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Evaluating Therapeutic Equivalence of Generic and Original Levetiracetam in Patients with Epilepsy: A Retrospective Study. Neurol Int 2022; 14:271-283. [PMID: 35324578 PMCID: PMC8953522 DOI: 10.3390/neurolint14010022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 03/02/2022] [Accepted: 03/11/2022] [Indexed: 02/01/2023] Open
Abstract
The brand interchangeability of antiepileptic drugs (AEDs) is a topic of debate, especially regarding their therapeutic equivalence. This study evaluates the efficacy and tolerability of generic levetiracetam compared to the brand-name equivalent in a routine clinical setting. We conducted a retrospective study, examining patients with stable seizure frequency who received generic levetiracetam after the brand-name drug. During the six-month substitution period, changes in seizure frequency, hospitalization due to seizure exacerbation, adverse events, composite outcomes related to adjusting the AED dosage, and switching back to original levetiracetam were analyzed. Seventy-five patients were enrolled; the majority (85.3%) had focal onset seizures, and almost half (49.3%) had refractory epilepsy. Six months after the substitution, the mean seizure frequency per month was not significantly different (3.15 ± 14.47 vs. 2.77 ± 11.41; p = 0.970). In patients with controlled seizures before the change, the seizure frequency increased significantly (0.56 ± 1.83 vs. 0.03 ± 0.16; p = 0.012). Adverse events occurred in six patients. We have observed recurrent seizures or adverse events from 14 days after the transition. The original drug return rates due to recurrent seizures and adverse events were 5.3% and 1.3%, respectively. Generic levetiracetam might not show therapeutic equivalence to the original molecule, especially in patients adequately controlled by the brand-name drug.
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梁 明, 邱 炜, 张 静, 黎 雪, 石 港, 翟 琼, 张 宇, 陈 志. Efficacy and safety of switching from brand-name to domestic generic levetiracetam in children with epilepsy. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2022; 24:285-289. [PMID: 35351259 PMCID: PMC8974645 DOI: 10.7499/j.issn.1008-8830.2111033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
OBJECTIVES To study the efficacy and safety of domestic generic levetiracetam in replacement of brand-name levetiracetam in the treatment of children with epilepsy. METHODS A retrospective analysis was performed on the medical data of 154 children with epilepsy who received domestic generic levetiracetam in the inpatient or outpatient service of Guangdong Provincial People's Hospital from May 2019 to December 2020. Domestic generic levetiracetam and brand-name levetiracetam were compared in terms of efficacy and safety. RESULTS For these 154 children, the epilepsy control rate was 77.3% (119/154) at baseline. At 6 months after switching to domestic generic levetiracetam, the epilepsy control rate reached 83.8% (129/154), which showed a significant increase (P<0.05). There was no significant change in the frequency of seizures from baseline to 6 months after switching (P>0.05). The incidence of refractory epilepsy in children with no response after switching treatment was significantly higher than that in children with response (P<0.05). Before switching, only 1 child (0.6%) experienced somnolence, while after switching, 3 children (1.9%) experienced mild adverse drug reactions, including dizziness, somnolence, irritability, and bad temper. CONCLUSIONS Switching from brand-name to generic levetiracetam is safe and effective and holds promise for clinical application, but more prospective randomized controlled trials are required in future.
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Affiliation(s)
- 明娟 梁
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
| | - 炜凤 邱
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
- 汕头大学医学院,广东汕头515041
| | - 静雯 张
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
| | - 雪萍 黎
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
- 汕头大学医学院,广东汕头515041
| | - 港安 石
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
| | - 琼香 翟
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
| | - 宇昕 张
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
| | - 志红 陈
- 广东省人民医院/广东省医学科学院儿科, 广东广州510080
- 汕头大学医学院,广东汕头515041
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Frade VP, Paiva MJND, Martins I, Castro WVD, Belo VS, Baldoni AO, Lima PDF, Sanches C. Interchangeability among carbamazepine formulations: the impact over epilepsy patients. BRAZ J PHARM SCI 2022. [DOI: 10.1590/s2175-97902022e19594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Tassi L, Specchio N, Mecarelli O, Tinuper P, Vigevano F, Perucca E. The 50th anniversary of the Italian League Against Epilepsy (Lega Italiana Contro l’Epilessia). Epilepsy Behav Rep 2022; 19:100553. [PMID: 35664663 PMCID: PMC9157453 DOI: 10.1016/j.ebr.2022.100553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 05/11/2022] [Accepted: 05/15/2022] [Indexed: 11/17/2022] Open
Abstract
We describe the 50-year history of the Italian League Against Epilepsy (LICE). LICE promotes high-quality epilepsy care, education and research into epilepsy. LICE maintains close relations with ILAE and other professional societies.
This article was prepared to outline the article collection submitted on behalf of Lega Italiana Contro l’Epilepsia, or LICE, for the 50th anniversary of the founding of the ILAE Italian Chapter, and provides a brief summary of the history, with its landmark achievements and challenges. LICE is a multidisciplinary, inclusive, educational, informative and multifaceted organization. Initially in 1955 and then formally in 1972, LICE was born in Milano, with the mission to devote itself to people suffering with epilepsy and by promoting appropriate treatment and care, integration into society, to promote and pursue all kinds of activities designed to achieve those aims. The LICE is currently composed of more than 1000 members including neurologists, pediatric neurologists, neurosurgeons, neurophysiologists, and neuropsychologists who function throughout Italy dealing mainly or exclusively with the diagnosis and treatment of people with epilepsy.
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Roberti R, Casarella A, Iudice A, La Neve A, Beghi E, Capovilla G, Di Bonaventura C, Giorgi FS, Grosso S, Iannone LF, Romigi A, Specchio LM, Zaccara G, Mecarelli O, Russo E. Appropriate use of generic and branded antiseizure medications in epilepsy: Updated recommendations from the Italian League Against Epilepsy (LICE). Epilepsy Behav 2021; 116:107804. [PMID: 33581599 DOI: 10.1016/j.yebeh.2021.107804] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/03/2020] [Accepted: 01/14/2021] [Indexed: 02/05/2023]
Abstract
Generic drugs are increasingly used to treat many diseases including epilepsy. The growing importance of generic antiseizure medications (ASMs) has led the ASMs commission of the Italian League Against Epilepsy (LICE) to review current evidence in the literature about efficacy and safety of these products. Recommendations from other scientific organizations have also been considered to provide an update of the LICE position about their utilization (List of Recommendations). Compared with the previous literature review, randomized controlled trials assessing bioequivalence among branded drugs and generics are currently available. Although some contrasting results have been reported, brand-to-generic switching was effective and tolerable in real-life settings, with similar adverse event ratios. Based on these findings, LICE concluded that, conforming to the rigorous regulation of USA and EU markets, generic ASMs are not inferior to the respective branded, providing a cost advantage for patients starting or replacing monotherapy or add-on, and for those with incomplete seizure control. Branded-to-generic (and vice versa) switching is not recommended (although applicable) during seizure remission, as well as the generic-to-other generic switching. Other recommendations focus on the appropriateness of therapeutic drug monitoring (TDM) when switching is required, paying attention to avoiding the erroneous switch between modified and immediate-release formulations during dispensation. Finally, to support patients' compliance, they should be assured of generics' safety and efficacy and carefully informed with practical advice, particularly when the switching is associated with aspect modifications (e.g. color and shape changes) of the pill or the packaging.
