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1.
Blood Adv ; 8(10): 2552-2564, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38537079

RESUMO

ABSTRACT: Malaria is a highly oxidative parasitic disease in which anemia is the most common clinical symptom. A major contributor to the malarial anemia pathogenesis is the destruction of bystander, uninfected red blood cells (RBCs). Metabolic fluctuations are known to occur in the plasma of individuals with acute malaria, emphasizing the role of metabolic changes in disease progression and severity. Here, we report conditioned medium from Plasmodium falciparum culture induces oxidative stress in uninfected, catalase-depleted RBCs. As cell-permeable precursors to glutathione, we demonstrate the benefit of pre-exposure to exogenous glutamine, cysteine, and glycine amino acids for RBCs. Importantly, this pretreatment intrinsically prepares RBCs to mitigate oxidative stress.


Assuntos
Aminoácidos , Eritrócitos , Estresse Oxidativo , Plasmodium falciparum , Plasmodium falciparum/efeitos dos fármacos , Eritrócitos/parasitologia , Eritrócitos/metabolismo , Eritrócitos/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos , Aminoácidos/metabolismo , Malária Falciparum/prevenção & controle , Malária Falciparum/parasitologia
2.
bioRxiv ; 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37292635

RESUMO

Malaria is a highly oxidative parasitic disease in which anemia is the most common clinical symptom. A major contributor to malarial anemia pathogenesis is the destruction of bystander, uninfected red blood cells. Metabolic fluctuations are known to occur in the plasma of individuals with acute malaria, emphasizing the role of metabolic changes in disease progression and severity. Here, we report that conditioned media from Plasmodium falciparum culture induces oxidative stress in healthy uninfected RBCs. Additionally, we show the benefit of amino acid pre-exposure for RBCs and how this pre-treatment intrinsically prepares RBCs to mitigate oxidative stress. Key points: Intracellular ROS is acquired in red blood cells incubated with Plasmodium falciparum conditioned media Glutamine, cysteine, and glycine amino acid supplementation increased glutathione biosynthesis and reduced ROS levels in stressed RBCs.

3.
Curr Protoc ; 2(3): e400, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35349226

RESUMO

The bone microenvironment cellular composition plays an essential role in bone health and is disrupted in bone pathologies, such as osteoporosis, osteoarthritis, and cancer. Flow cytometry protocols for hematopoietic stem cell lineages are well defined and well established. Additionally, a consensus for mesenchymal stem cell flow markers has been developed. However, flow cytometry markers for bone-residing cells-osteoblasts, osteoclasts, and osteocytes-have not been proposed. Here, we describe a novel partial digestion method to separate these cells from the bone matrix and present new markers for enumerating these cells by flow cytometry. We optimized bone digestion and analyzed markers across murine, nonhuman primate, and human bone. The isolation and staining protocols can be used with either cell sorting or flow cytometry. Our method allows for the enumeration and collection of hematopoietic and mesenchymal lineage cells in the bone microenvironment combined with bone-residing stromal cells. Thus, we have established a multi-fluorochrome bone marrow cell-typing methodology. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Partial digestion for murine long bone stromal cell isolation Alternate Protocol 1: Partial digestion for primate vertebrae stromal cell isolation Alternate Protocol 2: Murine vertebrae crushing for bone stromal cell isolation Basic Protocol 2: Staining of bone stromal cells Support Protocol 1: Fluorescence minus one control, isotype control, and antibody titration Basic Protocol 3: Cell sorting of bone stromal cells Alternate Protocol 3: Flow cytometry analysis of bone stromal cells Support Protocol 2: Preparing compensation beads.


Assuntos
Células da Medula Óssea , Células Estromais , Animais , Medula Óssea , Separação Celular/métodos , Citometria de Fluxo/métodos , Camundongos
4.
Epilepsy Behav ; 103(Pt A): 106864, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31937513

