state. Blood and excreta samples were collected at the designated time points or intervals for pharmacokinetics and radiometric analyses. Safety assessments were conducted throughout the study. Over a 336-h post-dose collection period, mean recovery was 90.11% of the radiolabeled dose, with 60.31% in urine and 29.80% in feces. Mean C max, AUC0−∞, and T max for HMPL-013 in plasma were 113 ng/mL, 4797 h ng/mL, and 2 h, respectively. Radioactivity and HMPL-013 were cleared from circulation with terminal half-lives of 41.1 and 33.4 h. HMPL-013 was the predominant circulating radioactive component, representing 72.48% of the total radioactivity. M11 was the major circulating metabolite, accounting for 17.31% of the total radioactivity. An additional seven circulating metabolites were identified, each accounting for less than 5% of the total radioactivity. In urine, HMPL-013 accounted for only 0.50% of the administered dose. Three major metabolites M285, M381, and M409-4 were identified in urine accounting for 10.48, 21.16, and 8.92% of the dose, respectively. In feces, HMPL-013 accounted for 5.34% of the dose. M205, M365-2, and M380 were the major metabolites, accounting for 2.29, 3.30, and 2.59% of the dose, respectively. HMPL-013 was well tolerated and absorbed rapidly, with parent compound being the predominant circulating component. HMPL-013 was extensively metabolized prior to excretion, and urine was the major route of excretion.

Thiosemicarbazones display significant antitumor activity and their copper complexes also exhibit enhanced biological activities in most situations, but the underlying mechanism is poorly understood. Therefore, investigation of the mechanism involved in the change upon chelation is required to extend our understanding of the effects of thiosemicarbazones. In the present study, the inhibitory effect of 2-pyridinecarboxaldehyde thiosemicarbazone (PCT) and its copper complex (PCT-Cu) on cell proliferation was investigated. The copper chelate exhibited a 3- to 10-fold increase in antitumor activity (with an IC50

Background Almonertinib Mesilate Tablets (HS-10296, Hansoh Pharma, Shanghai, China) is a novel and selective third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). A phase I study of almonertinib in patients with non-small cell lung cancer (NSCLC) demonstrated a linear metabolic trend, a good tolerability/safety profile, and preliminary antitumor activity. However, the metabolism, excretion, and substance balance of almonertinib has not been clearly determined. Here, we investigated the pharmacokinetic characteristics and safety profile of almonertinib following a single oral dose (110 mg/50 µCi) in healthy Chinese male participants. Methods Total radioactivity (TRA) in whole blood, plasma, urine, and feces was measured by utilizing a liquid scintillation counter to obtain almonertinib substance balance data. The pharmacokinetic parameters of [14C]almonertinib and the parent drug almonertinib in whole blood and plasma were analyzed with noncompartmental analysis in the WinNonlin software (Pharsight Corp). The major metabolites in plasma, urine, and feces were analyzed by high-performance liquid chromatography (HPLC) coupled with an online or offline isotope detector. The safety of the drug was evaluated after administration. Results The safety and tolerability of a single oral dose of 110 mg/50 µCi [14C] almonertinib suspension were good in healthy Chinese male participants. There was no significant abnormality or special adverse reaction. TRA peaked quickly in plasma, with a Tmax of 4.0 h; however, TRA was cleared slowly in vivo, with a mean terminal elimination phase (half-life, T1/2) of up to 863 h. In addition to the parent drug, a total of 26 metabolites in blood, urine, and feces were analyzed. In plasma, parent drug was the major drug-related component, accounting for 69.97% of TRA, and M440 (almonertinib-M2 demethyl product) was the major metabolite, accounting for 5.08% of TRA; in urine, parent drug accounted for 0.48% of the dose administered and HAS-719 was the major metabolite, accounting for 1.20% of the administered dose; in feces, parent drug was about 8.61% of the dose administered and HAS-719 was the major metabolite, accounting for 12.33% of the administered dose, which was followed by M541a/M470a and M617/M575, accounting for 11.8% and 6.76% of the administered dose, respectively. Conclusions Almonertinib has a good safety profile, with parent drug as its main circulating component. almonertinib is extensively metabolized in vivo before excretion and is excreted as a parent drug and metabolites mainly via feces. Trial registration The trial registration number: CTR20192291.

