1
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Sabirova Z, Mahnoor S, Lasfar D, Gagné V, Théorêt Y, Leclerc JM, Laverdière C, Sinnett D, Tran TH, Krajinovic M. Novel variant in Nudix hydrolase 15 gene influences 6-mercaptopurine toxicity in childhood acute lymphoblastic leukemia patients. Pharmacogenet Genomics 2024:01213011-990000000-00059. [PMID: 38682355 DOI: 10.1097/fpc.0000000000000533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
Acute lymphoblastic leukemia (ALL) is the most frequent pediatric cancer. 6-Mercaptopurine (6-MP) is a key component of ALL treatment. Its use, however, is also associated with adverse drug reactions, particularly myelosuppression. Thiopurine S-methyltransferase (TPMT) and, more recently, Nudix hydrolase 15 (NUDT15) deficiency, due to no-function variants in their respective genes, are well known for their role in the development of this toxicity. Two novel genetic variants, rs12199316 in TPMT and rs73189762 in the NUDT15 gene, were recently identified by targeted sequencing. The latter is particularly interesting because of its potential association with 6-MP intolerance. Here, we assessed the relationship of this variant with the risk of myelosuppression and 6-MP dose intensity in 275 patients treated with Dana Farber Cancer Institute ALL protocols at the Sainte Justine University Health Center. Carriers of the NUDT15 rs73189762 variant allele were at a higher risk of myelosuppression, as shown by absolute phagocyte count reduction during consolidation II and maintenance phases of therapy. Reduction in 6-MP dose intensity was observed in patients with both rs73189762 and known no-function variants in the NUDT15 and TPMT genes. This finding supports the initial observation and suggests that 6-MP dose reduction might be beneficial for individuals with this genotype combination.
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Affiliation(s)
- Zarina Sabirova
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal
- CHU Sainte-Justine Research Center
| | - Shazia Mahnoor
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal
| | - Dina Lasfar
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal
| | | | - Yves Théorêt
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal
- CHU Sainte-Justine Research Center
| | - Jean Marie Leclerc
- CHU Sainte-Justine Research Center
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
| | - Caroline Laverdière
- CHU Sainte-Justine Research Center
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
| | - Daniel Sinnett
- CHU Sainte-Justine Research Center
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
| | - Thai-Hoa Tran
- CHU Sainte-Justine Research Center
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
| | - Maja Krajinovic
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal
- CHU Sainte-Justine Research Center
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
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2
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Piché-Renaud PP, Chiasson CO, Autmizguine J, Ovetchkine P, Lachance C, Théorêt Y, Martin B. Treatment of Congenital Cytomegalovirus and Ganciclovir Therapeutic Drug Monitoring in Twin Preterm Infants. J Pediatr Pharmacol Ther 2023; 28:93-101. [PMID: 36777981 PMCID: PMC9901313 DOI: 10.5863/1551-6776-28.1.93] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/18/2022] [Indexed: 02/05/2023]
Abstract
Congenitally acquired cytomegalovirus (CMV) infection is the most prevalent congenital infection worldwide and the most frequent cause of acquired sensorineural hearing loss. The burden of the disease is even more important in premature and very low birth weight infants. However, few data exist on the treatment with intravenous ganciclovir and oral valganciclovir in this vulnerable population. We report the case of twins congenitally infected with CMV and born prematurely at 27 weeks' gestation. Treatment regimens were initially individualized for their prematurity and renal function, and then adjusted with therapeutic drug monitoring (TDM) to adapt to their continuously evolving physiologic maturation. As infants were aging, the plasmatic half-life of ganciclovir slowly decreased to term infant values around 10 weeks of chronological age, or 37 weeks of postmenstrual age. Results for blood polymerase chain reaction tests became negative and long-term follow-ups were satisfactory in both twins. The limited data for infants born before 32 weeks of gestation or at less than 1200 g and evolution of ganciclovir pharmacokinetic parameters justify the use of TDM in these settings.
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Affiliation(s)
| | | | - Julie Autmizguine
- Service of Infectious Disease (JA, PO), CHU Sainte-Justine, Montréal, Québec,Department of Clinical Pharmacology Unit (JA, YT), CHU Sainte-Justine, Montréal, Québec,Department of Pharmacology and Physiology (JA), Université de Montréal, Montréal, Québec
| | - Philippe Ovetchkine
- Service of Infectious Disease (JA, PO), CHU Sainte-Justine, Montréal, Québec
| | | | - Yves Théorêt
- Department of Clinical Pharmacology Unit (JA, YT), CHU Sainte-Justine, Montréal, Québec
| | - Brigitte Martin
- Department of Pharmacy (COC, BM), CHU Sainte-Justine, Montréal, Québec
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3
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Joly JA, Vallée A, Bourdin B, Bourbonnais S, Patey N, Gaboury L, Théorêt Y, Decaluwe H. Combined IFN-γ and JAK inhibition to treat hemophagocytic lymphohistiocytosis in mice. J Allergy Clin Immunol 2023; 151:247-259.e7. [PMID: 35973477 DOI: 10.1016/j.jaci.2022.07.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 07/26/2022] [Accepted: 07/29/2022] [Indexed: 02/04/2023]
Abstract
BACKGROUND Familial hemophagocytic lymphohistiocytosis is a life-threatening hyperinflammatory disease caused by genetic defects in the granule-mediated cytotoxic pathway. Success of hematopoietic cell transplantation, the only cure, is correlated with the extent of disease control before transplantation. Unfortunately, disease refractoriness and toxicities to standard chemotherapy-based regimens are fatal in a fraction of patients. Novel targeted immunotherapies, such as IFN-γ blocking antibodies or ruxolitinib, a Janus kinase (JAK) 1/2 inhibitor, are promising but only partially effective at controlling disease. OBJECTIVE We asked whether combinations of cytokine-targeted therapies, using antibodies or JAK inhibitor, work synergistically to counteract HLH. METHODS Genetically predisposed mice were infected and treated with distinct combinations of immunotherapies. Disease outcome was monitored and compared to monotherapies. RESULTS We showed that inhibiting IL-6 or IL-18 signaling in combination with IFN-γ blockade or ruxolitinib did not increase disease control compared to anti-IFN-γ antibodies or ruxolitinib monotherapies. In contrast, clinically relevant doses of ruxolitinib combined with low doses of anti-IFN-γ blocking antibodies corrected cytopenias, prevented overt neutrophilia, limited cytokinemia, and resolved HLH immunopathology and symptomatology. CONCLUSIONS Our findings demonstrate that IFN-γ blockade and ruxolitinib act synergistically to suppress HLH progression. This supports the use of combined cytokine-targeted therapies as a bridge to hematopoietic cell transplantation in severe familial hemophagocytic lymphohistiocytosis.
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Affiliation(s)
- Josée-Anne Joly
- Cytokines and Adaptive Immunity Laboratory, Sainte-Justine University Hospital Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Alexis Vallée
- Cytokines and Adaptive Immunity Laboratory, Sainte-Justine University Hospital Research Center, Université de Montréal, Montréal, Québec, Canada; Department of Microbiology, Infectiology and Immunology, Université de Montréal, Montréal, Québec, Canada
| | - Benoîte Bourdin
- Cytokines and Adaptive Immunity Laboratory, Sainte-Justine University Hospital Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Sara Bourbonnais
- Cytokines and Adaptive Immunity Laboratory, Sainte-Justine University Hospital Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Natalie Patey
- Department of Pathology and Cellular Biology, Université de Montréal, Montréal, Québec, Canada
| | - Louis Gaboury
- Department of Pathology and Cellular Biology, Université de Montréal, Montréal, Québec, Canada; Histology and Molecular Pathology Research Unit, Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montréal, Québec, Canada
| | - Yves Théorêt
- Department of Pharmacology and Physiology, Université de Montréal, Montréal, Québec, Canada
| | - Hélène Decaluwe
- Cytokines and Adaptive Immunity Laboratory, Sainte-Justine University Hospital Research Center, Université de Montréal, Montréal, Québec, Canada; Department of Microbiology, Infectiology and Immunology, Université de Montréal, Montréal, Québec, Canada; Department of Pediatrics, Université de Montréal, Montréal, Québec, Canada.
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4
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Andelfinger G, Zenker M, Norrish G, Russell M, Meisner J, Peng D, Prendiville T, Kleinmahon J, Kantor P, Sen DG, Human D, Ewert P, Krueger M, Reber D, Donner B, Hart C, Odri-Komazec I, Rupp S, Hahn A, Hanser A, Hofbeck M, Draaisma J, Udink ten Cate F, Mussa A, Ferrero G, Vaujois L, Raboisson M, Delrue M, Marquis C, Théorêt Y, Kaski J, Gelb B, Wolf C. MAPK AND AKT/MTOR INHIBITION IMPROVES CHILDHOOD RASOPATHY-ASSOCIATED CARDIOMYOPATHY. Can J Cardiol 2022. [DOI: 10.1016/j.cjca.2022.08.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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5
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Remy A, Tran TH, Dubois J, Gavra P, Lapointe C, Winikoff R, Facundo GB, Théorêt Y, Kleiber N. Repurposing alpelisib, an anti-cancer drug, for the treatment of severe TIE2-mutated venous malformations: Preliminary pharmacokinetics and pharmacodynamic data. Pediatr Blood Cancer 2022; 69:e29897. [PMID: 35876545 DOI: 10.1002/pbc.29897] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 06/23/2022] [Accepted: 07/05/2022] [Indexed: 11/09/2022]
Abstract
Extensive venous malformations involving limbs severely impact quality of life, mostly due to chronic pain and functional limitations. But patients can also display coagulopathy with associated risks of life-threatening thromboembolism and bleeding. Available pharmacological treatments (e.g., sirolimus) are not universally effective. Novel therapies are urgently needed for patients with treatment-resistant venous malformations. We report three patients with TIE-2 receptor mutations treated with alpelisib for 6 months (daily dosing: 50 mg for children weighing <50 kg and 100 mg for those >50 kg). Pain was controlled, gait improved, size of the abnormal venous network decreased, and coagulopathy dramatically improved. Drug exposure was highly variable, suggesting that alpelisib dosing should be individualized to patient's characteristics and guided by therapeutic drug monitoring.
