1
|
De Las Cuevas C, Sanz EJ, Gross JA, Correll CU, Verdoux H, Lally J, de Filippis R, Schulte PFJ, Molden E, Arrojo-Romero M, Bostrom AD, Schoretsanitis G, Fernandez-Egea E, de Leon J. Revealing the reporting disparity: VigiBase highlights underreporting of clozapine in other Western European countries compared to the UK. Schizophr Res 2024; 268:175-188. [PMID: 38065799 DOI: 10.1016/j.schres.2023.11.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 11/17/2023] [Accepted: 11/22/2023] [Indexed: 06/15/2024]
Abstract
BACKGROUND Pharmacovigilance studies indicate clozapine history is marked by adverse drug reactions (ADRs). OBJECTIVE In a 2021 article, the United Kingdom (UK) had >90 % of European clozapine-related fatal outcomes in VigiBase, the World Health Organization's pharmacovigilance database. Two possibly opposing hypotheses could explain this disparity: 1) fewer reported fatal outcomes in other Western European countries mainly reflect underreporting to VigiBase, and 2) the higher number of UK reports reflects higher real relative mortality. METHODS VigiBase reports from clozapine's introduction to December 31, 2022, were studied for ADRs and the top 10 causes of fatal outcomes. The UK was compared with 11 other top reporting Western countries (Germany, Denmark, France, Finland, Ireland, Italy, Netherlands, Norway, Spain, Sweden and Switzerland). Nine countries (except Ireland and Switzerland) were compared after controlling for population and clozapine prescriptions. RESULTS The UK accounted for 29 % of worldwide clozapine-related fatal outcomes, Germany 2 % and <1 % in each of the other countries. The nonspecific label "death" was the top cause in the world (46 %) and in the UK (33 %). "Pneumonia" was second in the world (8 %), the UK (12 %), Ireland (8 %) and Finland (14 %). Assuming that our corrections for population and clozapine use are correct, other countries underreported only 1-10 % of the UK clozapine fatal outcome number. CONCLUSIONS Different Western European countries consistently underreport to VigiBase compared to the UK, but have different reporting/publishing styles for clozapine-related ADRs/fatal outcomes. Three Scandinavian registries suggest lives are saved as clozapine use increases, but this cannot be studied in pharmacovigilance databases.
Collapse
Affiliation(s)
- Carlos De Las Cuevas
- Department of Internal Medicine, Dermatology and Psychiatry, School of Medicine, University of La Laguna, Canary Islands, Spain; Instituto Universitario de Neurociencia (IUNE), Universidad de La Laguna, San Cristóbal de La Laguna, Spain.
| | - Emilio J Sanz
- Department of Physical Medicine and Pharmacology, School of Medicine, Universidad de La Laguna, Canary Islands, Spain; Hospital Universitario de Canarias, Tenerife, Spain
| | | | - Christoph U Correll
- Department of Child and Adolescent Psychiatry, Charité Universitätsmedizin, Berlin, Germany; The Zucker Hillside Hospital, Psychiatry Research, Northwell Health, Glen Oaks, NY, USA; Department of Psychiatry, Zucker School of Medicine at Northwell/Hofstra, Hempstead, NY, USA.
| | - Hélène Verdoux
- Université Bordeaux, Inserm, Bordeaux Population Health Research Center, Team Pharmacoepidemiology, Bordeaux, France.
| | - John Lally
- Department of Psychiatry, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland.; Department of Psychiatry, St Vincent's Hospital Fairview, Dublin, Ireland; Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, UK.
| | - Renato de Filippis
- Psychiatry Unit, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Peter F J Schulte
- Mental Health Services Noord-Holland-Noord, Alkmaar, the Netherlands; Dutch Clozapine Collaboration Group, Castricum, the Netherlands.
| | - Espen Molden
- Center for Psychopharmacology, Diakonhjemmet Hospital, Oslo, Norway; Department of Pharmacy, University of Oslo, Oslo, Norway.
| | - Manuel Arrojo-Romero
- Department of Psychiatry, Complejo Hospitalario Universitario de Santiago, Santiago de Compostela, Spain.
| | - Adrian D Bostrom
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Clinical Sciences/Psychiatry, Umeå University, Umeå, Sweden.
| | - Georgios Schoretsanitis
- The Zucker Hillside Hospital, Psychiatry Research, Northwell Health, Glen Oaks, NY, USA; Department of Psychiatry, Zucker School of Medicine at Northwell/Hofstra, Hempstead, NY, USA; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zürich, Zürich, Switzerland
| | - Emilio Fernandez-Egea
- Department of Psychiatry, University of Cambridge, Cambridge, UK,; Cambridgeshire and Peterborough NHS Foundation Trust, Fulbourn Hospital, Fulbourn, Cambridge, UK.
| | - Jose de Leon
- Mental Health Research Center at Eastern State Hospital, Lexington, KY, USA; Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apostol Hospital, University of the Basque Country, Vitoria, Spain.
| |
Collapse
|
2
|
Jia F, Zang YN, Ruan CJ, Chi L, Zhuang HY, Wan Z, Yang Q, de Leon J. A Chinese medicine called Danggui Longhui may be a new clinically relevant clozapine inducer: Two case reports identified by therapeutic drug monitoring. Schizophr Res 2024; 268:308-311. [PMID: 37775404 DOI: 10.1016/j.schres.2023.09.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 09/12/2023] [Accepted: 09/14/2023] [Indexed: 10/01/2023]
Abstract
BACKGROUND Danggui Longhui is a traditional Chinese medicine made from the dried root of Angelica sinensis. It is used in psychiatric patients in China to reduce associated constipation. In a population pharmacokinetic model in olanzapine patients from Beijing Anding Hospital, we demonstrate that dangguilonghui tablets doubled olanzapine clearance, indicating the induction of olanzapine metabolism. Olanzapine metabolism is similar to clozapine metabolism. METHODS Two cases of possible clozapine induction using dangguilonghui tablets 4 g/day were identified in Beijing Anding Hospital. Dividing the minimum therapeutic concentration of 350 ng/mL by the concentration-to-dose (C/D) ratio provides the minimum therapeutic dose. RESULTS Case 1 was a female smoker on clozapine for 415 days. The mean of 6 clozapine C/D ratios associated with smoking provided a minimum therapeutic dose of 267 mg/day. There were 6 steady-state concentrations on the combination of valproic acid and dangguilonghui tablets, which provided a much higher minimum therapeutic dose of 833 mg/day. Four steady-state clozapine C/D ratios based on smoking and valproate after 4 months of carbamazepine 200 mg/day provided a minimum therapeutic dose of 603 mg/day. Case 2 was a female non-smoker on clozapine for 58 days. She had 3 clozapine C/D ratios on dangguilonghui tablets with a mean of 0.30 ng/mL providing a minimum therapeutic dose of 1167 mg/day. CONCLUSION Future clinical studies with repeated measures need to replicate the possibility that dangguilonghui tablets are a moderate-to-strong inducer of clozapine metabolism as suggested by these two limited cases.
Collapse
Affiliation(s)
- Fei Jia
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.
| | - Yan-Nan Zang
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Can-Jun Ruan
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.
| | - Li Chi
- School of Traditional Chinese Medicine, Capital Medical University, Beijing, China.
| | - Hong-Yan Zhuang
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Zhou Wan
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Qi Yang
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Jose de Leon
- Mental Health Research Center, Eastern State Hospital, Lexington, KY, USA; Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apóstol Hospital, University of the Basque Country, Vitoria, Spain.
| |
Collapse
|
3
|
Schoretsanitis G, Anıl Yağcıoğlu AE, Ruan CJ, Eap CB, Molden E, Baptista T, Clark SR, Fernandez-Egea E, Kim SH, Lane HY, Leung J, Maroñas Amigo O, Motuca M, Olmos I, Every-Palmer S, Procyshyn RM, Rohde C, Satish S, Schulte PFJ, Spina E, Takeuchi H, Verdoux H, Correll CU, de Leon J. Clozapine ultrarapid metabolism during weak induction probably exists but requires careful diagnosis. A literature review, five new cases and a proposed definition. Schizophr Res 2024; 268:302-307. [PMID: 37268453 DOI: 10.1016/j.schres.2023.05.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 06/04/2023]
Abstract
During weak induction (from smoking and/or valproate co-prescription), clozapine ultrarapid metabolizers (UMs) need very high daily doses to reach the minimum therapeutic concentration of 350 ng/ml in plasma; clozapine UMs need clozapine doses higher than: 1) 900 mg/day in patients of European/African ancestry, or 2) 600 mg/day in those of Asian ancestry. Published clozapine UMs include 10 males of European/African ancestry, mainly assessed with single concentrations. Five new clozapine UMs (two of European and three of Asian ancestry) with repeated assessments are described. A US double-blind randomized trial included a 32-year-old male smoking two packages/day with a minimum therapeutic dose of 1,591 mg/day from a single TDM during open treatment of 900 mg/day. In a Turkish inpatient study, a 30-year-old male smoker was a possible clozapine UM needing a minimum therapeutic dose of 1,029 mg/day estimated from two trough steady-state concentrations on 600 mg/day. In a Chinese study, three possible clozapine UMs (all male smokers) were identified. The clozapine minimum therapeutic dose estimated with trough steady-state concentrations >150 ng/ml was: 1) 625 mg/day, based on a mean of 20 concentrations in Case 3; 2) 673 mg/day, based on a mean of 4 concentrations in Case 4; and 3) 648 mg/day, based on a mean of 11 concentrations in Case 5. Based on these limited studies, clozapine UMs during weak induction may account for 1-2% of clozapine-treated patients of European ancestry and <1% of those of Asian ancestry. A clozapine-to-norclozapine ratio <0.5 should not be used to identify clozapine UMs.
