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Inoue Y, Tiamkao S, Zhou D, Cabral-Lim L, Lim KS, Lim SH, Tsai JJ, Moseley B, Wang L, Sun W, Hayakawa Y, Sasamoto H, Sano T, McClung C, Bass A. Efficacy, safety, and tolerability of adjunctive brivaracetam in adult Asian patients with uncontrolled focal-onset seizures: A phase III randomized, double-blind, placebo-controlled trial. Epilepsia Open 2024. [PMID: 38576178 DOI: 10.1002/epi4.12929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 03/04/2024] [Accepted: 03/07/2024] [Indexed: 04/06/2024] Open
Abstract
OBJECTIVE Evaluate efficacy, safety, and tolerability of adjunctive brivaracetam (BRV) in adult Asian patients with focal-onset seizures (FOS). METHODS Phase III, randomized, double-blind, placebo-controlled study (EP0083; NCT03083665) evaluating BRV 50 mg/day and 200 mg/day in patients (≥16-80 years) with FOS with/without secondary generalization (focal to bilateral tonic-clonic seizures) despite current treatment with 1 or 2 concomitant antiseizure medications. Following an 8-week baseline, patients were randomized 1:1:1 to placebo, BRV 50 mg/day, or BRV 200 mg/day, and entered a 12-week treatment period. Efficacy outcomes: percent reduction over placebo in 28-day FOS frequency (primary); 50% responder rate in FOS frequency; median percent reduction in FOS frequency from baseline; seizure freedom during treatment period (secondary). Primary safety endpoints: incidences of treatment-emergent adverse events (TEAEs); TEAEs leading to discontinuation; serious TEAEs. RESULTS In this study, 448/449 randomized patients (mean age, 34.5 years; 53.8% female) received ≥1 dose of study medication (placebo/BRV 50 mg/BRV 200 mg/day: n = 149/151/148). Percent reduction over placebo in 28-day adjusted FOS frequency was 24.5% (p = 0.0005) and 33.4% (p < 0.0001) with BRV 50 mg/day and 200 mg/day, respectively, 50% responder rate was 19.0%, 41.1%, and 49.3% with placebo, BRV 50 mg/day, and BRV 200 mg/day, respectively (p < 0.0001 for both BRV groups vs. placebo). Median percent reduction in FOS frequency from baseline was 21.3%/38.9%/46.7% in patients on placebo/BRV 50 mg/BRV 200 mg/day, respectively. Overall, 0, 7 (4.6%), and 10 (6.8%) patients were classified as seizure-free during the treatment period on placebo, BRV 50 mg/day, and BRV 200 mg/day, respectively (p = 0.0146/p = 0.0017 for BRV 50 mg/200 mg/day vs. placebo, respectively). TEAE incidences were similar between patients on placebo (58.4%) and all patients receiving BRV (58.5%); TEAE incidences for BRV 50 mg/day and BRV 200 mg/day were 57.0% and 60.1%, respectively. Overall, 0.7% of patients on placebo and 2.0% of all patients on BRV reported serious TEAEs (incidences for BRV 50 mg/day and BRV 200 mg/day were 1.3% and 2.7%, respectively), 20.1% of patients on placebo and 33.1% of all patients on BRV reported drug-related TEAEs (incidences for BRV 50 mg/day and BRV 200 mg/day were 26.5% and 39.9%, respectively), and 4.7% of patients on placebo and 3.0% of all patients on BRV discontinued due to TEAEs (discontinuation incidences for BRV 50 mg/day and BRV 200 mg/day were 2.6% and 3.4%, respectively). SIGNIFICANCE Adjunctive BRV was efficacious and well tolerated in adult Asian patients with FOS. Efficacy and safety profiles were consistent with BRV studies in predominantly non-Asian populations. PLAIN LANGUAGE SUMMARY Brivaracetam is used to treat partial or focal seizures in people with epilepsy. Most studies with brivaracetam tablets have involved people from non-Asian racial backgrounds. In this study, 449 Asian adults with epilepsy took part. One third took 50 mg of brivaracetam, one third took 200 mg of brivaracetam, and one third took a placebo each day for 12 weeks. On average, those who took brivaracetam had fewer seizures than those given the placebo. Most of the side effects were mild and the number and type of side effects seen were as expected for this medication.