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Affiliation(s)
- Amandine Remy
- General Pediatric Fellowship Program, CHU Sainte-Justine, Université de Montréal, Montreal, Canada
| | - Thai Hoa Tran
- Division of Hematology-Oncology, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Canada
| | - Josée Dubois
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Department of Radiology, CHU Sainte-Justine, Université de Montréal, Montreal, Canada
| | - Paul Gavra
- Departement Clinique de Médecine de Laboratoire, Secteur Pharmacologie Clinique, Optilab Montréal - CHU Sainte-Justine, Montreal, Canada
| | - Chantal Lapointe
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - Rochelle Winikoff
- Division of Hematology-Oncology, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montreal, Canada
| | - Garcia-Bournissen Facundo
- Division of Paediatric Clinical Pharmacology, Department of Paediatrics, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Yves Théorêt
- Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Departement Clinique de Médecine de Laboratoire, Secteur Pharmacologie Clinique, Optilab Montréal - CHU Sainte-Justine, Montreal, Canada.,Department of Physiology and Pharmacology, CHU Sainte-Justine, Université de Montréal, Montreal, Canada
| | - Niina Kleiber
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Departement Clinique de Médecine de Laboratoire, Secteur Pharmacologie Clinique, Optilab Montréal - CHU Sainte-Justine, Montreal, Canada.,Department of Physiology and Pharmacology, CHU Sainte-Justine, Université de Montréal, Montreal, Canada.,Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montreal, Canada
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6
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Gourmel A, Rouette A, Benlimame N, El-Jalbout R, Dubé M, Théorêt Y, Piché N, Labonté S, Sinnett D, Cellot S, Dal-Soglio D, Larouche V, Tran TH. Durable Response to Trametinib in an Infant With ERC1-BRAF Infantile Fibrosarcoma-Like Tumor: A Case Report and Literature Review of BRAF-Altered Infantile Fibrosarcoma-Like Tumors. JCO Precis Oncol 2022; 6:e2200200. [PMID: 36103644 DOI: 10.1200/po.22.00200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Antoine Gourmel
- Division of Pediatric Hematology-Oncology, Charles-Bruneau Cancer Centre, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Université de Montreal, Montreal, QC, Canada
| | - Alexandre Rouette
- Molecular Diagnostics Laboratory, Charles-Bruneau Cancer Center, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Montréal, QC, Canada
| | - Naciba Benlimame
- Research Pathology Facility, Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada
| | - Ramy El-Jalbout
- Department of Radiology, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Montreal, QC, Canada
| | - Mireille Dubé
- Department of Medical Imaging, Centre Hospitalier Universitaire (CHU) de Québec, Québec, QC, Canada
| | - Yves Théorêt
- Clinical Pharmacology Laboratory, OPTILAB and Research Center, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Montréal, QC, Canada
| | - Nelson Piché
- Division of Paediatric Surgery, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Montréal, QC, Canada
| | - Sébastien Labonté
- Department of Pathology, Centre Hospitalier Universitaire (CHU) de Québec, Québec, QC, Canada
| | - Daniel Sinnett
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
| | - Sonia Cellot
- Division of Pediatric Hematology-Oncology, Charles-Bruneau Cancer Centre, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Université de Montreal, Montreal, QC, Canada.,Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
| | - Dorothée Dal-Soglio
- Department of Pathology and Clinical Laboratory Medicine, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Montréal, QC, Canada
| | - Valérie Larouche
- Department of Pediatrics, Centre Mère-Enfant Soleil du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
| | - Thai Hoa Tran
- Division of Pediatric Hematology-Oncology, Charles-Bruneau Cancer Centre, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Université de Montreal, Montreal, QC, Canada.,Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
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7
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Butler-Laporte G, Langevin MC, Lemieux C, Poirier C, Ferraro P, Théorêt Y, Luong ML. Voriconazole Therapeutic Drug Monitoring Among Lung Transplant Recipients Receiving Targeted Therapy for Invasive Aspergillosis. Clin Transplant 2022; 36:e14709. [PMID: 35575963 DOI: 10.1111/ctr.14709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/09/2022] [Accepted: 05/10/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Voriconazole is the first line treatment for invasive aspergillosis (IA) Current guidelines suggest performing regular voriconazole therapeutic drug monitoring (TDM) to optimize treatment efficacy. We aimed to determine if TDM was predictive of clinical outcome in LTRs. METHODS Retrospective chart review was performed for all LTRs with probable or proven IA, treated with voriconazole monotherapy and who underwent TDM during therapy. Clinical outcome and toxicity were measured at 12 weeks. Classification and regression tree (CART) analysis was used to determine the most predictive voriconazole level thresholds for successful outcome. RESULTS 118 TDM samples from 30 LTRs with IA were analyzed. Three LTRs were excluded due to early treatment discontinuation. The median TDM level was 1.2 μg/mL (range 0.06-7.3). At 12 weeks, 62% (17/27) of patients had a successful outcome, while 37% (10/27) of patients failed therapy. CART analysis determined that the best predictor for successful outcome was a median TDM level > 0.72 μg/mL. Seventy percent (14/20) of patients with median TDM above 0.72 μg/mL had a successful outcome, compared to 42.9% (3/7) of patients with a median TDM below 0.72 μg/mL (OR 3.11; 95% CI: 0.53-20.4; P = 0.21). CART analysis determined that a TDM level greater than 2.13 μg/mL was predictive of hepatotoxicity. CONCLUSIONS Our data suggests that a voriconazole TDM range between 0.72 μg/mL and 2.13 μg/mL may be associated with improved outcomes. Our study is in line with current recommendations on the use of voriconazole TDM in improving outcome and minimizing toxicity in LTR with IA. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Guillaume Butler-Laporte
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montréal, Canada
| | - Marie-Claude Langevin
- Department of Pharmacy, Centre Hospitalier de l'Université de Montréal, Montréal, Canada
| | - Claude Lemieux
- Department of Medical Microbiology, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Canada
| | - Charles Poirier
- Division of Respirology, Department of Medicine, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Canada
| | - Pasquale Ferraro
- Division of Thoracic Surgery, Department of Surgery, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Canada
| | - Yves Théorêt
- Department of Pharmacology, Centre de Recherche Pédiatrique, Hôpital Ste-Justine, Montréal, Canada
| | - Me-Linh Luong
- Department of Medical Microbiology, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Canada
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8
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Marcoux S, Théorêt Y, Dubois J, Essouri S, Pincivy A, Coulombe J, McCuaig C, Powell J, Soulez G, Kleiber N. Systemic, local, and sclerotherapy drugs: What do we know about drug prescribing in vascular anomalies? Pediatr Blood Cancer 2021; 68:e29364. [PMID: 34596969 DOI: 10.1002/pbc.29364] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 08/08/2021] [Accepted: 08/31/2021] [Indexed: 01/20/2023]
Abstract
Off-label drug prescribing, frequent in the treatment of vascular anomalies (VA), relies on the quality of the literature reporting drug efficacy and safety. Our objective is to review the level of evidence (LOE) surrounding drug use in VA, which is more prevalent in pediatric care. A list of drugs used in VA was created with a literature review in July 2020. For each drug listed, the article displaying the highest LOE was determined and then compared between efficacy/safety data, routes of administration, pharmacological categories and a subset of VA. The influence of research quality on study results was also explored. The median LOE for the 74 drugs identified poor methodological quality, with a predominance of retrospective studies or case reports. Drug safety is currently inadequately reported. This is alarming as many treatments display significant safety concerns. Also, current literature displays major publication bias that probably leads to overestimation of drug efficacy in VA.
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Affiliation(s)
- Simon Marcoux
- Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Clinical Pharmacology Unit, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Yves Théorêt
- Department of Pharmacology and Physiology, Université de Montréal, Montréal, Quebec, Canada.,Clinical Pharmacology Unit, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Josée Dubois
- Department of Radiology, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Sandrine Essouri
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Division of General Pediatrics, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Research Center, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Alix Pincivy
- Library, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Jérôme Coulombe
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Division of Dermatology, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Catherine McCuaig
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Division of Dermatology, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Julie Powell
- Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Division of Dermatology, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
| | - Gilles Soulez
- Department of Radiology, Centre Hospitalier de l'Université de Montréal (CHUM), Montréal, Quebec, Canada
| | - Niina Kleiber
- Department of Pharmacology and Physiology, Université de Montréal, Montréal, Quebec, Canada.,Clinical Pharmacology Unit, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Vascular Anomaly Team, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Division of General Pediatrics, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada.,Research Center, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada
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9
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Marcoux S, Théorêt Y, Dubois J, Essouri S, Pincicy A, Coulombe J, McCuaig C, Powell J, Soulez G, Kleiber N. 55 Evidence behind drug use in vascular anomalies: From infantile hemangioma to rare vascular anomalies … What do we know about what we do with local, systemic, or sclerotherapy treatment? Paediatr Child Health 2021. [DOI: 10.1093/pch/pxab061.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Primary Subject area
Clinical Pharmacology and Toxicology
Background
The most common vascular anomaly (VA) requiring medical treatment are infantile hemangiomas, but many other vascular anomalies affecting children are treated with local, systemic drugs or sclerosing agents.
Rational drug prescribing implies assessment of whether a drug’s benefits outweigh the risk of adverse effects for treatment of a specific vascular anomaly. This process relies on the quality of the literature on efficacy and safety for drug treatment of vascular anomalies.
Objectives
To evaluate the level of evidence surrounding drug use in vascular anomalies.
Design/Methods
A list of drugs used in vascular anomalies was created with existing guidelines. For each drug, the article displaying the highest level of evidence was determined, using Oxford criteria. Levels of evidence were compared between efficacy and safety data, routes of administration, pharmacological categories, and a subset of specific vascular anomalies. The influence of research quality on study results was explored by comparing the percentage of clinical efficacy between high- and low-quality studies.
Results
We identified 71 different drugs for treating vascular anomalies. The median level of evidence was low, with a predominance of retrospective cohort studies and case reports. The level of evidence was higher for efficacy than safety data and for common diseases like infantile hemangiomas. The level of evidence was lower for systemic vs. local drugs. Clinical efficacy was more frequently reported in low quality studies (retrospective cohort studies and case reports) than in high quality studies (randomized clinical trial and meta-analysis).
Conclusion
Quality of research on drugs used for treating vascular anomalies in infants is poor and challenges rational drug use. Indeed, knowledge of drug treatment in VA relies mainly on research of poor methodological quality. Despite the use of drugs carrying a significant risk of adverse effects, drug safety is also poorly reported. This is alarming because some treatments, like antineoplastic agents and immunosuppressants, display an unsafe adverse effect profile. A publication bias towards positive results probably leads to overestimation of drug efficacy in vascular anomalies. An independent international pharmacovigilance system for drug use in vascular anomalies is proposed to improve efficacy and safety reporting and promote quality drug prescribing.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Gilles Soulez
- Centre Hospitalier de l’Université de Montréal (CHUM)
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10
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Remy A, Théorêt Y, Ansari M, Bittencourt H, Ducruet T, Nava T, Pastore Y, Rezgui MA, Krajinovic M, Kleiber N. Is Busulfan Clearance Different in Patients With Sickle Cell Disease? Let's Clear Up That Case With Some Controls. J Pediatr Hematol Oncol 2021; 43:e867-e872. [PMID: 33661168 DOI: 10.1097/mph.0000000000002106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 12/28/2020] [Indexed: 11/26/2022]
Abstract
In busulfan-based conditioning regimen for hematopoietic stem cell transplantation in children, accurate a priori determination of the first dose is important because of its narrow therapeutic window. Sickle cell disease (SCD) influences pharmacokinetics of the commonly used drugs by affecting organs responsible for drug metabolism and elimination. This pharmacokinetics study assesses the influence of SCD on the metabolic pathway of busulfan that is mainly metabolized in the liver. In this retrospective cross-sectional case-control study, 16 patients with SCD were matched to 50 patients without SCD on known busulfan clearance's covariates (glutathione-S-transferase alpha1 polymorphisms, age, weight). Clearance of the first dose of busulfan was not significantly different independently of genetic or anthropometric factors in patients with or without SCD.
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Affiliation(s)
- Amandine Remy
- Department of Pediatric Hematology, Univ. Lille, CHU Lille, Lille, France
- Unité de pharmacologie clinique
| | - Yves Théorêt
- Unité de pharmacologie clinique
- Departments of Pharmacology and Physiology
- Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, Université de Montréal
| | - Marc Ansari
- CANSEARCH Research Laboratory, Department of Pediatrics, Gynecology and Obstetrics, University of Geneva
- Department of Women-Children-Adolescents, Division of General Pediatrics, Pediatric Onco-Hematology Unit, Geneva University Hospital, Geneva, Switzerland
| | - Henrique Bittencourt
- Pediatrics
- Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, Université de Montréal
| | - Thierry Ducruet
- Applied Clinical Research Unit, CHU Sainte-Justine, Montreal, QC, Canada
| | - Tiago Nava
- CANSEARCH Research Laboratory, Department of Pediatrics, Gynecology and Obstetrics, University of Geneva
- Department of Women-Children-Adolescents, Division of General Pediatrics, Pediatric Onco-Hematology Unit, Geneva University Hospital, Geneva, Switzerland
| | - Yves Pastore
- Pediatrics
- Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, Université de Montréal
| | - Mohamed A Rezgui
- Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, Université de Montréal
| | - Maja Krajinovic
- Departments of Pharmacology and Physiology
- Pediatrics
- Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, Université de Montréal
| | - Niina Kleiber
- Departments of Pharmacology and Physiology
- Pediatrics
- Research Center, CHU Sainte-Justine
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11
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Franck B, Woillard JB, Théorêt Y, Bittencourt H, Demers E, Briand A, Marquet P, Lapeyraque AL, Ovetchkine P, Autmizguine J. Population pharmacokinetics of ganciclovir and valganciclovir in paediatric solid organ and stem cell transplant recipients. Br J Clin Pharmacol 2021; 87:3105-3114. [PMID: 33373493 DOI: 10.1111/bcp.14719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 11/26/2020] [Accepted: 12/11/2020] [Indexed: 11/27/2022] Open
Abstract
AIMS Ganciclovir (GCV) and its prodrug valganciclovir (VGCV) are first-line agents to prevent and treat cytomegalovirus in transplant recipients. There is high pharmacokinetic (PK) interindividual variability and PK data are scarce, especially in paediatric stem cell transplant (SCT) recipients. We sought to determine the optimal GCV and VGCV dosing in transplanted children. METHODS We conducted a single-centre retrospective population PK (POPPK) study of IV GCV and enteral VGCV in paediatric solid organ transplant (SOT) and SCT recipients. We included children who were transplanted and had available plasma GCV concentrations, done per standard of care. POPPK analysis was performed using a nonlinear mixed effects modelling approach with NONMEM. Optimal dosing was determined based on the achievement of the surrogate efficacy target: GCV 24 h area under the concentration-time curve (AUC0-24h ) of 40-60 mg.h.L-1 . RESULTS Fifty children with a median [range] age of 7.5 years [0.5-17.4] contributed 580 PK samples. A two-compartment model with first-order absorption with a lag time and first-order elimination fit the data well. Creatinine clearance and body weight (WT) were significant covariates for GCV clearance (CL); and WT for the volumes of distribution. IV GCV 15-20 mg.kg-1 .day-1 divided every 12 hours achieved the highest probability of target achievement (PTA) (33.0-33.8%). Enteral VGCV 30 and 40 mg.kg-1 .day-1 divided every 12 hours in children 0-<6 years, and 6-18 years, respectively, achieved the highest PTA (29.1-33.0%). CONCLUSION This is the first POPPK model developed in children with either SOT or SCT. Concentration target achievement was low, suggesting a potential benefit for therapeutic drug monitoring to ensure optimal exposure.
