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Angelo Paci

Publications and source records attributed to Angelo Paci.

14 recordsLinked to original sources
PubMed2006

Induction of glutathione synthesis explains pharmacodynamics of high-dose busulfan in mice and highlights putative mechanisms of drug interaction.

Busulfan is an example of a drug eliminated through glutathione S-transferase (GST)-catalyzed conjugation with reduced glutathione (GSH). We studied the pharmacokinetics and toxicity of busulfan in C57BL6 mice in correlation with liver GST activity and GSH synthesis by accurate determination of precursors, namely, gamma-glutamyl-cysteine and cysteine. A significantly lower incidence of acute toxicity was observed in mice receiving busulfan 16.5 mg/kg twice a day compared with animals receiving 33 mg/kg once a day. In both cases, a total dose of 132 mg/kg was administered over 4 days. The difference in toxicity was explained by pharmacokinetics since a strong induction of clearance was observed only in animals treated twice daily. Induction of metabolism was correlated with an increase in liver cysteine content and enhanced glutathione synthesis rate, whereas GST activity was unchanged. To our knowledge, this is the first time that in vivo flux of GSH synthesis has been shown to be closely related to a drug plasma clearance and toxicity. These results allow hypothesizing that GSH liver synthesis may directly influence busulfan clearance in humans with possible implications in the occurrence of hepatic veno-occlusive disease.

Animals↗
PubMed2006

Pharmacokinetics, metabolism, and routes of excretion of intravenous irofulven in patients with advanced solid tumors.

Irofulven is currently in Phase 2 clinical trials against a wide variety of solid tumors and has demonstrated activity in ovarian, prostate, gastrointestinal, and non-small cell lung cancer. The objectives of this study were to determine its pharmacokinetics and route of excretion and to characterize its metabolites in human plasma and urine samples after a 30-min i.v. infusion at a dose of 0.55 mg/kg in patients with advanced solid tumors. Three patients were administered i.v. 100 microCi of [14C]irofulven over a 30-min infusion on day 1 of cycle 1. Serial blood and plasma samples were drawn at 0 (before irofulven infusion) and up to 144 h after the start of infusion. Urine and fecal samples were collected for up to 144 h after the start of infusion. The mean urinary and fecal excretion of radioactivity up to 144 h were 71.2 and 2.9%, respectively, indicating renal excretion was the major route of elimination of [14C]irofulven. The C(max), AUC(0-infinity), and terminal half-life values for total radioactivity were 1130 ng-Eq/ml, 24,400 ng-Eq . h/ml, and 116.5 h, respectively, and the corresponding values for irofulven were 82.7 ng/ml, 65.5 ng . h/ml, and 0.3 h, respectively, suggesting that the total radioactivity in human plasma was a result of the metabolites. Twelve metabolites of irofulven were detected in human urine and plasma by electrospray ionization/tandem mass spectrometry. Among these metabolites, the cyclopropane ring-opened metabolite (M2) of irofulven was found, and seven others were proposed as glucuronide and glutathione conjugates.

Antineoplastic Agents, Alkylating↗
PubMed2006

Application of an acceptance sampling plan for post-production quality control of chemotherapeutic batches in an hospital pharmacy.

BACKGROUND: About 26,000 chemotherapeutic batches were produced in 2003 in the Institute Gustave Roussy and 83% were qualitatively and quantitatively assessed in post-production controls via an analytical platform. The rate of non-conformity (outside the specification limits of the target concentration +/-10%) decreased from 8.9% to 2.2% between years 2001 and 2003. A cost- and time-saving acceptance sampling plan was applied to assay fewer batches whilst maintaining an accurate estimate of the quality level. METHODS: The opportunity to apply a single sampling plan by attributes with an acceptance quality level of 2.2% was evaluated. A prognostic study using a logistic regression model was performed for some drugs to identify risk factors associated with the non-conformity rate of preparations. RESULTS: Out of 26 drugs, 17 have not been sampled, since they were prepared less than 400 times per year. For six drugs, a reduction of about 50% in the number of assays was estimated. Three drugs were "at risk" of being non-conform: for these drugs, all batches were analysed. CONCLUSIONS: The sampling plan allowed a reduction of almost 8000 analyses with respect to the number of batches analysed for 6 drugs. For the 3 drugs with the higher risk to be non-conform, associated risk factors were identified to set up corrective actions.