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Affiliation(s)
- Roberta Roberti
- Science of Health Department, School of Medicine, University of Catanzaro, Italy
| | - Alessandro Casarella
- Science of Health Department, School of Medicine, University of Catanzaro, Italy
| | - Alfonso Iudice
- Department of Clinical and Experimental Medicine, Section of Neurology, University of Pisa, Pisa, Italy
| | - Angela La Neve
- Department of Neurological and Psychiatric Sciences, Centre for Epilepsy, University of Bari, Bari, Italy
| | - Ettore Beghi
- Laboratory of Neurological Disorders, Department of Neuroscience, Institute for Pharmacological Research, IRCCS-Mario Negri Milan, Italy
| | - Giuseppe Capovilla
- Department of Mental Health, Epilepsy Center, C. Poma Hospital, Mantua, Italy and Fondazione Poliambulanza, Brescia, Italy
| | - Carlo Di Bonaventura
- Neurology Unit, Department of Human Neurosciences, "Sapienza" University, Rome, Italy
| | - Filippo S Giorgi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy; Neurology, Pisa University Hospital, Pisa, Italy
| | - Salvatore Grosso
- Clinical Pediatrics, Department of Pediatrics, University of Siena
| | - Luigi F Iannone
- Science of Health Department, School of Medicine, University of Catanzaro, Italy
| | - Andrea Romigi
- Department of Neurology, Mediterranean Neurological Institute, Pozzilli, Italy
| | | | | | - Oriano Mecarelli
- Neurology Unit, Human Neurosciences Department, Sapienza University, Umberto 1 Hospital, Rome, Italy
| | - Emilio Russo
- Science of Health Department, School of Medicine, University of Catanzaro, Italy.
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Abstract
BACKGROUND Antiepileptic drugs (AEDs) are the mainstay of epilepsy treatment. Since 1989, 18 new AEDs have been licensed for clinical use and there are now 27 licensed AEDs in total for the treatment of patients with epilepsy. Furthermore, several AEDs are also used for the management of other medical conditions, for example, pain and bipolar disorder. This has led to an increasingly widespread application of therapeutic drug monitoring (TDM) of AEDs, making AEDs among the most common medications for which TDM is performed. The aim of this review is to provide an overview of the indications for AED TDM, to provide key information for each individual AED in terms of the drug's prescribing indications, key pharmacokinetic characteristics, associated drug-drug pharmacokinetic interactions, and the value and the intricacies of TDM for each AED. The concept of the reference range is discussed as well as practical issues such as choice of sample types (total versus free concentrations in blood versus saliva) and sample collection and processing. METHODS The present review is based on published articles and searches in PubMed and Google Scholar, last searched in March 2018, in addition to references from relevant articles. RESULTS In total, 171 relevant references were identified and used to prepare this review. CONCLUSIONS TDM provides a pragmatic approach to epilepsy care, in that bespoke dose adjustments are undertaken based on drug concentrations so as to optimize clinical outcome. For the older first-generation AEDs (carbamazepine, ethosuximide, phenobarbital, phenytoin, primidone, and valproic acid), much data have accumulated in this regard. However, this is occurring increasingly for the new AEDs (brivaracetam, eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, perampanel, piracetam, pregabalin, rufinamide, stiripentol, sulthiame, tiagabine, topiramate, vigabatrin, and zonisamide).
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Grabowski DC, Fishman J, Wild I, Lavin B. Changing the neurology policy landscape in the United States: Misconceptions and facts about epilepsy. Health Policy 2018; 122:797-802. [PMID: 29908672 DOI: 10.1016/j.healthpol.2018.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 05/09/2018] [Accepted: 05/21/2018] [Indexed: 12/15/2022]
Abstract
Epilepsy has a relatively high prevalence, and diagnosis and treatment are often challenging. Seizure freedom without significant side effects is the ultimate goal for both physicians and patients, but not always achievable. In those cases, the treatment goals of patients and providers may differ. In the United States, many clinicians continue to prescribe older AEDs, even though newer AEDs have a more desirable safety and tolerability profile, fewer drug-drug interactions, and are associated with lower epilepsy-related hospital visits. Newer AEDs are more commonly prescribed by neurologists and epilepsy center physicians, highlighting the importance of access to specialty care. We report that antiepileptic drugs are not the dominant cost driver for patients with epilepsy and costs are considerably higher in patients with uncontrolled epilepsy. Poor drug adherence is considered a main cause of unsuccessful epilepsy treatment and is associated with increases in inpatient and emergency department admissions and related costs. Interventions and educational programs are needed to address the reasons for nonadherence. Coverage policies placing a higher cost burden on patients with epilepsy lead to lower treatment adherence, which can result in higher future health care spending. Epilepsy is lagging behind other neurological conditions in terms of funding and treatment innovation. Increased investment in epilepsy research may be particularly beneficial given current funding levels and the high prevalence of epilepsy.
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Affiliation(s)
- David C Grabowski
- Department of Health Care Policy, Harvard Medical School, 180 Longwood Avenue, Boston, MA, 02115-5899, USA.
| | - Jesse Fishman
- UCB Pharma, 1950 Lake Park Drive SE, Smyrna, GA 30080, USA.
| | - Imane Wild
- UCB Pharma, 1950 Lake Park Drive SE, Smyrna, GA 30080, USA.
| | - Bruce Lavin
- UCB Pharma, 1950 Lake Park Drive SE, Smyrna, GA 30080, USA.
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Trimboli M, Russo E, Mumoli L, Tripepi G, Fortunato F, Mastroianni G, Abate F, De Sarro G, Gambardella A, Labate A. Brand-to-generic levetiracetam switching: a 4-year prospective observational real-life study. Eur J Neurol 2018; 25:666-671. [DOI: 10.1111/ene.13568] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 12/27/2017] [Indexed: 11/29/2022]
Affiliation(s)
- M. Trimboli
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
| | - E. Russo
- Science of Health Department; School of Medicine; University Magna Graecia; Catanzaro Italy
| | - L. Mumoli
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
| | - G. Tripepi
- Institute of Clinical Physiology; Research Unit of Reggio Calabria; National Research Council (IFC-CNR); Reggio Calabria Italy
| | - F. Fortunato
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
| | - G. Mastroianni
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
| | - F. Abate
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
| | - G. De Sarro
- Science of Health Department; School of Medicine; University Magna Graecia; Catanzaro Italy
| | - A. Gambardella
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
| | - A. Labate
- Department of Medical Sciences; Institute of Neurology; University Magna Graecia; Catanzaro Italy
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Switch From Originator to Equivalent Drug in the Era of Generic Antiepileptic Drugs: Study of Keppra Versus Epitiram Clinical Equivalence. Clin Neuropharmacol 2017; 40:239-242. [DOI: 10.1097/wnf.0000000000000250] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bosak M, Słowik A, Turaj W. Safety of switching from brand-name to generic levetiracetam in patients with epilepsy. DRUG DESIGN DEVELOPMENT AND THERAPY 2017; 11:2287-2291. [PMID: 28814836 PMCID: PMC5546726 DOI: 10.2147/dddt.s138270] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Purpose The approach to the use of generic antiepileptic drugs has recently evolved from major concern to general acceptance, but the evidence related specifically to the safety of switching from brand-name to generic levetiracetam (LEV) is scarce. The aim of the study was to assess the risk of increased frequency of seizures or other adverse events after replacement of a brand-name LEV with a generic one. Patients and methods This retrospective analysis included 159 patients treated with LEV in a tertiary outpatient epilepsy clinic. We included all patients diagnosed with epilepsy who were treated with LEV as at March 1, 2013. Most patients were forced to switch to the generic LEV because of the sudden rise in cost of the branded LEV. We recorded data on age, sex, age at onset of epilepsy, type of epilepsy, and its treatment. We analyzed data from one visit before potential switching and from two visits after the potential switching. The interval between visits was typically 3 months. We registered an increase in the frequency of seizures and in the occurrence of adverse events. Results Among 151 subjects who switched to generic LEV after March 1, 2013, increased frequency of seizures was noted in 9 patients (6%) during the first follow-up visit. Patients with increased frequency of seizures did not differ from other patients regarding sex, age, age at the onset of epilepsy, and the median dose of LEV before switching or the median duration of treatment with LEV before switching. Two patients returned to brand-name LEV. Adverse events were noted in six other patients (4%) and included somnolence, irritability, or dizziness. Conclusion Switching from brand-name to generic LEV is generally safe.