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Affiliation(s)
- Bénédicte Franck
- INSERM, IPPRITT, U1248, Limoges, France.,Univ. Limoges, IPPRITT, Limoges, France.,Department of Pharmacology and Toxicology, CHU Limoges, Limoges, France
| | - Jean-Baptiste Woillard
- INSERM, IPPRITT, U1248, Limoges, France.,Univ. Limoges, IPPRITT, Limoges, France.,Department of Pharmacology and Toxicology, CHU Limoges, Limoges, France
| | - Yves Théorêt
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montreal, Quebec, Canada
| | | | - Emile Demers
- Department of Pharmacy, CHU Sainte-Justine, Montreal, Quebec, Canada
| | - Annabelle Briand
- Research Center, CHU Sainte-Justine, Quebec, Montreal, Canada.,Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
| | - Pierre Marquet
- INSERM, IPPRITT, U1248, Limoges, France.,Univ. Limoges, IPPRITT, Limoges, France.,Department of Pharmacology and Toxicology, CHU Limoges, Limoges, France
| | | | | | - Julie Autmizguine
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montreal, Quebec, Canada.,Department of Pediatrics, CHU Sainte-Justine, Montreal, Quebec, Canada.,Research Center, CHU Sainte-Justine, Quebec, Montreal, Canada.,Department of Pharmacology and Physiology, Université de Montréal, Montreal, Quebec, Canada
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12
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Litalien C, Autmizguine J, Carli A, Giroux D, Lebel D, Leclerc JM, Théorêt Y, Gilpin A, Bérubé S. Providing Suitable Pediatric Formulations for Canadian Children: A Call for Action. Can J Hosp Pharm 2020. [DOI: 10.4212/cjhp.v73i4.3023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Background: Many medications given to children have no commercially available, age-appropriate formulations. This leads to manipulation of dosage forms designed for adults (compounding), which can result in an increased risk of dosing errors and adverse events, lack of medication adherence because of taste issues, and suboptimal dosing with therapeutic failure.Objectives: To determine which drugs required compounding for oral administration to children in a Canadian hospital and, for each compounded drug, to determine whether it was available as licensed oral pediatric formulations in the United States or the European Union.Methods: Drugs requiring compounded liquid formulations for oral administration, dispensed from January 1 to December 31, 2015, at a Canadian university-affiliated tertiary pediatric hospital, and prepared in a quantity exceeding 0.5 L per year, were retrospectively identified. The online drug databases of Health Canada, the US Food and Drug Administration, the European Medicines Agency (EMA), and the UK Medicines and Healthcare Products Regulatory Agency were searched to determine the availability of child-friendly oral formulations for these drugs. The regulatory status in each jurisdiction was also compared. For licensed formulations with potential concerns about excipient safety, EMA guidelines for sorbitol, propylene glycol, ethanol, and sodium benzoate were used to determine pediatric suitability.Results: Of the 56 compounded drugs investigated, 27 (48%) had a suitable commercialized child-friendly formulation available outside Canada. Overall, these drugs had been on the Canadian market for a median of 35 years, and almost half (27 [48%]) had a pediatric indication in Canada.Conclusions: Canada is lagging behind the United States and the European Union in ensuring availability of and access to suitable pediatric formulations. Potential explanations for this gap include small market size, regulatory uncertainties, and reimbursement shortcomings. Steps must be taken to implement pediatric-sensitive regulations and incentives, as well as reimbursement policies, to address these unmet needs.Keywords: compounding, child-friendly medicines, pediatric oral medicinesRÉSUMÉContexte : Plusieurs médicaments administrés aux enfants ne sont pas disponibles commercialement sous une forme pharmaceutique adaptée à leur âge. Ceci entraîne une manipulation des formes destinées aux adultes (préparation magistrale) et peut conduire à une augmentation du risque d’erreurs de dosage et d’effets indésirables, un manque d’observance médicamenteuse secondairement à des problèmes de goût, et un dosage sous-optimal associé à des échecs thérapeutiques.Objectifs : Définir les médicaments qui exigent une préparation magistrale pour être administrés par voie orale aux enfants dans un hôpital canadien et, pour chaque médicament faisant l’objet d’une préparation magistrale, déterminer s’il est disponible sous une forme pharmaceutique orale autorisée pour les enfants aux États-Unis ou dans l’Union européene.Méthodes : Les médicaments nécessitant des préparations magistrales liquides pour administration orale, distribués entre le 1er janvier et le 31 décembre 2015 dans un hôpital de soins pédiatriques tertiaires affilié à une université canadienne et dont la quantité préparée était supérieure à 0.5 L par an, ont été déterminés rétrospectivement. Les bases de données en ligne de médicaments de Santé Canada, de la Food and Drug Administration américaine, de l’Agence européenne des médicaments (AEM) et de la Medicines and Healthcare Products Regulatory Agency (Royaume-Uni) ont été interrogées pour déterminer la disponibilité de formes pharmaceutiques orales adaptées aux enfants pour ces médicaments. Le statut réglementaire de chaque pays a également fait l’objet d’une comparaison. Pour les formes pharmaceutiques autorisées présentant des problèmes potentiels d’innocuité des excipients, les directives de l’AEM concernant le sorbitol, le propylène glycol, l’éthanol et le benzoate de sodium ont servi à déterminer si un usage pédiatrique était acceptable.Résultats : Des 56 médicaments étudiés faisant l’objet d’une préparation magistrale, 27 (48 %) avaient une forme pharmaceutique commercialisée adaptée aux enfants en dehors du Canada. Au total, ces médicaments sont sur le marché canadien depuis une médiane de 35 ans et près de la moitié (27 [48 %]) ont une indication pédiatrique au Canada.Conclusions : Le Canada accuse un retard par rapport aux États-Unis et à l’Union européenne quant à la disponibilité et à l’accès à des formes pharmaceutiques adéquates pour les enfants. La petite taille du marché, les incertitudes en matière réglementaire et les lacunes concernant le remboursement pourraient notamment expliquer cet écart. Il est nécessaire de prendre des mesures pour mettre en place des réglementations et des incitatifs ainsi que des politiques de remboursement axés sur les enfants pour répondre à ces besoins criants.Mots-clés : préparation magistrale, médicaments adaptés aux enfants, médicaments pédiatriques pour administration orale
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13
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Litalien C, Autmizguine J, Carli A, Giroux D, Lebel D, Leclerc JM, Théorêt Y, Gilpin A, Bérubé S. Providing Suitable Pediatric Formulations for Canadian Children: A Call for Action. Can J Hosp Pharm 2020; 73:247-256. [PMID: 33100356 PMCID: PMC7556390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
BACKGROUND Many medications given to children have no commercially available, age-appropriate formulations. This leads to manipulation of dosage forms designed for adults (compounding), which can result in an increased risk of dosing errors and adverse events, lack of medication adherence because of taste issues, and suboptimal dosing with therapeutic failure. OBJECTIVES To determine which drugs required compounding for oral administration to children in a Canadian hospital and, for each compounded drug, to determine whether it was available as licensed oral pediatric formulations in the United States or the European Union. METHODS Drugs requiring compounded liquid formulations for oral administration, dispensed from January 1 to December 31, 2015, at a Canadian university-affiliated tertiary pediatric hospital, and prepared in a quantity exceeding 0.5 L per year, were retrospectively identified. The online drug databases of Health Canada, the US Food and Drug Administration, the European Medicines Agency (EMA), and the UK Medicines and Healthcare Products Regulatory Agency were searched to determine the availability of child-friendly oral formulations for these drugs. The regulatory status in each jurisdiction was also compared. For licensed formulations with potential concerns about excipient safety, EMA guidelines for sorbitol, propylene glycol, ethanol, and sodium benzoate were used to determine pediatric suitability. RESULTS Of the 56 compounded drugs investigated, 27 (48%) had a suitable commercialized child-friendly formulation available outside Canada. Overall, these drugs had been on the Canadian market for a median of 35 years, and almost half (27 [48%]) had a pediatric indication in Canada. CONCLUSIONS Canada is lagging behind the United States and the European Union in ensuring availability of and access to suitable pediatric formulations. Potential explanations for this gap include small market size, regulatory uncertainties, and reimbursement shortcomings. Steps must be taken to implement pediatric-sensitive regulations and incentives, as well as reimbursement policies, to address these unmet needs.
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Affiliation(s)
- Catherine Litalien
- , MD, FRCPC, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre, the Department of Medical Biology, and the Research Centre of the CHU Sainte-Justine, Montréal, Quebec. She is also with the Department of Pediatrics and the Department of Pharmacology and Physiology, Université de Montréal, Montréal, Quebec
| | - Julie Autmizguine
- , MD, FRCPC, MSc, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre, the Department of Medical Biology, and the Research Centre of the CHU Sainte-Justine, Montréal, Quebec. She is also with the Department of Pediatrics and the Department of Pharmacology and Physiology, Université de Montréal, Montréal, Quebec
| | - Antoine Carli
- , BPharm, MSc, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre of the CHU Sainte-Justine, Montréal, Quebec
| | - Denis Giroux
- , BPharm, MSc, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre of the CHU Sainte-Justine, Montréal, Quebec
| | - Denis Lebel
- , BPharm, MSc, FCSHP, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre and the Department of Pharmacy, CHU Sainte-Justine, Montréal, Quebec
| | - Jean-Marie Leclerc
- , MD, FRCPC, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre and the Department of Medical Biology of the CHU Sainte-Justine, Montréal, Quebec. He is also with the Department of Pediatrics, Université de Montréal, Montréal, Quebec
| | - Yves Théorêt
- ê, BPharm, PhD, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre, the Department of Medical Biology, and the Research Centre of the CHU Sainte-Justine, Montréal, Quebec. He is also with the Department of Pharmacology and Physiology, Université de Montréal, Montréal, Quebec
| | - Andrea Gilpin
- , PhD, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre of the CHU Sainte-Justine, Montréal, Quebec
| | - Sophie Bérubé
- , BPharm, MSc, is with the Rosalind & Morris Goodman Family Pediatric Formulations Centre of the CHU Sainte-Justine, Montréal, Quebec
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14
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Merlen C, Bonnefoy A, Afeich C, Théorêt Y, Laverdière C, Leclerc JM, Rivard GE. Antithrombin and fibrinogen levels as predictors for plasma L-asparaginase activity in children with acute lymphoblastic leukemia. Pediatr Blood Cancer 2019; 66:e27729. [PMID: 30938058 DOI: 10.1002/pbc.27729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/08/2019] [Accepted: 02/27/2019] [Indexed: 11/11/2022]
Abstract
BACKGROUND L-asparaginase is a cornerstone treatment for children with acute lymphoblastic leukemia (ALL). However, immune reaction to the drug may increase the clearance or impair the function of L-asparaginase and reduces its therapeutic efficacy. The objective of this study was to identify potential plasma proteins that could be used as proxies for L-asparaginase activity. METHODS Fibrinogen, von Willebrand factor antigen (VWF:Ag), total protein, and albumin levels as well as antithrombin (AT) and L-asparaginase activities were measured in 97 children with ALL treated for prolonged period of time with L-asparaginase. Binary logistic regression and a receiver operating characteristic (ROC) curve analysis were performed to evaluate the predictive value of plasma proteins for L-asparaginase activity. RESULTS Median E. coli L-asparaginase activity was 220 IU/L (range, 0-1308) throughout the treatment period. L-asparaginase activity was below 100 IU/L in 23% of measured samples. L-asparaginase activity was inversely associated with AT activity, fibrinogen, total protein, and albumin levels (r = -0.63, -0.62, -0.57, and -0.45, respectively; P < 0.0001), but not with VWF:Ag. ROC curve analyses showed an intermediate accuracy of AT activity (area under the ROC curve [AUC] = 0.77) to detect specimens with subtherapeutic level of L-asparaginase. An optimal accuracy was found when AT and fibrinogen were combined (AUC = 0.82; sensitivity = 75%; specificity = 82%; positive predictive value = 55%; negative predictive value = 92%) with cutoff values of 0.73 IU/mL and 1.85 g/L, respectively. CONCLUSIONS AT combined with fibrinogen levels could be used as a proxy to identify patients with therapeutic level of L-asparaginase activity in the absence of real-time asparaginase measurement during prolonged exposure to L-asparaginase.
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Affiliation(s)
- Clémence Merlen
- Department of Hematology/Oncology, CHU Sainte-Justine, Montreal, QC, Canada
| | - Arnaud Bonnefoy
- Department of Hematology/Oncology, CHU Sainte-Justine, Montreal, QC, Canada
| | - Cynthia Afeich
- Department of Pharmacology, CHU Sainte-Justine, Montreal, QC, Canada
| | - Yves Théorêt
- Department of Pharmacology, CHU Sainte-Justine, Montreal, QC, Canada
| | | | - Jean-Marie Leclerc
- Department of Hematology/Oncology, CHU Sainte-Justine, Montreal, QC, Canada
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15
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Le Sage S, David M, Dubois J, Powell J, McCuaig CC, Théorêt Y, Kleiber N. Efficacy and absorption of topical sirolimus for the treatment of vascular anomalies in children: A case series. Pediatr Dermatol 2018; 35:472-477. [PMID: 29790593 DOI: 10.1111/pde.13547] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND/OBJECTIVES Efficacy of topical sirolimus has recently been described in lymphatic anomalies but not in other types of vascular anomalies. To our knowledge, systemic absorption of topical sirolimus in these lesions has not yet been reported. The objective was to evaluate the efficacy, tolerance, and absorption of topical sirolimus 0.1% with different types of vascular anomalies in children. METHODS Sirolimus 0.1% was applied on cutaneous vascular anomalies in six children aged 2-17. These anomalies consisted of three extratruncular micro- and macrocystic lymphatic malformations and one each verrucous venous malformation, truncular lymphatic malformation with angiokeratomas, and infantile hemangioma. Sirolimus blood levels were measured after 1 week, 1 month, and 3 months. RESULTS A rapid decrease in the size of superficial lymphatic malformations in three of six patients and a significant decrease in discharge from oozing lesions were observed. Response occurred in less than 3 months. The truncular lymphatic malformation, verrucous venous malformation, and infantile hemangioma did not respond to topical sirolimus. Sirolimus levels were undetectable. Adverse effects were limited to local irritation. CONCLUSIONS Topical sirolimus 0.1% is a useful treatment for cutaneous manifestations of extratruncular lymphatic malformations. The only adverse effect is local irritation. No systemic effects are expected, because blood levels are clinically insignificant.
