scholarly journals Pharmacokinetics of the disialoganglioside, GD2, a circulating tumor biomarker for neuroblastoma, in nonhuman primates

2021 ◽  
Vol 10 ◽  
pp. 26-29
Author(s):  
Frank M. Balis ◽  
Cynthia Lester McCully ◽  
Christine M. Busch ◽  
Elizabeth Fox ◽  
Katherine E. Warren

Background: The ganglioside GD2 is a potential circulating tumor biomarker for the childhood cancer, neuroblastoma. Interpreting the levels of a circulating tumor biomarker depends in part on a knowledge of the biomarker’s clinical pharmacology. Background: The ganglioside GD2 is a potential circulating tumor biomarker for the childhood cancer neuroblastoma. Interpreting the levels of a circulating tumor biomarker depends in part on a knowledge of the biomarker’s clinical pharmacology. Methods: We studied the plasma and cerebrospinal fluid (CSF) pharmacokinetics of the C18 lipoform of GD2 in two nonhuman primates with indwelling subcutaneous CSF lateral ventricular reservoir systems. GD2 was quantified with a validated high-performance liquid chromatography (HPLC)/tandem mass spectrometry assay. GD2 was administered as a short intravenous infusion and frequent plasma and CSF samples were drawn over 72 hours. Results: GD2 plasma concentration declined monoexponentially with a half-life of 16 hours. Clearance was 0.0136 and 0.0131 L/h and volume of distribution (Vd) was 0.035 and 0.038 L/kg in the two animals. Vd was equivalent to plasma volume. Greater than 98% of GD2 in plasma is in a bound form consistent with its known association with lipoproteins and accounting for its limited volume of distribution. GD2 did not cross over from plasma into the CSF. Conclusions: The pharmacokinetic profile of GD2 is favorable for a circulating tumor biomarker. This study demonstrates the value of characterizing the clinical pharmacology of circulating biomarkers to better understand their clinical behavior.

2004 ◽  
Vol 56 (6) ◽  
pp. 695-700
Author(s):  
E.J. Picco ◽  
D.C. Diaz David ◽  
T. Encinas ◽  
M.R. Rubio ◽  
J.C. Boggio

The pharmacokinetic profile of sodium meclofenamate, a non-steroidal antiinflammatory drug, was determined in six pre-ruminant calves after intravenous and intramuscular administration at a dose of 2.2mg/kg of body weight. Meclofenamate concentrations were measured using a high performance liquid chromatography assay. The pharmacokinetics of sodium meclofenamate after intravenous and intramuscular administration to calves were characterised by a rapid distribution phase (t½alpha ), 15.45± 4.85min and 23.14± 7.24min for the intravenous and intramuscular administration, respectively, followed by a longer elimination phase (t½beta ) after intramuscular treatment (17.55± 6.52h.). The apparent volume of distribution (Vd) of the drug after intravenous administration was moderate (0.72± 0.12l/kg), and high (3.51± 1.05l/kg) after intramuscular administration. This can be explained by the flip-flop effect or by enterohepatic shunting. The bioavailability achieved after intramuscular administration was 61%.


Author(s):  
Ajay K. Ola ◽  
Harpal S. Sandhu ◽  
Vinod K. Dumka ◽  
Bibhuti Ranjan

Pharmacokinetics and urinary excretion of an intravenous dose of 5 mg.kg–1 ofloxacin were investigated in water buffalo calves. Plasma concentrations of ofloxacin were determined by high-performance liquid chromatography. Ofloxacin was rapidly distributed from the central to the peripheral compartment as evidenced by a short distribution half-life (0.09 h ± 0.003 h) and high K12 (4.7 h–1 ± 0.1 h–1), and was detected in plasma for 8 h. The large volume of distribution (2.48 L.kg–1 ± 0.18 L.kg–1) obtained in this study indicated high distribution of ofloxacin in water buffalo calves. The elimination half-life, the area under the plasma drug concentration–time curve and total body clearance were 2.11 h ± 0.13 h, 6.20 µg.mL—1 ± 0.23 µg.mL—1.h and 0.81 mL.kg–1.h–1 ± 0.03 mL.kg–1.h–1, respectively. About 18.7% of administered drug was bound to plasma proteins and approximately 32.5% of the administered dose was recovered in urine within 48 h. The results of the study indicated a favourable pharmacokinetic profile of ofloxacin in water buffalo calves, which suggests that ofloxacin may be effective against urinary pathogens in this species.