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Affiliation(s)
- Yushi Inoue
- NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Shizuoka, Japan
| | - Somsak Tiamkao
- Integrated Epilepsy Research Group, Khon Kaen University, Srinagarind Hospital, Khon Kaen, Thailand
| | - Dong Zhou
- West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Leonor Cabral-Lim
- Department of Neurosciences, College of Medicine, Philippine General Hospital, University of the Philippines Manila, The Health Sciences Center, Manila, Philippines
| | - Kheng Seang Lim
- Division of Neurology, Department of Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Shih-Hui Lim
- Singapore General Hospital, Singapore City, Singapore
| | - Jing-Jane Tsai
- Department of Neurology, National Cheng Kung University Hospital, Tainan, Taiwan
| | | | | | | | | | | | | | | | - Almasa Bass
- UCB Pharma, Morrisville, North Carolina, USA
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Makedonska I, Ng YT, Beller C, Bozorg A, Csikós J, McClung C, Moeltgen H, Farkas MK. Efficacy and tolerability of adjunctive lacosamide in patients aged <4 years with focal seizures. Ann Clin Transl Neurol 2024; 11:768-779. [PMID: 38375995 DOI: 10.1002/acn3.52004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 11/29/2023] [Accepted: 12/26/2023] [Indexed: 02/21/2024] Open
Abstract
OBJECTIVE Primary objective was to evaluate efficacy of lacosamide administered concomitantly with 1-3 antiseizure medications in young children with uncontrolled focal (partial-onset) seizures. METHODS Double-blind, parallel-group trial (SP0967: NCT02477839/2013-000717-20) conducted between June 2015 and May 2020 at hospitals and clinics in 25 countries. Patients (aged ≥1 month to <4 years) with uncontrolled focal seizures were randomized 1:1 to adjunctive lacosamide or placebo using an interactive voice/web response system and stratified by age. After a 20-day titration period, patients who reached target-dose range (8-12 mg/kg/day) entered a 7-day maintenance period. Region-specific primary efficacy variables were based on ≤72-h video-electroencephalograms: change in average daily frequency (ADF) of electrographic focal seizures as measured on end-of-maintenance video-electroencephalogram versus end-of-baseline video-electroencephalogram (United States); 50% responder rate (≥50% reduction in ADF of focal seizures) during maintenance (European Union). RESULTS In total, 255 patients were randomized (lacosamide/placebo: 128/127) and received ≥1 trial medication dose. Percentage reduction in ADF of focal seizures for lacosamide (116 patients) versus placebo (120 patients) was 3.2% (95% confidence interval = -13.6 to 17.5, p = 0.69). 50% responder rate was 41.4% for lacosamide (116 patients), 37.5% for placebo (120 patients) (p = 0.58). Treatment-emergent adverse events were reported by 44.5% of lacosamide-treated patients (placebo 51.2%). INTERPRETATION Adjunctive lacosamide did not show superior efficacy versus placebo in young children with focal seizures. However, efficacy variables were potentially affected by high variability and low reliability between readers in video-electroencephalogram interpretation. Lacosamide was generally well tolerated; safety profile was acceptable and consistent with that in adults and children aged ≥4 years.
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Affiliation(s)
- Iryna Makedonska
- Municipal Non-profit Enterprise City Children's Clinical Hospital #6 of Dnipro City Council, Dnipro, Ukraine
| | - Yu-Tze Ng
- Baylor College of Medicine/The Children's Hospital of San Antonio, San Antonio, Texas, USA
| | | | - Ali Bozorg
- UCB Pharma, Morrisville, North Carolina, USA
| | | | | | | | - Mark Kristof Farkas
- Pediatric Center, MTA Center of Excellence, Semmelweis University, Budapest, Hungary
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Bozorg A, Beller C, Jensen L, Arzimanoglou A, Chiron C, Dlugos D, Gaitanis J, Wheless JW, McClung C. Pitfalls of using video-EEG for a trial endpoint in children aged <4 years with focal seizures. Ann Clin Transl Neurol 2024; 11:780-790. [PMID: 38318689 DOI: 10.1002/acn3.51999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 11/29/2023] [Accepted: 12/26/2023] [Indexed: 02/07/2024] Open
Abstract
OBJECTIVE Double-blind, randomized, and placebo-controlled trial SP0967 (NCT02477839/2013-000717-20) did not demonstrate superior efficacy of lacosamide versus placebo in patients aged ≥1 month to <4 years with uncontrolled focal seizures, per ≤72 h video-electroencephalogram (video-EEG)-based primary endpoints (reduction in average daily frequency of focal seizures at end-of-maintenance [EOM] versus end-of-baseline [EOB], patients with ≥50% response). This was unexpected because randomized controlled trial SP0969 (NCT01921205) showed efficacy of lacosamide in patients aged ≥4 to <17 years with uncontrolled focal seizures. SP0969's primary endpoint was based on seizure diary instead of video-EEG, an issue with the latter being inter-reader variability. We evaluated inter-reader agreement in video-EEG interpretation in SP0967, which to our knowledge, are the first such data for very young children with focal seizures from a placebo-controlled trial. METHODS Local investigator and central reader agreement in video-EEG interpretation was analyzed post hoc. RESULTS Analysis included 105 EOB and 98 EOM video-EEGs. Local investigators and central reader showed poor agreement based on ≥2 focal seizures at EOB (Kappa = 0.01), and fair agreement based on ≥2 focal seizures at EOM (Kappa = 0.23). Local investigator and central reader seizure count interpretations varied substantially, particularly for focal seizures, but also primary generalized and unclassified epileptic seizures, at both timepoints. INTERPRETATION High inter-reader variability and low inter-reader reliability of the interpretation of seizure types and counts prevent confident conclusion regarding the lack of efficacy of lacosamide in this population. We recommend studies in very young children do not employ video-EEGs exclusively for accurate study inclusion or as an efficacy measure.