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Affiliation(s)
- Sophie Le Sage
- Faculty of Medicine, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Michèle David
- Division of Hematology-Oncology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Josée Dubois
- Department of Radiology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Julie Powell
- Division of Dermatology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Catherine C McCuaig
- Division of Dermatology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Yves Théorêt
- Department of Pharmacology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada.,Clinical Pharmacology Unit, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Niina Kleiber
- Department of General Pediatrics, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada.,Clinical Pharmacology Unit, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
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16
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McMahon J, Théorêt Y, Autmizguine J, Bittencourt H, Tapiéro B, Ovetchkine P. Posaconazole Plasma Monitoring in Immunocompromised Children. J Pediatric Infect Dis Soc 2017; 6:389-392. [PMID: 28186550 DOI: 10.1093/jpids/piw087] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 12/06/2016] [Indexed: 11/12/2022]
Abstract
Plasma posaconazole exposure was assessed in 13 children who underwent a hematopoietic stem cell transplant. The median dosage was 12.5 mg/kg per day, divided into 3 doses. Of these 13 patients, 46.2% (6) and 30.8% (4) achieved concentrations higher than 0.7 and 1.25 mg/L, respectively. In children at high risk, a higher dosage might be needed to achieve target concentrations.
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Affiliation(s)
| | - Yves Théorêt
- Research Centre.,Infectious Diseases Division, Department of Pediatrics.,Hemato-Oncology Division, Department of Pediatrics, CHU Sainte-Justine-Université de Montréal, Québec, Canada
| | - Julie Autmizguine
- Research Centre.,Infectious Diseases Division, Department of Pediatrics.,Hemato-Oncology Division, Department of Pediatrics, CHU Sainte-Justine-Université de Montréal, Québec, Canada.,Clinical Pharmacology Unit, CHU Sainte-Justine, Montréal, Québec, Canada
| | | | - Bruce Tapiéro
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montréal, Québec, Canada
| | - Philippe Ovetchkine
- Research Centre.,Clinical Pharmacology Unit, CHU Sainte-Justine, Montréal, Québec, Canada
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17
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Thibault C, Kassir N, Théorêt Y, Varin F, Litalien C, Autmizguine J. Dose-Exposure Simulation for Piperacillin-Tazobactam Dosing Strategies in Infants and Young Children. J Popul Ther Clin Pharmacol 2017; 24:e33-344. [PMID: 28873292 DOI: 10.22374/1710-6222.24.1.3.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Indexed: 11/24/2022]
Abstract
BACKGROUND Extended piperacillin-tazobactam (TZP) infusions have been associated with favourable outcomes. There are currently no pediatric dosing recommendations. OBJECTIVES To determine appropriate TZP dosing strategies in children 2 months - 6 years according to age and different minimal inhibitory concentrations (MICs). METHODS Age and weight were simulated for 1000 children. Post-hoc pharmacokinetic parameter estimates were generated using published clearance and volume of distribution data. For different dosing regimens, we estimated the probability of target attainment (PTA) over a range of MICs from 4 to 128 mg/L. The pharmacodynamic (PD) target was defined as free piperacillin concentrations above the MIC for ≥ 50% of the dosing interval. A PTA ≥ 90% was defined as optimal. RESULTS PTA decreased as MIC and age increased. In all age groups, standard dosing regimens (240-300 mg/kg/day, 0.5h infusions) failed to reach PTAs ≥ 90% at MICs ≥ 16 mg/L. Standard 0.5h infusions reached PTAs ≥ 90% at MICs up to 8 mg/L in infants > 2 to 6m. No 0.5h infusion reached PTAs ≥ 90% for MICs ≥ 4 mg/L in children > 6m. While none of the tested regimens were optimal at MICs > 16 mg/L in children > 6m, 100 mg/kg/dose every 6h as a 3h infusion reached PD target at MICs of 32 mg/L in infants > 2 to 6m. CONCLUSIONS Up to MICs of 16 mg/L, 90 mg/kg/dose every 8h as a 2h infusion in infants > 2 to 6m and 100 mg/kg/dose every 8h as a 4h infusion in children > 6m-6y achieved PTAs ≥ 90%.
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Affiliation(s)
- Céline Thibault
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montreal, QC, Canada.,Department of Pediatrics, CHU Sainte-Justine, Montreal, QC, Canada
| | | | - Yves Théorêt
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montreal, QC, Canada.,Department of Pediatrics, CHU Sainte-Justine, Montreal, QC, Canada.,Certara Strategic Consulting, Montreal, QC, Canada.,Department of Pharmacology and Physiology, University of Montreal, Montreal, QC, Canada
| | - France Varin
- Faculty of Pharmacy, University of Montreal, Montreal, QC, Canada
| | - Catherine Litalien
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montreal, QC, Canada.,Department of Pediatrics, CHU Sainte-Justine, Montreal, QC, Canada.,Certara Strategic Consulting, Montreal, QC, Canada.,Department of Pharmacology and Physiology, University of Montreal, Montreal, QC, Canada
| | - Julie Autmizguine
- Clinical Pharmacology Unit, CHU Sainte-Justine, Montreal, QC, Canada.,Department of Pediatrics, CHU Sainte-Justine, Montreal, QC, Canada.,Certara Strategic Consulting, Montreal, QC, Canada.,Department of Pharmacology and Physiology, University of Montreal, Montreal, QC, Canada
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18
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Uppugunduri CRS, Storelli F, Mlakar V, Huezo-Diaz Curtis P, Rezgui A, Théorêt Y, Marino D, Doffey-Lazeyras F, Chalandon Y, Bader P, Daali Y, Bittencourt H, Krajinovic M, Ansari M. The Association of Combined GSTM1 and CYP2C9 Genotype Status with the Occurrence of Hemorrhagic Cystitis in Pediatric Patients Receiving Myeloablative Conditioning Regimen Prior to Allogeneic Hematopoietic Stem Cell Transplantation. Front Pharmacol 2017; 8:451. [PMID: 28744217 PMCID: PMC5504863 DOI: 10.3389/fphar.2017.00451] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 06/22/2017] [Indexed: 12/01/2022] Open
Abstract
Hemorrhagic cystitis (HC) is one of the complications of busulfan-cyclophosphamide (BU-CY) conditioning regimen during allogeneic hematopoietic stem cell transplantation (HSCT) in children. Identifying children at high risk of developing HC in a HSCT setting could facilitate the evaluation and implementation of effective prophylactic measures. In this retrospective analysis genotyping of selected candidate gene variants was performed in 72 children and plasma Sulfolane (Su, water soluble metabolite of BU) levels were measured in 39 children following treatment with BU-CY regimen. The cytotoxic effects of Su and acrolein (Ac, water soluble metabolite of CY) were tested on human urothelial cells (HUCs). The effect of Su was also tested on cytochrome P 450 (CYP) function in HepaRG hepatic cells. Cumulative incidences of HC before day 30 post HSCT were estimated using Kaplan–Meier curves and log-rank test was used to compare the difference between groups in a univariate analysis. Multivariate Cox regression was used to estimate hazard ratios with 95% confidence intervals (CIs). Multivariate analysis included co-variables that were significantly associated with HC in a univariate analysis. Cumulative incidence of HC was 15.3%. In the univariate analysis, HC incidence was significantly (p < 0.05) higher in children older than 10 years (28.6 vs. 6.8%) or in children with higher Su levels (>40 vs. <11%) or in carriers of both functional GSTM1 and CYP2C9 (33.3 vs. 6.3%) compared to the other group. In a multivariate analysis, combined GSTM1 and CYP2C9 genotype status was associated with HC occurrence with a hazards ratio of 4.8 (95% CI: 1.3–18.4; p = 0.02). Ac was found to be toxic to HUC cells at lower concentrations (33 μM), Su was not toxic to HUC cells at concentrations below 1 mM and did not affect CYP function in HepaRG cells. Our observations suggest that pre-emptive genotyping of CYP2C9 and GSTM1 may aid in selection of more effective prophylaxis to reduce HC development in pediatric patients undergoing allogeneic HSCT. Article summary: (1) Children carrying functional alleles in GSTM1 and CYP2C9 are at high risk for developing hemorrhagic cystitis following treatment with busulfan and cyclophosphamide based conditioning regimen. (2) Identification of children at high risk for developing hemorrhagic cystitis in an allogeneic HSCT setting will enable us to evaluate and implement optimal strategies for its prevention. Trial registration: This study is a part of the trail “clinicaltrials.gov identifier: NCT01257854.”
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Affiliation(s)
- Chakradhara Rao S Uppugunduri
- Onco-Hematology Unit, Geneva University Hospital, Department of PediatricsGeneva, Switzerland.,CANSEARCH Research Laboratory, Department of Pediatrics, Faculty of Medicine, University of GenevaGeneva, Switzerland
| | - Flavia Storelli
- Clinical Pharmacology and Toxicology Service, Geneva University HospitalGeneva, Switzerland
| | - Vid Mlakar
- Onco-Hematology Unit, Geneva University Hospital, Department of PediatricsGeneva, Switzerland.,CANSEARCH Research Laboratory, Department of Pediatrics, Faculty of Medicine, University of GenevaGeneva, Switzerland
| | - Patricia Huezo-Diaz Curtis
- Onco-Hematology Unit, Geneva University Hospital, Department of PediatricsGeneva, Switzerland.,CANSEARCH Research Laboratory, Department of Pediatrics, Faculty of Medicine, University of GenevaGeneva, Switzerland
| | - Aziz Rezgui
- CHU Sainte-Justine Research Center, Charles-Bruneau Cancer Center, MontrealQC, Canada
| | - Yves Théorêt
- Clinical Pharmacology Unit, CHU Sainte-Justine, MontrealQC, Canada
| | - Denis Marino
- CANSEARCH Research Laboratory, Department of Pediatrics, Faculty of Medicine, University of GenevaGeneva, Switzerland
| | | | - Yves Chalandon
- Division of Hematology, Department of Medical Specialties, Geneva University HospitalGeneva, Switzerland
| | - Peter Bader
- Division for Stem Cell Transplantation and Immunology, University Hospital FrankfurtFrankfurt, Germany
| | - Youssef Daali
- Clinical Pharmacology and Toxicology Service, Geneva University HospitalGeneva, Switzerland
| | - Henrique Bittencourt
- Department of Pediatrics, Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, MontrealQC, Canada
| | - Maja Krajinovic
- CHU Sainte-Justine Research Center, Charles-Bruneau Cancer Center, MontrealQC, Canada.,Clinical Pharmacology Unit, CHU Sainte-Justine, MontrealQC, Canada.,Department of Pediatrics, Charles-Bruneau Cancer Center, CHU Sainte-Justine Research Center, MontrealQC, Canada
| | - Marc Ansari
- Onco-Hematology Unit, Geneva University Hospital, Department of PediatricsGeneva, Switzerland.,CANSEARCH Research Laboratory, Department of Pediatrics, Faculty of Medicine, University of GenevaGeneva, Switzerland
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Jensen ME, Ducharme FM, Théorêt Y, Bélanger AS, Delvin E. Data in support for the measurement of serum 25-hydroxyvitamin D (25OHD) by tandem mass spectrometry. Data Brief 2016; 8:925-9. [PMID: 27508244 PMCID: PMC4961221 DOI: 10.1016/j.dib.2016.07.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/09/2016] [Accepted: 07/08/2016] [Indexed: 11/29/2022] Open
Abstract
This article provides data and a method related to a research paper entitled “Assessing vitamin D nutritional status: is capillary blood adequate?” (Jensen et al., 2016) [1]. Circulating 25OHD, the accepted biomarker of the vitamin D nutritional status, is routinely measured by automated immunoassays, that although may be performed in hospital central laboratories, often suffer from a lack of specificity with regards to the different vitamin D metabolites, “Measurement of circulating 25-hydroxyvitamin D: a historical review” (Le Goff et al., 2015) [2]. Mass spectrometry offers this specificity. This article describes the performance of an in-house tandem mass spectrometry method for the individual measurement of 25OHD3, 25OHD2 and 3-épi-25OHD3.