Antineoplastic Agents↗
PubMed2006

Liquid chromatography-tandem mass spectrometry assay of reduced and oxidized glutathione and main precursors in mice liver.

A liquid chromatography/tandem mass spectrometry assay of glutathione (GSH), glutathione disulfide (GSSG) and of precursors (gamma-glutamyl-cysteine, cysteinyl-glycine, cysteine, cystine, homocysteine and homocystine) was developed to study glutathione synthesis in mice liver. After iodoacetic acid derivatization, the analytes were analyzed using reversed-phase gradient HPLC and detected using multiple reaction monitoring. Linear calibrations were performed over the concentrations range of 100-10,000 ng/mL for the thiol-containing precursors and extended up to 100,000 ng/mL for GSH and GSSG. The method was validated for each compound with inter-day accuracy below 11.9% and with precision below 15%. The method showed low limits of quantitation of 100 ng/mL for each thiol-containing compound and GSSG and of 200 ng/mL for other disulfides.

Animals↗
PubMed2006

Microbiological and physicochemical stability of fentanyl and sufentanil solutions for patient-controlled delivery systems.

The aim of this study was to assess the microbiological and physicochemical stability of opioid solutions containing fentanyl or sufentanil and thereby determine the feasibility of extending the expiration dates after mixing. Five systems containing fentanyl or sufentanil solutions at 50 microg/mL in portable patient-controlled analgesia (PCA) systems were filled and stored at room temperature for 14 days. They were sampled immediately after preparation, at day 3, and each day of the following weeks. Microbiological stability was assessed by performing sterility tests. The physicochemical study was performed by determining aspect, pH, and osmolality evolution. All samples were tested for appearance, change in color, and loss of concentration using an analytical method. There was no significant change in pH and osmolality values of any solutions. No precipitation or change in color was observed in any of the sample solutions. There was no significant loss of fentanyl or sufentanil over 14 days (4.3% and 4.1%, respectively). This study indicates that both drug solutions in the PCA systems are stable for a minimum of 14 days at room temperature.

Analgesia, Patient-Controlled↗
PubMed2005

Fluorescence detection combined with either HPLC or HPTLC for pharmaceutical quality control in a hospital chemotherapy production unit: application to camptothecin derivatives.

In order to achieve the analytical assessment of the manufactured batches of chemotherapy preparations, post-production quality control has been developed. The common use of camptothecin derivatives (i.e. irinotecan (CPT-11) and topotecan (TPT)) as part of protocols in Institut Gustave Roussy (IGR) has led to develop an efficient analytical method that could assess an increasing number of samples with high throughput, good specificity and practicality. Due to the difference of concentration between batches containing irinotecan or topotecan, HPLC and HPTLC both combined with fluorescence detection were investigated. Those two techniques made identity, purity and quantitation assays possible. The chromatographic conditions that were chosen allowed identification of each drug through their rate of flow (Rf), 0.10 and 0.35, or their retention time (tR), 2 and 7 min for topotecan and irinotecan, respectively. A calibration curve was plotted for each molecule and validated by three quality controls (high, medium and low). Coefficients of variation of repeatability (CVr) and intermediate precision (CVi) were determined for both methods. Considering their values and the concentration ranges (from 100 to 500 mg/L for HPTLC and from 0.1 to 1 mg/L for HPLC), it was decided to perform analysis using HPTLC for irinotecan preparations and HPLC for topotecan preparations. These inferences seemed appropriate regarding the number of preparations to be assayed.