In situ gelling thermosensitive hydrogel formulation has been reported to effectively sustain the release of macromolecules for a long time. However, the low-molecular-weight hydrophilic drugs, such as doxorubicin (DOX), are not suitable for intratumoral injection because the release will complete within one day. In this study, liposomal doxorubicin (LipDOX) was added into the hydrogel to form a novel thermosensitive formulation which prolonged the sustained release of DOX. DOX+C/GP (doxorubicin in chitosan/β-glycerophosphate) was prepared to compare with LipDOX+C/GP (liposomal doxorubicin in chitosan/β-glycerophosphate hydrogel). The particle size of DOX-loaded liposome was 94.2nm and the encapsulation efficiency of DOX was near 98%. In vitro release experiments, the release of DOX in both DOX+C/GP group and LipDOX+C/GP group increased along with the increasing pH of buffers. However, the LipDOX+C/GP group with lower initial burst release had a much longer releasing duration than DOX+C/GP group (21days vs. 24h). In vitro and in vivo antitumor experiments demonstrated that LipDOX+C/GP group had better antineoplastic effect and less toxicity than DOX+C/GP group. Pharmacokinetics study showed LipDOX+C/GP exhibited a higher AUC0-t and longer MRT than DOX+C/GP in blood and tumor, which indicated that LipDOX+C/GP obtained an enhanced antitumor activity compared with DOX+C/GP. In addition, the lower distribution index (the ratio of AUC of normal tissue/AUC of tumor tissue) of the LipDOX+C/GP implied it had lower toxicity to normal tissues than DOX+C/GP. Therefore, the novel thermosensitive hydrogel formulation was potential for clinical application in cancer treatment.

The aim of this analysis was to explore the influence of CYP3A4*1G and CYP3A5*3 polymorphisms on the pharmacokinetics of tylerdipine in healthy Chinese subjects.A total of 64 and 63 healthy Chinese subjects were included and identified as the genotypes of CYP3A4*1G and CYP3A5*3, respectively. Plasma samples were collected for up to 120 h post-dose to characterize the pharmacokinetic profile following single oral dose of the drug (5, 15, 20, 25 and 30 mg). Plasma levels were measured by a high-performance liquid chromatography-mass spectrometry (LC-MS/MS). The pharmacokinetic parameters were calculated using non-compartmental method. The maximum concentration (Cmax) and the area under the curve (AUC0–24 h) were all corrected by the dose given.In the wild-type group, the mean dose-corrected AUC0–24 h was 1.35-fold larger than in CYP3A4*1G carriers (p = .018). Among the three CYP3A5 genotypes, there showed significantly difference (p = .008) in the t1/2, but no significant difference was observed for the AUC0–24 h and Cmax. In subjects with the CYP3A5*3/*3 genotype, the mean t1/2 was 1.35-fold higher than in CYP3A5*1/*1 group (p = .007). And the t1/2 in CYP3A5*3 carriers also was 1.32-fold higher than in the wild-type group (p = .004).CYP3A4*1G and CYP3A5*3 polymorphisms may influence tylerdipine pharmacokinetic in healthy Chinese subjects. The aim of this analysis was to explore the influence of CYP3A4*1G and CYP3A5*3 polymorphisms on the pharmacokinetics of tylerdipine in healthy Chinese subjects. A total of 64 and 63 healthy Chinese subjects were included and identified as the genotypes of CYP3A4*1G and CYP3A5*3, respectively. Plasma samples were collected for up to 120 h post-dose to characterize the pharmacokinetic profile following single oral dose of the drug (5, 15, 20, 25 and 30 mg). Plasma levels were measured by a high-performance liquid chromatography-mass spectrometry (LC-MS/MS). The pharmacokinetic parameters were calculated using non-compartmental method. The maximum concentration (Cmax) and the area under the curve (AUC0–24 h) were all corrected by the dose given. In the wild-type group, the mean dose-corrected AUC0–24 h was 1.35-fold larger than in CYP3A4*1G carriers (p = .018). Among the three CYP3A5 genotypes, there showed significantly difference (p = .008) in the t1/2, but no significant difference was observed for the AUC0–24 h and Cmax. In subjects with the CYP3A5*3/*3 genotype, the mean t1/2 was 1.35-fold higher than in CYP3A5*1/*1 group (p = .007). And the t1/2 in CYP3A5*3 carriers also was 1.32-fold higher than in the wild-type group (p = .004). CYP3A4*1G and CYP3A5*3 polymorphisms may influence tylerdipine pharmacokinetic in healthy Chinese subjects.