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Affiliation(s)
- M E Jensen
- Centre for Asthma and Respiratory Diseases, School of Biomedical Sciences & School of Medicine and Public Health, University of Newcastle, Callaghan, Australia
| | - F M Ducharme
- Departments of Pediatrics and Social and Preventive Medicine, University of Montreal, Montreal, Canada; Clinical Research and Knowledge Transfer Unit, Research Centre, CHU Ste-Justine, Montreal, Canada
| | - Y Théorêt
- Clinical Pharmacology Unit, Department of Clinical Biochemistry, CHU Ste-Justine, Canada; Department of Pharmacology, University of Montreal, Montreal, Canada
| | - A-S Bélanger
- Department of Clinical Biochemistry, CHU Ste-Justine, Canada
| | - E Delvin
- Gatroenterology, Hepatology & Nutrition Division, CHU Ste-Justine Research Centre, University of Montreal, Montreal, Canada
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20
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Robaey P, Dobkin P, Leclerc JM, Cyr F, Sauerwein C, Théorêt Y. A comprehensive model of the development of mental handicap in children treated for acute lymphoblastic leukaemia: A synthesis of the literature. International Journal of Behavioral Development 2016. [DOI: 10.1080/016502500383467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Most clinical studies addressing sequelae in children with leukaemia are not theory-driven. Nonetheless, the role of different mediating biological (e.g. cranial irradiation, chemotherapy) and psychosocial variables (e.g. family functioning) has been empirically acknowledged. In these studies, a cause-effect relationship between biological variables and cognitive deficits, sometimes complex due to multiple agents, has been hypothesised. As for the psychosocial consequences, adaptation to the cancer-related stress has been the main focus, at both the individual and family levels. In this paper, we advocate the use of a global model for the development of handicap, derived from the International Classification of Impairments, Disabilities and Handicaps (ICIDH) by the World Health Organisation. This revised model proposes that handicap is the result of complex interactions between the characteristics of a person’s impairment, disabilities, and the characteristics of the environment. At each of these levels, risk/resilience factors are defined. This means that depending on the environmental obstacles they face, persons with an impairment or a disability may or may not experience a situation creating a handicap which is no longer seen as a stable status resulting from a disease to which the individual must adapt. By reviewing animal and clinical studies, current knowledge pertaining to leukaemia sequelae are integrated into the different levels defined by the model: organic impairment, disabilities, environmental obstacles, and handicap situation. Practical implications for research, policies, and individual treatments, and comparisons with existing models, are also outlined.
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Affiliation(s)
- Philippe Robaey
- Centre de Recherche de l’Hôpital Sainte-Justine,
Montréal, Québec, Canada
| | - Patricia Dobkin
- Montreal General Hospital and McGill University, Montréal,
Québec, Canada
| | | | | | | | - Yves Théorêt
- Centre de Recherche de l’Hôpital Sainte-Justine,
Montréal, Québec, Canada
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Jensen ME, Ducharme FM, Théorêt Y, Bélanger AS, Delvin E. Assessing vitamin D nutritional status: Is capillary blood adequate? Clin Chim Acta 2016; 457:59-62. [PMID: 27018135 DOI: 10.1016/j.cca.2016.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 02/21/2016] [Accepted: 03/22/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND Venous blood is the usual sample for measuring various biomarkers, including 25-hydroxyvitamin D (25OHD). However, it can prove challenging in infants and young children. Hence the finger-prick capillary collection is an alternative, being a relatively simple procedure perceived to be less invasive. We elected to validate the use of capillary blood sampling for 25OHD quantification by liquid chromatography tandem-mass spectrometry (LC/MS-MS). METHODS Venous and capillary blood samples were simultaneously collected from 15 preschool-aged children with asthma 10days after receiving 100,000IU of vitamin-D3 or placebo and 20 apparently healthy adult volunteers. 25OHD was measured by an in-house LC/MS-MS method. RESULTS The venous 25OHD values varied between 23 and 255nmol/l. The venous and capillary blood total 25OHD concentrations highly correlated (r(2)=0.9963). The mean difference (bias) of capillary blood 25OHD compared to venous blood was 2.0 (95% CI: -7.5, 11.5) nmol/l. CONCLUSION Our study demonstrates excellent agreement with no evidence of a clinically important bias between venous and capillary serum 25OHD concentrations measured by LC/MS-MS over a wide range of values. Under those conditions, capillary blood is therefore adequate for the measurement of 25OHD.
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Affiliation(s)
- M E Jensen
- Centre for Asthma and Respiratory Diseases, School of Biomedical Sciences, School of Medicine and Public Health, University of Newcastle, Callaghan, Australia
| | - F M Ducharme
- Departments of Pediatrics and Social and Preventive Medicine, University of Montreal, Canada; Clinical Research and Knowledge Transfer Unit, Research Centre, CHU Ste-Justine, Montreal, Canada
| | - Y Théorêt
- Clinical Pharmacology Unit, Department of Clinical Biochemistry, CHU Ste-Justine, Canada; Department of Pharmacology, University of Montreal, Canada
| | - A-S Bélanger
- Department of Clinical Biochemistry, CHU Ste-Justine, Canada
| | - E Delvin
- Gatroenterology, Hepatology & Nutrition Division, CHU Ste-Justine Research Centre, University of Montreal, Canada.
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22
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Kassir N, Labbé L, Delaloye JR, Mouksassi MS, Lapeyraque AL, Alvarez F, Lallier M, Beaunoyer M, Théorêt Y, Litalien C. Population pharmacokinetics and Bayesian estimation of tacrolimus exposure in paediatric liver transplant recipients. Br J Clin Pharmacol 2015; 77:1051-63. [PMID: 24977292 DOI: 10.1111/bcp.12276] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
AIMS The objectives of this study were to develop a population pharmacokinetic (PopPK) model for tacrolimus in paediatric liver transplant patients and determine optimal sampling strategies to estimate tacrolimus exposure accurately. METHODS Twelve hour intensive pharmacokinetic profiles from 30 patients (age 0.4-18.4 years) receiving tacrolimus orally were analysed. The PopPK model explored the following covariates: weight, age, sex, type of transplant, age of liver donor, liver function tests, albumin, haematocrit, drug interactions, drug formulation and time post-transplantation. Optimal sampling strategies were developed and validated with jackknife. RESULTS A two-compartment model with first-order absorption and elimination and lag time described the data. Weight was included on all pharmacokinetic parameters. Typical apparent clearance and central volume of distribution were 12.1 l h(-1) and 31.3 l, respectively. The PopPK approach led to the development of optimal sampling strategies, which allowed estimation of tacrolimus pharmacokinetics and area under the concentration–time curve (AUC) on the basis of practical sampling schedules (three or four sampling times within 4 h) with clinically acceptable prediction error limit. The mean bias and precision of the Bayesian vs. reference (trapezoidal) AUCs ranged from -2.8 to -1.9% and from 7.4 to 12.5%, respectively. CONCLUSIONS The PopPK of tacrolimus and empirical Bayesian estimates represent an accurate and convenient method to predict tacrolimus AUC(0-12) in paediatric liver transplant recipients, despite high between-subject variability in pharmacokinetics and patient demographics. The developed optimal sampling strategies will allow the undertaking of prospective trials to define the tacrolimus AUC-based therapeutic window and dosing guidelines in this population.
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Sarem S, Li J, Barriere O, Litalien C, Théorêt Y, Lapeyraque AL, Nekka F. Bayesian approach for the estimation of cyclosporine area under the curve using limited sampling strategies in pediatric hematopoietic stem cell transplantation. Theor Biol Med Model 2014; 11:39. [PMID: 25192585 PMCID: PMC4237955 DOI: 10.1186/1742-4682-11-39] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 07/29/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The optimal marker for cyclosporine (CsA) monitoring in transplantation patients remains controversial. However, there is a growing interest in the use of the area under the concentration-time curve (AUC), particularly for cyclosporine dose adjustment in pediatric hematopoietic stem cell transplantation. In this paper, we develop Bayesian limited sampling strategies (B-LSS) for cyclosporine AUC estimation using population pharmacokinetic (Pop-PK) models and investigate related issues, with the aim to improve B-LSS prediction performance. METHODS Twenty five pediatric hematopoietic stem cell transplantation patients receiving intravenous and oral cyclosporine were investigated. Pop-PK analyses were carried out and the predictive performance of B-LSS was evaluated using the final Pop-PK model and several related ones. The performance of B-LSS when targeting different versions of AUC was also discussed. RESULTS A two-compartment structure model with a lag time and a combined additive and proportional error is retained. The final covariate model does not improve the B-LSS prediction performance. The best performing models for intravenous and oral cyclosporine are the structure ones with combined and additive error, respectively. Twelve B-LSS, consisting of 4 or less sampling points obtained within 4 hours post-dose, predict AUC with 95th percentile of the absolute values of relative prediction errors of 20% or less. Moreover, B-LSS perform better for the prediction of the 'underlying' AUC derived from the Pop-PK model estimated concentrations that exclude the residual errors, in comparison to their prediction of the observed AUC directly calculated using measured concentrations. CONCLUSIONS B-LSS can adequately estimate cyclosporine AUC. However, B-LSS performance is not perfectly in line with the standard Pop-PK model selection criteria; hence the final model might not be ideal for AUC prediction purpose. Therefore, for B-LSS application, Pop-PK model diagnostic criteria should additionally account for AUC prediction errors.
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Affiliation(s)
| | | | | | | | | | | | - Fahima Nekka
- Faculty of Pharmacy, Université de Montréal, C,P, 6128, Succ, Centre-ville, H3C 3J7 Montreal, Canada.
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Lapeyraque AL, Kassir N, Théorêt Y, Krajinovic M, Clermont MJ, Litalien C, Phan V. Conversion from twice- to once-daily tacrolimus in pediatric kidney recipients: a pharmacokinetic and bioequivalence study. Pediatr Nephrol 2014; 29:1081-8. [PMID: 24435759 PMCID: PMC4000411 DOI: 10.1007/s00467-013-2724-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 11/29/2013] [Accepted: 12/04/2013] [Indexed: 12/31/2022]
Abstract
BACKGROUND The objectives of this study were to investigate pharmacokinetic and pharmacogenetic parameters during the conversion on a 1:1 (mg:mg) basis from a twice-daily (Prograf) to once-daily (Advagraf) tacrolimus formulation in pediatric kidney transplant recipients. METHODS Twenty-four-hour pharmacokinetic profiles were analyzed before and after conversion in 19 stable renal transplant recipients (age 7-19 years). Tacrolimus pharmacokinetic parameters [area under the concentration-time curve (AUC0-24), minimum whole-blood concentration (Cmin), maximum whole-blood concentration (Cmax), and time to achieve maximum whole-blood concentration (tmax)] were compared between Tac formulations and between CYP3A5 and MDR1 genotypes after dose normalization. RESULTS Both AUC0-24 and Cmin decreased after conversion (223.3 to 197.5 ng.h/ml and 6.5 to 5.6 ng/ml; p = 0.03 and 0.01, respectively). However, the ratio of the least square means (LSM) for AUC0-24 was 90.8 %, with 90 % CI limits of 85.3 to 96.7 %, falling within bioequivalence limits. The CYP3A5 genotype influences the dose-normalized Cmin with the twice-daily formulation only. CONCLUSIONS Both tacrolimus formulations are bioequivalent in pediatric renal recipients. However, we observed a decrease in AUC0-24 and Cmin after the conversion, requiring close pharmacokinetic monitoring during the conversion period.
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Affiliation(s)
- Anne-Laure Lapeyraque
- Service de Néphrologie, Département de Pédiatrie, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada,
| | - Nastya Kassir
- Département de Pharmacie, Université de Montréal, Montréal, Canada
| | - Yves Théorêt
- Service de Néphrologie, Département de Pédiatrie, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada ,Unité de Pharmacologie Clinique, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada
| | - Maja Krajinovic
- Unité de Pharmacologie Clinique, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada
| | - Marie-José Clermont
- Service de Néphrologie, Département de Pédiatrie, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada
| | - Catherine Litalien
- Unité de Pharmacologie Clinique, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada
| | - Véronique Phan
- Service de Néphrologie, Département de Pédiatrie, CHU de Sainte-Justine, Université de Montréal, Montréal, Canada
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Uppugunduri C, Ansari M, Théorêt Y, Déglon J, Versace F, Gumy-Pause F, Dayer P, Desmeules J, Daali Y. Oc013 — A Simplified Method For Busulfan Therapeutic Drug Monitoring Using Dried Blood Spot Sampling In Pediatric Patient Undergoing Stem Cell Transplantation. Clin Ther 2013. [DOI: 10.1016/j.clinthera.2013.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Autmizguine J, Krajinovic M, Rousseau J, Théorêt Y, Litalien C, Marquis C, Tapiéro B, Ovetchkine P. Pharmacogenetics and beyond: variability of voriconazole plasma levels in a patient with primary immunodeficiency. Pharmacogenomics 2012; 13:1961-5. [DOI: 10.2217/pgs.12.175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report the case of a patient highly susceptible to invasive aspergillosis who received treatment with voriconazole (VRC). As part of therapeutic drug monitoring, VRC plasma trough concentrations were measured, showing undetectable levels (<0.16 µg/ml). Genotyping showed a heterozygous profile CYP2C19*1/*17, known to be associated with an ultrarapid-metabolism phenotype, contributing to the very low systemic exposure observed. Therefore, in this situation, the use of VRC treatment could be associated with therapeutic failure.