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Affiliation(s)
- Magdalena Bosak
- Department of Neurology, Jagiellonian University Medical College, Kraków, Poland
| | - Agnieszka Słowik
- Department of Neurology, Jagiellonian University Medical College, Kraków, Poland
| | - Wojciech Turaj
- Department of Neurology, Jagiellonian University Medical College, Kraków, Poland
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Kwan P, Palmini A. Association between switching antiepileptic drug products and healthcare utilization: A systematic review. Epilepsy Behav 2017. [PMID: 28641169 DOI: 10.1016/j.yebeh.2017.05.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AIMS There is ongoing concern whether switching between different antiepileptic drug (AED) products may compromise patient care. We systematically reviewed changes in healthcare utilization following AED switch. METHODS We searched MEDLINE and EMBASE databases (1980-October 2016) for studies that assessed the effect of AED switching in patients with epilepsy on outpatient visits, emergency room visits, hospitalization and hospital stay duration. RESULTS A total of 14 articles met the inclusion criteria. All were retrospective studies. Four provided findings for specific AEDs only (lamotrigine, topiramate, phenytoin and divalproex), 9 presented pooled findings from multiple AEDs, and 1 study provided both specific (lamotrigine, topiramate, oxcarbazepine, and levetiracetam) and pooled findings. Three studies found an association between a switch of topiramate and an increase in healthcare utilization. Another three studies found that a brand-to-generic lamotrigine switch was not associated with an increased risk of emergently treated events (ambulance use, ER visits or hospitalization). The outcomes of the pooled AED switch studies were inconsistent; 5 studies reported an increased healthcare utilization while 5 studies did not. CONCLUSION Studies that have examined the association between an AED switch and a change in healthcare utilization report conflicting findings. Factors that may explain these inconsistent outcomes include inter-study differences in the type of analysis undertaken (pooled vs individual AED data), the covariates used for data adjustment, and the type of switch examined. Future medical claim database studies employing a prospective design are encouraged to address these and other factors in order to enhance inter-study comparability and extrapolation of findings.
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Affiliation(s)
- Patrick Kwan
- Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia; Department of Neurology, Royal Melbourne Hospital, Parkville, Victoria, Australia.
| | - André Palmini
- Faculty of Medicine, Neurology Service & Porto Alegre Epilepsy Surgery Program, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Brazil.
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Alyautdin RN, Romanov BK, Pasternak EY, Bunyatyan ND, Merkulov VA. Analysis of Factors Influencing the Interchangeability of Antiepileptic Drugs. Pharm Chem J 2016. [DOI: 10.1007/s11094-016-1418-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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13
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Intrapatient variation in antiepileptic drug plasma concentration after generic substitution vs stable brand-name drug regimens. Epilepsy Res 2016; 122:79-83. [PMID: 26987080 DOI: 10.1016/j.eplepsyres.2016.02.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 01/21/2016] [Accepted: 02/28/2016] [Indexed: 11/20/2022]
Abstract
Generic substitution of antiepileptic drugs (AEDs) is still a matter of controversy and concern among clinicians and patients. We aimed to assess intrasubject variation in plasma concentrations of lamotrigine (LTG), levetiracetam (LEV) and topiramate (TPM) after generic substitution compared with a stable brand-name drug regimen in a population of patients with epilepsy. A retrospective analysis was performed on prospectively collected and stored data from our therapeutic drug monitoring (TDM) database for the years 2009-2014. The main outcome variable was the proportion of patients who, after switching from branded to generic formulations, showed a greater than ±20% change in AED plasma concentrations compared to the proportion of control patients showing a change in AED plasma concentrations of the same extent while receiving stable branded formulations over repeated TDM tests. Fifty patients on LTG, 27 on LEV and 16 on TPM showing at least one TDM test while receiving generic products fulfilled the inclusion/exclusion criteria for the analysis and were compared with 200 control patients for LTG, 120 for LEV and 80 for TPM. The proportion of patients showing an intrasubject change greater than ±20% in AED plasma concentrations was similar in the brand name vs generic group compared with the control one for LTG (22% vs 33%) and LEV (44% vs 38%), while it was higher in the control group for TPM (41% vs 6%, p<0.01). These are the first data in the literature about the within-patient variation in steady-state plasma concentrations of a series of stable treatments with brand-name AEDs in a real clinical setting. In conclusion, a significant interday variability in intrapatient LTG, LEV and TPM plasma concentrations can be observed even in patients stabilized with the same brand name product over time. This suggests that any change in plasma AED concentration and possible related clinical effects after generic substitution may be not necessarily related to the switch. Our results should be confirmed by large, prospective, blinded, randomized controlled studies in people with epilepsy.
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Atif M, Azeem M, Sarwar MR. Potential problems and recommendations regarding substitution of generic antiepileptic drugs: a systematic review of literature. SPRINGERPLUS 2016; 5:182. [PMID: 27026878 PMCID: PMC4766158 DOI: 10.1186/s40064-016-1824-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 02/15/2016] [Indexed: 12/22/2022]
Abstract
Despite the availability of generic antiepileptic drugs (AEDs), still patients and neurologists hesitate to make a switch due to assorted reasons. The objectives of this review were to evaluate the risks associated with the generic substitution of AEDs. In this context, we also summarized the recommendations of various international societies to treat epileptic patients. We used a number of electronic databases to identify the relevant published studies which demonstrated the potential problems and recommendations regarding generic substitution of AEDs. Of 204 articles found initially, 153 were selected for additional review. Subsequently, 68 articles were finally selected. This review concluded that potential problems linked with the generic substitution of AEDs could be bioequivalence issues, failure of drug therapy, emergence of adverse events and increase in the frequency of seizures. The reasons could be the pharmacokinetics properties of AEDs and unique characteristics of some epilepsy patients. Consequently, the generic substitution of AEDs affects the successful treatment and quality of life of the patients. Various guidelines recommend the well-controlled epileptic patients to avoid switching from brand-to-generic products, generic-to-brand products or generic to some other generic products.