Collapse
Affiliation(s)
- Georgios Schoretsanitis
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zürich, Zürich, Switzerland; Division of Psychiatry Research, Northwell Health, The Zucker Hillside Hospital, New York, NY, USA; Department of Psychiatry and Molecular Medicine, The Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, New York, NY, USA.
| | | | - Can-Jun Ruan
- The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China; Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China.
| | - Chin B Eap
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland; School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland; Center for Research and Innovation in Clinical Pharmaceutical Sciences, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, University of Lausanne, Geneva, Switzerland.
| | - Espen Molden
- Center for Psychopharmacology, Diakonhjemmet Hospital, PO Box 23 Vinderen, 0319 Oslo, Norway; Department of Pharmacy, University of Oslo, Oslo, Norway.
| | - Trino Baptista
- Department of Physiology, Los Andes University Medical School, Mérida, Venezuela; Medical School, Anáhuac University, Querétaro, Mexico; Neuroorigen, Querétaro, Mexico
| | - Scott R Clark
- University of Adelaide, Discipline of Psychiatry, Adelaide, Australia.
| | - Emilio Fernandez-Egea
- Department of Psychiatry, University of Cambridge, Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Fulbourn Hospital, Fulbourn, Cambridge, UK.
| | - Se Hyun Kim
- Department of Psychiatry, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea.
| | - Hsien-Yuan Lane
- Department of Psychiatry and Brain Disease Research Center, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan; Department of Psychology, College of Medical and Health Sciences, Asia University, Taichung, Taiwan
| | - Jonathan Leung
- Department of Pharmacy, Mayo Clinic, Rochester, MN, USA.
| | - Olalla Maroñas Amigo
- Genomic Medicine Group, Galician Public Foundation of Genomic Medicine (FPGMX), Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Galicia, Spain; Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), University of Santiago de Compostela (USC), Santiago de Compostela, Spain; Center for Biomedical Research in Rare Diseases Network, Carlos III Health Institute, Madrid, Spain.
| | - Mariano Motuca
- Department of Psychiatry, School of Medicine at Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Ismael Olmos
- Clinical Pharmacology Unit, Pharmacy Department, Vilardebó Hospital, Administración de Servicios de Salud (ASSE), Montevideo, Uruguay.
| | - Susanna Every-Palmer
- Department of Psychological Medicine, University of Otago Wellington, Wellington, New Zealand.
| | - Ric M Procyshyn
- Department of Psychiatry, University of British Columbia, Vancouver, Canada; British Columbia Mental Health and Substance Use Services Research Institute, Vancouver, Canada.
| | - Christopher Rohde
- Department of Affective Disorders, Aarhus University Hospital - Psychiatry, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Suhas Satish
- Department of Psychiatry, National Institute of Mental Health and Neurosciences [NIMHANS], Bangalore, India
| | - Peter F J Schulte
- Mental Health Services Noord-Holland-Noord, Alkmaar, Netherlands; Dutch Clozapine Collaboration Group, Castricum, Netherlands.
| | - Edoardo Spina
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.
| | - Hiroyoshi Takeuchi
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan.
| | - Hélène Verdoux
- Université Bordeaux, Inserm, Bordeaux Population Health Research Center, Team Pharmacoepidemiology, UMR 1219, F-33000 Bordeaux, France.
| | - Christoph U Correll
- Division of Psychiatry Research, Northwell Health, The Zucker Hillside Hospital, New York, NY, USA; Department of Psychiatry and Molecular Medicine, The Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, New York, NY, USA; Department of Child and Adolescent Psychiatry, Charité Universitätsmedizin, Berlin, Germany.
| | - Jose de Leon
- Mental Health Research Center, Eastern State Hospital, Lexington, KY, USA; Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apóstol Hospital, University of the Basque Country, Vitoria, Spain.
| |
Collapse
|
4
|
Verdoux H, Quiles C, de Leon J. Optimizing co-prescription of clozapine and antiseizure medications: a systematic review and expert recommendations for clinical practice. Expert Opin Drug Metab Toxicol 2024; 20:347-358. [PMID: 38613254 DOI: 10.1080/17425255.2024.2343020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 04/10/2024] [Indexed: 04/14/2024]
Abstract
INTRODUCTION Antiseizure medication (ASM) add-on to clozapine may be efficient to target clozapine-resistant mood or psychotic symptoms or clozapine-related adverse drug reactions (ADR) such as seizures. We aimed to synthesize the information relevant for clinical practice on the risks and benefits of clozapine-ASM co-prescription. AREAS COVERED Articles were identified with MEDLINE, Web of Sciences and PsycINFO search from inception through October 2023. The review was restricted to ASM with mood-stabilizing properties or with potential efficacy for resistant psychotic symptoms (valproate (VPA), lamotrigine, topiramate, carbamazepine, oxcarbazepine). EXPERT OPINION VPA add-on to clozapine is associated with a high risk of serious ADR (myocarditis, neutropenia, pneumonia) mostly explained by complex time-dependent drug-drug interactions. The initial inhibitory effects on clozapine metabolism require slow titration to avoid immuno-allergic reactions. After the titration period, VPA has mainly inductive effects on clozapine metabolism that are more marked in smokers requiring therapeutic drug monitoring. Lamotrigine and topiramate add-on may be recommended as the first-line treatment for clozapine-related seizures, but there is limited evidence regarding the efficacy of this strategy for clozapine-resistant psychotic symptoms. Carbamazepine should not be co-prescribed with clozapine because of its potential for agranulocytosis and for inducing clozapine metabolism.
Collapse
Affiliation(s)
- Hélène Verdoux
- Univ. Bordeaux, Inserm, Bordeaux Population Health Research Center, team pharmacoepidemiology, Bordeaux, France
| | - Clélia Quiles
- Centre Hospitalier Charles Perrens, Bordeaux, France
| | - Jose de Leon
- Mental Health Research Center at Eastern State Hospital, Lexington, USA
- Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apostol Hospital, University of the Basque Country, Vitoria, Spain
| |
Collapse
|
5
|
Besag FMC, Berry D, Vasey MJ, Patsalos PN. Drug-drug interactions between antiseizure medications and antipsychotic medications: a narrative review and expert opinion. Expert Opin Drug Metab Toxicol 2023; 19:829-847. [PMID: 37925741 DOI: 10.1080/17425255.2023.2278676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 10/30/2023] [Indexed: 11/07/2023]
Abstract
INTRODUCTION Antiseizure medications (ASMs) and antipsychotic drugs are frequently coadministered with the potential for drug-drug interactions. Interactions may either be pharmacokinetic or pharmacodynamic, resulting in a decrease or increase in efficacy and/or an increase or decrease in adverse effects. AREAS COVERED The clinical evidence for pharmacokinetic and pharmacodynamic interactions between ASMs and antipsychotics is reviewed based on the results of a literature search in MEDLINE conducted in April 2023. EXPERT OPINION There is now extensive published evidence for the clinical importance of interactions between ASMs and antipsychotics. Enzyme-inducing ASMs can decrease blood concentrations of many of the antipsychotics. There is also evidence that enzyme-inhibiting ASMs can increase antipsychotic blood concentrations. Similarly, there is limited evidence showing that antipsychotic drugs may affect the blood concentrations of ASMs through pharmacokinetic interactions. There is less available evidence for pharmacodynamic interactions, but these can also be important, as can displacement from protein binding. The lack of published evidence for an interaction should not be interpreted as meaning that the given interaction does not occur; the evidence is building continually. There is no substitute for careful patient monitoring and sound clinical judgment.
Collapse
Affiliation(s)
- Frank M C Besag
- Child and Adolescent Mental Health Services (CAMHS), East London NHS Foundation Trust, Bedford, UK
- School of Pharmacy, University College London, London, UK
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Dave Berry
- Toxicology Unit, Kings College Hospital, London, UK
| | - Michael J Vasey
- Child and Adolescent Mental Health Services (CAMHS), East London NHS Foundation Trust, Bedford, UK
| | - Philip N Patsalos
- Department of Clinical and Experimental Epilepsy, University College London Queen Square Institute of Neurology, London, UK
| |
Collapse
|
6
|
Santos RT, Mullen S, Crouse EL, Adams KS. Comparison of clozapine doses and tolerability in patients with and without concurrent valproic acid. Ment Health Clin 2023; 12:336-341. [PMID: 36644583 PMCID: PMC9819135 DOI: 10.9740/mhc.2022.12.336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 09/14/2022] [Indexed: 01/05/2023] Open
Abstract
Introduction Valproic acid (VPA) and its various formulations can be given in conjunction with clozapine for seizure prophylaxis or for augmentation in schizophrenia. There is conflicting literature on how VPA affects clozapine metabolism and the incidence of clozapine-related side effects. The purpose of this study is to compare the effects of VPA when given concurrently with clozapine to patients on clozapine monotherapy. Methods A retrospective medical record review was completed to identify patients admitted to the inpatient psychiatry unit at an academic medical center with an order for clozapine with and without concurrent VPA from August 7, 2010 to August 7, 2020. The primary outcome was the difference in clozapine doses in patients on clozapine as monotherapy versus dual therapy with VPA. Secondary outcomes include the difference in incidence of adverse effects in monotherapy versus dual therapy, as well as clozapine and norclozapine concentrations in both treatment groups. Results During the study period, 73 patients were included in the monotherapy group and 35 patients were included in the dual therapy group. The average clozapine dose in the dual therapy group was 250 mg (95% CI = 194.7, 305.4) which was significantly higher than the average monotherapy dose of 175.9 mg (95% CI = 134.0, 208.7; P = .016). However, there was no significant difference in the average clozapine concentration between the dual therapy group (392.5 ng/mL; 95% CI = 252.8, 532.2) and monotherapy group (365.9 ng/mL; 95% CI = 260.5, 471.3; P = .756). There were higher rates of tachycardia (45.7% vs 17.8%; P = .002), sedation (51.4% vs 8.2%; P < .001), and constipation (42.8% vs 9.5%; P < .001) in the dual therapy group compared to the monotherapy group, respectively. Discussion Patients on concurrent clozapine and VPA received higher doses of clozapine and experienced a higher incidence of tachycardia, sedation, and constipation.