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Affiliation(s)
- Ali Bozorg
- UCB Pharma, Morrisville, North Carolina, USA
| | | | - Lori Jensen
- UCB Pharma, Morrisville, North Carolina, USA
| | - Alexis Arzimanoglou
- Department of Paediatric Clinical Epileptology, Sleep Disorders and Functional Neurology, University Hospitals of Lyon (HCL), Member of the ERN EpiCARE, Lyon, France
- Epilepsy Unit, San Juan de Dios Children's Hospital, Member of the ERN EpiCARE, Universitat de Barcelona, Barcelona, Spain
| | | | - Dennis Dlugos
- Departments of Neurology and Pediatrics, Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - James W Wheless
- Le Bonheur Comprehensive Epilepsy Program & Neuroscience Institute, Le Bonheur Children's Hospital, University of Tennessee Health Science Center, Memphis, Tennessee, USA
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Farkas MK, Beller C, Bozorg A, McClung C, Roebling R, Yates T, Yuen N, Makedonska I. Safety and tolerability of short-term infusions of intravenous lacosamide in pediatric patients with epilepsy: An open-label, phase 2/3 trial. Epilepsia Open 2023; 8:146-153. [PMID: 36529709 PMCID: PMC9977742 DOI: 10.1002/epi4.12682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE The objective of this study is to evaluate the safety and tolerability of intravenous (IV) lacosamide infusion in patients aged ≥1 month to <17 years with epilepsy. METHODS This Phase 2/3 open-label trial (EP0060; NCT02710890) enrolled patients in two age cohorts (cohort 1: ≥8 to <17 years; cohort 2: ≥1 month to <8 years). Eligible patients were receiving oral lacosamide as adjunctive treatment or monotherapy (in an open-label long-term trial or by prescription) or were not receiving lacosamide before enrolment. Patients initiated IV lacosamide (2-12 mg/kg/day or 100-600 mg/day; 15-60 minutes infusion) as a replacement for oral lacosamide or as adjunctive treatment. The primary outcomes were treatment-emergent adverse events (TEAEs) and discontinuations due to TEAEs. RESULTS In total, 103 patients were enrolled and completed the trial; 55 patients were included in cohort 1 (≥8 to <17 years), 48 in cohort 2 (≥1 month to <8 years). During the 4 weeks before screening, 74 (71.8%) patients had focal seizures, 12 (11.7%) had generalized seizures, and two (1.9%) had unclassified seizures. Most patients (74 [71.8%]) initiated lacosamide as adjunctive IV treatment. The mean overall duration of exposure to IV lacosamide was 1.18 days. Seventy-nine (76.7%) patients had one IV lacosamide infusion, 20 (19.4%) had two, one (1.0%) had three, and three (2.9%) had 10 infusions. Overall, five (4.9%) patients had a total of seven TEAEs. The only TEAEs reported in two or more patients were increased blood triglycerides (two [1.9%]). No serious or severe TEAEs were reported, and no patients discontinued due to TEAEs. No TEAEs were considered drug-related by the investigator. No consistent or clinically relevant treatment-related changes from baseline were observed for hematology, clinical chemistry parameters, vital signs, or 12-lead electrocardiograms. SIGNIFICANCE IV lacosamide was generally well tolerated in pediatric patients (≥1 month to <17 years) with epilepsy, and no new safety concerns were identified.
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Affiliation(s)
| | | | - Ali Bozorg
- UCB Pharma, Morrisville, North Carolina, USA
| | | | | | | | - Nancy Yuen
- UCB Pharma, Morrisville, North Carolina, USA
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Sesno N, Ducusin A, Dunphy S, Hastings T, McClung C. 391 Routine Hatobiliary Iminodiacetic Acid Scan of All Suspected Cases of Acute Cholecystitis. Ann Emerg Med 2021. [DOI: 10.1016/j.annemergmed.2021.09.406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ben-Menachem E, Dominguez J, Szász J, Beller C, Howerton C, Jensen L, McClung C, Roebling R, Steiniger-Brach B. Long-term safety and tolerability of lacosamide monotherapy in patients with epilepsy: Results from a multicenter, open-label trial. Epilepsia Open 2021; 6:618-623. [PMID: 34265173 PMCID: PMC8408586 DOI: 10.1002/epi4.12522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 07/08/2021] [Accepted: 07/10/2021] [Indexed: 12/16/2022] Open
Abstract
The primary objective of this trial (SP1042; NCT02582866) was to assess long‐term safety and tolerability of lacosamide monotherapy (200‐600 mg/day) in adults with focal (partial‐onset) seizures or generalized tonic‐clonic seizures (without clear focal origin). This Phase III, long‐term, open‐label, multicenter, follow‐up trial enrolled patients with epilepsy who were taking lacosamide in, and completed, the previous double‐blind trial (SP0994; NCT01465997). Primary safety outcomes were treatment‐emergent adverse events (TEAEs), discontinuations due to TEAEs, and serious TEAEs. One hundred and six patients were enrolled and received lacosamide: 84 (79.2%) completed the trial and 22 (20.8%) discontinued. The median duration of exposure was 854.0 days, with a median modal dose of 200 mg/day. Ninety‐six (90.6%), 64 (60.4%), and 44 (41.5%) patients had ≥12, ≥24, and ≥36 months of lacosamide exposure, respectively. At least one TEAE was reported by 61 (57.5%) patients. The most common (≥4%) TEAEs were headache (10 [9.4%]), nasopharyngitis (eight [7.5%]), and back pain (five [4.7%]). One (0.9%) patient discontinued due to a TEAE (sudden unexpected death in epilepsy; not considered drug‐related), 14 (13.2%) patients reported serious TEAEs, and seven (6.6%) patients reported TEAEs that were considered drug‐related. Overall, long‐term lacosamide monotherapy was generally well tolerated up to 600 mg/day, with no new safety signals identified.