Tylerdipine hydrochloride is a novel L-type and T-type dual calcium channel antagonist that has the potential effects of expanding blood vessels and lowering blood pressure. It is expected to reduce the side effect of ankle edema observed with other drugs in the same class. A randomized, open-label, crossover phase 1 study was performed to evaluate the effect of food on the bioavailability of tylerdipine. Fourteen healthy male volunteers were enrolled. The administration of tylerdipine after a high-fat meal increased the bioavailability of tylerdipine. In the fed state there was a 130% increase in the mean total systemic exposure (AUCinf ) and a 73% increase in the mean peak plasma concentration (Cmax ) compared with that in the fasting state. The geometric mean ratios (90% confidence interval) of Cmax and AUCinf were 2.54 (1.94, 3.33) and 1.75 (1.50, 2.04) for tylerdipine. The exposures of the 2 main metabolites M2 and M4 were increased by approximately 10% after a high-fat meal. The median time to peak plasma concentration of tylerdipine showed no difference between fasting and fed states.

1. β-caryophyllene alcohol (BCPA) has shown therapeutic promise in the treatment of asthma and inflammation with low toxicity. The aim of the current study was to report the pharmacokinetic profiles of BCPA in rats and dogs. 2. Following intravenous administration, BCPA exhibited moderate volumes of distribution (Vz) ranging from 5.63 to 8.97 L/kg in rats and low Vz (2.89 ± 1.12 L/kg) in dogs. Systemic plasma clearance was high in both species, resulting in a short elimination half-life ranging from 29.6 to 48.3 min. In rats, the intravenous pharmacokinetics was dose dependent. The measured oral bioavailability was low in rats for BCPA solution (1.17 ± 0.78%), suspension (1.21 ± 0.33%) and PEG formulation (6.22 ± 2.63%). The bioavailability was lower in dogs for BCPA solution (0.12 ± 0.05%) and PEG formulation (0.25 ± 0.07%), indicating significant species difference. However, treatment of plasma samples with β-glucuronidase increased the systematic exposure of BCPA as assessed from AUC (0-∞) by 24.7- or 2.62-fold in rats and dogs, respectively, which suggested glucuronidation was a significant metabolic pathway for BCPA possibly due to first-pass metabolism. 3. In summary, this was the first preclinical pharmacokinetic investigation of BCPA in animals, providing vital knowledge for further preclinical research and subsequent clinical trials.

Fruquintinib (HMPL-013) is a novel, potent, and highly selective tyrosine kinase inhibitor targeting the vascular endothelial growth factor receptors (1, 2 and 3). This study was conducted to investigate the metabolism, excretion, and pharmacokinetics of HMPL-013 after a single oral dose to healthy Chinese men.Six subjects were administrated an oral suspension containing 5 mg ofOver a 336-h post-dose collection period, mean recovery was 90.11% of the radiolabeled dose, with 60.31% in urine and 29.80% in feces. Mean CHMPL-013 was well tolerated and absorbed rapidly, with parent compound being the predominant circulating component. HMPL-013 was extensively metabolized prior to excretion, and urine was the major route of excretion.