Antineoplastic Agents↗
PubMed2005

Quality control and stability study using HPTLC: applications to cyclophosphamide in various pharmaceutical products.

Cyclophosphamide is an alkylating agent widely used from cancer chemotherapy to immunotherapy purposes. In paediatrics oncology, oral cyclophosphamide prescribed at low dosages for a long time treatment is currently investigated. This treatment is a putative well tolerated regimen for children treated for a wide variety of recurrent solid tumours. For these purposes, new oral formulations more convenient for children than cyclophosphamide 50mg tablets are needed. Thus, we present a rapid method for the assay of cyclophosphamide in various pharmaceutical preparations using high-performance thin-layer chromatography (HPTLC) and derivatization with phosphomolybdic acid. This method is accurate and precise and allows quantitation of cyclophosphamide in aqueous solutions from 400 to 1200 microg/mL. It is suitable for quantitation and stability studies of cyclophosphamide in pharmaceutical products, i.e. capsules and infusion bags prepared in a hospital pharmacy. According to pharmaceutical guidelines, we demonstrated that low dose cyclophosphamide capsules, extemporaneously prepared for children, are stable at least for 70 days.

Calibration↗
PubMed2005

Liquid chromatography-mass spectrometry assay for quantitation of ifosfamide and its N-deschloroethylated metabolites in rat microsomal medium.

A specific and sensitive quantitative assay has been developed using high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) for the simultaneous quantitation of the antitumor drug ifosfamide (IFM) and its two metabolites, N2-deschloroethylifosfamide (N2-DCE-IFM) and N3-deschloroethylifosfamide (N3-DCE-IFM) in microsomal medium. The analytes and the internal standard (cyclophosphamide) were isolated by ethylacetate extraction from rat liver microsomes. They were analysed on a Nucleosil C18 HD column (125 mm x 4 mm, 5 microm) using a step gradient with the mobile phase (2 mM ammonium formate and methanol). The HPLC-ESI-MS method used selected ion monitoring of ions m/z 199.1 Th and m/z 261.1 Th and was validated in the concentrations ranges of 100-5000 ng/mL for IFM and 50-2500 ng/mL for its N-deschloroethylated metabolites (DCE-IFM) with good accuracy and precision (CV less than 15%). The low limits of quantitation (LLOQ) were found at 50 ng/mL for N-deschloroethylated metabolites and at 100 ng/mL for the parent drug (IFM). The method was applied for the determination of ifosfamide and its N-deschloroethylated metabolites in rat microsomal incubations.

Animals↗
PubMed2005

In vitro echogenicity characterization of poly[lactide-coglycolide] (plga) microparticles and preliminary in vivo ultrasound enhancement study for ultrasound contrast agent application.

OBJECTIVES: This work includes (1) the characterization of a reproducible poly[lactide-coglycolide] (PLGA) microparticle preparation with an optimial mean diameter and size distribution and (2) the preliminary in vivo ultrasonographic investigation of PLGA microparticles. METHODS: A first series of PLGA microparticle preparations (1 to 15 mum) was acoustically characterized on a hydrodynamic device to select the most appropriate for ultrasound contrast agent application. Preparations of 3-microm microparticles were selected, characterized at different doses, and then injected into 20 melanoma grafted mice for contrast-enhanced power Doppler ultrasonography evaluation. RESULTS: The 3-microm microparticles (3.26-microm mean diameter with 0.41-microm standard deviation) led to in vitro enhancement of 18.3 dB at 0.62 mg/mL. In vivo experiments showed 47% enhancement of intratumoral vascularization detection after PLGA injection, significantly correlated (P < 0.0001) with preinjection intravascularization and tumoral volume. No toxicity was histologically observed. CONCLUSION: The 3-microm PLGA microparticles provided significant enhancement in vitro and in vivo without any toxicity.

Animals↗
PubMed2005

Microbial growth tests in anti-neoplastic injectable solutions.