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Affiliation(s)
- Elinor Ben-Menachem
- Institute for Clinical Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Jacqueline Dominguez
- Institute for Neurosciences, St. Luke's Medical Center, Quezon City, Philippines
| | - József Szász
- George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureş, Emergency Clinical County Hospital Targu Mures (Spitalul Clinic Judeţean de Urgenţă Târgu Mureş), Sectia Clinica Neurologie II, Târgu Mureş, Romania
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Johnson ME, McClung C, Bozorg AM. Analyses of seizure responses supportive of a novel trial design to assess efficacy of antiepileptic drugs in infants and young children with epilepsy: Post hoc analyses of pediatric levetiracetam and lacosamide trials. Epilepsia Open 2021; 6:359-368. [PMID: 34033237 PMCID: PMC8166782 DOI: 10.1002/epi4.12482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 01/07/2021] [Accepted: 02/26/2021] [Indexed: 12/13/2022] Open
Abstract
Objective Recently, a novel trial design has been proposed to overcome challenges with traditional placebo‐controlled trials of antiepileptic drugs in infants and young children (≥1 month of age) (Auvin S, et al. Epilepsia Open 2019;4:537‐43). The proposed time‐to‐event trial design involves seizure counting by caregivers and allows adjustment of the duration of the baseline period and duration of exposure to placebo or potentially ineffective treatment based on the patient's seizure burden and response. We performed post hoc analyses to mimic this trial design and evaluate its viability. As these analyses required trials with prolonged baseline and treatment periods and diary data, which is not a typical design of trials in infants and young children (1 month to <4 years of age), data from two trials in pediatric patients (4‐16 years of age) were used. Methods We performed post hoc analyses of two randomized, double‐blind, placebo‐controlled trials of adjunctive levetiracetam (N159; NCT00615615) and lacosamide (SP0969; NCT01921205) in children and adolescents (4‐16 years of age) with focal‐onset seizures. In these analyses, patients were followed until they completed the 10‐week maintenance period, discontinued during the maintenance period, or reached their “nth” seizure (n = number of seizures patient had during baseline). Efficacy was assessed by determining time to nth seizure. Results In the analyses of both trials, patients on levetiracetam or lacosamide had a 34% lower risk of reaching their baseline seizure count during their 10‐week maintenance period than patients on placebo. The previously published primary results of these trials also demonstrated efficacy of adjunctive levetiracetam and lacosamide. Significance Although these were post hoc analyses of trials in older children (4‐16 years of age), our results provide supportive evidence for the utility of the novel time‐to‐event trial design for future trials in infants and young children (1 month to <4 years of age).
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Wu T, Chuang YC, Huang HC, Lim SN, Hsieh PF, Lee WT, Cheng MY, Tsai MH, Jou SB, Chang CW, Hsieh HY, Du X, Hellot S, McClung C, Hung C. A prospective, multicenter, noninterventional study in Taiwan to evaluate the safety and tolerability of lacosamide as adjunctive therapy for epilepsy in clinical practice. Epilepsy Behav 2020; 113:107464. [PMID: 33152580 DOI: 10.1016/j.yebeh.2020.107464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
RATIONALE Lacosamide (LCM) was initially approved in Taiwan in March 2014 for use as adjunctive therapy for focal impaired awareness seizures and secondarily generalized seizures (SGS) in patients with epilepsy ≥16 years of age. The efficacy and tolerability of adjunctive LCM for the treatment of patients with focal seizures have been demonstrated in randomized, placebo-controlled trials. However, the trials do not reflect a flexible dose setting. This study (EP0063) was conducted to assess the safety and tolerability of LCM in real-world clinical practice in Taiwan. Effectiveness of LCM was also assessed as an exploratory objective. METHODS EP0063 was a multicenter, prospective, noninterventional study with an expected observation period of 12 months ± 60 days. Eligible patients were ≥16 years of age, had focal impaired awareness seizures and/or SGS (in line with approved indication in Taiwan at the time of the study), were taking at least one concomitant antiseizure medication (ASM), and had at least one seizure in the 3 months before baseline. Patients were prescribed LCM by their treating physician in the course of routine clinical practice. The primary safety variable was treatment-emergent adverse events (TEAEs) spontaneously reported to, or observed by, the treating physician. Based on safety data from previous studies of LCM and known side effects of other ASMs, certain TEAEs (including but not limited to cardiac and electrocardiogram, suicidality, and rash related terms) were analyzed separately. Effectiveness variables included Clinical Global Impression of Change (CGIC) and change in 28-day seizure frequency from baseline to 12 months (or final visit), and freedom from focal seizures. RESULTS A total of 171 patients were treated with LCM, of whom 139 (81.3%) completed the study. The Kaplan-Meier estimated 12-month retention was 82.9%. Patients had a mean (standard deviation [SD], range) age of 38.5 (14.0, 16-77) years, and 96 (56.1%) were male. Patients were taking a mean (SD, range) of 2.8 (1.1, 1-6) ASMs at baseline. Mean (SD, range) duration of LCM treatment was 288.7 (111.9, 2-414) days, and the mean (SD, range) daily dosage of LCM was 205.0 (82.7, 50.0-505.2) mg/day. Overall, 95 (55.6%) patients reported at least one TEAE, most commonly dizziness (33 [19.3%] patients). Drug-related TEAEs were reported in 74 (43.3%) patients, and drug-related TEAEs leading to discontinuation of LCM were reported in 14 (8.2%) patients. Two (1.2%) patients died during LCM treatment, which were considered not related to LCM. Two (1.2%) patients had suicidality-related TEAEs; these TEAEs were considered either not related to LCM or the relationship was not recorded. Rash-related TEAEs were reported in five (2.9%) patients (considered LCM-related in two patients). Based on the CGIC, at 12 months (or final visit), 109 (63.7%) patients were considered to have improved, 54 (31.6%) had no change, and the remaining eight (4.7%) were minimally worse. At 12 months (or final visit), the median percentage change in focal seizure frequency was -50.0. During the first 6 months of the study, 21 (12.3%) patients were free from focal seizures; 37 (21.6%) patients were free from focal seizures in the last 6 months of the study; and 14 (8.2%) were free from focal seizures for the full 12 months of the study. CONCLUSIONS Results of this prospective, noninterventional study suggest that adjunctive LCM was generally safe and well tolerated in this patient group in real-world practice in Taiwan. Effectiveness was also favorable, with more than 60% of patients considered to be improved by their physician at 12 months (or final visit).