The compound series of traditional anticholinergics [atropine (Atr), anisodamine (Ani), anisodine (AT3), and scopolamine (Sco)], naturally occurring belladonna alkaloid, have been approved for numerous therapeutic uses since 1970s. Tiotropium, a novel M receptor antagonist for the treatment of chronic obstructive pulmonary disease, was structurally modified based on atropine-like drugs. Clinical phenomena suggested that the changes of substituent group were related to the pharmacokinetic and pharmacodynamic characteristics of the agents. In an attempt to compare the pharmacokinetics of the series of anticholinergics and investigate the subsets motivating selective anticholinergic potencies, a sensitive LC–MS/MS method was established to analyze the differences of pharmacokinetic parameters. In this paper, we determined the pharmacokinetics of atropine, anisodamine, anisodine, scopolamine, and tiotropium after i.v. and i.g. single dose administration. After i.v. administration, the maximum drug plasma concentrations (C max) of Atr, Ani, AT3, and Sco were 274.25 ± 53.66, 267.50 ± 33.16, 340.50 ± 44.52, and 483.75 ± 78.13 ng/mL. Tiotropium had a slightly higher area under the curve with a significant increase of C max value. Because of their partial solubility, Atr, Ani, AT3, and Sco had different bioavailability in rats of 21.62, 10.78, 80.45 and 2.52 %, respectively. Following i.g. administration of tiotropium, the C max value below 20 ng/mL revealed the very low oral absorption. The urinary excretion rates of Atr, Ani, AT3, Sco and tiotropium were 11.33, 54.86, 32.67, 8.69 and 73.91 %. This work provided relatively comprehensive preclinical data on the series of anticholinergics, which may be used to explain the clinical adverse effects and applications.

An X-ray crystallographic structure is described for unliganded Vaccinia virus poly(A) polymerase monomer (VP55), showing the first domain-level structural isoforms among either VP55, it’s processivity factor VP39, or the VP55-VP39 heterodimer. The occurrence of domain-level motion specifically in monomeric VP55 is consistent with the finding that the monomeric protein undergoes saltatory translocation whereas the heterodimer does not. Vaccinia virus poly(A) polymerase (VP55) is the only known polymerase that can translocate independently with respect to single-stranded nucleic acid (ssNA). Previously, its structure has only been solved in the context of the VP39 processivity factor. Here, a crystal structure of unliganded monomeric VP55 has been solved to 2.86 A resolution, showing the first backbone structural isoforms among either VP55 or its processivity factor (VP39). Backbone differences between the two molecules of VP55 in the asymmetric unit indicated that unliganded monomeric VP55 can undergo a ‘rocking’ motion of the N-terminal domain with respect to the other two domains, which may be ‘rigidified’ upon VP39 docking. This observation is consistent with previously demonstrated experimental molecular dynamics of the monomer during translocation with respect to nucleic acid and with different mechanisms of translocation in the presence and absence of processivity factor VP39. Side-chain conformational changesmore » in the absence of ligand were observed at a key primer contact site and at the catalytic center of VP55. The current structure completes the trio of possible structural forms for VP55 and VP39, namely the VP39 monomer, the VP39–VP55 heterodimer and the VP55 monomer.« less

As a result of a recent letter to the editor [1], we would like to make several corrections to ourmanuscript [2].We would like to correct the sentence on page 1: “no studies have examined the effects ofthe interaction between Dp44mT and biological molecules, such as proteins and nucleic acids”.This sentence should read: “information related to the effects of the interaction between Dp44mTand biological molecules such as human serum albumin (HSA) or DNA has not yet been fully andsystematically studied”.Furthermore, we provide information on the correctness and purity of the synthesized Dp44mT.