Collapse
Affiliation(s)
- Ranel Troy Santos
- PGY2 Resident, Virginia Commonwealth University Health System, Department of Pharmacy Services, Richmond, Virginia,
| | - Sandra Mullen
- Clinical Pharmacy Specialist, Virginia Commonwealth University Health System, Department of Pharmacy Services, Richmond, Virginia
| | - Ericka L. Crouse
- Associate Professor, Virginia Commonwealth University Health System, Department of Pharmacy Services, Richmond, Virginia
| | - Katie S. Adams
- Clinical Pharmacy Specialist, Virginia Commonwealth University Health System, Department of Pharmacy Services, Richmond, Virginia
| |
Collapse
|
7
|
Effects of Age, Sex, and Comedication on the Plasma Concentrations of Olanzapine in Chinese Patients With Schizophrenia Based on Therapeutic Drug Monitoring Data. J Clin Psychopharmacol 2022; 42:552-559. [PMID: 36286707 DOI: 10.1097/jcp.0000000000001618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Olanzapine (OLA) is an atypical second-generation antipsychotic that exhibits significant pharmacokinetic variability. We retrospectively investigated the effects of age, sex, and specific comedications on OLA pharmacokinetics in Chinese patients with schizophrenia. METHODS Data on sex, age, and OLA dosage and steady-state plasma concentrations of 386 patients with schizophrenia (who have received OLA or a comedication of OLA with a psychotherapeutic drug) were collected and analyzed. The combined effects of dosage, age, sex, and comedication on OLA plasma levels were assessed via multiple linear regression analyses. RESULTS A daily dose of OLA was positively correlated with the drug's plasma concentrations. Overall, the OLA plasma concentrations and concentration-to-dose ratio (C/D) of the studied patients varied by 53.6- and 64.1-fold, achieving median values of 42.7 ng/mL and 2.73 (ng/mL)/(mg/d), respectively. Furthermore, a 1.27-fold higher estimated C/D in patients 60 years or older than in those younger than 60 years was identified. Female patients demonstrated a 33.6% higher C/D than in male patients. When coadministered with mood stabilizers (valproate or lithium), the median OLA C/D was 24.1% to 26.1% lower than that of OLA monotherapy. Interestingly, the OLA plasma concentration and C/D were not significantly affected by a comedication with aripiprazole, haloperidol, amisulpride, risperidone, clozapine, ziprasidone, citalopram, or buspirone. CONCLUSIONS The administered drug's dose was identified as an important determinant of the achieved OLA plasma concentration, with a positive correlation. The patients' sex and valproate (or lithium) comedication can significantly affect the C/D of OLA. Therapeutic drug monitoring should be routinely applied in cases of OLA-receiving patients with schizophrenia.
Collapse
|
8
|
Gao P, Wang J, Zhang L, Wang H, Hu Y, Ni Y, Huang L, Zhu Z, Luo F. The impact of ibuprofen on valproic acid plasma concentration in pediatric patients. Xenobiotica 2022; 52:535-540. [PMID: 35997547 DOI: 10.1080/00498254.2022.2117109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
The combination of valproic acid (VPA) and ibuprofen is common in children with epilepsy. Three case reports investigated that ibuprofen might decrease plasma concentration of VPA, however, no cohort study was published to evaluate the interaction of ibuprofen on VPA plasma concentration in pediatric patients.Data from patients with measured VPA trough concentrations (C0) were retrospectively collected in a Chinese teaching and tertiary Children's Hospital from January 2017 to June 2019. The samples measured within 6 weeks of the last ibuprofen administration were considered as ibuprofen combination samples. Patients with paired samples before and after ibuprofen administration were additionally analyzed. The effects of ibuprofen on the VPA trough concentration to dose (C0/D) ratio were investigated. The proportion of samples with achieved target concentrations of VPA (50-100 mg/L) and the corresponding required dosage were compared. Moreover, subgroup analysis according to the interval between the last ibuprofen dosage and C0 measurement was performed.A total of 616 samples from 434 patients, of whom 16 had paired samples, were included. VPA C0/D decreased when ibuprofen was administered by 7.5% and 30.6% of the total samples and paired samples, respectively. The interaction was significant within 1 week of the last ibuprofen dose. No significant differences were observed in the proportion of target concentration achieved and VPA dose requirement when ibuprofen was combined.A moderate effect of ibuprofen on VPA C0/D was observed within 1 week of ibuprofen administration; the target concentration and required doses of VPA were comparable.
Collapse
Affiliation(s)
- Peng Gao
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Junyan Wang
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Liwen Zhang
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Huijuan Wang
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yan Hu
- Department of Pharmacy, The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, China
| | - Yinghua Ni
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Lingfei Huang
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Zhengyi Zhu
- Department of Pharmacy, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Fang Luo
- Department of Pharmacy, The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, China.,Zhejiang Key Laboratory of Prevention, Diagnosis and Therapy of Upper Gastrointestinal Cancer, Zhejiang Cancer Hospital, Hangzhou 310022, China
| |
Collapse
|
9
|
Diaz FJ, Zhang X, Pantazis N, De Leon J. Measuring Individual Benefits of Medical Treatments Using Longitudinal Hospital Data with Non-Ignorable Missing Responses Caused by Patient Discharge: Application to the Study of Benefits of Pain Management Post Spinal Fusion. REVISTA COLOMBIANA DE ESTADÍSTICA 2022. [DOI: 10.15446/rce.v45n2.101597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Electronic health records (EHR) provide valuable resources for longitudinal studies and understanding risk factors associated with poor clinical outcomes. However, they may not contain complete follow-ups, and the missing data may not be at random since hospital discharge may depend in part on expected but unrecorded clinical outcomes that occur after patient discharge. These non-ignorable missing data requires appropriate analysis methods. Here, we are interested in measuring and analyzing individual treatment benefits of medical treatments in patients recorded in EHR databases. We present a method for predicting individual benefits that handles non-ignorable missingness due to hospital discharge. The longitudinal clinical outcome of interest is modeled simultaneously with the hospital length of stay using a joint mixed-effects model, and individual benefits are predicted through a frequentist approach: the empirical Bayesian approach. We illustrate our approach by assessing individual pain management benefits to patients who underwent spinal fusion surgery. By calculating sample percentiles of empirical Bayes predictors of individual benefits, we examine the evolution of individual benefits over time. We additionally compare these percentiles with percentiles calculated with a Monte Carlo approach. We showed that empirical Bayes predictors of individual benefits do not only allow examining benefits in specific patients but also reflect overall population trends reliably.
Collapse
|
10
|
Zang YN, Guo W, Dong F, Li AN, de Leon J, Ruan CJ. Published population pharmacokinetic models of valproic acid in adult patients: a systematic review and external validation in a Chinese sample of inpatients with bipolar disorder. Expert Rev Clin Pharmacol 2022; 15:621-635. [PMID: 35536685 DOI: 10.1080/17512433.2022.2075849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND This study reviewed all published valproic acid (VPA) population pharmacokinetic (PPK) models in adult patients and assessed them using external validation methods to determine predictive performance. METHODS Thirteen published PPK models (labeled with letters A to M) not restricted to children were identified in PubMed, Embase, and Web of Science databases. They were evaluated in a sample totaling 411 serum concentrations from 146 adult inpatients diagnosed with bipolar disorder in a Chinese hospital. Serum concentrations of VPA were analyzed by validated ultra-performance liquid chromatography-tandem mass spectrometry. Performance was assessed by 4 tests (prediction-based diagnostics, visual predictive checks, normalized prediction distribution error, and Bayesian forecasting). RESULTS Models K and L, developed in large samples of Chinese and Thai patients, showed good performance in our Chinese dataset. Models H and J demonstrated good performance in Tests 2 and 3 of the 4 tests, respectively. Another 7 models exhibited intermediate performance. The models with the worst performance, F and M, could not be improved by Bayesian forecasting. CONCLUSION In our validation study the most important factors contributing to good performance were absence of children, Asian ethnicity, one-compartment models and inclusion of body weight and VPA dose in previously published models.
Collapse
Affiliation(s)
- Yan-Nan Zang
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Wei Guo
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Fang Dong
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - An-Ning Li
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Jose de Leon
- Mental Health Research Center at Eastern State Hospital, 1350 Bull Lea Road, Lexington, KY 40511, USA.,Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apóstol Hospital, University of the Basque Country, Vitoria, Spain
| | - Can-Jun Ruan
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| |
Collapse
|
11
|
Sangüesa E, Cirujeda C, Concha J, Padilla PP, García CB, Ribate MP. Exploring the usefulness of plasma level determination and pharmacogenetics for patients treated with clozapine. Per Med 2022; 19:181-192. [PMID: 35259926 DOI: 10.2217/pme-2021-0029] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Aims: The aims of the present study were to assess the variance of plasma clozapine (CLZ) levels and to identify the influence of sociodemographic and pharmacogenetic factors on it and to introduce these tools in a clinical setting. Patients & methods: CLZ concentration was measured and genetic variants of CLZ pharmacokinetic and pharmacodynamic factors were assessed in 23 patients with psychotic disorders. Results: A significant association between mean concentration/dose ratio (C/D) and smoking status, age and weight were found. There was a significant difference in mean plasma CLZ levels and gender. The rs762551 AA genotype in smokers had a significantly lower C/D. Conclusion: In addition to classical factors, monitoring of plasma concentrations together with pharmacogenetics led to greater individualization of treatment.