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Affiliation(s)
- Tony Wu
- Department of Neurology, Chang Gung Memorial Hospital, Linkou Branch, No. 5, Fuxing Street, Guishan District, Taoyuan 333, Taiwan; Department of Neurology, Xiamen Changgung Hospital, No. 123 Xiafei Road, Haicang District, Xiamen, China.
| | - Yao-Chung Chuang
- Department of Neurology, Chang Gung Memorial Hospital, Kaohsiung Branch, No. 123, Dapi Road, Niaosong District, Kaohsiung 833, Taiwan.
| | - Hui-Chun Huang
- Department of Neurology, China Medical University Hospital, No. 2, Yude Road, North District, Taichung 404, Taiwan
| | - Siew-Na Lim
- Department of Neurology, Chang Gung Memorial Hospital, Linkou Branch, No. 5, Fuxing Street, Guishan District, Taoyuan 333, Taiwan
| | - Peiyuan F Hsieh
- Neurological Institute, Division of Epilepsy, Taichung Veterans General Hospital, No. 1650, Section 4, Taiwan Boulevard, Xitun District, Taichung 407, Taiwan.
| | - Wang-Tso Lee
- Department of Pediatrics, National Taiwan University Hospital, No. 7, Zhongshan South Road, Zhongzheng District, Taipei 100, Taiwan
| | - Mei-Yun Cheng
- Department of Neurology, Chang Gung Memorial Hospital, Linkou Branch, No. 5, Fuxing Street, Guishan District, Taoyuan 333, Taiwan
| | - Meng-Han Tsai
- Department of Neurology, Chang Gung Memorial Hospital, Kaohsiung Branch, No. 123, Dapi Road, Niaosong District, Kaohsiung 833, Taiwan.
| | - Shuo-Bin Jou
- Department of Neurology, MacKay Memorial Hospital, No. 92, Section 2, Zhongshan North Road, Zhongshan District, Taipei 104, Taiwan
| | - Chun-Wei Chang
- Department of Neurology, Chang Gung Memorial Hospital, Linkou Branch, No. 5, Fuxing Street, Guishan District, Taoyuan 333, Taiwan
| | - Hsiang-Yao Hsieh
- Department of Neurology, Chang Gung Memorial Hospital, Linkou Branch, No. 5, Fuxing Street, Guishan District, Taoyuan 333, Taiwan.
| | - Xinlu Du
- UCB Pharma, 14 Taikoo Wan Road, Taikoo, Hong Kong, China
| | - Scarlett Hellot
- UCB Pharma, Alfred-Nobel-Straße 10, 40789 Monheim am Rhein, Germany.
| | - Carrie McClung
- UCB Pharma, 8010 Arco Corporate Drive, Raleigh, NC 27617, USA.
| | - Connie Hung
- UCB Pharma, 12th Floor-2, No.88, Dunhua North Road, Songshan District, Taipei 10551, Taiwan.
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Chon H, Kang S, Lee J, Gonzalez-Bosquet J, Wenham R, McClung C, Abdallah R. Gene expression signature based prediction of lymph node metastasis in patients with endometrioid endometrial cancer. Gynecol Oncol 2017. [DOI: 10.1016/j.ygyno.2017.03.303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Clements M, Roscoe L, McClung C, Wenham R, Shahzad M. Bald and beautiful? Quality of life and chemotherapy-induced alopecia. Gynecol Oncol 2017. [DOI: 10.1016/j.ygyno.2017.03.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Craig J, Broghammer J, Kaufman M, Milam D, Cleves M, McClung C, Brady J, Jones L, Gross M, Henry G, Brant W. 011 Outcomes after AUS Replacement due to Cuff Erosion: Results from a Multicenter Retrospective Analysis. J Sex Med 2017. [DOI: 10.1016/j.jsxm.2016.12.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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McClung C, Berglund A, Welsh E, Xiong Y, Bush S, Robertson S, Chon H, Magliocco A, Marchion D, Apte S. Gene expression profiling of 389 endometrioid endometrial carcinomas reveals 4 distinct molecular subtypes. Gynecol Oncol 2016. [DOI: 10.1016/j.ygyno.2016.04.498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Boac B, Xiong Y, Marchion D, Abbasi F, Khulpateea B, McClung C, Robertson S, Lancaster J, Magliocco A. Micro-RNAs associated with ovarian cancer in vitro cisplatin resistance regulate epithelial-mesenchymal transition. Gynecol Oncol 2016. [DOI: 10.1016/j.ygyno.2016.04.141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Robertson S, Marchion D, McClung C, Whynott R, Abbasi F, Xiong Y, Tomassino M, Magliocco A, Giuliano A, Shahzad M. The prevalence of viral DNA in epithelial ovarian cancer and correlation with clinical outcomes. Gynecol Oncol 2016. [DOI: 10.1016/j.ygyno.2016.04.195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Khulpateea B, Marchion D, Xiong Y, Boac B, Abbasi F, McClung C, Judson P, Apte S, Wenham R, Lancaster J. Molecular signaling pathways associated with squamous-cell carcinoma of the cervix cisplatin-resistance. Gynecol Oncol 2015. [DOI: 10.1016/j.ygyno.2015.01.183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Al Sawah E, Xiong Y, Boac B, Abbasi F, Marchion D, Ramirez I, Bush S, McClung C, Judson Lancaster P, Lancaster J. AKT survival signaling as a determinant of ovarian cancer chemoresistance and clinical outcome. Gynecol Oncol 2015. [DOI: 10.1016/j.ygyno.2015.01.439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Ramirez I, Marchion D, Xiong Y, Abbasi F, Boac B, McClung C, Al Sawah E, Judson P, Apte S, Lancaster J. Repurposing Artesunate, an anti-malarial, for ovarian cancer treatment: Mechanistic insights from cell line models. Gynecol Oncol 2015. [DOI: 10.1016/j.ygyno.2015.01.520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Previs RA, Bevis KS, Huh W, Tillmanns T, Perry L, Moore K, Chapman J, McClung C, Kiet T, Java J, Chan J, Secord AA. A prognostic nomogram to predict overall survival in women with recurrent ovarian cancer treated with bevacizumab and chemotherapy. Gynecol Oncol 2014; 132:531-6. [PMID: 24472410 DOI: 10.1016/j.ygyno.2014.01.