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Affiliation(s)
- Muhammad Atif
- Department of Pharmacy, Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Bahawalpur, Punjab Pakistan
| | - Muhammad Azeem
- Department of Pharmacy, Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Bahawalpur, Punjab Pakistan
| | - Muhammad Rehan Sarwar
- Department of Pharmacy, Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Bahawalpur, Punjab Pakistan
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Polard E, Nowak E, Happe A, Biraben A, Oger E. Brand name to generic substitution of antiepileptic drugs does not lead to seizure-related hospitalization: a population-based case-crossover study. Pharmacoepidemiol Drug Saf 2015; 24:1161-9. [DOI: 10.1002/pds.3879] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 08/18/2015] [Accepted: 08/27/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Elisabeth Polard
- Department of Pharmacology, Pharmacovigilance, Pharmacoepidemiology and Drug Information Center; Rennes University Hospital; Rennes France
- Pharmacoepidemiology team (CTAD-PEPI); Rennes University Hospital; Rennes France
| | - Emmanuel Nowak
- Pharmacoepidemiology team (CTAD-PEPI); Rennes University Hospital; Rennes France
| | - André Happe
- Pharmacoepidemiology team (CTAD-PEPI); Rennes University Hospital; Rennes France
| | - Arnaud Biraben
- Department of Neurology; Rennes University Hospital; Rennes France
| | - Emmanuel Oger
- Department of Pharmacology, Pharmacovigilance, Pharmacoepidemiology and Drug Information Center; Rennes University Hospital; Rennes France
- Pharmacoepidemiology team (CTAD-PEPI); Rennes University Hospital; Rennes France
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Poluzzi E, Veronese G, Piccinni C, Raschi E, Koci A, Pagano P, Godman B, Marchesini G, Boriani G, De Ponti F. Switching among Equivalents in Chronic Cardiovascular Therapies: 'Real World' Data from Italy. Basic Clin Pharmacol Toxicol 2015; 118:63-9. [PMID: 26150075 DOI: 10.1111/bcpt.12442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/29/2015] [Indexed: 11/29/2022]
Abstract
Since August 2012, Italian general practitioners are required to prescribe the generic name of medicines, except for refill of chronic therapy. We evaluated the extent of switching among equivalents in chronic cardiovascular therapies, the influence of the 2012 regulatory intervention and of patient-related or drug-related factors. Prescriptions of off-patent anti-arrhythmics, oral antidiabetics and ACE inhibitors dispensed from August 2011 to August 2013 within the Bologna Local Health Authority (870,000 inhabitants) was collected. The rate of actual switching among equivalents was evaluated monthly. The effect of the regulatory intervention was estimated by interrupted-time-series analysis. Adjusted odds ratios (aORs) of switching were calculated for the following: age, gender, number of different equivalents available for each drug and change in dispensing pharmacy between subsequent refills. The average monthly rates of switches were 9.6%, 16.3% and 16.3% for anti-arrhythmics, antidiabetics and ACE inhibitors, respectively. Values significantly increased soon after the regulatory intervention for ACE inhibitors (+1.81%, p < 0.01), anti-arrhythmics (+1.46%, p = 0.01) and antidiabetics (+1.09%, p = 0.01), and no significant decreasing trends were observed in the following 12 months. For all drug classes, odd of switching was higher in case of change in dispensing pharmacy (up to aOR = 4.31, 95 CI = 4.26-4.35 for ACE inhibitors) and availability of ≥5 different equivalents (up to aOR = 7.82, 95 CI = 7.39-8.28 for antidiabetics). Switching was lower for age ≥65 for antidiabetics and ACE inhibitors (aOR = 0.92, 95 CI = 0.90-0.93; 0.87, 0.86-0.88, respectively). The Italian regulatory intervention generated an immediate increase, not sustained in time, in switching among equivalents of cardiovascular therapies. Young age, high number of available equivalents and changes in dispensing pharmacy between subsequent refills were associated with switching.
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Affiliation(s)
- Elisabetta Poluzzi
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Giacomo Veronese
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Carlo Piccinni
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Emanuel Raschi
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Ariola Koci
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Paola Pagano
- Drug Policy Department, Local Health Authority of Bologna, Bologna, Italy
| | - Brian Godman
- Division of Clinical Pharmacology, Karolinska Institute, Stockholm, Sweden.,Strathclyde Institute of Pharmacy and Biomedical Sciences, Strathclyde University, Glasgow, UK
| | - Giulio Marchesini
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Giuseppe Boriani
- Department of Clinical and Experimental Medicine, University of Bologna, Bologna, Italy
| | - Fabrizio De Ponti
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
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18
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Vaithianathan S, Raman S, Jiang W, Ting TY, Kane MA, Polli JE. Biopharmaceutic Risk Assessment of Brand and Generic Lamotrigine Tablets. Mol Pharm 2015; 12:2436-43. [DOI: 10.1021/acs.molpharmaceut.5b00154] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Soundarya Vaithianathan
- Department
of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, United States
| | - Siddarth Raman
- Department
of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, United States
| | - Wenlei Jiang
- Food and Drug Administration, Rockville, Maryland 20852, United States
| | - Tricia Y. Ting
- Department
of Neurology, University of Maryland, Baltimore, Maryland 21201, United States
| | - Maureen A. Kane
- Department
of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, United States
| | - James E. Polli
- Department
of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, United States
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19
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Gwaza L, Gordon J, Welink J, Potthast H, Leufkens H, Stahl M, García-Arieta A. Adjusted Indirect Treatment Comparison of the Bioavailability of WHO-Prequalified First-Line Generic Antituberculosis Medicines. Clin Pharmacol Ther 2014; 96:580-8. [DOI: 10.1038/clpt.2014.144] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 06/25/2014] [Indexed: 11/10/2022]
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20
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Sander JW, Ryvlin P, Stefan H, Booth DR, Bauer J. Generic substitution of antiepileptic drugs. Expert Rev Neurother 2014; 10:1887-98. [DOI: 10.1586/ern.10.163] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Abstract
Blood (serum/plasma) antiepileptic drug (AED) therapeutic drug monitoring (TDM) has proven to be an invaluable surrogate marker for individualizing and optimizing the drug management of patients with epilepsy. Since 1989, there has been an exponential increase in AEDs with 23 currently licensed for clinical use, and recently, there has been renewed and extensive interest in the use of saliva as an alternative matrix for AED TDM. The advantages of saliva include the fact that for many AEDs it reflects the free (pharmacologically active) concentration in serum; it is readily sampled, can be sampled repetitively, and sampling is noninvasive; does not require the expertise of a phlebotomist; and is preferred by many patients, particularly children and the elderly. For each AED, this review summarizes the key pharmacokinetic characteristics relevant to the practice of TDM, discusses the use of other biological matrices with particular emphasis on saliva and the evidence that saliva concentration reflects those in serum. Also discussed are the indications for salivary AED TDM, the key factors to consider when saliva sampling is to be undertaken, and finally, a practical protocol is described so as to enable AED TDM to be applied optimally and effectively in the clinical setting. Overall, there is compelling evidence that salivary TDM can be usefully applied so as to optimize the treatment of epilepsy with carbamazepine, clobazam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, primidone, topiramate, and zonisamide. Salivary TDM of valproic acid is probably not helpful, whereas for clonazepam, eslicarbazepine acetate, felbamate, pregabalin, retigabine, rufinamide, stiripentol, tiagabine, and vigabatrin, the data are sparse or nonexistent.
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22
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Nanau RM, Neuman MG. Adverse drug reactions induced by valproic acid. Clin Biochem 2013; 46:1323-38. [PMID: 23792104 DOI: 10.1016/j.clinbiochem.2013.06.012] [Citation(s) in RCA: 193] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/11/2013] [Accepted: 06/12/2013] [Indexed: 12/11/2022]
Abstract
Valproic acid is a widely-used first-generation antiepileptic drug, prescribed predominantly in epilepsy and psychiatric disorders. VPA has good efficacy and pharmacoeconomic profiles, as well as a relatively favorable safety profile. However, adverse drug reactions have been reported in relation with valproic acid use, either as monotherapy or polytherapy with other antiepileptic drugs or antipsychotic drugs. This systematic review discusses valproic acid adverse drug reactions, in terms of hepatotoxicity, mitochondrial toxicity, hyperammonemic encephalopathy, hypersensitivity syndrome reactions, neurological toxicity, metabolic and endocrine adverse events, and teratogenicity.