The Institut Gustave-Roussy (IGR) Department of Clinical Pharmacy (DCP) ensures the annual preparation of about 30 000 therapeutic batches of anti-neoplastic agents. High performance thin-layer chromatography (HPTLC) allows postproduction quality control of these batches. Although the centralized chemotherapy manufacturing unit has been recently ISO 9001:2000 certified, it was considered to improve the quality level of manufactured batches even further. The viability of micro-organisms (bacteria and fungi) in appropriate sterile media containing various anti-neoplastic agents at therapeutic concentration was assessed to demonstrate the lack of contamination during our manufacturing process in the isolator. After 14 days of incubation in these media, the results show the absence of contamination of the manufactured batches. This leads us to conclude that using sterile drugs and sterile medical devices in a sterile isolator allows the manufacture of sterile therapeutic batches with excellent confidence.

Antimetabolites, Antineoplastic↗
PubMed2004

Incidence of renal insufficiency in cancer patients and evaluation of information available on the use of anticancer drugs in renally impaired patients.

BACKGROUND: Chronic renal failure is a common pathology. The high frequency of this disease in the general US population has been assessed in the NHANES III study. However, the frequency of chronic renal insufficiency among cancer patients remains unclear. MATERIAL/METHODS: 316 cancer patients were in a one-month study, included regardless of their pathology, treatment (antineoplastic drugs used or programmed to be used, pretreated, or no treatment), or any other criteria. RESULTS: Among the patients, 287 (90.8%) had normal serum creatinine levels (<110 micromol/l), i.e. a frequency of 9.2% for renal insufficiency in our population. However, when renal function was estimated by calculating creatinine clearance using the Cockcroft and Gault formula, 33% of the patients had an estimated GFR of less than 80 ml/min. Among these, 28% had a creatinine clearance ranging form 80 to 50 ml/min and 5% had a creatinine clearance of less than 50 ml/min. Renal insufficiency is frequent in cancer patients since almost one third of the patients present renal insufficiency. Furthermore, among patients with normal serum creatinine levels, one patient out of five has asymptomatic renal insufficiency. CONCLUSIONS: Therefore, it is of major importance that renal function be assessed by calculation of creatinine clearance using the Cockcroft and Gault formula in every patient, even when serum creatinine is within the normal range.

Aged↗
PubMed2004

High-performance thin-layer chromatography with a derivatization procedure, a suitable method for the identification and the quantitation of busulfan in various pharmaceutical products.

Busulfan is an alkylating agent widely used in combination chemotherapy regimens followed by allogeneic or autologous hematopoietic stem cell transplantation (HSCT). We present a rapid method for assaying busulfan in pharmaceutical preparations using high-performance thin-layer chromatography (HPTLC) and derivatization with 4-nitrobenzylpyridine. The method is accurate and precise and allows quantitation of busulfan in aqueous solutions from 100 to 500 microg/ml. It is suitable for identification. quantitation and stability studies of busulfan in pharmaceutical products, i.e. capsules or infusion bags prepared in a hospital pharmacy.

Busulfan↗
PubMed2003

Contribution of high-performance thin-layer chromatography to a pharmaceutical quality assurance programme in a hospital chemotherapy manufacturing unit.

The Department of Clinical Pharmacy (DCP) in the Institut Gustave-Roussy (IGR) is equipped with a high-performance thin-layer chromatography (HPTLC) analytical platform. One of the numerous possible uses of HPTLC is post-production quality control of chemotherapy manufacturing. After 3 years of existence, routine validation of manufactured batches has attained considerable maturity: 24 cytotoxic agents can be controlled in terms of identity, purity and concentration. Approximately 50% of the sampled preparations are assessed. More than 97% were within specifications, 1.6% were not, probably due to incorrect homogenization before sampling; and 1% were not evaluable. Using HPTLC in a hospital manufacturing unit contributes to quality assurance programmes such as accreditation to which the IGR DCP is now committed but also ISO 9001:2000 certification concerning the chemotherapy manufacturing unit.

Chromatography, High Pressure Liquid↗