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Affiliation(s)
- Julie Autmizguine
- Infectious Diseases Division, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Department of Pediatrics, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
| | - Maja Krajinovic
- Department of Pediatrics, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Clinical Pharmacology Unit, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Research Center, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Department of Pharmacology, University of Montreal, Montreal (QC), Canada
| | - Julie Rousseau
- Research Center, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
| | - Yves Théorêt
- Clinical Pharmacology Unit, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Research Center, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Department of Pharmacology, University of Montreal, Montreal (QC), Canada
| | - Catherine Litalien
- Department of Pediatrics, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Clinical Pharmacology Unit, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Research Center, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Department of Pharmacology, University of Montreal, Montreal (QC), Canada
| | - Christopher Marquis
- Department of Pharmacy, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
| | - Bruce Tapiéro
- Infectious Diseases Division, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Department of Pediatrics, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
- Research Center, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
| | - Philippe Ovetchkine
- Infectious Diseases Division, CHU Sainte-Justine – University of Montreal, Montreal (QC), Canada
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Ansari M, Uppugunduri CRS, Déglon J, Théorêt Y, Versace F, Gumy-Pause F, Ozsahin H, Dayer P, Desmules J, Daali Y. A simplified method for busulfan monitoring using dried blood spot in combination with liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Spectrom 2012; 26:1437-1446. [PMID: 22592987 DOI: 10.1002/rcm.6241] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
RATIONALE Busulfan (Bu) is an important component of the myeloablative conditioning regimen prior to hematopoietic stem cell transplantation (HSCT) especially in children. Intravenously administered Bu exhibits a therapeutic window phenomenon requiring therapeutic drug monitoring. Analytical methods developed for Bu routine monitoring were aimed at using low volumes of biological fluids and development of simple procedures to facilitate the dosage adjustment. In this report, we describe a simple, rapid method for Bu measurement using dried blood spots (DBS) from only 5 μL of whole blood. METHODS Bu extracted from DBS with methanol was measured by high-performance liquid chromatography with electrospray ionization and tandem mass spectrometry in multiple reaction monitoring mode using D8-Bu as an internal standard. The method was in-house validated evaluating trueness, repeatability, within-laboratory reproducibility, specificity and the lower limit of quantification (LLOQ). RESULTS The method was linear in the calibration range of 100-2000 ng mL(-1) (r(2)>0.99) encompassing the therapeutic concentrations of Bu. A good trueness (<14%), precision (<10%), and recovery (100%) were observed during validation of the method with quality controls of 300, 600 and 1400 ng mL(-1). The LLOQ was determined as 50 ng mL(-1) and no matrix or carryover effects were observed. The validated method was applied to measure Bu levels in four children receiving infusion of Bu prior to HSCT. A good correlation was observed between the Bu levels measured by DBS and dried plasma spot (DPS) (r(2) =0.96) and between DPS and the GC/MS method (r(2) =0.92). Bu was found to be stable in DBS up to 6 h at room temperature and for 24 h at 4 °C. CONCLUSIONS The new DBS method facilitates earlier dosage adjustment during Bu therapy by its specific and simple procedure using 5 μL of whole blood.
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Affiliation(s)
- Marc Ansari
- Department of Pediatrics, Onco-hematology Unit, Geneva University Hospitals, Geneva, Switzerland
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Giroux PC, Salas-Prato M, Théorêt Y, Carmant L. Levetiracetam in children with refractory epilepsy: lack of correlation between plasma concentration and efficacy. Seizure 2009; 18:559-63. [PMID: 19546014 DOI: 10.1016/j.seizure.2009.05.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Revised: 05/11/2009] [Accepted: 05/15/2009] [Indexed: 10/20/2022] Open
Abstract
PURPOSE The goals of this study are to evaluate the efficacy and tolerability of levetiracetam (LEV) as add-on therapy in children with refractory epilepsies and to determine the value of LEV blood level monitoring in this population. METHODS Sixty-nine children (39 males and 30 females) treated with LEV between 2006 and 2007 were selected. Their medical files were reviewed for LEV efficacy and tolerability. In a subgroup of children currently taking LEV, plasma concentrations were determined by high performance liquid chromatography by ultraviolet detection (HPLC-UV) method and correlated with the given dose per kilo as well as clinical response. RESULTS Fifty-one patients (74%) had a more than 50% reduction in seizure frequency with 16 patients (23%) becoming seizure free on LEV. Eighteen (26%) patients had a less than 50% reduction in seizure frequency. Adverse events due to LEV ranged from mild to moderate in only 18 patients (26%). The most frequently observed were drowsiness, behavioral difficulties, increase in seizure frequency and headaches. The majority (60.5%) of the responders received doses between 10 and 50mg/kg/day and had a plasma concentration (PC) between 5 and 40microg/ml. However, we found no clear correlation between PC and efficacy. CONCLUSION Levetiracetam given twice a day in children with refractory epilepsy reduces seizure frequency in all types of epilepsy. In children, LEV is a broad spectrum anticonvulsant with a favourable safety profile.
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Affiliation(s)
- Patricia C Giroux
- Department of Physiology, University of Montreal, C.P. 6128, succursale Centre-ville, Montréal, Québec, Canada.
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Pettersen G, Mouksassi MS, Théorêt Y, Labbé L, Faure C, Nguyen B, Litalien C. Population pharmacokinetics of intravenous pantoprazole in paediatric intensive care patients. Br J Clin Pharmacol 2008; 67:216-27. [PMID: 19173681 DOI: 10.1111/j.1365-2125.2008.03328.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT The use of intravenous pantoprazole, a proton pump inhibitor, has been increasing in the paediatric intensive care unit. Despite this increased use, data on the disposition of intravenous pantoprazole in paediatric intensive care patients are very scarce. WHAT THIS STUDY ADDS Our population approach has determined the pharmacokinetic parameters of intravenous pantoprazole in paediatric intensive care patients and the relative importance of factors influencing its disposition. Pantoprazole clearance was significantly influenced by developmental changes and by the presence of systemic inflammatory syndrome, hepatic dysfunction and CYP2C19 inhibitors. AIMS To characterize the pharmacokinetics of intravenous pantoprazole in a paediatric intensive care population and to determine the influence of demographic factors, systemic inflammatory response syndrome (SIRS), hepatic dysfunction and concomitantly used CYP2C19 inducers and inhibitors on the drug's pharmacokinetics. METHODS A total of 156 pantoprazole concentration measurements from 20 patients (10 days to 16.4 years of age) at risk for or with upper gastrointestinal bleeding, who received pantoprazole doses ranging from 19.9 to 140.6 mg/1.73 m(2)/day, were analysed using a population pharmacokinetic approach (nonmem program). RESULTS The best structural model for pantoprazole was a two-compartment model with zero order infusion and first-order elimination. Body weight, SIRS, age, hepatic dysfunction and presence of CYP2C19 inhibitors were significant covariates affecting clearance (CL), accounting for 75% of interindividual variability. Only body weight significantly influenced central volume of distribution (V(c)). In the final population model, the estimated CL and V(c) were 5.28 l h(-1) and 2.22 l, respectively, for a typical 5-year-old child weighing 20 kg. Pantoprazole CL increased with weight and age, whereas the presence of SIRS, CYP2C19 inhibitors and hepatic dysfunction, when present separately, significantly decreased pantoprazole CL by 62.3, 65.8 and 50.5%, respectively. For patients aged between 6 months and 5 years without SIRS, CYP2C19 inhibitor or hepatic dysfunction, the predicted pantoprazole CL is faster than that reported in adults. CONCLUSION These results provide important information for physicians regarding selection of a starting dose and dosing regimens of pantoprazole for paediatric intensive care patients based on factors frequently encountered in this population.
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Affiliation(s)
- Géraldine Pettersen
- Clinical Pharmacology Unit, Department of Paediatrics, Divisions of Paediatric Critical Care, Centre Hospitalier Universitaire Sainte-Justine, 3175 chemin de la Côte Sainte-Catherine, Montréal, Québec, Canada
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Bussières JF, Théorêt Y, Prot-Labarthe S, Larocque D. Program to monitor surface contamination by methotrexate in a hematology–oncology satellite pharmacy. Am J Health Syst Pharm 2007; 64:531-5. [PMID: 17322167 DOI: 10.2146/ajhp060043] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The results of contamination monitoring during a one-year pilot period are described. SUMMARY A hematology-oncology satellite pharmacy conducted contamination monitoring for one year, using methotrexate as the index marker. From January 12, 2005, to December 21, 2005, 40 sampling sessions occurred during which 238 wipe samples (excluding positive controls) were collected. Each week, seven wipe samples were prepared by pharmacy technicians. Samples were obtained from the blank reference (site 0), the external metallic window frame of the main biological safety cabinet (BSC) (site 1), the back of the phone receiver (site 2), the external surface of an i.v. solution bag that was inside the BSC the previous hour (site 3), a working surface used for the final packaging and labeling (site 4), and the floor of the preparation room (site 5). The sixth sample was a positive methotrexate control. The methotrexate was detected by a high-performance liquid chromatograph with a fluorometric detector. Five samples tested positive for methotrexate-two from site 1, one from site 2, one from site 4, and one from site 0 (the blank); the last finding was thought to have most likely been the result of an error or sample mix-up during the wipe-sampling procedures. Despite differences in the sampling methods used, the type of wetting solution used, and the volume of desorption solution, the results were consistent with the literature in terms of few positive results. CONCLUSION A program was developed to monitor surface contamination by methotrexate in a hematology-oncology satellite pharmacy.
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Affiliation(s)
- Jean-François Bussières
- Department of Pharmacy, Centre Hospitalier Universitaire Sainte-Justine, 3175 Côte-Ste-Catherine, Montréal, Québec, Canada.
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Abstract
The use of proton pump inhibitors (PPIs) has become widespread in children and infants for the management of paediatric acid-related disease. Pharmacokinetic profiles of only omeprazole and lansoprazole have been well characterised in children over 2 years of age with acid-related diseases. Few data have been recently published regarding the pharmacokinetics of pantoprazole in children, and none are available for rabeprazole or esomeprazole. The metabolism of PPI enantiomers has never been studied in the paediatric population. A one-compartment model best describes the pharmacokinetic behaviour of omeprazole, lansoprazole and pantoprazole in children, with important interindividual variability for each pharmacokinetic parameter. Like adults, PPIs are rapidly absorbed in children following oral administration; the mean time to reach maximum plasma concentration varies from 1 to 3 hours. Since these agents are acid labile, their oral formulations consist of capsules containing enteric-coated granules. No liquid formulation is available for any of the PPIs. Thus, for those patients unable to swallow capsules, extemporaneous liquid preparations for omeprazole and lansoprazole have been reported; however, neither the absolute nor the relative bioavailabilities of these oral formulations have been studied in children. Intravenous formulations are available for omeprazole (in Europe), lansoprazole and pantoprazole. PPIs are rapidly metabolised in children, with short elimination half-lives of around 1 hour, similar to that reported for adults. All PPIs are extensively metabolised by the liver, primarily by cytochrome P450 (CYP) isoforms CYP2C19 and CYP3A4, to inactive metabolites, with little unchanged drug excreted in the urine. Similar to that seen in adults, the absolute bioavailability of omeprazole increases with repeated dosing in children; this phenomenon is thought to be due to a combination of decreased first-pass elimination and reduced systemic clearance. The apparent clearance (CL/F) of omeprazole, lansoprazole and pantoprazole appears to be faster for children than for adults. A higher metabolic capacity in children as well as differences in the extent of PPI bioavailability are most likely responsible for this finding. This may partly account for the need in children for variable and sometimes considerably greater doses of PPIs, on a per kilogram basis, than for adults to achieve similar plasma concentrations. Furthermore, no studies have been able to demonstrate a statistically significant correlation between age and pharmacokinetic parameters among children. Despite the small number of very young infants studied, there is some evidence for reduced PPI metabolism in newborns. The limited paediatric data regarding the impact of CYP2C19 genetic polymorphism on PPI metabolism are similar to those reported for adults, with poor metabolisers having 6- to 10-fold higher area under the concentration-time curve values compared with extensive metabolisers. Finally, because a pharmacokinetic/pharmacodynamic relationship exists for PPIs, the significant interindividual variability in their disposition may partly explain the wide range of therapeutic doses used in children. Further studies are needed to better define the pharmacokinetics of PPIs in children <2 years of age.