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 01/10/2014] [Accepted: 01/20/2014] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To develop a nomogram to predict overall survival (OS) in women with recurrent ovarian cancer treated with bevacizumab and chemotherapy. METHODS A multicenter retrospective study was conducted. Potential prognostic variables included age; stage; grade; histology; performance status; residual disease; presence of ascites and/or pleural effusions; number of chemotherapy regimens, treatment-free interval (TFI) prior to bevacizumab administration, and platinum sensitivity. Multivariate analysis was performed using Cox proportional hazards regression. The predictive model was developed into a nomogram to predict five-year OS. RESULTS 312 women with recurrent ovarian cancer treated with bevacizumab and chemotherapy were identified; median age was 59 (range: 19-85); 86% women had advanced stage (III-IV) disease. The majority had serous histology (74%), high grade cancers (93.5%), and optimal cytoreductions (69.5%). Fifty-one percent of women received greater than two prior chemotherapeutic regimens. TFI (AHR=0.98, 95% CI 0.97-1.00, p=0.022) was the only statistically significant predictor in a multivariate progression-free survival (PFS) analysis. In a multivariate OS analysis, prior number of chemotherapy regimens, TFI, platinum sensitivity, and presence of ascites were significant. A nomogram to predict five-year OS was constructed and internally validated (bootstrap-corrected concordance index=0.737). CONCLUSION Our multivariate model identified prior number of chemotherapy regimens, TFI, platinum sensitivity, and the presence of ascites as prognostic variables for OS in women with recurrent ovarian cancer treated with bevacizumab combined with chemotherapy. Our nomogram to predict five-year OS may be used to identify women who may benefit from bevacizumab and chemotherapy, but further validation is needed.
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Affiliation(s)
- R A Previs
- Duke University Medical Center, Durham, NC, USA.
| | - K S Bevis
- University of Alabama at Birmingham, Birmingham, AL, USA
| | - W Huh
- University of Alabama at Birmingham, Birmingham, AL, USA
| | - T Tillmanns
- West Clinic and University of Tennessee Health Science Center, Memphis, TN, USA
| | - L Perry
- Stevenson Oklahoma Cancer Center at the University of Oklahoma, Oklahoma City, OK, USA
| | - K Moore
- Stevenson Oklahoma Cancer Center at the University of Oklahoma, Oklahoma City, OK, USA
| | - J Chapman
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA; Stanford Women's Cancer Center, Stanford Hospital and Clinics, Palo Alto, CA, USA
| | - C McClung
- Stanford Women's Cancer Center, Stanford Hospital and Clinics, Palo Alto, CA, USA
| | - T Kiet
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA
| | - J Java
- Gynecologic Oncology Group Statistical and Data Center, Roswell Park Cancer Institute, Buffalo, New York, USA
| | - J Chan
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA
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Harden RN, Freeman R, Rainka M, Zhang L, Bell C, Berges A, Chen C, Graff O, Harding K, Hunter S, Kavanagh S, Schwartzbach C, Warren S, McClung C. A phase 2a, randomized, crossover trial of gabapentin enacarbil for the treatment of postherpetic neuralgia in gabapentin inadequate responders. Pain Med 2013; 14:1918-32. [PMID: 24102928 DOI: 10.1111/pme.12227] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE To compare the efficacy of high-dose (3,600 mg/day) vs low-dose (1,200 mg/day) oral gabapentin enacarbil (GEn) on pain intensity in adults with postherpetic neuralgia (PHN) and a history of inadequate response to ≥1,800 mg/day gabapentin. DESIGN Multicenter, randomized, double-blind, crossover study (NCT00617461). SETTING Thirty-five outpatient centers in Germany and the United States. SUBJECTS Subjects aged ≥18 years with a diagnosis of PHN. METHODS During a 2-week baseline period, subjects received open-label treatment with 1,800 mg/day gabapentin. Subjects who had a mean 24-hour average pain intensity score ≥4 during the last 7 days of the baseline period were randomized to receive GEn (1,200 or 3,600 mg/day) for treatment period 1 (28 days), followed by GEn 2,400 mg/day (4 days), and the alternate GEn dose for treatment period 2 (28 days). RESULTS There was a modest but significant improvement in pain intensity scores with GEn 3,600 mg vs 1,200 mg (adjusted mean [90% confidence interval] treatment difference, -0.29 [-0.48 to -0.10]; P = 0.013). The difference in efficacy between doses was observed primarily in subjects who received the higher dose during treatment period 2; certain aspects of the study design may have contributed to this outcome. Plasma steady-state gabapentin exposure during GEn treatment was as expected and consistent between treatment periods. No new safety signals or adverse event trends relating to GEn exposure were identified. CONCLUSIONS While the overall results demonstrated efficacy in a PHN population, the differences between treatment periods confound the interpretation. These findings could provide insight into future trial designs.