RESUMO

OBJECTIVE: The objective of this analysis was to provide a comprehensive analysis of safety data for adjunctive brivaracetam (BRV), an antiepileptic drug (AED) of the racetam class, for treatment of focal seizures in patients with epilepsy. METHODS: Data were pooled from two phase II, placebo-controlled, double-blind, dose-ranging trials (N01114 [ClinicalTrials.gov: NCT00175929], N01193 [NCT00175825]) and three phase III, placebo-controlled, double-blind, 12-week trials (N01252 [NCT00490035], N01253 [NCT00464269], and N01358 [NCT01261325]) in patients aged ≥16 years with focal seizures, as well as a phase III, placebo-controlled, double-blind, 16-week trial in patients aged ≥16 years with focal or generalized epilepsy (N01254 [NCT00504881]). Data are presented for the approved therapeutic dose range of 50-200 mg/day. Data for BRV administered intravenously (25-150 mg doses) were pooled separately from one phase III trial (N01258 NCT01405508]) and two clinical pharmacology trials (N01256 [Part B] [UCB Pharma, data on file]; EP0007 [NCT01796899]). Adverse events (AEs) of interest were summarized in relevant categories. RESULTS: The safety pool comprised 1957 patients: 1271 receiving adjunctive BRV and 686 receiving placebo. Overall, the incidence of treatment-emergent adverse events (TEAEs) was 66.9% with BRV versus 62.8% with placebo. The most frequently reported TEAEs with BRV (≥5% of patients) versus placebo were somnolence (13.3% vs. 7.9%), headache (10.5% vs. 11.5%), dizziness (10.0% vs. 7.0%), and fatigue (8.2% vs. 4.2%). Incidence of psychiatric disorder-related TEAEs was 11.3% with BRV versus 8.2% with placebo. Behavioral disorder-related TEAE incidence was low (4.0% with BRV vs. 2.5% with placebo). Irritability was reported in 2.7% of BRV-treated patients vs. 1.5% of patients receiving placebo; anger, aggression, and agitation were each reported by ≤1% of patients receiving BRV. Treatment-emergent adverse events potentially associated with psychosis were psychotic disorder (three patients on BRV vs. two patients on placebo), auditory hallucination, illusion, visual hallucination (one patient each on BRV), epileptic psychosis, and hallucination (one patient each on placebo). No additional safety concerns were identified in patients with intravenous (IV) BRV administration (n = 104). CONCLUSIONS: These safety data for adjunctive BRV support its acceptable safety and tolerability profile.


Assuntos
Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Epilepsia/tratamento farmacológico , Pirrolidinonas/administração & dosagem , Pirrolidinonas/efeitos adversos , Administração Intravenosa , Ensaios Clínicos Fase II como Assunto/métodos , Ensaios Clínicos Fase III como Assunto/métodos , Tontura/induzido quimicamente , Método Duplo-Cego , Quimioterapia Combinada , Epilepsia/diagnóstico , Fadiga/induzido quimicamente , Humanos , Resultado do Tratamento
5.
Epilepsy Res ; 145: 55-62, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29908435

RESUMO

To assess the association, if any, between brivaracetam (BRV)-induced elevated carbamazepine-10,11-epoxide (CBZ-E) and toxicity and efficacy in patients with epilepsy. Data were pooled from three double-blind, placebo-controlled, Phase III studies of adjunctive BRV in adults with uncontrolled focal seizures (N01252/NCT00490035, N01253/NCT00464269, N01358/NCT01261325). Treatment-emergent adverse events (TEAEs) of interest (ataxia, diplopia, dizziness, nystagmus, somnolence, accidental overdose or poisoning, and toxicity), discontinuations due to TEAEs, and serious TEAEs (SAEs) were assessed in subgroups who did/did not receive carbamazepine (CBZ) at study entry (CBZ+ and CBZ-). Logistic regression analysis evaluated CBZ-E/CBZ plasma concentrations and TEAEs. SAEs suggestive of CBZ-E toxicity were summarized from the BRV safety database up to a cut-off of October 1, 2014. Percent reduction in focal seizure frequency over placebo was assessed in subgroups of CBZ-E/CBZ ratios. Data from 1558 patients were included in the pooled safety population. Of these, concomitant CBZ was received by 184/459 (40.1%) placebo-treated and 315/803 (39.2%) BRV-treated patients (≥50 mg/day). In BRV-treated patients, study completion rates were similar in the CBZ+ (92.7%) and CBZ- (88.7%) groups; incidence of TEAEs of interest was similar (CBZ+ 24.4%; CBZ- 24.2%), and did not appear affected by CBZ dosage; SAEs and discontinuations due to TEAEs were CBZ+ 1.6%; CBZ- 3.9% and 2.9%; 9.2%, respectively. Likelihood of TEAEs of interest decreased with increasing CBZ-E/CBZ ratio for BRV-treated patients: odds ratio 0.88 (95% confidence intervals 0.74, 1.03; p = 0.112). In the safety database, five SAEs suggestive of CBZ-E toxicity were identified. Efficacy outcomes did not appear to have a consistent pattern across CBZ-E/CBZ ratio subgroups. This post-hoc analysis does not support an association between CBZ-E levels and TEAEs potentially associated with CBZ-E toxicity, or with increases in efficacy. Overall, current evidence does not suggest that BRV dose adjustment is required with concomitant CBZ.