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Affiliation(s)
- Radu M Nanau
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, In Vitro Drug Safety and Biotechnology, Toronto, Ontario, Canada
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23
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Talati R, Scholle JM, Phung OP, Baker EL, Baker WL, Ashaye A, Kluger J, Coleman CI, White CM. Efficacy and safety of innovator versus generic drugs in patients with epilepsy: a systematic review. Pharmacotherapy 2012; 32:314-22. [PMID: 22461121 DOI: 10.1002/j.1875-9114.2012.01099.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Generic antiepileptic drugs achieve blood concentrations similar to those of innovator drugs in healthy volunteers, but their comparative effectiveness has not been well evaluated. Thus, we assessed the efficacy, tolerability, and safety of innovator versus generic antiepileptic drugs. We searched the MEDLINE database, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Web of Science for studies that evaluated innovator and generic antiepileptic drugs in patients with epilepsy and reported data on prespecified outcomes. We extracted data on study design, interventions, quality criteria, study population, baseline characteristics, and outcomes. Compared with initiation of innovator antiepileptic drugs, initiation of generic antiepileptic drugs did not significantly alter seizure occurrence (relative risk [RR] 0.87, 95% confidence interval [CI] 0.64-1.18; strength of evidence: low) or frequency (standardized mean difference 0.03, 95% CI -0.08-0.14; strength of evidence: low), withdrawals due to lack of efficacy (RR 1.02, 95% CI 0.41-2.54; strength of evidence: low) or adverse events (RR 0.79, 95% CI 0.28-2.20; strength of evidence: low), pharmacokinetic concentrations (maximum, minimum, or area under the curve [strength of evidence: low]), or a myriad of adverse events (strength of evidence: low or insufficient) in clinical trials. In qualitatively evaluated observational studies, switching between forms of antiepileptic drug (innovator to generic, generic to generic) may increase the risk of hospitalization (strength of evidence: low), hospital stay duration (strength of evidence: low), and a composite end point of medical service utilization (strength of evidence: insufficient) but may not increase outpatient service utilization (strength of evidence: low). Data are limited predominantly to carbamazepine, phenytoin, and valproic acid. Clinical trials are limited by small sample size, short-term nature, and lack of specification of A-rated generic products (generics that the United States Food and Drug Administration has deemed bioequivalent to the innovator drug). Observational trials lack full accounting for confounders and have inherent limitations. With a low strength of evidence, it appears that initiating an innovator or generic antiepileptic drug will provide similar efficacy, tolerability, and safety but that switching from one form to the other may be associated with more hospitalizations and longer hospital stays.
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Affiliation(s)
- Ripple Talati
- University of Connecticut/Hartford Hospital, Evidence-Based Practice Center, Hartford, Connecticut 06102-5037, USA
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24
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Gomes WA, Shinnar S. Prospects for imaging-related biomarkers of human epileptogenesis: a critical review. Biomark Med 2012; 5:599-606. [PMID: 22003908 DOI: 10.2217/bmm.11.66] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
To facilitate the study of epileptogenesis in humans, noninvasive biomarkers of epileptogenesis are required. No validated biomarker is currently available, but brain imaging techniques provide many attractive candidates. In this article we examine the imaging features of temporal lobe epilepsy, focusing on those that may precede the onset of epilepsy and correlate with epileptogenesis. Hippocampal volumetry and T(2) relaxometry are proposed as candidate biomarkers of epileptogenesis in temporal lobe epilepsy following febrile status epilepticus. Preliminary data suggest that these have promise, and the ongoing Consequences of Prolonged Febrile Seizures in Childhood (FEBSTAT) study will provide more conclusive evidence as to their validity. At this time there are no other clear candidates for imaging-related biomarkers of epileptogenesis in human studies.
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Affiliation(s)
- William A Gomes
- Comprehensive Epilepsy Management Center, Montefiore Medical Center, 111 E. 210th St, Bronx, NY 10467, USA
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25
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Acevedo C, Acevedo K. Epilepsy treatment in developing countries: drug treatment. HANDBOOK OF CLINICAL NEUROLOGY 2012; 108:925-941. [PMID: 22939076 DOI: 10.1016/b978-0-444-52899-5.00038-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Carlos Acevedo
- University of Los Andes, Clínica Alemana, Alemana, Santiago, Chile.
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26
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Trinka E, Krämer G, Graf M. Requirements for generic antiepileptic medicines: a clinical perspective. J Neurol 2011; 258:2128-32. [DOI: 10.1007/s00415-011-6126-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 05/25/2011] [Accepted: 05/26/2011] [Indexed: 11/27/2022]
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27
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Prescription patterns of antiepileptic drugs in patients with epilepsy in a nation-wide population. Epilepsy Res 2011; 95:51-9. [DOI: 10.1016/j.eplepsyres.2011.02.012] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 02/08/2011] [Accepted: 02/21/2011] [Indexed: 11/18/2022]
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28
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Chaluvadi S, Chiang S, Tran L, Goldsmith CE, Friedman DE. Clinical experience with generic levetiracetam in people with epilepsy. Epilepsia 2011; 52:810-5. [PMID: 21426334 DOI: 10.1111/j.1528-1167.2011.03025.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
PURPOSE To describe the clinical outcomes of a compulsory switch from branded to generic levetiracetam (LEV) among people with epilepsy (PWE) in an outpatient setting. METHODS We conducted a retrospective chart review of 760 unduplicated consecutive adult patients attending a tertiary care epilepsy clinic at Ben Taub General Hospital. On November 1, 2008 hospital policy required all patients receiving branded LEV to be automatically switched to generic LEV. We calculated the proportion of patients switching back to branded LEV and reasons for the switch back. KEY FINDINGS Of the 260 patients (34%) being prescribed LEV (generic and brand name) during the study period, 105 (42.9%) were switched back to brand name LEV by their treating physicians. Reasons for switch back included increase in seizure frequency (19.6% vs. 1.6%; p < 0.0001) and adverse effects (AEs) (3.3%). AEs included headache, fatigue, and aggression. Patient age was associated with switchback when controlling for gender, epilepsy classification, and treatment characteristics [relative risk (RR) 2.44; 95% confidence interval (CI) 2.09-2.84; p < 0.05)]. An increase in seizure frequency subsequent to generic substitution was associated with polytherapy compared to monotherapy (3.225; 1.512-6.880; p < 0.05). SIGNIFICANCE A significant proportion of patients in our cohort on generic LEV required switch back to the branded drug. Careful monitoring is imperative because a compulsory switch from branded to generic LEV may lead to poor clinical outcomes, with risk of AEs and increased seizure frequency.
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Affiliation(s)
- Siresha Chaluvadi
- Department of Neurology, Baylor College of Medicine, Houston, Texas, USA.
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29
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Hagemann G, Zinke J, Fuchs M, Witte OW. [Change from original preparations to generics. A case example with oxcarbazepine]. DER NERVENARZT 2010; 81:1498-1500. [PMID: 20509018 DOI: 10.1007/s00115-010-3033-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- G Hagemann
- Hans Berger Klinik für Neurologie, Friedrich-Schiller-Universität, Jena.