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Zhang L, Rainka M, Freeman R, Harden RN, Bell CF, Chen C, Graff O, Harding K, Hunter S, Kavanagh S, Laurijssens B, Schwartzbach C, Warren S, McClung C. A randomized, double-blind, placebo-controlled trial to assess the efficacy and safety of gabapentin enacarbil in subjects with neuropathic pain associated with postherpetic neuralgia (PXN110748). J Pain 2013; 14:590-603. [PMID: 23602345 DOI: 10.1016/j.jpain.2013.01.768] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 01/11/2013] [Accepted: 01/19/2013] [Indexed: 02/07/2023]
Abstract
UNLABELLED Gabapentin enacarbil (GEn) is an actively transported prodrug of gabapentin that provides sustained, dose-proportional exposure to gabapentin. This randomized, double-blind, parallel-group, placebo-controlled study evaluated the safety and efficacy of 3 different maintenance doses of oral GEn in subjects with postherpetic neuralgia. Adults with a 24-hour average pain intensity score of ≥4.0 received GEn 1,200 mg, 2,400 mg, 3,600 mg, or placebo for 14 weeks (including a 1-week up-titration, 12-week maintenance, and 1-week taper). The primary endpoint was change from baseline to end of maintenance treatment in mean 24-hour average pain intensity score. The intent-to-treat population consisted of 371 subjects (GEn 1,200 mg = 107, 2,400 mg = 82, 3,600 mg = 87, placebo = 95). With regard to the primary endpoint, all 3 GEn treatment groups demonstrated a statistically significant difference relative to placebo. The adjusted mean change from baseline for the treatment groups ranged from -2.36 to -2.72 versus -1.66 for the placebo group. Exposure-response modeling suggested an ED50 around 1,200 mg/day, which was consistent with historical findings reported for gabapentin. The most commonly reported adverse events were dizziness and somnolence. All studied doses of GEn significantly improved pain associated with postherpetic neuralgia as compared to placebo and were well tolerated. PERSPECTIVE GEn provides clinically important pain relief with doses from 1,200 mg to 3,600 mg and is generally well tolerated and efficacious. As an actively transported prodrug of gabapentin, it provides dose-proportional and extended exposure to gabapentin.
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Affiliation(s)
- Lixin Zhang
- Dent Neurologic Institute, Amherst, New York, USA
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Chan J, Alvarez-Secord A, Tillmanns T, Moore K, Bevis K, ElNaggar A, Perry L, McClung C, Tian C, Huh W. Outcomes of ovarian cancer patients after bevacizumab and chemotherapy in primary vs. recurrent setting – A multi-institutional study. Gynecol Oncol 2012. [DOI: 10.1016/j.ygyno.2011.12.236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Alvarez-Secord A, Huh W, Tillmanns T, Moore K, Chapman J, McClung C, Kiet T, Kattan M, Java J, Chan J. Prognostic factors predictive of response to bevacizumab combined with chemotherapy in recurrent ovarian cancer – A multi-institutional study. Gynecol Oncol 2012. [DOI: 10.1016/j.ygyno.2011.12.235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Foster R, Jung J, Farooq A, McClung C, Ripsch MS, Fitzgerald MP, White FA. Sciatic nerve injury induces functional pro-nociceptive chemokine receptors in bladder-associated primary afferent neurons in the rat. Neuroscience 2011; 183:230-7. [PMID: 21458542 PMCID: PMC3219924 DOI: 10.1016/j.neuroscience.2011.03.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 03/18/2011] [Accepted: 03/19/2011] [Indexed: 02/06/2023]
Abstract
Visceral sensory afferents during disease or following injury often produce vague, diffuse body sensations, and pain referred to somatic targets. Alternatively, injury due to trauma or disease of somatic nerve targets can also lead to referred pain in visceral targets via a somatovisceral reflex. Both phenomenons are thought to be due to convergence of visceral and somatic afferents within the spinal cord. To investigate a potential peripheral influence for referred pain in visceral targets following somatic nerve injury, we examined whether a sciatic nerve injury known to produce hindpaw tactile hyperalgesia alters the frequency of micturition and the sensitivity of bladder-associated sensory neurons to pro-nociceptive chemokines. Adult female Sprague-Dawley rats received injections of cholera toxin B subunit conjugated to 555 into urinary bladder wall to retrogradely label visceral primary afferent neurons. After 7 days, the right sciatic nerve of these animals was subjected to a lysophosphatidylcholine (LPC)-induced focal demyelination injury. Pre- and post-injury tactile sensitivity in the hind paw and micturition frequency were assayed. Animals were allowed to survive for 14-28 days. Lumbosacral and lumbar dorsal root ganglia (DRG) ipsilateral to the nerve injury were acutely dissociated from sham and nerve injured animals. Bladder wall-associated sensory neurons identified via the retrograde marker were assayed for fluxes in intracellular calcium following administration of pro-nociceptive chemokines. The assayed chemokines included monocyte chemoattractant protein-1 (MCP1/CCL2) and stromal cell derived factor-1 alpha (SDF1/CXCL12). LPC nerve injured animals exhibited tactile hyperalgesia and increased micturition frequency for at least 28 days. Focal demyelination of the sciatic nerve also increased the number of injured L₄L₅ and non-injured L₆-S₂ bladder-associated sensory neurons that responded to MCP1 and SDF1 when compared with sensory neurons derived from uninjured naïve and sham-injured control animals. Taken together, these data suggest that some visceral hypersensitivity states may have a somatic origin. More importantly, nociceptive somatovisceral sensation may be mediated by upregulation of chemokine signaling in visceral sensory neurons.