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Abstract
BACKGROUND AND OBJECTIVES The use of complementary and alternative medicines (CAM) is becoming increasingly popular. Although considered beneficial by users, the potential for interaction or substitution with conventional treatment should not be overlooked by health care professionals. It is therefore important to gain insight into the prevalence and the factors related to the use of CAM. To establish the prevalence of use of CAM among children with cancer treated in a large pediatric hospital, describe the profile of use and factors related with use. As a secondary objective we aimed at measuring quality of life of the children aged 5 or more and compare the scores between users and non-users. METHODS The study is a cross-sectional survey of parents whose child was treated at the oncology clinic or ward of Sainte-Justine Hospital, a large pediatric hospital in Montreal. Data on socio-demographic variables, the use of CAM and the quality of life was collected through a self-administered questionnaire. Quality of life was measured with the Child Health Questionnaire CHQ-PF50, while clinical data was collected from medical records. RESULTS A total of 115 patients were recruited and 92 parents completed and returned the questionnaire, resulting in a 80% response rate. According to this survey, 49% of the children used at least one type of CAM and 20% used herbal remedies/homeopathy/vitamins in the 2 months preceding the survey. Most popular CAM were spiritual/mental and physical strategies used by 35 and 33% of children under study, respectively. Only one parent reported having delayed a conventional treatment because of CAM. Although quality of life results must be interpreted with caution, they tend to favor non-users. CONCLUSIONS CAM is likely to be used by a wide variety of people. In our study, we found that about half of the children with cancer has used CAM in the 2 preceding months. No specific profile of CAM users emerged from this study. The high prevalence of CAM warrants further studies to better understand the reasons and consequences of CAM use particularly on quality of life.
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Affiliation(s)
- Dominique Martel
- Sainte-Justine Hospital, Department of Pharmacy, Montreal, Quebec
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Abstract
The purpose of this study was to evaluate the effect of basic fibroblastic growth factor (bFGF) on the growth of human UM-MB1 medulloblastoma xenografts injected intracranially in nude mice. Under general anesthesia, a homogenous suspension of UM-MB1 cells (10(5)/10 microl) were injected in the caudoputamen nuclei of the right cerebral hemisphere using a stereotaxic apparatus. The treatment group (n = 9) received 10 microl of a bFGF solution (20 microg/ml) at 3 and 6 days following the inoculation of the cells at the injection site using the same stereotaxic coordinates. The control group (n = 9) were injected intracranially with a phosphate-buffered saline vehicle using a similar protocol. Mice were sacrificed 3 weeks following the xenograft surgery and the brains were prepared for histological observations as well as tumor volume evaluations. The mean volume of bFGF-treated tumors (mean volume +/- SD = 50.0 +/- 32.9 +/- mm3) was significantly smaller than for the non-treated xenografts (mean volume +/- SD = 199.0 +/- 42.1 mm3) (t-test, p < 0.001). Compared to non-treated tumor cells, bFGF-treated medulloblastoma cells had a greater cytoplasm volume and their nuclei contained more euchromatin suggesting that bFGF may initiate differentiation. In conclusion, our results suggest that bFGF may offer a new chemotherapeutic modality for the treatment of medulloblastoma.
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Affiliation(s)
- Pascal Vachon
- Département de Biomédecine Vétérinaire, Faculté de Médecine Vétérinaire, Université de Montreal, St-Hyacinthe, QC, Canada.
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Gingras D, Gendron M, Boivin D, Moghrabi A, Théorêt Y, Béliveau R. Induction of medulloblastoma cell apoptosis by sulforaphane, a dietary anticarcinogen from Brassica vegetables. Cancer Lett 2004; 203:35-43. [PMID: 14670615 DOI: 10.1016/j.canlet.2003.08.025] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
There is increasing evidence that a variety of natural substances derived from the diet may act as potent chemopreventive agents. In this work, we show that DAOY cells, a widely used model of metastatic medulloblastoma (MBL), are highly sensitive to sulforaphane, a naturally occurring isothiocyanate from Brassica vegetables. Sulforaphane induced DAOY cell death by apoptosis, as determined by DNA fragmentation and chromatin condensation. DAOY apoptosis correlates with the induction of caspase-3 and -9 activities, resulting in the cleavage of PARP and vimentin. Both the cytotoxic effect and apoptotic characteristics induced by sulforaphane were reversed by zVAD-fmk, a broad spectrum caspase inhibitor, demonstrating the important role of caspases in its cytotoxic effect. These results identify sulforaphane as a novel inducer of MBL cell apoptosis, supporting the potential clinical usefulness of diet-derived substances as chemopreventive agents.
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Affiliation(s)
- Denis Gingras
- Centre de Cancérologie Charles-Bruneau, Hôpital Ste-Justine, 3175 Chemin Côte-Ste-Catherine, H3T 1C5 Montréal, Que., Canada
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Abstract
BACKGROUND Moderate hyperhomocysteinemia is considered a risk factor for thrombosis and atherosclerosis. We hypothesized that higher maternal and newborn homocysteine concentrations in plasma would increase the risk of intrauterine growth restriction through placental thrombosis. METHODS We carried out a case-control study that included all cases born at our institution over a 2-year period whose birthweight was below the 10th percentiles for gestational age and sex according to Canadian norms; controls were born at the same period and institution at or above the 10th percentiles and were matched on gestational age, race, and sex. Homocysteine was measured in cord and maternal blood. The analysis included 483 case and 468 control mothers and 409 case and 438 control newborns. RESULTS Homocysteine values were largely <15 micromol/L. Contrary to expectation, within that range of values, increased plasma homocysteine, particularly in the mother, was protective against intrauterine growth restriction. With the case/control status as the outcome, the estimated odds ratio was 0.37 (95% confidence interval, 0.24-0.58) for a 5 micromol/L unit difference on the maternal homocysteine scale. With birthweight as the outcome, the estimated increase was 178.1 g (95% confidence interval, 92.5-263.7 g) for every 5 micromol/L unit increase in maternal homocysteine. Results were similar using newborn homocysteine concentrations. CONCLUSIONS The data suggest that, in contrast to the proposed hypothesis, mothers with small babies have lower homocysteine concentrations than those giving birth to larger ones.
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Affiliation(s)
- Claire Infante-Rivard
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montréal, Province of Québec, H3A 1A3 Canada.
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Abstract
BACKGROUND Typical assay methods for total homocysteine in human plasma involve EDTA-containing whole blood. Unfortunately, rapid increases of the plasma homocysteine concentrations due to cellular export are observed when the EDTA-containing samples are not stored on ice and processed shortly after collection. This is a cumbersome procedure in perinatal settings, whereby delivery usually takes place at unpredictable times. METHODS The stability of homocysteine was assessed from six placental and neonatal blood samples collected in citrate buffer. Samples were stored at 4 degrees C and tested at regular intervals for the first 24 h. RESULTS There was no statistical difference in homocysteine concentrations as observed over the study storage period (mean coefficient of variation [CV] 4.9%). CONCLUSIONS Citrated samples can be left in a refrigerator for at least 24 h with no effect on the plasma homocysteine concentrations.
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Affiliation(s)
- Yves Théorêt
- Département de Pharmacologie, Université de Montreal, Quebec, Canada
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Duplan SM, Théorêt Y, Kenigsberg RL. Antitumor activity of fibroblast growth factors (FGFs) for medulloblastoma may correlate with FGF receptor expression and tumor variant. Clin Cancer Res 2002; 8:246-57. [PMID: 11801566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Members of the fibroblast growth factor (FGF) family, which normally control cerebellar neuronal maturation, may represent more natural and less toxic tools with which to target medulloblastoma (MB), an embryonal brain tumor thought to arise from cerebellar neuronal precursors. In support of this, we found previously basic FGF/FGF-2 can inhibit MB progression by inducing neuronal-like differentiation, slowing the growth, and triggering apoptosis of a MB cell line we established from a histopathologically classic tumor (R. L. Kenigsberg et al., Am. J. Pathol., 151: 867-881, 1997). In the present study, the usefulness of this approach is additionally investigated. We report that of the five FGFs found in the developing cerebellum, only two, FGF-2 and FGF-9, possess antitumoral activity for MB. This activity is only noted for cell lines that originate from classic (UM-MB1 and SYR) rather than desmoplastic (HSJ) tumors. Whereas these FGFs inhibit proliferation of both classic cell lines, they only advance neuronal differentiation and induce apoptosis of one, UM-MB1. Consistent with these responses, after FGF treatment, levels of neurofilaments and the proapoptotic modulator Bax only increase in UM-MB1, whereas the cyclin-dependent kinase inhibitor p27/Kip1 (p27), which accumulates in cerebellar neuronal precursors before they exit the cell cycle, goes up in both UM-MB1 and SYR. Finally, although the histological variant of MB may help predict the sensitivity of MB to the FGFs, the selectivity, specificity, and type of response elicited may be dictated by, as evident by immunoprecipitation and Western blot analyses, the expression of certain FGF receptor types.
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Affiliation(s)
- Sabine M Duplan
- Developmental Neurobiology Group, Research Center, St. Justine's Hospital, Montreal, Quebec, Canada H3T 1C5
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Dubinsky MC, Lamothe S, Yang HY, Targan SR, Sinnett D, Théorêt Y, Seidman EG. Pharmacogenomics and metabolite measurement for 6-mercaptopurine therapy in inflammatory bowel disease. Gastroenterology 2000; 118:705-13. [PMID: 10734022 DOI: 10.1016/s0016-5085(00)70140-5] [Citation(s) in RCA: 705] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS The effects of 6-mercaptopurine (6-MP) are mediated via its intracellular conversion to 6-thioguanine (6-TG) and 6-methylmercaptopurine (6-MMP) nucleotide metabolites, the latter genetically controlled by thiopurine methyltransferase (TPMT). We sought to determine optimal therapeutic 6-MP metabolite levels and their correlation with medication-induced toxicity and TPMT genotype. METHODS Therapeutic response was determined in 92 pediatric patients with inflammatory bowel disease coincidentally with hematologic, pancreatic, and hepatic laboratory parameters, and compared with erythrocyte metabolite levels and TPMT genotype. RESULTS Clinical response was highly correlated with 6-TG levels (P < 0.0001) but not with any other variable, including 6-MMP levels, drug dose, gender, and concurrent medications. The frequency of therapeutic response increased at 6-TG levels > 235 pmol/8 x 10(8) erythrocytes (P < 0.001). Hepatotoxicity correlated with elevated 6-MMP levels (>5700 pmol/8 x 10(8) erythrocytes; P < 0.05). Although leukopenia was associated with higher 6-TG levels (P < 0.03), it was observed in only 8% of responders. Patients heterozygous for TPMT (8/92) had higher 6-TG levels (P < 0.0001), and all responded to therapy. CONCLUSIONS 6-MP metabolite levels and TPMT genotyping may assist clinicians in optimizing therapeutic response to 6-MP and identifying individuals at increased risk for drug-induced toxicity.
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Affiliation(s)
- M C Dubinsky
- Division of Gastroenterology and Nutrition, University of Montréal, Montréal, Québec, Canada
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Kenigsberg RL, Hong Y, Théorêt Y. Cholinergic cell expression in the developing rat medial septal nucleus in vitro is differentially controlled by GABAA and GABAB receptors. Brain Res 1998; 805:123-30. [PMID: 9733945 DOI: 10.1016/s0006-8993(98)00690-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The early appearance and relative abundance of GABAergic neurons in basal forebrain cholinergic nuclei like the medial septum suggest that the maturation of the later developing cholinergic neurons in these nuclei may be controlled by GABA. To examine this possibility, the effects of both exogenous GABA and specific GABA receptor agonists, as well as that of endogenous GABA on the phenotypic expression and survival of the cholinergic neurons in primary cultures from the fetal rat medial septum, were studied. Treatment of these cultures for six days with GABA significantly decreased the enzymatic activity of choline acetyltransferase (EC 2.3.1.6) (ChAT) in a dose-dependent manner. This response to exogenous GABA was blocked by bicuculline, mimicked by muscimol and slightly potentiated by saclofen. Consistent with this latter observation, the GABAB receptor agonist, baclofen, dose-dependently increased septal ChAT activity. However, while the effect of baclofen on cholinergic expression was lost in the absence of glia, the suppressive effects of GABA or muscimol were more marked. Acetylcholinesterase (EC 3.1.1.7) (AChE) expression in mixed neuronal-glial cultures, was, like ChAT activity, increased or decreased in intensity with the inclusion of baclofen or muscimol, respectively. Although the number of AChE positive neurons in muscimol-treated cultures was significantly lower than that in controls, no changes in neither neuronal nor general cell viability were noted. Finally, as GABAA or GABAB receptor antagonists bicuculline and picrotoxin or saclofen, when applied alone to mixed cultures, increased or decreased ChAT activity, respectively, it appears that endogenous GABA, tonically released in the developing septum, may, via specific receptor types, differentially control the biochemical maturation of the cholinergic neurons.
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Affiliation(s)
- R L Kenigsberg
- Department of Pediatrics, Research Center, St. Justine's Hospital, Montreal, Quebec, Canada.