Ginkgo terpene lactones meglumine injection (GMI) is a novel preparation of traditional Chinese medicine that contains ginkgolides A, B and K (GA, GB, GK, respectively) as its primary components. In this study we evaluated the safety, tolerability and pharmacokinetics of these three ginkgolides after single and multiple intravenous infusions of GMI. We also investigated the effect of GMI on cytochrome P450 3A4 (CYP3A4) in healthy Chinese volunteers. In this open-label, placebo-controlled study 15 subjects were randomly assigned to receive GMI or matched placebo (4:1 ratio). All subjects first received midazolam (MDZ) on day 1, followed by a 6-day washout. On Day 8, the subjects were started on once-daily dosing of either GMI or placebo for 14 days. Lastly, on Day 22 the subjects were given second dose of MDZ + GMI or MDZ + placebo. Plasma concentrations of ginkgolides, MDZ and its metabolite 1-hydroxy midazolam were quantified. The steady-state conditions of GA, GB and GK were achieved after 6 days of daily dosing. Following a single dose of GMI (Day 8) the area under the concentration–timecurve from zero to 24 h after administration (AUC0-24h) of GA, GB and GK (arithmetic ± standard deviation) was 4.10 ± 1.06, 4.61 ± 1.31 and 0.127 ± 0.102 h μg/mL, respectively; the corresponding values following multiple doses of GMI (Day 19) were 3.94 ± 1.16, 5.00 ± 1.55 and 0.118 ± 0.096 h μg/mL, respectively. The mean accumulation ratios were 0.95, 1.08 and 0.89 for GA, GB and GK, respectively. Additionally, the geometric mean [peak concentration (Cmax) and AUC0-24h] ratios of MDZ and 1-hydroxy midazolam were all within the specified acceptance ranges in the MDZ + placebo treatment and MDZ + GMI treatment. Our results show that GMI was well tolerated during the entire study. There was no systemic accumulation and no significant effects on the pharmacokinetics of MDZ in healthy Chinese male subjects after repeated dosing of GMI.

Di-2-pyridylketone-4,4,-dimethyl-3-thiosemicarbazone (Dp44mT) exhibits significant antitumor activity. However, the mechanism of its pharmacological interaction with human serum albumin (HSA) and DNA remains poorly understood. Here, we aimed to elucidate the interactions of Dp44mT with HSA and DNA using MTT assays, spectroscopic methods, and molecular docking analysis. Our results indicated that addition of HSA at a ratio of 1:1 did not alter the cytotoxicity of Dp44mT, but did affect the cytotoxicity of the Dp44mT-Cu complex. Data from fluorescence quenching and UV-VIS absorbance measurements demonstrated that Dp44mT could bind to HSA with a moderate affinity (Ka = approximately 10⁴ M(-1)). CD spectra revealed that Dp44mT could slightly disrupt the secondary structure of HSA. Dp44mT could also interact with Ct-DNA, but had a moderate binding constant (KEB = approximately 10⁴ M(-1)). Docking studies indicated that the IB site of HSA, but not the IIA and IIIA sites, could be favorable for Dp44mT and that binding of Dp44mT to HSA involved hydrogen bonds and hydrophobic force, consistent with thermodynamic results from spectral investigations. Thus, the moderate binding affinity of Dp44mT with HSA and DNA partially contributed to its antitumor activity and may be preferable in drug design approaches.