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30
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Gagne JJ, Avorn J, Shrank WH, Schneeweiss S. Refilling and switching of antiepileptic drugs and seizure-related events. Clin Pharmacol Ther 2010; 88:347-53. [PMID: 20631693 PMCID: PMC2996138 DOI: 10.1038/clpt.2010.90] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We sought to estimate the risk of seizure-related events associated with refilling prescriptions for antiepileptic drugs (AEDs) and to estimate the effect of switching between brand-name and generic drugs or between two generic versions of the same drug. We conducted a case-crossover study using health-care databases from British Columbia, Canada, among AED users who had an emergency room visit or hospitalization for seizure (index seizure-related event), defined using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) codes 345.xx (epilepsy and recurrent seizures) and 780.3x (convulsions), between 1997 and 2005. AED prescription refilling itself was associated with 2.3-fold elevated odds of seizure-related events when the refill occurred within 21 days before the index event (odds ratio (OR) 2.31; 95% confidence interval (CI) 1.56-3.44). The OR was 2.75 (95% CI 0.88-8.64) for refills that involved switching, yielding a refill-adjusted OR for switching of 1.19 (95% CI 0.35-3.99). Refilling the same AED prescription was associated with an elevated risk of seizure-related events whether or not the refill involved switching from a brand-name to a generic product.
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Affiliation(s)
- J J Gagne
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
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31
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Kesselheim AS, Stedman MR, Bubrick EJ, Gagne JJ, Misono AS, Lee JL, Brookhart MA, Avorn J, Shrank WH. Seizure outcomes following the use of generic versus brand-name antiepileptic drugs: a systematic review and meta-analysis. Drugs 2010; 70:605-21. [PMID: 20329806 DOI: 10.2165/10898530-000000000-00000] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The automatic substitution of bioequivalent generics for brand-name antiepileptic drugs (AEDs) has been linked by anecdotal reports to loss of seizure control. To evaluate studies comparing brand-name and generic AEDs, and determine whether evidence exists of superiority of the brand-name version in maintaining seizure control. English-language human studies identified in searches of MEDLINE, EMBASE and International Pharmaceutical Abstracts (1984 to 2009). Randomized controlled trials (RCTs) and observational studies comparing seizure events or seizure-related outcomes between one brand-name AED and at least one alternative version produced by a distinct manufacturer. We identified 16 articles (9 RCTs, 1 prospective nonrandomized trial, 6 observational studies). We assessed characteristics of the studies and, for RCTs, extracted counts for patients whose seizures were characterized as 'controlled' and 'uncontrolled'. Seven RCTs were included in the meta-analysis. The aggregate odds ratio (n = 204) was 1.1 (95% CI 0.9, 1.2), indicating no difference in the odds of uncontrolled seizure for patients on generic medications compared with patients on brand-name medications. In contrast, the observational studies identified trends in drug or health services utilization that the authors attributed to changes in seizure control. Although most RCTs were short-term evaluations, the available evidence does not suggest an association between loss of seizure control and generic substitution of at least three types of AEDs. The observational study data may be explained by factors such as undue concern from patients or physicians about the effectiveness of generic AEDs after a recent switch. In the absence of better data, physicians may want to consider more intensive monitoring of high-risk patients taking AEDs when any switch occurs.
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Affiliation(s)
- Aaron S Kesselheim
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02120, USA.
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Barrett MW. Prescribing generic antiepileptic drugs: Issues and concerns for nurse practitioners. JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS 2010; 22:300-304. [PMID: 20536627 DOI: 10.1111/j.1745-7599.2010.00511.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
PURPOSE To educate prescribing clinicians about bioequivalent standards for therapeutic equivalence of brand and generic antiepileptic drugs (AEDs) as more generic drugs come to market, and to increase awareness of practice and safety issues surrounding the use of these drugs for people with seizures. DATA SOURCES Information was gathered from a search of the scientific literature as well as the author's clinical experience. CONCLUSIONS Controversy exists regarding the therapeutic equivalence of brand and generic AEDs, even when bioequivalent standards are satisfied. Generic AEDs have been associated with breakthrough seizures and adverse events that may outweigh cost savings encouraged by third-party payors. Further research is needed comparing brand to generic drugs in a rigorous manner in order to make a consensus statement regarding the safety and equivalency of generic AEDs for all patient populations. IMPLICATIONS FOR PRACTICE Generic AEDs may be safely prescribed in certain situations if clinicians are aware of ethical, legal, and practice issues surrounding their use. Sufficient time should be spent educating patients, caregivers, and pharmacists about implications of a switch made without the knowledge of the patient and/or prescriber.
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Bialer M, Midha KK. Generic products of antiepileptic drugs: a perspective on bioequivalence and interchangeability. Epilepsia 2010; 51:941-50. [PMID: 20384761 DOI: 10.1111/j.1528-1167.2010.02573.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Most antiepileptic drugs (AEDs) are currently available as generic products, yet neurologists and patients are reluctant to switch to generics. Generic AEDs are regarded as bioequivalent to brand AEDs after meeting the average bioequivalence criteria; consequently, they are considered to be interchangeable with their respective brands without loss of efficacy and safety. According to the U.S. Food and Drug Administration (FDA) the present bioequivalence requirements are already so rigorous and constrained that there is little possibility that generics that meet regulatory bioequivalence criteria could lead to therapeutic problems. So is there a scientific rationale for the concerns about switching patients with epilepsy to bioequivalent generics? Herein we discuss the assessment of bioequivalence and propose a scaled-average bioequivalence approach where scaling of bioequivalence is carried out based on brand lot-to-lot variance as an alternative to the conventional bioequivalence test as a means to determine whether switching patients to generic formulations, or vice versa, is a safe and effective therapeutic option. Meeting the proposed scaled-average bioequivalence requirements will ensure that when an individual patient is switched, he or she has fluctuations in plasma levels similar to those from lot-to-lot of the brand reference levels and thus should make these generic products safely switchable without change in efficacy and safety outcomes.
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Affiliation(s)
- Meir Bialer
- Faculty of Medicine, Institute of Drug Research, School of Pharmacy and David R Bloom Center for Pharmacy, The Hebrew University of Jerusalem, Jerusalem, Israel.
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Abstract
ABSTRACT
As patent protection ends for the next generation of antiepileptic drugs (AEDs), a complex debate continues over generic substitution of AEDs. On one hand, generic drug formulations provide cost savings for patients and society. On the other hand, patients with epilepsy and physicians are wary about the adequacy and efficacy of the Food and Drug Administration's (FDA) standards for generics. This article reviews current and proposed bioequivalence test procedures, summarizes new generic AED formulations and their costs, and discusses potential pitfalls in the current standards. These shortcomings include certain pharmacokinetic factors and clinical pharmacologic factors that may affect bioequivalence of generic AEDs, and statistical limitations of the standards. While the drug concentration differences between the brand name drug and each generic formulation are unlikely to be substantial, the differences with generic-to-generic switches will be greater and potentially clinically significant. Conversely, owing to their more favorable pharmacokinetic profile, newer AEDs may be less prone to problems with generic substitution than older ones. Unfortunately, very few data are available to guide decisions regarding what is best for an individual patient. Based on new prediction methods, generic substitution should be safe for many patients but identifying them ultimately requires more rigorous study.
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Affiliation(s)
- Susan J. Shaw
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Neurology, University of Southern California, Keck School of Medicine, Los Angeles, California
- Rancho Los Amigos National Rehabilitation Center, Downey, California
| | - Adam L. Hartman
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland
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35
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Umstellungen zwischen Lamotrigin-Präparaten bei Epilepsiepatienten. DER NERVENARZT 2010; 81:423-34. [DOI: 10.1007/s00115-010-2933-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Reed RC, Meinhold J, Dutta S, Liu W, Qiu Y. What do the suffixes - XR, ER, Chrono, Chronosphere - really mean as it pertains to modified-release antiepileptic drugs? J Clin Pharm Ther 2010; 35:373-83. [DOI: 10.1111/j.1365-2710.2009.01117.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
The issues surrounding generic drug substitution in patients with epilepsy are complex. The substitution of one formulation of an antiepileptic drug (AED) for another is controversial. Well-reasoned and defensible cases can be made both for and against such substitution. Although regulatory agencies require that generic and proprietary drugs have similar pharmacokinetic bioequivalence data, their therapeutic efficacy may not necessarily be identical. The paroxysmal nature of epilepsy, the narrow therapeutic index of some AEDs, the need to individualize therapy to achieve seizure control, and the negative consequences of uncontrolled epilepsy distinguishes epilepsy from other clinical conditions. Epilepsy management with AEDs requires careful dose titration and consistent drug exposure at the optimal level for each patient, which can be altered if a different formulation of the AED is substituted. Unexpected variability in plasma concentrations could occur when a patient who has been receiving one formulation of an AED (generic or brand) receives an alternate formulation. Thus, no substitutions should be made for people with epilepsy without the knowledge and approval of the prescribing physician. Patients should be consulted about the substitution, with all risks and benefits carefully explained.