Collapse
Affiliation(s)
- Estela Sangüesa
- Pharmacy degree, Faculty of Health Sciences, Universidad San Jorge, Villanueva de Gállego, Zaragoza, Spain
| | - Christine Cirujeda
- Centro Neuropsiquiátrico Nuestra Señora del Carmen. Hermanas Hospitalarias, Zaragoza, Spain
| | - Julia Concha
- Pharmacy degree, Faculty of Health Sciences, Universidad San Jorge, Villanueva de Gállego, Zaragoza, Spain
| | - Pedro Pablo Padilla
- Centro Neuropsiquiátrico Nuestra Señora del Carmen. Hermanas Hospitalarias, Zaragoza, Spain
| | - Cristina Belén García
- Pharmacy degree, Faculty of Health Sciences, Universidad San Jorge, Villanueva de Gállego, Zaragoza, Spain
| | - María Pilar Ribate
- Pharmacy degree, Faculty of Health Sciences, Universidad San Jorge, Villanueva de Gállego, Zaragoza, Spain
| |
Collapse
|
12
|
Abstract
BACKGROUND Valproic acid (VPA) is frequently used with clozapine (CLZ) as mood stabilizer and/or seizure prophylaxis. Valproic acid is known to reduce N-desmethylclozapine (N-DMC) but not CLZ levels. This leads to the hypothesis that VPA induces the CLZ metabolism via non-N-desmethylation pathways. Therefore, we aimed to investigate the effect of concurrent VPA use on the serum concentrations of a spectrum of CLZ metabolites in patients, adjusting for smoking. METHODS In total, 288 patients with an overall number of 737 serum concentration measurements of CLZ and metabolites concurrently using VPA (cases, n = 22) or no interacting drugs (controls, n = 266) were included from a routine therapeutic drug monitoring service. Linear mixed model analyses were performed to compare the dose-adjusted concentrations (C/D) of CLZ, N-DMC, CLZ 5N/N+-glucuronides, and metabolite-to-parent ratios in cases versus controls. RESULTS After adjusting for covariates, the N-DMC (-40%, P < 0.001) and N+-glucuronide C/Ds (-78%, P < 0.001) were reduced in cases versus controls, while the CLZ C/D was unchanged (P > 0.7). In contrast, the 5N-glucuronide C/D (+250%, P < 0.001) and 5N-glucuronide-to-CLZ ratios (+120%, P = 0.01) were increased in cases versus controls. CONCLUSIONS Our findings show that complex changes in CLZ metabolism underly the pharmacokinetic interaction with VPA. The lower levels of N-DMC seem to be caused by VPA-mediated induction of CLZ 5N-glucuronide formation, subsequently leading to reduced substrate availability for N-desmethylation. Whether the changes in CLZ metabolism caused by VPA affects the clinical outcome warrants further investigation.
Collapse
|
13
|
Pardiñas AF, Owen MJ, Walters JTR. Pharmacogenomics: A road ahead for precision medicine in psychiatry. Neuron 2021; 109:3914-3929. [PMID: 34619094 DOI: 10.1016/j.neuron.2021.09.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 08/05/2021] [Accepted: 09/09/2021] [Indexed: 12/11/2022]
Abstract
Psychiatric genomics is providing insights into the nature of psychiatric conditions that in time should identify new drug targets and improve patient care. Less attention has been paid to psychiatric pharmacogenomics research, despite its potential to deliver more rapid change in clinical practice and patient outcomes. The pharmacogenomics of treatment response encapsulates both pharmacokinetic ("what the body does to a drug") and pharmacodynamic ("what the drug does to the body") effects. Despite early optimism and substantial research in both these areas, they have to date made little impact on clinical management in psychiatry. A number of bottlenecks have hampered progress, including a lack of large-scale replication studies, inconsistencies in defining valid treatment outcomes across experiments, a failure to routinely incorporate adverse drug reactions and serum metabolite monitoring in study designs, and inadequate investment in the longitudinal data collections required to demonstrate clinical utility. Nonetheless, advances in genomics and health informatics present distinct opportunities for psychiatric pharmacogenomics to enter a new and productive phase of research discovery and translation.
Collapse
Affiliation(s)
- Antonio F Pardiñas
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
| | - Michael J Owen
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK.
| | - James T R Walters
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
| |
Collapse
|
14
|
Bennett S, Shad MU. Valproic acid autoinduction: a case-based review. Int J Bipolar Disord 2021; 9:27. [PMID: 34468892 PMCID: PMC8408294 DOI: 10.1186/s40345-021-00232-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/29/2021] [Indexed: 11/10/2022] Open
Abstract
Although valproic acid (VPA) induces the metabolism of multiple other drugs, the clinical reports of VPA autoinduction are rare. A comprehensive literature search yielded only one published case series, which provided the rationale to conduct a review of the published cases along with a new case of VPA autoinduction. Although there may be myriad of reasons for lack of published cases of VPA autoinduction, potential underreporting may be one of the core reasons. Lack of understanding into the highly complex metabolism of VPA may also make it difficult to recognize and report VPA autoinduction. However, it is important to mention that in addition to autoinduction increased elimination of VPA may be mediated by several pharmacokinetic (PK) factors, such as drug interactions, genetic polymorphisms of metabolic enzymes, and protein displacement reactions. As VPA is metabolized by multiple metabolic pathways, the risk for drug interactions is relatively high. There is also a growing evidence for high genetic inducibility of some enzymes involved in VPA metabolism. Protein displacement reactions with VPA increase the biologically active and readily metabolizable free fraction and pose a diagnostic challenge as they are usually not requested by most clinicians. Thus, monitoring of free fraction with total VPA levels may prevent clinically serious outcomes and optimize VPA treatment in clinically challenging patients. This case-based review compares the clinical data from three published cases and a new case of VPA autoinduction to enhance clinicians' awareness of this relatively rare but clinically relevant phenomenon along with a discussion of potential underlying mechanisms.
Collapse
Affiliation(s)
| | - Mujeeb U Shad
- University of Nevada Las Vegas, Las Vegas, NV, USA. .,Touro University Nevada, Las Vegas, NV, USA. .,Valley Health System, Las Vegas, NV, USA.
| |
Collapse
|
15
|
Valproate for schizophrenia: ambrosia? CNS Spectr 2021; 26:314-315. [PMID: 32241333 DOI: 10.1017/s1092852920001285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
16
|
Considerations of HLA, Renal Failure, Valproic Acid Use, and Current Treatment Guidelines in Clozapine-Induced Agranulocytosis. Case Rep Psychiatry 2021; 2021:8816390. [PMID: 33688445 PMCID: PMC7914079 DOI: 10.1155/2021/8816390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 01/15/2021] [Accepted: 02/04/2021] [Indexed: 11/26/2022] Open
Abstract
Clozapine, the choice atypical antipsychotic for refractory schizophrenia, schizoaffective disorder, and bipolar disorder, has been shown to reduce positive and negative symptoms of schizophrenia. Clozapine, though beneficial in reducing the need for hospitalization, rehabilitation, and health care costs, is known as a drug of last resort due to its potential adverse event of clozapine-induced agranulocytosis, which holds a case fatality rate between 4.2 and 16%. Herein, we describe a female patient with longstanding schizoaffective disorder and chronic kidney disease who suffered from clozapine-induced agranulocytosis after failing two other atypical antipsychotics. Retrospective considerations of this case and management highlight risk factors such as HLA status, renal failure, and concurrent valproic acid use which presently do not have official screening, guidelines, or restrictions in place when prescribing clozapine. Additionally, there are no specific clozapine-induced agranulocytosis management recommendations such as G-CSF/filgrastim dose, timing of bone marrow aspirate and biopsy, and use of concomitant valproate. We propose that further comprehensive official screening, monitoring, and guidelines in the prescribing of clozapine, and further guidelines in the treatment of clozapine induced agranulocytosis, could increase the cost-effectiveness of clozapine treatment, and decrease the incidence, and morbidity of this feared adverse event.
Collapse
|
17
|
The Impact of Smoking, Sex, Infection, and Comedication Administration on Oral Olanzapine: A Population Pharmacokinetic Model in Chinese Psychiatric Patients. Eur J Drug Metab Pharmacokinet 2021; 46:353-371. [PMID: 33677821 DOI: 10.1007/s13318-021-00673-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND OBJECTIVE: Prior olanzapine population pharmacokinetic (PPK) models have focused on the effects of sex and smoking on olanzapine clearance. This PPK model in Chinese adult psychiatric patients also investigated the influence of comedications and co-occurrence of infections on olanzapine clearance, and explored how to personalize oral olanzapine dosage in the clinical setting. METHODS A total of 1546 serum concentrations from 354 patients were collected in this study. A one-compartment model with first-order absorption was employed to develop the PPK model using a nonlinear mixed-effects modeling approach. Covariates included demographic parameters, co-occurrence of infection and concomitant medications (including dangguilonghui tablets, a Chinese herbal medicine for constipation). Bootstrap validation (1000 runs) and external validation of 50 patients were employed to evaluate the final model. Simulations were performed to explore the personalization of olanzapine dosing after stratification by sex, smoking, and comedication with valproate. RESULTS Typical estimates for the absorption rate constant (Ka), apparent clearance (CL/F), and apparent distribution volume (V/F) were 0.30 h-1, 12.88 L/h, and 754.41 L, respectively. Olanzapine clearance was increased by the following variables: 1.23-fold by male sex, 1.23-fold by smoking, 1.23-fold by comedication with valproate, 1.16-fold by sertraline, and 2.01-fold by dangguilonghui tablets. Olanzapine clearance was decreased by the following variables: 0.75-fold by co-occurrence of infection, 0.70-fold by fluvoxamine, and 0.78-fold by perphenazine. The model evaluation indicated that the final model's performance was good, stable, and precise. CONCLUSION This study contributes to the personalization of oral olanzapine dosing, but further studies should be performed to verify the effects of infection and comedications, including valproate and dangguilonghui.