The drug, di-2-pyridylketone-2-pyridine carboxylic acid hydrazone (DPPCAH) and its copper complex (DPPCAH-Cu) exhibit significant antitumor activity. However, the mechanism of their pharmacological interaction with the biological molecule bovine serum albumin (BSA) remains poorly understood. The present study elucidates the interactions between the drug and BSA through MTT assays, spectroscopic methods and molecular docking analysis. Our results indicate that BSA could attenuate effect on the cytotoxicity of DPPCAH, but not DPPCAH-Cu. Data from fluorescence quenching measurements demonstrated that both DPPCAH and DPPCAH-Cu could bind to BSA, with a reversed effect on the environment of tryptophan residues in polarity. CD spectra revealed that the DPPCAH-Cu exerted a slightly stronger effect on the secondary structure of BSA than DPPCAH. The association constant of DPPCAH with BSA was greater than that of DPPCAH-Cu. Docking studies indicated that the binding of DPPCAH to BSA involved a greater number of hydrogen bonds compared to DPPCAH-Cu. The calculated distances between bound ligands and tryptophans in BSA were in agreement with fluorescence resonance energy transfer results. Thus, the binding affinity of the drug (DPPCAH or DPPCAH-Cu) with BSA partially contributes to its antitumor activity; the greater the drug affinity is to BSA, the less is its antitumor activity.

Benzoic acid nitrogen mustard and its rare earth metal complexes were synthesized and characterized by elemental analyses, IR, electronic spectrum, and EPR. The interaction of synthesized complexes with Ct-DNA was investigated and reviewed as a mixed manner of both intercalation and alkylation via fluorescence titration. Their biological activities were also evaluated in K562 and Vero cell lines, indicating that complexes had a significant inhibitory effect; however, there was no synergistic effect instead of antagonistic effect compared to benzoic acid nitrogen mustard. The possible mechanism through cellular apoptosis was also explored by comet assay.

Many anticancer drugs used in the clinical have potent metal chelating ability. The formed metal complex(es) may exhibit improved (or antagonistic) antitumor activity. However, the underlying mechanism has received limited attention. Therefore, investigation of the mechanism involved in the change upon chelation is required to extend our understanding of the effects of various drugs. In the present study, the proliferation inhibition effect of benzaldehyde nitrogen mustard-2-pyridine carboxylic acid hydrazone (BNMPH) and its copper complex on tumor cell lines was investigated. The copper chelate exhibited almost a 10-fold increase in antitumor activity (with IC50

In the present study, 2-pyridinecarboxaldehyde 2-pyridinecarboxylic acid hydrazone (PPAH) was prepared and its antitumor activity was evaluated. The inhibition of proliferation of PPAH against the HepG2 and HCT-116 cell lines was less effective, yet in the presence of copper ions, the mixture demonstrated excellent antitumor activity (IC50 at 2.75±0.30 µM for the HepG2 cell line, and 1.90±0.20 µM for the HCT-116 cell line, respectively) and the new active species was confirmed to be a PPAH copper complex with a 1:1 ratio by spectral analysis. The excellent antitumor activity of the copper complex prompted us to investigate the underlying mechanism. RT-PCR was performed to detect the changes in the expression of apoptotic genes induced by PPAH and its copper complex. However, no changes were observed when the cells were treated by the agents for 24 or 48 h, indicating that ROS were unlikely involved. Cell cycle analysis showed that both PPAH and its copper complex led to S phase arrest of the cells. The sDNA relaxation assay revealed that the PPAH-copper complex displayed dual topoisomerase inhibition for type I and II. The data suggest that the inhibition of proliferation exhibited by the PPAH copper complex may stem from its dual topoisomerase inhibition, which is rarely observed for a metal complex.

Currently protease assay kits, requiring substrate that is either radiolabeled or fluorescence labeled and specialized instruments, are all expensive. A simple, reliable assay of protease activity and its inhibitor screening for general laboratory is rare. Here we demonstrated a straightforward ninhydrin-based method for assay of collagenase activity and its inhibitor screening using spectrophotometry. In the method, without multistep sample treatments and substrate labeling, the hydrolytic products were directly traced by ninhydrin. The method is expected to be suitable for not only the assay of collagenase activity but also the others matrix metalloproteinases activities, and can be used for kinetic study.