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38
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Le Corre P. Bio-équivalence et génériques de principes actifs à marge thérapeutique étroite. Presse Med 2010; 39:169-76. [DOI: 10.1016/j.lpm.2009.09.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 09/16/2009] [Accepted: 09/23/2009] [Indexed: 10/20/2022] Open
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Once-daily dosing is appropriate for extended-release divalproex over a wide dose range, but not for enteric-coated, delayed-release divalproex: evidence via computer simulations and implications for epilepsy therapy. Epilepsy Res 2009; 87:260-7. [PMID: 19892524 DOI: 10.1016/j.eplepsyres.2009.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 09/02/2009] [Accepted: 09/20/2009] [Indexed: 11/22/2022]
Abstract
Divalproex sodium extended-release (divalproex-ER), administered once-daily, maintains plasma valproic acid (VPA) concentrations for 24h, whereas enteric-coated, delayed-release divalproex sodium (divalproex) requires multiple-daily doses to do the same. We hypothesize that a once-daily divalproex regimen should not be administered to epilepsy patients requiring high total daily doses, e.g., 35.6-56 mg/kg/day, due to the potential for high (>125 mg/L) maximum VPA concentrations (C(max)). We examined the impact of once-daily dosing, divalproex vs. divalproex-ER, on steady-state plasma VPA concentration-time profiles at commonly used doses in monotherapy (uninduced) and polytherapy (hepatic enzyme-induced) virtual adult patients. Only the 1125 mg once-daily divalproex dose had mean C(max)<100mg/L; >or=2000 mg produced mean C(max)>or=125 mg/L. Mean divalproex C(min) was approximately 50 mg/L at two of four doses tested, whereas mean ER C(min) was >73 mg/L at all doses tested. Once-daily divalproex peak-trough fluctuation was 4.4-6.2-fold greater than once-daily divalproex-ER. We predict that excursions beyond the conventional recommended VPA plasma concentration range will commonly occur with high total mg daily doses (>or=2000 mg) of enteric-coated divalproex, if dosed once-daily, potentially producing clinical toxicity. This divalproex formulation should not be dosed once-daily at high total mg daily doses due to this risk. Divalproex-ER is the appropriate formulation for administration on a once-daily basis, especially if large total mg/day doses are required for the control of seizure activity.
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Steinhoff BJ, Runge U, Witte OW, Stefan H, Hufnagel A, Mayer T, Krämer G. Substitution of anticonvulsant drugs. Ther Clin Risk Manag 2009; 5:449-57. [PMID: 19707254 PMCID: PMC2701486 DOI: 10.2147/tcrm.s5366] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Indexed: 11/23/2022] Open
Abstract
Changing from branded drugs to generic alternatives, or between different generic formulations, is common practice aiming at reducing health care costs. It has been suggested that antiepileptic drugs (AEDs) should be exempt from substitution because of the potential negative consequences of adverse events and breakthrough seizures. Controlled data are lacking on the risk of substitution. However, retrospective data from large medical claims databases suggest that switching might be associated with increased use of AED and non-AED medications, and health care resources (including hospitalization). In addition, some anecdotal evidence from patients and health care providers' surveys suggest a potentially negative impact of substitution. Well-controlled data are needed to assess the real risk associated with substitution, allowing health care professionals involved in the care of patients with epilepsy to make informed decisions. This paper reviews currently available literature, based on which the authors suggest that the decision to substitute should be made on an individual basis by the physician and an informed patient. Unendorsed or undisclosed substitution at the pharmacy level should be discouraged.
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Affiliation(s)
| | - Uwe Runge
- Department of Neurology, University of Greifswald, Greifswald, Germany
| | - Otto W Witte
- Department of Neurology, University of Jena, Jena, Germany
| | - Hermann Stefan
- Epilepsy Center, University of Erlangen, Erlangen, Germany
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Liow K. Understanding patients' perspective in the use of generic antiepileptic drugs: compelling lessons for physicians to improve physician/patient communication. BMC Neurol 2009; 9:11. [PMID: 19292903 PMCID: PMC2662789 DOI: 10.1186/1471-2377-9-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2008] [Accepted: 03/17/2009] [Indexed: 11/11/2022] Open
Abstract
Background Epilepsy is a condition in which consistency of treatment is paramount to successful management and for most patients, effective seizure control can be achieved. Given the severe consequences of even a single breakthrough seizure, patients should be afforded every opportunity to succeed on their given regimens. Discussion Some experts argue that global policy on generic antiepileptic drug substitution in epilepsy should be limited – occurring at the discretion of and with careful monitoring by the physician. While the debate continues, physicians still have daily responsibilities to their patients to help them best manage their epilepsy within the context of the current environment – the reality of which may involve switching to a generic antiepileptic drug or navigating various formulations between generics. Summary To provide context, this paper first reviews the main "hot button" issues fueling the ongoing generic debate, including a broad overview of the current state of the literature. The main goal however is to provide physicians with a patient perspective on generic antiepileptic drug use in epilepsy as a source of clinically useful, everyday advice to improve communication and increase patient self-advocacy, both of which are necessary for optimal patient outcome.
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Affiliation(s)
- Kore Liow
- Via Christi Comprehensive Epilepsy Center, University of Kansas School of Medicine at Wichita, 848 N St Francis, 3950 Wichita, KS 67214, USA.
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Gidal BE, Tomson T. Debate: Substitution of generic drugs in epilepsy: Is there cause for concern? Epilepsia 2008; 49 Suppl 9:56-62. [DOI: 10.1111/j.1528-1167.2008.01927.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Patsalos PN, Berry DJ, Bourgeois BFD, Cloyd JC, Glauser TA, Johannessen SI, Leppik IE, Tomson T, Perucca E. Antiepileptic drugs--best practice guidelines for therapeutic drug monitoring: a position paper by the subcommission on therapeutic drug monitoring, ILAE Commission on Therapeutic Strategies. Epilepsia 2008; 49:1239-76. [PMID: 18397299 DOI: 10.1111/j.1528-1167.2008.01561.x] [Citation(s) in RCA: 708] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Although no randomized studies have demonstrated a positive impact of therapeutic drug monitoring (TDM) on clinical outcome in epilepsy, evidence from nonrandomized studies and everyday clinical experience does indicate that measuring serum concentrations of old and new generation antiepileptic drugs (AEDs) can have a valuable role in guiding patient management provided that concentrations are measured with a clear indication and are interpreted critically, taking into account the whole clinical context. Situations in which AED measurements are most likely to be of benefit include (1) when a person has attained the desired clinical outcome, to establish an individual therapeutic concentration which can be used at subsequent times to assess potential causes for a change in drug response; (2) as an aid in the diagnosis of clinical toxicity; (3) to assess compliance, particularly in patients with uncontrolled seizures or breakthrough seizures; (4) to guide dosage adjustment in situations associated with increased pharmacokinetic variability (e.g., children, the elderly, patients with associated diseases, drug formulation changes); (5) when a potentially important pharmacokinetic change is anticipated (e.g., in pregnancy, or when an interacting drug is added or removed); (6) to guide dose adjustments for AEDs with dose-dependent pharmacokinetics, particularly phenytoin.