Collapse
|
18
|
Future Studies on the Interaction Between Clozapine and Valproic Acid Should Aspire to Include Longitudinal Designs and Free Valproate Concentrations, and Should Consider that Inducer and/or Inhibitory Effects May Vary With Time, the Individual, and the Auto-Induction of Valproic Acid. Ther Drug Monit 2020; 42:159-161. [PMID: 31633608 DOI: 10.1097/ftd.0000000000000705] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
19
|
Zhang X, de Leon J, Crespo-Facorro B, Diaz FJ. Measuring individual benefits of psychiatric treatment using longitudinal binary outcomes: Application to antipsychotic benefits in non-cannabis and cannabis users. J Biopharm Stat 2020; 30:916-940. [DOI: 10.1080/10543406.2020.1765371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Xuan Zhang
- Department of Biostatistics, The University of Kansas Medical Center, Kansas City, KS, United States
- Boston Strategic Partners, Inc, Boston, MA, United States
| | - Jose de Leon
- Mental Health Research Center at Eastern State Hospital, Lexington, KY, United States
| | - Benedicto Crespo-Facorro
- University Hospital Virgen Del Rocío, Seville, Spain
- CIBERSAM G26-IBiS, University of Seville, Seville, Spain
- Department of Psychiatry, Marqués De Valdecilla University Hospital, IDIVAL, Santander, Spain
- School of Medicine, University of Cantabria, Santander, Spain
| | - Francisco J. Diaz
- Department of Biostatistics, The University of Kansas Medical Center, Kansas City, KS, United States
| |
Collapse
|
20
|
de Leon J, Schoretsanitis G, Kane JM, Ruan CJ. Using therapeutic drug monitoring to personalize clozapine dosing in Asians. Asia Pac Psychiatry 2020; 12:e12384. [PMID: 32119764 DOI: 10.1111/appy.12384] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 01/19/2020] [Accepted: 02/10/2020] [Indexed: 12/27/2022]
Abstract
This narrative review on clozapine blood levels or therapeutic drug monitoring (TDM) includes sections focused on drug clearance and TDM, personalized dosing with TDM, clinical applications of TDM in Asians, and areas needing further study. Asian patients need half the clozapine dose (D) used in the United States to get the same blood concentrations (C). The concentration-to-dose (C/D) ratio measures drug clearance. In the United States, the average clozapine patient usually needs from 300 to 600 mg/day to reach 350 ng/mL. US male smokers reach this therapeutic C with a D of 600 mg/day (C/D ratio of 0.60 = 600/350), whereas US female nonsmokers usually need a D of 300 mg/day (C/D ratio of 1.17 = 300/350). While in the United States, average CLO C/D ratios typically are 0.6-1.2 ng/mL per mg/day, in Asian populations they range from 1.20 in male smokers to 2.40 in female smokers, requiring Ds of 300 to 150 mg/day to obtain 350 ng/mL. Asian patients can become clozapine poor metabolizers (PMs), needing very low Ds (50-150 mg/day) to get therapeutic Cs, by taking inhibitors (fluvoxamine, oral contraceptives and valproic acid), due to obesity, or during inflammations with systemic effects. In 573 Asian patients from five samples, around 1% were PMs due to taking inhibitors, 1% due to inflammation, 1% due to obesity, and 7% were potential genetic PMs. The potential genetic PMs ranged between 3% and 13%, but this prevalence will have to be better established in future studies including genetic testing for possible CYP1A2 mutations, which may explain PM status.
Collapse
Affiliation(s)
- Jose de Leon
- Mental Health Research Center, Eastern State Hospital, Lexington, Kentucky.,Psychiatry and Neurosciences Research Group (CTS-549), Institute of Neurosciences, University of Granada, Granada, Spain.,Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apóstol Hospital, University of the Basque Country, Vitoria, Spain
| | - Georgios Schoretsanitis
- Department of Psychiatry Research, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York
| | - John M Kane
- Department of Psychiatry Research, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York.,Department of Psychiatry and Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York
| | - Can-Jun Ruan
- Laboratory of Clinical Psychopharmacology & The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
21
|
Reduction in N-Desmethylclozapine Level Is Determined by Daily Dose But Not Serum Concentration of Valproic Acid-Indications of a Presystemic Interaction Mechanism. Ther Drug Monit 2020; 41:503-508. [PMID: 31259880 DOI: 10.1097/ftd.0000000000000619] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Valproic acid (VPA) is frequently used together with clozapine (CLZ) as mood-stabilizer or for the prevention of seizures in patients with psychotic disorders. VPA is known to reduce levels of the pharmacologically active CLZ-metabolite N-desmethylclozapine (N-DMC), but factors determining the degree of this interaction are unknown. Here, we investigated the relationship between VPA dose and serum concentration on N-DMC levels in a large patient population adjusting for sex, age, and smoking habits as covariates. METHODS A total of 763 patients with steady-state serum concentrations of CLZ and N-DMC concurrently using VPA (cases, n = 76) or no interacting drugs (controls, n = 687) were retrospectively included from a therapeutic drug monitoring service at Diakonhjemmet Hospital, Oslo, between March 2005 and December 2016. In addition to information about prescribed doses, age, sex, smoking habits, and use of other interacting drugs were obtained. The effects of VPA dose and serum concentration on dose-adjusted N-DMC levels were evaluated by univariate correlation and multivariate linear mixed-model analyses adjusting for covariates. RESULTS The dose-adjusted N-DMC levels were approximately 38% lower in VPA users (cases) versus nonusers (controls) (P < 0.001). Within the VPA cases, a negatively correlation between VPA dose and dose-adjusted N-DMC levels was observed with an estimated reduction of 1.42% per 100-mg VPA dose (P = 0.033) after adjusting for sex, age, and smoking. By contrast, there was no correlation between VPA serum concentration and dose-adjusted N-DMC levels (P = 0.873). CONCLUSIONS The study shows that VPA dose, not concentration, is of relevance for the degree of reduction in N-DMC level in clozapine-treated patients. Presystemic induction of UGT enzymes or efflux transporters might underlie the reduction in N-DMC level during concurrent use of VPA. Our findings indicate that a VPA daily dose of 1500 mg or higher provides a further 21% reduction in N-DMC concentration. This is likely a relevant change in the exposure of this active metabolite where low levels are associated with implications of CLZ therapy.
Collapse
|
22
|
Schmitz A, Botner B, Hund M. Bupropion With Clozapine: Case Reports of Seizure After Coadministration. J Pharm Pract 2020; 34:497-502. [PMID: 32079452 DOI: 10.1177/0897190020904280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Clozapine is more effective than other atypical antipsychotics for treatment resistant schizophrenia, but has serious side effects. Clozapine has an estimated cumulative seizure risk of 10% in patients treated for 3.8 years. Bupropion can also induce seizures and its estimated risk is 0.4% at recommended doses. While some risk factors for seizures are known, much remains unknown about predicting seizure risk. Cases: We present 2 cases of seizures in patients treated with clozapine and bupropion without a seizure history. In the first case, a patient with schizoaffective disorder treated with dual antipsychotic therapy had a witnessed generalized tonic-clonic seizure. With the exception of bupropion/naltrexone which was started 2.5 months prior for weight loss, she had not had any recent medication changes. In the second case, a patient with schizoaffective disorder was treated with clozapine and was prescribed bupropion SR for smoking cessation for an extended duration. He had cut back on cigarette use in the 2 months prior to reporting "spells." The neurologist's assessment was probable epileptic seizures which resolved after the bupropion was stopped and divalproex was started for seizure prophylaxis. CONCLUSION Clozapine and bupropion are known to lower the seizure threshold, but little information is available regarding the risk when used in combination. It is unclear whether these agents, when used in combination, have additive seizure risk or possible synergistic effects. Bupropion should be used cautiously in patients treated with clozapine. Safer agents that do not lower the seizure threshold should be utilized whenever possible.
Collapse
Affiliation(s)
- Allison Schmitz
- Pharmacy Department, 20057Fargo VA Health Care System, ND, USA
| | - Brandon Botner
- Pharmacy Department, 20057Fargo VA Health Care System, ND, USA
| | - Morris Hund
- Mental Health Department, 20057Fargo VA Health Care System, ND, USA
| |
Collapse
|
23
|
de Leon J, Rajkumar AP, Kaithi AR, Schoretsanitis G, Kane JM, Wang CY, Tang YL, Lin SK, Hong KS, Farooq S, Ng CH, Ruan CJ, Andrade C. Do Asian Patients Require Only Half of the Clozapine Dose Prescribed for Caucasians? A Critical Overview. Indian J Psychol Med 2020; 42:4-10. [PMID: 31997860 PMCID: PMC6970303 DOI: 10.4103/ijpsym.ijpsym_379_19] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 09/24/2019] [Accepted: 10/07/2019] [Indexed: 12/12/2022] Open
Abstract
Since 1997, studies have found that Asians need lower clozapine doses than Caucasians. Caucasians with average clozapine metabolism may need from 300 to 600 mg/day to reach the therapeutic range (350 ng/ml). Thus, serum clozapine concentration-to-dose (C/D) ratios typically range between 0.60 (male smokers) and 1.20 (female non-smokers). A 2019 systematic review of clozapine levels demonstrated weighted mean C/D ratios of 1.57 in 876 East Asians and 1.07 in 1147 Caucasians (P < .001). In Asian countries, average clozapine doses are lower than 300 mg/day. After sex and smoking stratification in 5 Asian samples with clozapine concentrations, the clozapine dose required to reach 350 ng/ml in female non-smokers ranged from 145 to 189 mg/day and in male smokers, from 259 to 294 mg/day. Thus, in Asian patients with average metabolism (with no inducers other than smoking, with no inhibitors, and in the absence of extreme obesity), the dose needed for clinical response may range between 150 mg/day for female non-smokers to 300 mg/day for male smokers. Clozapine levels may help personalize dosing in clozapine poor metabolizers (PMs) and ultrarapid metabolizers (UMs). Asian PMs may need very low doses (50-150 mg/day) to obtain therapeutic concentrations. About 10% (range 2-13%) of Asians are genetic PM cases. Other PMs are patients taking CYP1A2 inhibitors such as fluvoxamine, oral contraceptives, and valproate. Temporary clozapine PM status may occur during severe systemic infections/inflammations with fever and C-reactive protein (CRP) elevations. Asian UMs include patients taking potent inducers such as phenytoin, and rarely, valproate.