The Mannich base containing ciprofloxacin and kojic acid structural units was prepared and evaluated in antitumor activity. The enhancement in antitumor activity was observed both from the Mannich base (IC(50): 103.3±5.0 µM for HepG2, 87.9±8.0 µM for HCT-116 cell) and its copper complex (IC(50): 11.5±1.8 µM for HepG2, 44.4±2.5 µM for HCT-116 cell) compared to the ciprofloxacin and kojic acid. The mechanistic studies via RT-PCR, cell cycle analysis, mitochondrial membrane potential measurement, inhibition of topoisomerase and molecular docking indicated that there is a different molecular mechanism between the Mannich base and its copper complex. The cytotoxicity of the Mannich base was involved in apoptosis, cell cycle arrest, depolarization of mitochondrial membrane and weaker topoisomerase II inhibition, but the copper complex exerted its cytotoxicity mainly through dual topoisomerase inhibition, especially stabilizing the intermediate of cleavage DNA-topoisomerase complex.

The antitumor property of iron chelators and aromatic nitrogen mustard derivatives has been well documented. Combination of the two pharmacophores in one molecule in drug designation is worth to be explored. We reported previously the syntheses and preliminary cytotoxicity evaluation of benzaldehyde nitrogen mustard pyridine carboxyl acid hydrazones (BNMPH) as extended study, more tumor cell lines (IC50for HepG2: 26.1 ± 3.5 μM , HCT-116: 57.5 ± 5.3 μM, K562: 48.2 ± 4.0 μM, and PC-12: 19.4 ± 2.2 μM) were used to investigate its cytotoxicity and potential mechanism.In vitroexperimental data showed that the BNMPH chelating Fe2+caused a large number of ROS formations which led to DNA cleavage, and this was further supported by comet assay, implying that ROS might be involved in the cytotoxicity of BNMPH. The ROS induced changes of apoptosis related genes, but the TFR1 and NDRG1 metastatic genes were not obviously regulated, prompting that BNMPH might not be able to deprive Fe2+of ribonucleotide reductase. The BNMPH induced S phase arrest was different from that of iron chelators (G1) and alkylating agents (G2). BNMPH also exhibited its inhibition of human topoisomerase IIα. Those revealed that the cytotoxic mechanism of the BNMPH could stem from both the topoisomerase II inhibition, ROS generation and DNA alkylation.

Objectives The clinical application of doxorubicin (DOX) is limited by severe systemic side effects. The aim of this study was to develop a strategy that combined the liposomal DOX (LipDOX) and intratumoral injection to reduce the toxicity and enhance the antitumor efficiency. Methods The pharmacokinetics, tissue distribution and pharmacodynamics of LipDOX compared with free DOX were investigated by intratumoral injection in murine H22 hepatoma-bearing mice at a dose of 20 mg/kg body weight. A sensitive HPLC-tandem mass spectrometry method was used to determine the DOX levels in plasma and tissues. The tumour volume and body weight of mice were measured every 3 days. Key findings LipDOX administration resulted in 1.3-fold longer mean residence time (MRT) and 2.4-fold higher area under concentration (AUC)-time curve compared with free DOX administration in tumour. Free DOX caused higher peak plasma concentration (Cmax) than LipDOX in plasma and major organs, which may result in significant mortality for acute cardiac toxicity. After successive 21 days treatment, the final volume of tumour treated by normal saline, free DOX and LipDOX was 5.0-, 1.3-fold higher and 1.6-fold lower than the initial tumour volume, respectively. Conclusions Our results indicated that the intratumoral injection of LipDOX is a promising approach with higher therapeutic efficacy and lower systemic toxicity than free DOX.