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Affiliation(s)
- Philip N Patsalos
- Institute of Neurology/The National Hospital for Neurology and Neurosurgery, London and The Chalfont Centre for Epilepsy, Chalfont St Peter, United Kingdom.
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Abstract
Therapeutic drug monitoring (TDM) of antiepileptic drugs (AEDs) has made it possible to study the individual variations in drug utilization, to reveal noncompliance in patients and for quality assurance aspects. Even if there is a shortage of data from randomized controlled studies concerning the effectiveness of using TDM as an aid to dosage adjustment, experience from nonrandomized investigations and long-lasting clinical experience have shown that TDM of both older and newer AEDs may be of clinical benefit if used appropriately. The main situations for TDM include: after starting treatment to provide a baseline steady-state concentration for further evaluation of an individual therapeutic concentration; after change in drug dosage, in particular when nonlinear kinetics apply; at therapeutic failure to sort out a pharmacokinetic explanation for uncontrolled seizures or side effects; in case of drug interactions; and when pharmacokinetic changes due to physiological or pathological changes are foreseen (e.g., age-dependent conditions [children, elderly], pregnancy, hepatic disease, renal disease or gastrointestinal conditions potentially affecting drug absorption) and change in drug formulation (brand name/generic). Recently, new terminology and definitions have been suggested by the International League Against Epilepsy. The reference range is a range of drug concentrations quoted by laboratories and is not a therapeutic range. Emphasis should be placed on the concept of an individual therapeutic concentration.
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Affiliation(s)
- Svein I Johannessen
- The National Center for Epilepsy, Sandvika, Division of Clinical Neuroscience, Rikshospitalet University Hospital, Oslo, POB 53, N-1306 BPT, Norway.
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Zachry WM, Doan QD, Clewell JD, Smith BJ. Case-control analysis of ambulance, emergency room, or inpatient hospital events for epilepsy and antiepileptic drug formulation changes. Epilepsia 2008; 50:493-500. [PMID: 18616554 DOI: 10.1111/j.1528-1167.2008.01703.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE Although antiepileptic drugs (AEDs) with multisource generic alternatives are becoming more prevalent, no case-control studies have been published examining multisource medication use and epilepsy-related outcomes. This study evaluated the association between inpatient/emergency epilepsy care and the occurrence of a recent switch in AED formulation. METHODS A case-control analysis was conducted utilizing the Ingenix LabRx Database. Eligible patients were 12-64 years of age, received >or=145 days of AEDs in the preindex period, had continuous eligibility for 6 months preindex, and no prior inpatient/emergency care. Cases received care between 7/1/2006 and 12/31/2006 in an ambulance, emergency room, or inpatient hospital with a primary epilepsy diagnosis. Controls had a primary epilepsy diagnosis in a physician's office during the same period. The index date was the earliest occurrence of care in each respective setting. Cases and controls were matched 1:3 by epilepsy diagnosis and age. Odds of a switch between "A-rated" AEDs within 6 months prior to index were calculated. RESULTS Cases (n = 416) had 81% greater odds of having had an A-rated AED formulation switch [odds ratio (OR) = 1.81; 95% confidence interval (CI) = 1.25 to 2.63] relative to controls (n = 1248). There were no significant differences between groups regarding demographics or diagnosis. Significant differences were found with regard to medical coverage type (case Medicaid = 4.6%, control Medicaid = 1.8%, p = 0.002). Post hoc analysis results excluding Medicaid recipients remained significant and concordant with the original analysis. DISCUSSION This analysis found an association between patients receiving epilepsy care in an emergency or inpatient setting and the recent occurrence of AED formulation switching involving A-rated generics.
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LeLorier J, Duh MS, Paradis PE, Latrémouille-Viau D, Lefebvre P, Manjunath R, Sheehy O. Economic impact of generic substitution of lamotrigine: projected costs in the US using findings in a Canadian setting. Curr Med Res Opin 2008; 24:1069-81. [PMID: 18315941 DOI: 10.1185/030079908x280572] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Generic substitution may not always save health care costs for antiepileptic drugs (AED). OBJECTIVE (1) To examine the economic impacts of generic substitution of lamotrigine in Canada; and (2) to convert observed Canadian costs to a United States (US) setting. METHODS Health claims from Québec's health plan (RAMQ) between 08/2002 and 07/2006 were analyzed. Patients with > or = 1 epilepsy claim and treated with branded lamotrigine (Lamictal) before generic entry were selected. Health care costs ($/person-year) were compared during periods of branded and generic use of lamotrigine. Two cost-conversion methods were employed; one using purchasing power parities, US/Canada service use ratios, and exchange rate, and another employing Canadian health care utilization and US unit costs. RESULTS 671 patients were observed during 1650.9 and 291.2 person-years of branded and generic use of lamotrigine, respectively. The generic-use period was associated with an increase in overall costs (2006 constant Canadian dollars) relative to brand use (C$7902 vs. C$6419/person-year; cost ratio (CR) = 1.22; p = 0.05), despite the lower cost of generic lamotrigine. Non-lamotrigine costs were 33% higher in the generic period (p = 0.013). Both conversion methods yielded increases in total projected health care costs excluding lamotrigine (2006 constant US dollars) during the generic period (Method 1: cost difference: US$1758/person-year, CR = 1.33, p = 0.01); Method 2: cost difference: US$2516, CR = 1.39, p = 0.004). LIMITATIONS Study limitations pertain to treatment differences, indicators used for conversion and possible claim inaccuracies. CONCLUSION Use of generic lamotrigine in Canada was significantly associated with increased overall medical costs compared to brand use. Projected overall US health care costs would likely increase as well.
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Affiliation(s)
- Jacques LeLorier
- Centre de recherche, Centre hospitalier de l'Université de Montréal, Québec, Canada
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Wolf P. Should newly diagnosed epilepsy be treated with generics? ACTA ACUST UNITED AC 2008; 4:176-7. [PMID: 18301412 DOI: 10.1038/ncpneuro0753] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Accepted: 01/22/2008] [Indexed: 11/10/2022]
Affiliation(s)
- Peter Wolf
- Copenhagen University Hospital, Copenhagen and at the Danish Epilepsy Centre, Dianalund, Denmark
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Surface-based texture and morphological analysis detects subtle cortical dysplasia. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2008; 11:645-52. [PMID: 18979801 DOI: 10.1007/978-3-540-85988-8_77] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Focal cortical dysplasia (FCD), a malformation of cortical development, is an important cause of pharmacoresistant epilepsy. Small FCD lesions are difficult to distinguish from normal cortex and remain often overlooked on radiological MRI inspection. This paper presents a method to detect small FCD lesions on T1-MRI relying on surface-based features that model their textural and morphometric characteristics. The automatic detection was performed by a two step classification. First, a vertex-wise classifier based on a neural-network bagging trained on manual labels. Then, a cluster-wise classification designed to remove false positive clusters. The method was tested on 19 patients with small FCD. At the first classification step, 18/19 (95%) lesions were detected. The second classification step kept 13/19 (68%) lesions and decreased efficiently the amount of false positive. This new approach may assist the presurgical evaluation of patients with intractable epilepsy, especially those with unremarkable MRI findings.
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