2006 ◽  
Vol 104 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Wang Ning ShangGuan ◽  
QingQuan Lian ◽  
Leon Aarons ◽  
Ivan Matthews ◽  
ZengShou Wang ◽  
...  

Background There is no information about the pharmacokinetic profile of propofol in Chinese children younger than 3 yr. This study was designed to determine a complete pharmacokinetic profile of a single dose of propofol in Chinese children of different ages. Methods Arterial blood samples were obtained from 35 children with an American Society of Anesthesiologist physical status of I or II at 2, 4, 6, 8, 10, 20, 30, 45, 60, 90, 120, and 180 min after a single bolus intravenous injection of propofol (3 mg/kg). The plasma concentrations of propofol were measured using high-performance liquid chromatography with an ultraviolet detector. A population model was used to estimate the pharmacokinetics of propofol. Results A three-compartment pharmacokinetic model best described the pharmacokinetics of propofol. Clearance was 0.185 l/min, the volume of distribution of the central compartment was 7.41 l, the peripheral volumes of distribution were 54.6 and 7.2 l, and the intercompartmental clearances were 0.614 and 0.692 l/min for a child of the average weight of 13.7 kg. The half-lives were 2.67, 14.89, and 310.60 min. Covariate models were applied, and weight was found to be significant covariate for the clearance and volume of distribution parameters. No significant age effect could be demonstrated on clearance or volume of distribution parameters after weight was taken into account. Conclusions This study supports the case that the pharmacokinetic properties of propofol do not differ substantially across Chinese children of different ages after weight has been accounted for.


Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 437
Author(s):  
Marta Tikhomirov ◽  
Błażej Poźniak ◽  
Tomasz Śniegocki

The precise and reliable determination of buprenorphine concentration is fundamental in certain medical or research applications, particularly in pharmacokinetic studies of this opioid. The main challenge is, however, the development of an analytical method that is sensitive enough, as the detected in vivo concentrations often fall in very low ranges. Thus, in this study we aimed at developing a sensitive, repeatable, cost-efficient, and easy HPLC analytical protocol for buprenorphine in rabbit plasma. In order to obtain this, the HPLC-MS2 system was used to elaborate and validate the method for samples purified with liquid-liquid extraction. Fragment ions 468.6→396.2 and 468.6→414.2 were monitored, and the method resulted in a high repeatability and reproducibility and a limit of quantification of 0.25 µg/L with a recovery of 98.7–109.0%. The method was linear in a range of 0.25–2000 µg/L. The suitability of the analytical procedure was tested in rabbits in a pilot pharmacokinetic study, and it was revealed that the method was suitable for comprehensively describing the pharmacokinetic profile after buprenorphine intravenous administration at a dose of 300 µg/kg. Thus, the method suitability for pharmacokinetic application was confirmed by both the good validation results of the method and successful in vivo tests in rabbits.


2011 ◽  
Vol 55 (6) ◽  
pp. 2927-2936 ◽  
Author(s):  
J. B. Bulitta ◽  
M. Kinzig ◽  
C. B. Landersdorfer ◽  
U. Holzgrabe ◽  
U. Stephan ◽  
...  

ABSTRACTCystic fibrosis (CF) patients are often reported to have higher clearances and larger volumes of distribution per kilogram of total body weight (WT) for beta-lactams than healthy volunteers. As pharmacokinetic (PK) data on cefpirome from studies of CF patients are lacking, we systematically compared its population PK and pharmacodynamic breakpoints for CF patients and healthy volunteers of similar body size. Twelve adult CF patients (median lean body mass [LBM] = 45.7 kg) and 12 healthy volunteers (LBM = 50.0 kg) received a single 10-min intravenous infusion of 2 g cefpirome. Plasma and urine concentrations were determined by high-performance liquid chromatography (HPLC). Population PK and Monte Carlo simulations were performed using NONMEM and S-ADAPT and a duration of an unbound plasma concentration above the MIC ≥ 65% of the dosing interval as a pharmacodynamic target. Unscaled clearances for CF patients were similar to those seen with healthy volunteers, and the volume of distribution was 6% lower for CF patients. Linear scaling of total clearance by WT resulted in clearance that was 20% higher (P≤ 0.001 [nonparametric bootstrap]) in CF patients. Allometric scaling by LBM explained the differences between the two subject groups with respect to average clearance and volume of distribution and reduced the unexplained between-subject variability of renal and nonrenal clearance by 10 to 14%. For the CF patients, robust (>90%) probabilities of target attainment (PTA) were achieved by the administration of a standard dose of 2 g/70 kg WT every 12 h (Q12h) given as 30-min infusions for MICs ≤ 1.5 mg/liter. As alternative dosage regimens, a 5-h infusion of 1.33 g/70 kg WT Q8h achieved robust PTAs for MICs ≤ 8 to 12 mg/liter and a continuous infusion of 4 g/day for MICs ≤ 12 mg/liter. Prolonged infusion of cefpirome is expected to be superior to short-term infusions for MICs between 2 and 12 mg/liter.


