Modified high-performance liquid chromatographic method for the determination of ganciclovir in plasma from patients with severe renal impairment

Ganciclovir

Ganciclovir is synthetic nucleoside analog of guanine closely related to acyclovir but has greater activity against cytomegalovirus. This comprehensive profile on ganciclovir starts with a description of the drug: nomenclature, formulae, chemical structure, elemental composition, and appearance. The uses and application of the drug are explained. The methods that were used for the preparation of ganciclovir are described and their respective schemes are outlined. The methods which were used for the physical characterization of the dug are: ionization constant, solubility, X-ray powder diffraction pattern, crystal structure, melting point, and differential scanning calorimetry. The chapter contains the spectra of the drug: ultraviolet spectrum, vibrational spectrum, nuclear magnetic resonance spectra, and the mass spectrum. The compendial methods of analysis of ganciclovir include the United States Pharmacopeia methods. Other methods of analysis that were reported in the literature include: high-performance liquid chromatography alone or with mass spectrometry, electrophoresis, spectrophotometry, voltammetry, chemiluminescence, and radioimmunoassay. Biological investigation on the drug includes: pharmacokinetics, metabolism, bioavailability, and biological analysis. Reviews on the methods used for preparation or for analysis of the drug are provided. The stability of the drug in various media and storage conditions is reported. More than 240 references are listed at the end of the chapter.

2016 White Paper on recent issues in bioanalysis: focus on biomarker assay validation (BAV) (Part 1 - small molecules, peptides and small molecule biomarkers by LCMS)

The 2016 10^th Workshop on Recent Issues in Bioanalysis (10^th WRIB) took place in Orlando, Florida with participation of close to 700 professionals from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations, and regulatory agencies worldwide. WRIB was once again a 5-day, weeklong event - A Full Immersion Week of Bioanalysis including Biomarkers and Immunogenicity. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small and large molecule analysis involving LCMS, hybrid LBA/LCMS, and LBA approaches, with the focus on biomarkers and immunogenicity. This 2016 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. This white paper is published in 3 parts due to length. This part (Part 1) discusses the recommendations for small molecules, peptides and small molecule biomarkers by LCMS. Part 2 (Hybrid LBA/LCMS and regulatory inputs from major global health authorities) and Part 3 (large molecule bioanalysis using LBA, biomarkers and immunogenicity) will be published in the Bioanalysis journal, issue 23.

Ganciclovir in solid organ transplant recipients: is there a role for clinical pharmacokinetic monitoring?

The authors use a previously published decision-making algorithm to address the role of clinical pharmacokinetic monitoring of ganciclovir, the drug of choice for prophylaxis and treatment of cytomegalovirus (CMV) in solid organ transplant recipients. Ganciclovir pharmacokinetics have been studied in solid organ transplant recipients with a wide range of peak and trough concentrations reported. Numerous assays are available to measure plasma concentrations of ganciclovir, but no clear correlation has been established between peak or trough concentrations and either efficacy or toxicity of the drug. For patients receiving treatment, the pharmacological response of ganciclovir is assessed initially by clinical response. Monitoring prophylactic therapy in asymptomatic patients poses a greater challenge. Although monitoring of antigenemia or polymerase chain reaction (PCR) deoxyribonucleic acid (DNA) is not yet part of routine clinical practice, studies have shown a role for these techniques in monitoring response to antiviral therapy. Studies of subpopulations of renal failure patients show a prolonged ganciclovir half-life that requires dosage adjustments. However, ganciclovir clearance is closely correlated with creatinine clearance, which is an appropriate approach to adjusting dosages. Studies in pediatric patients also demonstrate a close correlation between dose per kilogram and AUC, suggesting that monitoring of ganciclovir levels may not be necessary. Based on the evidence presented in this review, routine clinical pharmacokinetic monitoring of ganciclovir does not appear to be warranted in solid organ transplant recipients.

A rapid and sensitive method for the quantification of ganciclovir in plasma using liquid chromatography/selected reaction monitoring/mass spectrometry

A method using reversed-phase liquid chromatography coupled with electrospray ionization and selected reaction monitoring mass spectrometry has been developed for the quantitative analysis of ganciclovir in rat plasma. Acyclovir, a structurally related analog of ganciclovir, was used as the internal standard. A small volume of plasma (50 microL) was spiked with the internal standard and plasma proteins were precipitated by methanol. The supernatant was dried under nitrogen, and then reconstituted in water. The use of liquid chromatography/selected reaction monitoring/mass spectrometry effectively eliminated potential interference from endogenous constituents in the plasma. This highly selective and sensitive method made it possible to analyze plasma ganciclovir with a lower limit of quantitation of 10 ng/mL. The assay was reproducible and linear in the range 10-10,000 ng/mL. The precision and accuracy values were in the range 2.0-6.9% and 89.0-109.6%, respectively. The analyte recovery was greater than 88%. This method was successfully used to monitor the pharmacokinetic profile of ganciclovir in normal rats following intraperitoneal administration of the drug.

Development and validation of a sensitive method for the determination of ganciclovir in human plasma samples by reversed-phase high-performance liquid chromatography

A rapid, sensitive, specific liquid chromatographic method has been developed for the determination of therapeutic levels of ganciclovir in human plasma. Plasma (1 ml) and acyclovir (I.S.) were treated with 50% trichloroacetic acid. The supernatant was neutralized with 2 M NaOH and purified with chloroform. The aqueous phase (80 microl) was analyzed by a 3-microm Hypersil ODS C18 column with 0.04 M triethylamine-0.1 M sodium dihydrogen phosphate monohydrate as the mobile phase (1 ml/min) and ultraviolet detection at 254 nm. Calibration was linear from 50 to 10000 ng/ml. Intra- and inter-day C.V. did no exceed 6.65%. The detection limit was about 10 ng/ml.

High-performance liquid chromatographic determination of ganciclovir nucleotides in human myocardial tissue

A method for the analysis of ganciclovir nucleotides in myocardial tissues was developed. The antiviral effect of ganciclovir is attributed to intracellular ganciclovir nucleotides. The procedure is based on perchloric acid deproteinization and enzymatic hydrolysis of the ganciclovir nucleotides to ganciclovir. Then, the parent drug was analyzed on a Hypersil ODS column using potassium dihydrogenphosphate buffer as mobile phase. The mean analytical recovery of ganciclovir from myocardial tissue was 101 +/- 2% and the detection limit was 2 pmol. The sample treatment procedure described is simple and presents a suitable analytical tool for the investigation of the ganciclovir nucleotides pool in tissues.