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Affiliation(s)
- R Foster
- Department of Urology, Loyola University Health System, Maywood, IL, USA
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Bezard E, Berton O, Guigoni C, Dovero S, Kumar A, McClung C, DiLeone R, Nestler E. 2.501 Role of DeltaFosB in the development of L-DOPA-induced dyskinesia in a non-human primate model of Parkinson's disease. Parkinsonism Relat Disord 2007. [DOI: 10.1016/s1353-8020(08)70775-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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McClung C, Schroeder K, Wan T, Henderson S. 46. Ann Emerg Med 2006. [DOI: 10.1016/j.annemergmed.2006.07.494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Baffa R, Letko J, McClung C, LeNoir J, Vecchione A, Gomella LG. Molecular genetics of bladder cancer: targets for diagnosis and therapy. J Exp Clin Cancer Res 2006; 25:145-60. [PMID: 16918124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Transitional cell carcinoma of the bladder is a common tumor. While most patients presenting superficial disease can be expected to do well following treatment, still many patients will return to our office with muscle invasive and metastatic disease. Survival in advanced bladder cancer is less than 50%. Tumors of similar histologic grade and stage have variable behavior, suggesting that genetic alterations must be present to explain the diverse behavior of bladder cancer. It is hoped that through the study of the subtle genetic alterations in bladder cancer, important prognostic and therapeutic targets can be exploited. Many new diagnostic tests and gene therapy approaches rely on the identification and targeting of these unique genetic alterations. A review of literature published on the molecular genetics of bladder cancer from 1970 to the present was conducted. A variety of molecular genetic alterations have been identified in bladder cancer. Oncogenes (H-ras, erbB-2, EGFR, MDM2, C-MYC, CCND1), tumor suppressor genes (p53, Rb, p21, p27/KIP1, p16, PTEN, STK15, FHIT, FEZ1/LZTS1, bc10), telomerase, and methylation have all been studied in bladder cancer. Several have proven to be potentially useful clinical targets in the prognosis and therapy of bladder cancer such as staining for p53 and gene therapy strategies such as p53 and fez1. Clinical trials targeting HER2/neu and the EGFR pathways are underway. The UroVysion bladder cancer assay relies on FISH to detect genetic alterations in this disease. Continuing identification of the molecular genetic alterations in bladder cancer will enhance future diagnostic and therapeutic approaches to bladder cancer. Capitalizing on these alterations will allow early detection, providing important prognostic information and unique targets for gene therapy and other therapeutic approaches.
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Affiliation(s)
- R Baffa
- Department of Urology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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Abstract
BACKGROUND Sensitization to psychostimulant drugs of abuse is thought to be an important aspect of human addiction, yet how it develops is still unclear. The development of sensitization to cocaine in the fruit fly Drosophila melanogaster is strikingly similar to that observed in vertebrates. By taking advantage of the powerful genetic approaches that are possible in Drosophila, we are able to identify and characterize mutants that fail to develop sensitization. RESULTS We found that the Drosophila mutant inactive (iav) failed to become sensitized to cocaine. Mutant flies had reduced amounts of the trace amine tyramine in the brain because of reduced activity of the enzyme tyrosine decarboxylase (TDC), which converts tyrosine to tyramine. Furthermore, cocaine exposure induced TDC enzyme activity in a time-dependent manner that paralleled the development of behavioral sensitization. The sensitization failure of iav flies could be rescued by feeding the flies with tyramine; other biogenic amines or amine precursors did not have the same effect. CONCLUSIONS These results indicate an essential role for tyramine in cocaine sensitization in Drosophila.
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Affiliation(s)
- C McClung
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903, USA
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Abstract
Cocaine abuse is a large social and economic problem that has received much public and scientific attention in recent years. Rodent and primate models have been used to study the behavioral and neurological effects of cocaine. Repeated intermittent doses of cocaine lead to progressive increases in both locomotor activity and stereotyped behaviors known as 'reverse tolerance' or behavioral sensitization, which may model the behavioral and neurochemical processes occurring in cocaine-addicted humans [1]. The biological basis of sensitization is poorly understood. We report that free-base cocaine administered in volatile form to the fruit fly Drosophila melanogaster induces multiple reflexive motor responses that resemble cocaine-induced behaviors in rodents. These behaviors are both dose dependent and sexually dimorphic. Furthermore, Drosophila develops a behavioral sensitization to intermittent doses of cocaine. These results suggest that the pathways leading to cocaine-induced responses and sensitization are evolutionarily conserved between Drosophila and higher vertebrates, and that this genetically tractable animal can be used as a new model system to help determine the biological mechanisms underlying these processes.
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Affiliation(s)
- C McClung
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903, USA
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