Perfusion ◽  
2021 ◽  
pp. 026765912110506
Author(s):  
Nicholas J Vollmer ◽  
Erica D Wittwer ◽  
Andrew N Rosenbaum ◽  
Patrick M Wieruszewski

Procainamide is a useful agent for management of ventricular arrhythmia, however its disposition and appropriate dosing during extracorporeal membrane oxygenation (ECMO) is unknown. We report experience with continuous procainamide infusion in a critically ill adult requiring venoarterial ECMO for incessant ventricular tachycardia. Pharmacokinetic analysis of procainamide and its metabolite, N-acetylprocainamide (NAPA), was performed using serum and urine specimens. Kidney function was preserved, and sequencing of the N-acetyltransferase 2 gene revealed the patient was a phenotypic slow acetylator. Procainamide volume of distribution and half-life were calculated and found to be similar to healthy individuals. However, despite elevated serum procainamide concentrations, NAPA concentrations remained far lower in the serum and urine. The magnitude of procainamide and NAPA discordance suggested alternative contributors to the deranged pharmacokinetic profile, and we hypothesized NAPA sequestration by the ECMO circuit. Ultimately, the patient received orthotopic cardiac transplantation and was discharged home in stable condition. Procainamide should be used cautiously during ECMO, with close therapeutic drug monitoring of serum procainamide and NAPA concentrations. The achievement of therapeutic NAPA concentrations while maintaining safe serum procainamide concentrations during ECMO support may be challenging.


PEDIATRICS ◽  
1974 ◽  
Vol 54 (6) ◽  
pp. 670-672
Author(s):  
Alan K. Done

Clinicians may, at first glance, wonder why the paper in this issue by Levy and Yaffe1 on the volume of distribution of salicylate in children should concern them or, indeed, why it even appears in their journal. This important and excellent study is a prime example of the growing influence and involvement of clinical pharmacology and pharmacokinetics in medicine generally and pediatrics particularly. Already substantial, with the growing complexity of pediatric therapeutics, this relationship stands to become even more widespread and intense as a result of increasing emphasis on more and better pediatric drug studies. Evolving ethical-legal constraints notwithstanding,2 these must and will expand.


1997 ◽  
Vol 41 (10) ◽  
pp. 2201-2208 ◽  
Author(s):  
A Adedoyin ◽  
J F Bernardo ◽  
C E Swenson ◽  
L E Bolsack ◽  
G Horwith ◽  
...  

Amphotericin B (AmB) has been the most effective systemic antifungal agent, but its use is limited by the dose-limiting toxicity of the conventional micellar dispersion formulation (Fungizone). New formulations with better and improved safety profiles are being developed and include ABELCET (formerly ABLC), but their dispositions have not been well characterized; hence, the reason for their improved profiles remains unclear. This report details the pharmacokinetics of ABELCET examined in various pharmacokinetic and efficacy studies by using whole-blood measurements of AmB concentration performed by high-pressure liquid chromatography. The data indicated that the disposition of AmB after administration of ABELCET is different from that after administration of Fungizone, with a faster clearance and a larger volume of distribution. It exhibits complex and nonlinear pharmacokinetics with wide interindividual variability, extensive distribution, and low clearance. The pharmacokinetics were unusual. Clearance and volume of distribution were increased with dose, peak and trough concentrations after multiple dosings increased less than proportionately with dose, steady state appeared to have been attained in 2 to 3 days, despite an estimated half-life of up to 5 days, and there was no evidence of significant accumulation in the blood. The data are internally consistent, even though they were gathered under different conditions and circumstances. The pharmacokinetics of ABELCET suggest that lower concentrations in blood due to higher clearance and greater distribution may be responsible for its improved toxicity profile compared to those of conventional formulations.