Collapse
Affiliation(s)
- Jose de Leon
- Mental Health Research Center, Eastern State Hospital, Lexington, Kentucky, USA.,Psychiatry and Neurosciences Research Group (CTS-549), Institute of Neurosciences, University of Granada, Granada, Spain, and Biomedical Research Centre in Mental Health Net (CIBERSAM), Santiago Apóstol Hospital, University of the Basque Country, Vitoria, Spain
| | - Anto P Rajkumar
- Department of Psychiatry, Christian Medical College, Vellore, Tamil Nadu, India.,Institute of Mental Health, University of Nottingham, Nottingham, United Kingdom
| | | | - Georgios Schoretsanitis
- Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York, USA
| | - John M Kane
- Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York, USA.,Department of Psychiatry and Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
| | - Chuan-Yue Wang
- Department of Psychiatry, The National Clinical Research Centre for Mental Disorders and Beijing Key Lab of Mental Disorders and Beijing Institute for Brain Disorders Center of Schizophrenia, Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Yi-Lang Tang
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia, and Substance Abuse Treatment Program, Atlanta VA Medical Center, Decatur, Georgia, USA
| | - Shih-Ku Lin
- Department of General Psychiatry, Taipei City, Psychiatric Center, Taipei, Taiwan, and Department of Psychiatry, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Kyung Sue Hong
- Department of Psychiatry, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea
| | - Saeed Farooq
- School of Primary, Community and Social Care, Faulty of Medicine and Health Sciences, Keele University, Staffordshire, and Midlands Partnership NHS Foundation Trust, Staffordshire, United Kingdom
| | - Chee H Ng
- Department of Psychiatry, The Melbourne Clinic and St Vincent's Hospital, The University of Melbourne, Melbourne, Victoria, Australia
| | - Can-Jun Ruan
- Laboratory of Clinical Psychopharmacology & The National Clinical Research Centre for Mental Disorders & Beijing Key Lab of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Chittaranjan Andrade
- Department of Psychopharmacology, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
| |
Collapse
|
24
|
Lesche D, Mostafa S, Everall I, Pantelis C, Bousman CA. Impact of CYP1A2, CYP2C19, and CYP2D6 genotype- and phenoconversion-predicted enzyme activity on clozapine exposure and symptom severity. THE PHARMACOGENOMICS JOURNAL 2019; 20:192-201. [PMID: 31616047 DOI: 10.1038/s41397-019-0108-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 09/09/2019] [Accepted: 10/02/2019] [Indexed: 12/14/2022]
Abstract
Clozapine is an atypical antipsychotic metabolized by CYP1A2, CYP2D6, and CYP2C19 enzymes. Among 66 adult schizophrenia patients treated with clozapine-based combination therapies, we explored the impact of genotype-predicted CYP1A2, CYP2D6, and CYP2C19 activity on dose-adjusted clozapine concentrations and symptom severity, with and without correction for inhibitors and inducers of these enzymes. Uncorrected activity scores were not associated with dose-adjusted clozapine concentrations or symptom severity. CYP1A2 and CYP2D6 activity scores corrected for known inducers (i.e., smoking) and inhibitors (e.g., concomitant medications) were associated with dose-adjusted clozapine levels and in the case of CYP1A2, symptom severity. However, smoking status and certain inhibitors of clozapine metabolism (i.e., esomeprazole) explained significantly more variance in dose-adjusted clozapine levels relative to corrected activity scores. These findings highlight the clinical importance of nongenetic factors (smoking, concomitant medications) and suggest that the added utility of CYP1A2, CYP2D6, and CYP2C19 activity scores to guide clozapine dosing is currently limited.
Collapse
Affiliation(s)
- Dorothea Lesche
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne & Melbourne Health, Melbourne, VIC, Australia
| | - Sam Mostafa
- myDNA Life Australia Limited, South Yarra, VIC, Australia.,Centre for Medicine Use and Safety, Monash University, Parkville, VIC, Australia
| | - Ian Everall
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne & Melbourne Health, Melbourne, VIC, Australia.,Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.,The Cooperative Research Centre (CRC) for Mental Health, VIC, Australia
| | - Christos Pantelis
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne & Melbourne Health, Melbourne, VIC, Australia.,Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.,The Cooperative Research Centre (CRC) for Mental Health, VIC, Australia
| | - Chad A Bousman
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne & Melbourne Health, Melbourne, VIC, Australia. .,The Cooperative Research Centre (CRC) for Mental Health, VIC, Australia. .,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. .,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. .,Departments of Medical Genetics, Psychiatry, and Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada.
| |
Collapse
|
25
|
Tseng AL, Wong AY, McLelland CJ, Walmsley SL. Drug interactions are not always predictable: the curious case of valproic acid and dolutegravir and a possible explanation. AIDS 2019; 33:1677-1679. [PMID: 31305336 DOI: 10.1097/qad.0000000000002256] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
26
|
Association between electroencephalogram changes and plasma clozapine levels in clozapine-treated patients. Int Clin Psychopharmacol 2019; 34:131-137. [PMID: 30855515 DOI: 10.1097/yic.0000000000000255] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This retrospective observational study was performed to investigate electroencephalogram abnormalities in clozapine-treated patients with refractory schizophrenia or bipolar disorder. The electroencephalogram and plasma clozapine and norclozapine levels in 71 patients were measured on the same day. Fifty-nine patients (85.9%) had a diagnosis of schizophrenia, and 12 patients (14.1%) had a diagnosis of bipolar disorder. The mean daily clozapine dose was 242.9 ± 105.5 mg (range 25-500 mg), and the mean plasma clozapine and norclozapine levels were 429.4 ± 264.1 and 197.8 ± 132.6 ng/ml, respectively. Twenty-five patients (35.2%) were taking valproate in combination with clozapine. electroencephalogram abnormalities were found in 51 (71.8%) patients. No patient reported clinical seizures. Plasma clozapine level was significantly associated with electroencephalogram abnormalities and was identified as a significant predictor of electroencephalogram abnormalities in a logistic regression analysis. The plasma norclozapine levels of patients taking both clozapine and valproic acid were significantly lower than those of patients treated with clozapine alone. These results demonstrate that electroencephalogram abnormalities are closely correlated with plasma clozapine levels. Valproate reduced plasma norclozapine levels. Simultaneous monitoring of electroencephalogram and plasma clozapine levels was useful for adjusting clozapine doses, improving clinical efficacy, and preventing the side effects of clozapine treatment.
Collapse
|
27
|
Wang W, Bai M, Jiang T, Li C, Li P, Zhou H, Wang Z, Li L, Jiang H. Clozapine-induced reduction of l-carnitine reabsorption via inhibition/down-regulation of renal carnitine/organic cation transporter 2 contributes to liver lipid metabolic disorder in mice. Toxicol Appl Pharmacol 2019; 363:47-56. [DOI: 10.1016/j.taap.2018.11.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 11/14/2018] [Accepted: 11/18/2018] [Indexed: 12/30/2022]
|
28
|
Reznik R, Chen RYY, Stanford P. Clozapine toxicity in a CYP2D6 poor metaboliser: Additive effects of haloperidol and valproate on clozapine metabolism. Australas Psychiatry 2018; 26:608-611. [PMID: 29737183 DOI: 10.1177/1039856218771509] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE: To illustrate the complexities of clozapine metabolism with the use of therapeutic drug monitoring. METHODS: We describe a case of clozapine toxicity in a patient with schizophrenia treated with the combination of clozapine, valproate and haloperidol. RESULTS: A 24-year-old CYP2D6 poor metaboliser developed clozapine toxicity corresponding to the additive effects of haloperidol, and increasing clozapine and valproate doses. Saturation of metabolism, evidenced by a high clozapine/norclozapine ratio, was present at this time. CONCLUSIONS: Clozapine metabolism is complex and influenced by multiple factors, including interactions with hepatic P450 enzyme inducers/inhibitors, genetic polymorphisms and the potential for saturation of the N-demethylation metabolic pathway.