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Kenigsberg RL, Hong Y, Yao H, Lemieux N, Michaud J, Tautu C, Théorêt Y. Effects of basic fibroblast growth factor on the differentiation, growth, and viability of a new human medulloblastoma cell line (UM-MB1). Am J Pathol 1997; 151:867-81. [PMID: 9284836 PMCID: PMC1857835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We presently report the effects of human recombinant basic fibroblast growth factor (bFGF) on a newly established medulloblastoma cell line, UM-MB1. This predominantly adherent cell line has a mean doubling time of 39.3 hours and was found, by karyotypic analysis, to be near triploid. UM-MB1 consists of undifferentiated cells expressing markers of neuronal lineage such as the three neurofilament subunits as well as neuron-specific enolase, synaptophysin, and microtubule-associated proteins 1 and 5. In contrast, no immunoreactivity for glial fibrillary acidic protein was evident. When exposed to nanomolar amounts of bFGF, UM-MB1 cells began to extend neurite-like processes with arborizations and growth-cone-like structures. In addition, UM-MB1 cells treated with bFGF exhibited ultrastructural alterations that reflect their enhanced differentiation as well as the increased expression of at least one of the neurofilament subunits as evidenced both immunocytochemically and on Western blots. Furthermore, bFGF significantly decreased UM-MB1 cell growth as well as induced their death. UM-MB1 cells treated with bFGF for several days displayed DNA cleavage, nuclear shrinkage, and chromatin condensation while retaining their cytoplasmic and mitochondrial membrane integrity, all early indices of apoptosis. After this, cell death was evident with the concomitant appearance of the classical apoptotic bodies. By flow cytometry, bFGF was found to increase the proportion of cells in G1 before inducing their death by apoptosis. In conclusion, UM-MB1 cells can, when appropriately stimulated, be induced to differentiate along their neuronal lineage pathway. Their differentiation induced by bFGF, although incomplete, appears to promote or inhibit the expression of apoptotic effectors or suppressors in these cells, respectively, so to induce their death by an apoptotic-like mechanism.
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Affiliation(s)
- R L Kenigsberg
- Department of Pediatrics, Ste-justine's Hospital, Montreal, Quebec, Canada
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Abstract
BACKGROUND 6-Mercaptopurine (6-MP) has confirmed short and longterm efficacy in the treatment of IBD. However, the relation between its metabolism, efficacy, and side effects is not well understood. AIMS To assay 6-MP metabolites and to correlate levels with drug compliance, disease activity, and adverse effects of treatment. PATIENTS Heparinised blood was obtained prior to daily administration of 6-MP in 25 adolescent Crohn's disease patients (14 ileocolitis, 11 colitis) receiving 1.2 (range 0.4-1.6) mg/kg/day for a mean of 17 (range 4-65) months. METHODS Erythrocyte free bases 6-thioguanine (6-TG) and 6-methyl-mercaptopurine (6-MMP) were measured (pmol/8 x 10(8) red blood cells) using reverse phase high performance liquid chromatography. RESULTS Disease activity (modified Harvey-Bradshaw index) improved significantly with 6-MP (p = 0.001). Clinical remission was achieved in 72% of patients, who stopped taking prednisone, or were successfully weaned to a low alternate day dose (< 0.4 mg/kg/OD). Remission correlated well with erythrocyte 6-TG (p < 0.05), but not 6-MMP levels. Neutropenia was associated with 6-MP use (p < 0.005), but did not correlate with erythrocyte 6-MP metabolite levels. One patient refractory to 6-MP had 6-TG, but no measureable 6-MMP production, suggesting deficient thiopurine methyl-transferase activity or poor compliance. 6-MP induced complications (hepatitis, pancreatitis, and marrow suppression) were generally associated with increased 6-MMP levels. CONCLUSIONS These results suggest that high performance liquid chromatography measurement of erythrocyte 6-MP metabolites may provide a quantitative assessment of patient responsiveness and compliance to treatment. The data support an immunosuppressive role for 6-TG, and potential cytotoxicity of raised 6-MMP levels.
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Affiliation(s)
- C Cuffari
- Department of Pediatrics, Université de Montréal, Canada
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Cuffari C, Seidman EG, Latour S, Théorêt Y. Quantitation of 6-thioguanine in peripheral blood leukocyte DNA in Crohn's disease patients on maintenance 6-mercaptopurine therapy. Can J Physiol Pharmacol 1996; 74:580-5. [PMID: 8884023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of 6-mercaptopurine (6MP) in inflammatory bowel disease are believed to be primarily mediated by its metabolite 6-thioguanine (6TG). Our aim was to develop an assay for measuring leukocyte DNA 6TG levels in patients with Crohn's disease, and to correlate them with levels of 6TG in erythrocytes. Heparinized blood was obtained from 15 adolescent Crohn's disease patients receiving 6MP at an average dose of 1.3 mg.kg-1 day-1 (range 0.8-1.6 mg.kg-1 day-1) for a mean of 23.7 months (range 3-71 months). Leukocyte DNA and erythrocyte 6TG levels were measured by an HPLC assay. Leukocyte 6TG levels ranged from 100 to 2305 pmol/mg DNA, while erythrocyte 6TG levels ranged from 64 to 1038 pmol/8 x 10(8) red blood cells, demonstrating significant interpatient variability. Leukocyte DNA 6TG levels correlated directly with erythrocyte 6TG levels, as measured by the Spearman rank correlation coefficient (p < 0.05). The HPLC measurement of erythrocyte and leukocyte DNA 6TG levels can be useful clinically in monitoring compliance, as well as perhaps to tailor drug metabolite levels to achieve the desired clinical effect.
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Affiliation(s)
- C Cuffari
- Department of Pediatrics, Hôpital Sainte-Justine, Université de Montréal, QC, Canada
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Cuffari C, Seidman EG, Latour S, Théorêt Y. Quantitation of 6-thioguanine in peripheral blood leukocyte DNA in Crohn's disease patients on maintenance 6-mercaptopurine therapy. Can J Physiol Pharmacol 1996. [DOI: 10.1139/y96-056] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Théorêt Y, Varin F. Simple, rapid and selective method using high-performance liquid chromatography for the determination of bretylium in plasma. J Chromatogr 1992; 575:162-6. [PMID: 1517295 DOI: 10.1016/0378-4347(92)80519-v] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A high-performance liquid chromatographic method with ultraviolet detection has been developed for the determination of bretylium in plasma. Following a single-step solid-phase extraction procedure, bretylium is selectively isolated and well recovered from plasma. The assay sensitivity is 0.156 micrograms/ml from 250-microliters plasma samples and its linearity was assessed up to 40 micrograms/ml. The method is accurate (101.0 +/- 5.4%) and precise (maximum coefficient of variation of 8%). It provides a simple and time-saving alternative to existing methods and is particularly suitable for pharmacokinetic studies.
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Affiliation(s)
- Y Théorêt
- Département de Pharmacologie, Faculté de Médicine, Université de Montréal, Canada
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Varin F, The Minh TU, Benoît F, Villeneuve JP, Théorêt Y. High-performance liquid chromatographic determination of spironolactone and its metabolites in human biological fluids after solid-phase extraction. J Chromatogr 1992; 574:57-64. [PMID: 1629288 DOI: 10.1016/0378-4347(92)80097-a] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A simple and sensitive high-performance liquid chromatographic procedure to determine spironolactone and its three major metabolites in biological specimens is described. The assay involves sequential extraction on C18 and CN solid phases, and subsequent separation on a reversed-phase column. In plasma samples, spironolactone and its metabolites were completely separated within 8 min using an isocratic mobile phase, while in urine samples a methanol gradient was necessary to achieve a good separation within 14 min. Recoveries for all analytes were greater than 80% in plasma and 72% in urine. Linear responses were observed for all compounds in the range 6.25-400 ng/ml for plasma and 31.25-2000 ng/ml for urine. The plasma and urine methods were precise (coefficient of variation from 0.8 to 12.5%) and accurate (-12.1% to 7.4% of the nominal values) for all compounds. The assay proved to be suitable for the pharmacokinetic study of spironolactone in healthy human subjects.
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Affiliation(s)
- F Varin
- Faculté de Pharmacie, Université de Montréal, Canada
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46
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Ducharme J, Varin F, Bevan DR, Donati F, Théorêt Y. High-performance liquid chromatography—electrochemical detection of vecuronium and its metabolites in human plasma. ACTA ACUST UNITED AC 1992; 573:79-86. [PMID: 1348748 DOI: 10.1016/0378-4347(92)80477-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A high-performance liquid chromatographic assay coupled with electrochemical detection has been developed for the determination of vecuronium and its three putative deacetylated metabolites in human plasma. A novel solid-phase extraction procedure allowed good recovery of both vecuronium and its metabolites, together with ease and speed of execution. This method was sensitive, reproducible and accurate over the therapeutic range of concentrations of vecuronium and its metabolites, and was applied successfully to a study of the pharmacokinetics of vecuronium in anaesthetized patients.
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Affiliation(s)
- J Ducharme
- Faculté de Pharmacie, Université de Montréal, Quebec, Canada
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47
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Donati F, Varin F, Ducharme J, Gill SS, Théorêt Y, Bevan DR. Pharmacokinetics and pharmacodynamics of atracurium obtained with arterial and venous blood samples. Clin Pharmacol Ther 1991; 49:515-22. [PMID: 2029828 DOI: 10.1038/clpt.1991.62] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To determine the influence of sampling site on atracurium pharmacokinetic-pharmacodynamic relationships, blood was drawn simultaneously from the radial artery and peripheral vein during a 20-minute period after injection of atracurium, 0.2 mg/kg, in eight patients. Atracurium and laudanosine concentrations were measured by HPLC. Neuromuscular blockade was measured at the adductor pollicis, after stimulation of the ulnar nerve. Venous levels were lower than corresponding arterial values for up to 20 minutes, and this difference was marked for the early samples. Neuromuscular blockade was maximum after 5 to 7 minutes, much later than the peak venous concentration (1 to 3 minutes). Nonparametric analysis yielded (mean +/- SEM) a rate constant, concentration for 50% blockade, and slope of the effect-concentration relationship of 0.092 +/- 0.01 min-1, 379 +/- 27 ng/ml, and 7.3 +/- 1.67, respectively, when based on arterial samples. The values were statistically different (0.135 +/- 0.011 min-1, 235 +/- 42 ng/ml, and 3.41 +/- 0.37, respectively) when venous levels were used (p less than 0.05). It is concluded that forearm venous levels do not correspond to adductor pollicis neuromuscular blockade and the kinetics and kinetic-dynamic relationship for atracurium are heavily dependent on sampling site.
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Affiliation(s)
- F Donati
- Department of Anaesthesia, Royal Victoria Hospital, Montréal, Québec, Canada
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Varin F, Ducharme J, Besner JG, Théorêt Y. Determination of atracurium and laudanosine in human plasma by high-performance liquid chromatography. J Chromatogr 1990; 529:319-27. [PMID: 2229251 DOI: 10.1016/s0378-4347(00)83838-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A high-performance liquid chromatographic method coupled with fluorometric detection has been developed for the determination of atracurium and its major end-product laudanosine in human plasma. The method enables good separation of atracurium from its metabolites after direct precipitation of plasma proteins. The assay is sensitive, reproducible and linear for atracurium concentrations ranging from 31.25 to 8000 ng/ml. In a clinical setting, drugs commonly administered during anesthesia did not interfere with the assay. This method provides a simple and time-saving alternative to existing methods.
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Affiliation(s)
- F Varin
- Faculté de Pharmacie, Université de Montréal, Quebec, Canada
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49
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Varin F, Ducharme J, Théorêt Y, Besner JG, Bevan DR, Donati F. Influence of extreme obesity on the body disposition and neuromuscular blocking effect of atracurium. Clin Pharmacol Ther 1990; 48:18-25. [PMID: 2369806 DOI: 10.1038/clpt.1990.112] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The pharmacokinetics and pharmacodynamics of atracurium, a nondepolarizing neuromuscular blocking agent, were compared between morbidly obese patients and nonobese patients. Atracurium besylate (0.2 mg/kg) was administered intravenously as a bolus to patients who had received anesthesia. The force of contraction of the adductor pollicis was measured and plasma samples were collected for a 2-hour period. The concentrations of atracurium and its major end product, laudanosine, were determined by use of a chromatographic method. The pharmacokinetic-pharmacodynamic relationship was characterized by use of several models. No difference was observed between obese patients and nonobese patients in atracurium elimination half-life (19.8 +/- 0.7 versus 19.7 +/- 0.7 minutes), volume of distribution at steady state (8.6 +/- 0.7 versus 8.5 +/- 0.7 L), and total clearance (444 +/- 29 versus 404 +/- 25 ml/min). However, if values were expressed on a total body weight basis, there was a difference between obese and nonobese patients in the volume of distribution at steady state (0.067 versus 0.141 L/kg) and total clearance (3.5 +/- 0.2 versus 6.6 +/- 0.5 ml/min/kg). Although atracurium concentrations were consistently higher in obese patients than in nonobese patients, there was no difference in the time of recovery from neuromuscular blockade between the two groups. Consequently, the median effective concentration was higher in obese than in nonobese patients (470 +/- 46 versus 312 +/- 33 ng/ml).
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Affiliation(s)
- F Varin
- Faculté de Pharmacie, Université de Montréal, Québec, Canada
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Caillé G, Dubé LM, Théorêt Y, Varin F, Mousseau N, McGilveray IJ. Stability study of diltiazem and two of its metabolites using a high performance liquid chromatographic method. Biopharm Drug Dispos 1989; 10:107-14. [PMID: 2923956 DOI: 10.1002/bdd.2510100112] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- G Caillé
- Département de Pharmacologie, Faculté de Médecine, Université de Montreal, Québec, Canada
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