2019 ◽  
Vol 67 (4) ◽  
pp. 602-609
Author(s):  
Mohamed Aboubakr ◽  
Ahmed Soliman

The plasma pharmacokinetics of danofloxacin was studied in healthy African catfish (Clarias gariepinus) following a single intravenous (IV) and intramuscular (IM) administration of 10 mg/kg at 22 °C. Catfish were divided into two groups (each group containing 78 fish), then danofloxacin mesylate (10 mg/kg) was administered IV (into the caudal vein) in Group 1 and IM (into the right epaxial muscle) in Group 2, and blood was obtained from the caudal vein before (0 h) and after (0.25, 0.5, 1, 2, 4, 8, 12, 24, 36, 48, 72 and 96 h) of drug administration. High-performance liquid chromatography was used for the determination of plasma concentration, and a non-compartmental model was used for the analysis of pharmacokinetic parameters. After IV administration, elimination half-life (t1/2λz, 24.49 h), mean residence time (MRT, 30.14 h), volume of distribution at steady state (Vdss, 1.07 L/kg) and total body clearance (CLT, 0.035 L/h/kg) were determined. After IM administration, t1/2λz, MRT, peak concentration (Cmax), time to reach Cmax and bioavailability were 47.64 h, 61.06 h, 5.22 µg/mL, 1 h and 67.12%, respectively. After IM administration, danofloxacin showed good bioavailability and long t1/2λz. The favourable pharmacokinetic characteristics after IM administration support the use of danofloxacin for the treatment of susceptible bacterial infections in catfish.


2013 ◽  
Vol 57 (12) ◽  
pp. 6246-6253 ◽  
Author(s):  
Eric M. Mucker ◽  
Arthur J. Goff ◽  
Joshua D. Shamblin ◽  
Douglas W. Grosenbach ◽  
Inger K. Damon ◽  
...  

ABSTRACTNaturally occurring smallpox has been eradicated but remains a considerable threat as a biowarfare/bioterrorist weapon (F. Fleck, Bull. World Health Organ.81:917–918, 2003). While effective, the smallpox vaccine is currently not recommended for routine use in the general public due to safety concerns (http://www.bt.cdc.gov/agent/smallpox/vaccination). Safe and effective countermeasures, particularly those effective after exposure to smallpox, are needed. Currently, SIGA Technologies is developing the small-molecule oral drug, tecovirimat (previously known as ST-246), as a postexposure therapeutic treatment of orthopoxvirus disease, including smallpox. Tecovirimat has been shown to be efficacious in preventing lethal orthopoxviral disease in numerous animal models (G. Yang, D. C. Pevear, M. H. Davies, M. S. Collett, T. Bailey, et al., J. Virol.79:13139–13149, 2005; D. C. Quenelle, R. M. Buller, S. Parker, K. A. Keith, D. E. Hruby, et al., Antimicrob. Agents Chemother.,51:689–695, 2007; E. Sbrana, R. Jordan, D. E. Hruby, R. I. Mateo, S. Y. Xiao, et al., Am. J. Trop. Med. Hyg.76:768–773, 2007). Furthermore, in clinical trials thus far, the drug appears to be safe, with a good pharmacokinetic profile. In this study, the efficacy of tecovirimat was evaluated in both a prelesional and postlesional setting in nonhuman primates challenged intravenously with 1 × 108PFU ofVariola virus(VARV; the causative agent of smallpox), a model for smallpox disease in humans. Following challenge, 50% of placebo-treated controls succumbed to infection, while all tecovirimat-treated animals survived regardless of whether treatment was started at 2 or 4 days postinfection. In addition, tecovirimat treatment resulted in dramatic reductions in dermal lesion counts, oropharyngeal virus shedding, and viral DNA circulating in the blood. Although clinical disease was evident in tecovirimat-treated animals, it was generally very mild and appeared to resolve earlier than in placebo-treated controls that survived infection. Tecovirimat appears to be an effective smallpox therapeutic in nonhuman primates, suggesting that it is reasonably likely to provide therapeutic benefit in smallpox-infected humans.


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