Collapse
Affiliation(s)
- Robert Reznik
- VMO Consultant Psychiatrist, Long Bay Hospital, Matraville, NSW, Australia
| | | | - Phoebe Stanford
- Clinical Chemistry Registrar, NSW Health Pathology, The Prince of Wales Hospital, Randwick, NSW, Australia
| |
Collapse
|
29
|
The Effect of Body Weight Changes on Total Plasma Clozapine Concentrations Determined by Applying a Statistical Model to the Data From a Double-Blind Trial. J Clin Psychopharmacol 2018; 38:442-446. [PMID: 30106876 PMCID: PMC6113094 DOI: 10.1097/jcp.0000000000000926] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE/BACKGROUND Some therapeutic drug monitoring studies suggest that increased weight is associated with small increases in clozapine concentrations. The goal of this study was to reanalyze a US double-blind study using a sophisticated statistical model to test whether weight gains from baseline or increases in percentage of body fat from baseline, computed from a published equation, are associated with increased total plasma clozapine concentrations after controlling for the effects of smoking and sex. METHODS/PROCEDURES Using data from a multidosage randomized double-blind US clozapine trial previously published, a random intercept linear model of steady-state total plasma clozapine concentrations was fitted to 424 concentrations from 47 patients. FINDINGS/RESULTS After adjusting for sex and smoking, (1) a 1-kg gain in body weight during clozapine treatment was significantly associated with a 1.4% increase in total plasma clozapine concentrations (95% confidence interval = 0.55 to 2.3) and (2) a 1-point increase in percentage of body fat during clozapine treatment was significantly associated with a 5.4% increase in total clozapine concentration (2.5 to 8.3) in females and 1.4% (-1.1 to 4.0) in males. IMPLICATIONS/CONCLUSIONS As hypothesized, weight increases during clozapine treatment, which probably reflect increases in fat tissue, were associated with increases in total plasma concentrations. Pending further replication in other samples, it seems likely that clozapine may deposit in body fat and that this may decrease clozapine clearance. This change may be small in most patients but may be clinically relevant in females with major gains in body fat.
Collapse
|
30
|
Effect of Valproate and Antidepressant Drugs on Clozapine Metabolism in Patients With Psychotic Mood Disorders. Ther Drug Monit 2018; 40:443-451. [DOI: 10.1097/ftd.0000000000000513] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
31
|
Abstract
OBJECTIVES Valproic acid and clozapine are drugs commonly used in the treatment of schizophrenic and schizoaffective disorders. Pharmacokinetic interactions of valproic acid with several drugs are well known, yet results concerning the interaction with clozapine are inconsistent. METHODS Steady-state dose-corrected serum concentrations of clozapine and its main metabolite norclozapine were retrospectively analyzed in 45 patients receiving both clozapine and valproic acid. Controls were matched for sex, age, smoking, comedication, and inflammatory response. RESULTS The group receiving comedication with valproic acid showed significantly lower median dose-corrected serum concentrations of norclozapine (0.44 [0.27-0.58] (ng/mL)/(mg/d) vs 0.78 [0.60-1.07] (ng/mL)/(mg/d)) as well as metabolite to parent compound ratios (0.40 [0.36-0.47] vs 0.71 [0.58-0.84]) by approximately 44%. Dose-corrected serum concentrations of clozapine were not significantly lower. The effect of valproic acid was independent of sex and smoking. CONCLUSIONS Comedication with valproic acid accelerated metabolism of clozapine with predominant effects on the degradation of norclozapine. Therapeutic drug monitoring should be applied to guide individual patient responses upon initiation of comedication.
Collapse
|
32
|
Sodium valproate and clozapine induced neutropenia: A case control study using register data. Schizophr Res 2018; 195:267-273. [PMID: 28882687 DOI: 10.1016/j.schres.2017.08.041] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 08/20/2017] [Accepted: 08/21/2017] [Indexed: 01/27/2023]
Abstract
BACKGROUND The use of clozapine is limited due to the occurrence of neutropenia, and the rare but life threatening adverse event of agranulocytosis. There is little epidemiological research into clinical factors that may impact on this risk. We conducted a case control study examining the clinical risk factors for neutropenia patients treated with clozapine. METHOD A case-control study was conducted within a database of anonymised electronic clinical records. All patients who discontinued clozapine due to a neutropenic event were included as cases. Matched controls were selected from patients with a documented clozapine exposure at the time of the clozapine neutropenic event of the case patient, matched by duration of clozapine treatment. RESULTS 136 cases and 136 controls were included. In multivariable analysis, the concurrent use of sodium valproate was associated with neutropenia (Odds Raito (OR) 2.28, 95%CI: 1.27-4.11, p=0.006). There was a dose-response effect, with greater associations for higher doses. Patients who discontinued clozapine due to neutropenia were more likely to be of black ethnicity (OR 2.99, p<0.001), were younger (t=5.86, df=267, p<0.001), and received lower doses of clozapine (t=-2.587, p=0.01) than those who did not develop neutropenia. CONCLUSION We identified an association between the concurrent use of sodium valproate and an increased risk of clozapine associated neutropenia. These results, taken in combination with the results from previous case series, suggest that the risk of clozapine associated neutropenia could be reduced by avoiding concurrent valproate treatment.
Collapse
|
33
|
Diaz FJ. Estimating individual benefits of medical or behavioral treatments in severely ill patients. Stat Methods Med Res 2017; 28:911-927. [DOI: 10.1177/0962280217739033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
There is a need for statistical methods appropriate for the analysis of clinical trials from a personalized-medicine viewpoint as opposed to the common statistical practice that simply examines average treatment effects. This article proposes an approach to quantifying, reporting and analyzing individual benefits of medical or behavioral treatments to severely ill patients with chronic conditions, using data from clinical trials. The approach is a new development of a published framework for measuring the severity of a chronic disease and the benefits treatments provide to individuals, which utilizes regression models with random coefficients. Here, a patient is considered to be severely ill if the patient’s basal severity is close to one. This allows the derivation of a very flexible family of probability distributions of individual benefits that depend on treatment duration and the covariates included in the regression model. Our approach may enrich the statistical analysis of clinical trials of severely ill patients because it allows investigating the probability distribution of individual benefits in the patient population and the variables that influence it, and we can also measure the benefits achieved in specific patients including new patients. We illustrate our approach using data from a clinical trial of the anti-depressant imipramine.
Collapse
Affiliation(s)
- Francisco J Diaz
- Department of Biostatistics, The University of Kansas Medical Center, Kansas City, KS, USA
| |
Collapse
|
34
|
Descoeur J, Philibert L, Chalard K, Attal J, Petit P, Klouche K, Olivier M. Success of tardive electroconvulsive therapy sessions after loxapine-induced malignant syndrome in the context of very poor metabolisation. Therapie 2017. [PMID: 28647110 DOI: 10.1016/j.therap.2017.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We report the success of tardive electroconvulsive therapy in a case of loxapine malignant syndrome with catatonia. Loxapine and its metabolites were measured in biological samples by liquid chromatography coupled to tandem mass spectrometry. Genes were studied by sequencing and quantitative polymerase chain reaction (PCR). Plasmatic drug concentrations showed a supratherapeutic concentration of loxapine with a very low 8-hydroxyloxapine/loxapine ratio (range from 0.32 to 0.66, normal value>2 for 100mg) and a very long elimination half-life of loxapine (half-life>140h, normal value from 1 to 4hours). We tried to explain this kinetics by exploring the main pharmacogenes implicated in the metabolism of loxapine. No genetic abnormality for CYP1A2 was observed. The study of associated treatments showed the potential contribution of valproate. Pharmacokinetics and pharmacogenetics investigations revealed a blockade of the CYP1A2 metabolic pathway without genetic abnormalities, probably due to valproate co-medication. Toxicological monitoring of loxapine and its metabolites helped to explain the persistence of symptoms and to adapt the therapeutic management.
Collapse
Affiliation(s)
- Juliette Descoeur
- Toxicology laboratory, department of medical pharmacology and toxicology, Lapeyronie hospital, CHRU of Montpellier, 34295 Montpellier cedex 5, France.
| | - Laurent Philibert
- Toxicology laboratory, department of medical pharmacology and toxicology, Lapeyronie hospital, CHRU of Montpellier, 34295 Montpellier cedex 5, France
| | - Kevin Chalard
- Department of anesthesia, hôpital de la colombière, CHU of Montpellier, 34295 Montpellier, France
| | - Jérôme Attal
- Department of adult psychiatry, hôpital de la colombière, CHU of Montpellier, 34295 Montpellier, France
| | - Pierre Petit
- Toxicology laboratory, department of medical pharmacology and toxicology, Lapeyronie hospital, CHRU of Montpellier, 34295 Montpellier cedex 5, France; University of Montpellier, 34000 Montpellier, France
| | - Kada Klouche
- University of Montpellier, 34000 Montpellier, France; Department of critical care, Lapeyronie university hospital, 34295 Montpellier, France
| | - Mathieu Olivier
- Toxicology laboratory, department of medical pharmacology and toxicology, Lapeyronie hospital, CHRU of Montpellier, 34295 Montpellier cedex 5, France; University of Montpellier, 34000 Montpellier, France; UMR 5569 hydrosciences, 34090 Montpellier, France
| |
Collapse
|
35
|
Kang M, Kim E, Winkler TE, Banis G, Liu Y, Kitchen CA, Kelly DL, Ghodssi R, Payne GF. Reliable clinical serum analysis with reusable electrochemical sensor: Toward point-of-care measurement of the antipsychotic medication clozapine. Biosens Bioelectron 2017; 95:55-59. [PMID: 28412661 DOI: 10.1016/j.bios.2017.04.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/29/2017] [Accepted: 04/10/2017] [Indexed: 12/31/2022]
Abstract
Clozapine is one of the most promising medications for managing schizophrenia but it is under-utilized because of the challenges of maintaining serum levels in a safe therapeutic range (1-3μM). Timely measurement of serum clozapine levels has been identified as a barrier to the broader use of clozapine, which is however challenging due to the complexity of serum samples. We demonstrate a robust and reusable electrochemical sensor with graphene-chitosan composite for rapidly measuring serum levels of clozapine. Our electrochemical measurements in clinical serum from clozapine-treated and clozapine-untreated schizophrenia groups are well correlated to centralized laboratory analysis for the readily detected uric acid and for the clozapine which is present at 100-fold lower concentration. The benefits of our electrochemical measurement approach for serum clozapine monitoring are: (i) rapid measurement (≈20min) without serum pretreatment; (ii) appropriate selectivity and sensitivity (limit of detection 0.7μM); (iii) reusability of an electrode over several weeks; and (iv) rapid reliability testing to detect common error-causing problems. This simple and rapid electrochemical approach for serum clozapine measurements should provide clinicians with the timely point-of-care information required to adjust dosages and personalize the management of schizophrenia.