Assuntos
Anticonvulsivantes/uso terapêutico , Carbamazepina/uso terapêutico , Epilepsia/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Adolescente , Adulto , Idoso , Anticonvulsivantes/sangue , Área Sob a Curva , Carbamazepina/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Sinergismo Farmacológico , Epilepsia/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pirrolidinonas/sangue , Adulto Jovem
6.
Epilepsy Res ; 141: 73-82, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29486396

RESUMO

Brivaracetam (BRV), a selective, high-affinity ligand for synaptic vesicle protein 2A, is a new antiepileptic drug (AED) approved for monotherapy (in the USA) and adjunctive treatment of focal (partial-onset) seizures in adults, at a dose range of 50-200 mg/day taken in two equal doses, with a recommended starting dose of 100 mg/day. Two Phase III, randomized, double-blind, multicenter, historical-controlled, conversion-to-monotherapy studies (N01276, NCT00698581; N01306, NCT00699283) were conducted to evaluate the efficacy, safety, and tolerability of conversion to BRV 50 mg/day monotherapy in adults with uncontrolled focal seizures. Patients aged 16-75 years, with 2-40 focal seizures per 4 weeks during an 8-week baseline, and on stable doses of 1-2 AEDs were enrolled. Patients were randomized to BRV 50 or 100 mg/day (3:1) in two equal doses without titration. The treatment period comprised 1-week BRV add-on, 8-week baseline AED tapering, and 8-week BRV monotherapy periods. Primary efficacy endpoint was Kaplan-Meier estimate of the cumulative exit rate due to pre-defined exit criteria at Day 112 (50 mg/day, efficacy population). The upper 95% confidence interval (CI) was compared with the historical control threshold (0.722). Safety and tolerability assessments included treatment-emergent adverse events (TEAEs; intent-to-treat population). After randomization of 150 patients (N01276: 88; N01306: 62), both studies were terminated due to the confounding effects of a higher-than-expected discontinuation rate. For BRV 50 mg/day, ≥1 exit criterion was met by 26/67 (38.8%) patients (study N01276) and 18/45 (40.0%) patients (study N01306). In both studies, the cumulative exit rate was lower than the historical control threshold (N01276: 0.487, 95% CI 0.347, 0.626; N01306: 0.474, 95% CI 0.310, 0.638). However, with maximum 10% censoring due to early withdrawal (sensitivity analysis), cumulative exit rates were above historical control (N01276: 0.652, 95% CI 0.532, 0.772; N01306: 0.704, 95% CI 0.563, 0.844). Overall incidence of TEAEs was 110/150, 73.3% (treatment period); 78/147, 53.1% (baseline AED tapering period); 41/84, 48.8% (BRV monotherapy period). In conclusion, BRV 50 mg/day monotherapy demonstrated an exit rate lower than historical control. Results should be interpreted with caution as, following termination of both studies, patient numbers were too low to evaluate the efficacy of BRV monotherapy. These are the first published safety and tolerability data for BRV monotherapy. Monotherapy was well tolerated, with a relatively low incidence of TEAEs, though this should be interpreted with the caveat that the majority of common TEAEs were likely to have occurred earlier in the course of treatment with BRV. No new safety concerns were identified, supporting the favorable safety profile of BRV observed in adjunctive studies.


Assuntos
Anticonvulsivantes/uso terapêutico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
7.
Epilepsy Behav ; 80: 129-134, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29414542