This response refers to:Xu, Z.; Liu, Y.; Zhou, S.; Fu, Y.; Li, C. Analysis of the Interaction of Dp44mT with Human SerumAlbumin and Calf Thymus DNA Using Molecular Docking and Spectroscopic Techniques. Int. J.Mol. Sci. 2016 , 17, 1042.Merlot, A.M.; Sahni, S.; Lane, D.J.R.; Richardson, V.; Huang, M.L.H.; Kalinowski, D.S.;Richardson, D.R. Letter to the Editor: Analysis of the Interaction of Dp44mT with Human SerumAlbumin and Calf Thymus DNA Using Molecular Docking and Spectroscopic Techniques and. Int. J.Mol. Sci. 2016 , 17, 1916. Keywords: Dp44mT; fluorescence quenching; molecular docking; human serum albumin;cytotoxicity; MTT; spectroscopy; circular dichroism Dear Editors, Thank you for forwarding the concerns (or comments) from Dr. Richardson [1] regarding ourpaper “Analysis of the Interaction of Dp44mT with Human Serum Albumin and Calf Thymus DNAUsing Molecular Docking and Spectroscopic Techniques” [2], which was recently published in theInternational Journal of Molecular Sciences. We are aware of the fact that Dr. Richardson in a leadingresearcher in the field and both respect Dr. Richardson and regularly refer to the many publicationsfrom his group.Nonetheless, we would like to respond to the specific concerns raised by Dr. Richardson.In reading the article by Xu, Z., et al. entitled “Analysis of the Interaction of Dp44mT with Human SerumAlbumin and Calf Thymus DNA Using Molecular Docking and Spectroscopic Techniques” [Int. J. Mol. Sci.2016, 17, 1042], there is evidence that some of the key methods and comparisons utilized in this study arenon-optimal and problematic.We would also like to bring to the attention of readers a number of important flaws and factually incorrectstatements in this article.The paper examines the binding of the anti-cancer agent, di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT), to human serum albumin (HSA) and DNA and states (page 1, Introduction

Vaccinia virus protein VP55 translocates continuously with respect to single-stranded nucleic acid while extending its 3'end. Here, all key sites of polymerase-primer interaction were identified, demonstrating the wrapping or looping of polyadenylation primer around the polymerase during translocation. Side-chain substitutions at one of the sites indicated its requirement for tail extension beyond approximately 12 nucleotides in length, and conformational changes observed upon oligonucleotide binding suggested allosteric connectivity during translocation. Conformational changes in VP39 upon VP55 binding suggested that, within the VP55-VP39 complex, VP39's mRNA 5' cap binding site closes. The crystallographic structure showed a PAPase catalytic center without side-chain substitutions, possessing two metal ions and with all known reactive and catalytic groups represented, fitting a classical two-metal ion mechanism for phosphoryl transfer.

Combination therapy has generated significant interest in the clinical setting since it increases the therapeutic potential of anticancer drugs. The potential therapeutic benefits in combination of cisplatin and ciprofloxacin have not been fully explored in hepatocellular carcinoma cancer therapy. In the results to be presented here, cellular viability of Hep G2 and Bel-7402 was determined by the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) (MTT) assay and the assessment of synergism, additivity or antagonism was carried out by the median effect analysis. Mechanism of cytotoxicity of the drugs was probed by reverse transcriptase-polymerase chain reaction (RT-PCR). Cellular DNA breaks were evaluated by comet assay. In addition, the effect of the drugs on topoisomerases was also investigated. The results show that ciprofloxacin could affect viability of Hep G2 and Bel-7402 lines, its combination with cisplatin resulted in mixed interactions; synergistic and additive effect. Further investigation indicated that the synergistic effect or additive was correlated to Fas involved apoptotic path, but the effects in combination on topoisomerases were not evident. The results obtained in this study suggest that the therapeutic benefit of cisplatin anti-hepatocellular carcinoma (HCC) may be influenced by ciprofloxacin. Key words: ciprofloxacin, cisplatin, combination, synergistic effect, hepatocellular carcinoma cell line, apoptosis.