Collapse
Affiliation(s)
- Mijeong Kang
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, United States; Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States
| | - Eunkyoung Kim
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, United States; Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States
| | - Thomas E Winkler
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States; MEMS Sensors and Actuators Laboratory (MSAL), University of Maryland, College Park, MD 20742, United States
| | - George Banis
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States; MEMS Sensors and Actuators Laboratory (MSAL), University of Maryland, College Park, MD 20742, United States
| | - Yi Liu
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, United States; Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States
| | - Christopher A Kitchen
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228, United States
| | - Deanna L Kelly
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228, United States
| | - Reza Ghodssi
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States; MEMS Sensors and Actuators Laboratory (MSAL), University of Maryland, College Park, MD 20742, United States; Department of Electrical and Computer Engineering, Institute for Systems Research, University of Maryland, College Park, MD 20742, United States
| | - Gregory F Payne
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, United States; Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States.
| |
Collapse
|
36
|
Fan HC, Lee HS, Chang KP, Lee YY, Lai HC, Hung PL, Lee HF, Chi CS. The Impact of Anti-Epileptic Drugs on Growth and Bone Metabolism. Int J Mol Sci 2016; 17:E1242. [PMID: 27490534 PMCID: PMC5000640 DOI: 10.3390/ijms17081242] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/20/2016] [Accepted: 07/28/2016] [Indexed: 12/13/2022] Open
Abstract
Epilepsy is a common neurological disorder worldwide and anti-epileptic drugs (AEDs) are always the first choice for treatment. However, more than 50% of patients with epilepsy who take AEDs have reported bone abnormalities. Cytochrome P450 (CYP450) isoenzymes are induced by AEDs, especially the classical AEDs, such as benzodiazepines (BZDs), carbamazepine (CBZ), phenytoin (PT), phenobarbital (PB), and valproic acid (VPA). The induction of CYP450 isoenzymes may cause vitamin D deficiency, hypocalcemia, increased fracture risks, and altered bone turnover, leading to impaired bone mineral density (BMD). Newer AEDs, such as levetiracetam (LEV), oxcarbazepine (OXC), lamotrigine (LTG), topiramate (TPM), gabapentin (GP), and vigabatrin (VB) have broader spectra, and are safer and better tolerated than the classical AEDs. The effects of AEDs on bone health are controversial. This review focuses on the impact of AEDs on growth and bone metabolism and emphasizes the need for caution and timely withdrawal of these medications to avoid serious disabilities.
Collapse
Affiliation(s)
- Hueng-Chuen Fan
- Department of Pediatrics, Tungs' Taichung Metroharbor Hospital, Wuchi, 435 Taichung, Taiwan.
- Department of Nursing, Jen-Teh Junior College of Medicine, Nursing and Management, 356 Miaoli, Taiwan.
| | - Herng-Shen Lee
- Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, 813 Kaohsiung, Taiwan.
| | - Kai-Ping Chang
- Department of Pediatrics, Taipei Veterans General Hospital, 112 Taipei, Taiwan.
| | - Yi-Yen Lee
- Division of Pediatric Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, 112 Taipei, Taiwan.
- Faculty of Medicine, National Yang-Ming University, 112 Taipei, Taiwan.
| | - Hsin-Chuan Lai
- Department of Pediatrics, Tungs' Taichung Metroharbor Hospital, Wuchi, 435 Taichung, Taiwan.
- Department of Nursing, Jen-Teh Junior College of Medicine, Nursing and Management, 356 Miaoli, Taiwan.
| | - Pi-Lien Hung
- Department of Pediatrics, Kaohsiung Chang Gung Medical Center, 833 Kaohsiung, Taiwan.
| | - Hsiu-Fen Lee
- Department of Pediatrics, Taichung Veterans General Hospital, 407 Taichung, Taiwan.
| | - Ching-Shiang Chi
- Department of Pediatrics, Tungs' Taichung Metroharbor Hospital, Wuchi, 435 Taichung, Taiwan.
- Department of Nursing, Jen-Teh Junior College of Medicine, Nursing and Management, 356 Miaoli, Taiwan.
| |
Collapse
|
37
|
Citrome L, McEvoy JP, Saklad SR. A Guide to the Management of Clozapine-Related Tolerability and Safety Concerns. CLINICAL SCHIZOPHRENIA & RELATED PSYCHOSES 2016:CSRP.SACI.070816. [PMID: 27454214 DOI: 10.3371/csrp.saci.070816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Clozapine is a highly effective antipsychotic medication, which provides a range of significant benefits for patients with schizophrenia, and is the standard of care for treatment-resistant schizophrenia as well as for reducing the risk of suicidal behaviors in schizophrenia and schizoaffective disorder. However, clozapine is widely underutilized, largely because prescribing clinicians lack experience in prescribing it and managing its adverse events (AEs). Clozapine is associated with 3 uncommon but immediately dangerous AEs, agranulocytosis, myocarditis/cardiomyopathy, and seizures, as well as AEs that may become dangerous if neglected, including weight gain, metabolic syndrome and constipation, and others that are annoying or distressing such as sedation, nighttime enuresis and hypersalivation. Because of the risk of agranulocytosis, clozapine formulations are available only through restricted distribution via a patient registry, with mandatory, systematized monitoring for absolute neutrophil count using a specific algorithm. We identified articles on managing clozapine-associated AEs by searching PubMed using appropriate keywords and search techniques for each topic. A review of the prevalence and clinical characteristics of clozapine-associated AEs shows that these risks can be managed efficiently and effectively. The absolute risks for both agranulocytosis and myocarditis/cardiomyopathy are low, diminish after the first 6 months, and are further reduced with appropriate monitoring. Weight gain/metabolic disorders and constipation, which develop more gradually, can be mitigated with regular monitoring and timely interventions. Sedation, hypersalivation, and enuresis are common but manageable with ameliorative measures and/or medications.
Collapse
Affiliation(s)
| | | | - Stephen R Saklad
- 3 College of Pharmacy, University of Texas at Austin, Austin, TX, USA
- 4 Pharmacotherapy Education and Research Center, UT Health Science Center San Antonio, San Antonio, TX, USA
| |
Collapse
|
38
|
Diaz FJ. Measuring the individual benefit of a medical or behavioral treatment using generalized linear mixed-effects models. Stat Med 2016; 35:4077-92. [PMID: 27323698 DOI: 10.1002/sim.7005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 05/07/2016] [Accepted: 05/11/2016] [Indexed: 11/06/2022]
Abstract
We propose statistical definitions of the individual benefit of a medical or behavioral treatment and of the severity of a chronic illness. These definitions are used to develop a graphical method that can be used by statisticians and clinicians in the data analysis of clinical trials from the perspective of personalized medicine. The method focuses on assessing and comparing individual effects of treatments rather than average effects and can be used with continuous and discrete responses, including dichotomous and count responses. The method is based on new developments in generalized linear mixed-effects models, which are introduced in this article. To illustrate, analyses of data from the Sequenced Treatment Alternatives to Relieve Depression clinical trial of sequences of treatments for depression and data from a clinical trial of respiratory treatments are presented. The estimation of individual benefits is also explained. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Francisco J Diaz
- Department of Biostatistics, The University of Kansas Medical Center, Mail Stop 1026, 3901 Rainbow Blvd., Kansas City, 66160, KS, U.S.A
| |
Collapse
|
39
|
Spina E, Pisani F, de Leon J. Clinically significant pharmacokinetic drug interactions of antiepileptic drugs with new antidepressants and new antipsychotics. Pharmacol Res 2016; 106:72-86. [DOI: 10.1016/j.phrs.2016.02.014] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 02/08/2016] [Accepted: 02/11/2016] [Indexed: 12/14/2022]
|
40
|
Suspected Secondhand Smoke and Clozapine Toxicity. PSYCHOSOMATICS 2015; 56:707-9. [DOI: 10.1016/j.psym.2015.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 03/10/2015] [Accepted: 03/11/2015] [Indexed: 11/18/2022]
|
41
|
Three patients needing high doses of valproic Acid to get therapeutic concentrations. Case Rep Psychiatry 2015; 2015:542862. [PMID: 26000191 PMCID: PMC4427013 DOI: 10.1155/2015/542862] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/08/2015] [Indexed: 11/17/2022] Open
Abstract
Valproic acid (VPA) can autoinduce its own metabolism. Cases requiring VPA doses >4000 mg/day to obtain therapeutic plasma concentrations, such as these 3 cases, have never been published. Case 1 received VPA for seizures and schizophrenia and had >50 VPA concentrations in 4 years. A high dose of 5,250 mg/day of VPA concentrate was prescribed for years but this dose led to an intoxication when switched to the enterocoated divalproex sodium formulation, requiring a normal dose of 2000 mg/day. VPA metabolic capacity was significantly higher (t = −9.6; df = 6.3, p < 0.001) during the VPA concentrate therapy, possibly due to autoinduction in that formulation. Case 2 had VPA for schizoaffective psychosis with 10 VPA concentrations during an 8-week admission. To maintain a VPA level ≥50 μg/mL, VPA doses increased from 1500 to 4000 mg/day. Case 3 had tuberous sclerosis and epilepsy and was followed up for >4 years with 137 VPA concentrations. To maintain VPA concentrations ≥50 μg/mL, VPA doses increased from 3,375 to 10,500 mg/day. In Cases 2 and 3, the duration of admission and the VPA dose were strongly correlated (r around 0.90; p < 0.001) with almost no change after controlling for VPA concentrations, indicating progressive autoinduction that increased with time.
Collapse
|