RESUMO

OBJECTIVE: The objective was to assess the efficacy and safety of adjunctive brivaracetam (BRV) with concomitant use of lamotrigine (LTG) or topiramate (TPM) in patients with uncontrolled focal seizures. METHODS: Data were pooled from three randomized, placebo-controlled Phase III studies (NCT00490035/N01252, NCT00464269/N01253, NCT01261325/N01358) of adults with focal (partial-onset) seizures. Patients taking concomitant levetiracetam were excluded from the efficacy populations, but included in the safety populations. This post-hoc analysis reports data from patients taking BRV in the approved therapeutic range (50-200mg/day) concomitantly with LTG or TPM. RESULTS: The number of patients in each of the three BRV dosage groups was small, particularly for the TPM subgroup. Mean percent reduction over placebo in baseline-adjusted focal seizure frequency/28days for BRV 50, 100, and 200mg/day was 8.7, 5.3, and 8.9 in the LTG subgroup (n=220), and 8.4, 21.3, and -4.2 in the TPM subgroup (n=122). The ≥50% responder rate with concomitant LTG or TPM with BRV 50, 100, and 200mg/day or placebo was LTG: 28.1%, 36.1%, 34.1%, and 29.1%; and TPM: 14.3%, 44.4%, 25.0%, and 17.5%. There were numerically ≥50%, ≥75%, ≥90%, and 100% responder rates for patients taking BRV ≥50mg/day compared with placebo in both subgroups. In the LTG and TPM safety populations (n=245 versus n=125), treatment-emergent adverse events (TEAEs) were reported with LTG 68.7% versus 68.4%, and TPM 65.6% versus 57.8% (BRV ≥50mg/day versus placebo). Discontinuations due to TEAEs versus placebo were LTG 7.3% versus 6.3% and TPM 8.2% versus 4.7%. The three most frequently reported TEAEs for both subgroups were somnolence, dizziness, and fatigue. Of these, the incidence of fatigue in the LTG population appeared to increase with dose. SIGNIFICANCE: In this post-hoc pooled analysis, BRV administered with concomitant LTG or TPM reduced seizure frequency and was generally well tolerated for BRV doses of 50-200mg/day.


Assuntos
Anticonvulsivantes/uso terapêutico , Lamotrigina/uso terapêutico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Topiramato/uso terapêutico , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Tontura/induzido quimicamente , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Fadiga/induzido quimicamente , Feminino , Humanos , Lamotrigina/administração & dosagem , Lamotrigina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pirrolidinonas/administração & dosagem , Pirrolidinonas/efeitos adversos , Sonolência , Topiramato/administração & dosagem , Topiramato/efeitos adversos , Resultado do Tratamento , Adulto Jovem
8.
Clin Pharmacol ; 10: 1-22, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29403319

RESUMO

Brivaracetam (BRV; Briviact) is a new antiepileptic drug (AED) approved for adjunctive treatment of focal (partial-onset) seizures in adults. BRV is a selective, high-affinity ligand for synaptic vesicle 2A (SV2A) with 15- to 30-fold higher affinity than levetiracetam, the first AED acting on SV2A. It has high lipid solubility and rapid brain penetration, with engagement of the target molecule, SV2A, within minutes of administration. BRV has potent broad-spectrum antiepileptic activity in animal models. Phase I studies indicated BRV was well tolerated and showed a favorable pharmacokinetic profile over a wide dose range following single (10-1,000 mg) and multiple (200-800 mg/day) oral dosing. Three pivotal Phase III studies have demonstrated promising efficacy and a good safety and tolerability profile across doses of 50-200 mg/day in the adjunctive treatment of refractory focal seizures. Long-term data indicate that the response to BRV is sustained, with good tolerability and retention rate. BRV is highly effective in patients experiencing secondarily generalized tonic-clonic seizures. Safety data to date suggest a favorable psychiatric adverse effect profile in controlled studies, although limited postmarketing data are available. BRV is easy to use, with no titration and little drug-drug interaction. It can be initiated at target dose with no titration. Efficacy is seen on day 1 of oral use in a significant percentage of patients. Intravenous administration in a 2-minute bolus and 15-minute infusion is well tolerated. Here, we review the pharmacology, pharmacokinetics, and clinical data of BRV.

9.
Nat Commun ; 8(1): 1732, 2017 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-29170366

RESUMO

A strategy for HIV-1 vaccine development is to define envelope (Env) evolution of broadly neutralizing antibodies (bnAbs) in infection and to recreate those events by vaccination. Here, we report host tolerance mechanisms that limit the development of CD4-binding site (CD4bs), HCDR3-binder bnAbs via sequential HIV-1 Env vaccination. Vaccine-induced macaque CD4bs antibodies neutralize 7% of HIV-1 strains, recognize open Env trimers, and accumulate relatively modest somatic mutations. In naive CD4bs, unmutated common ancestor knock-in mice Env+B cell clones develop anergy and partial deletion at the transitional to mature B cell stage, but become Env- upon receptor editing. In comparison with repetitive Env immunizations, sequential Env administration rescue anergic Env+ (non-edited) precursor B cells. Thus, stepwise immunization initiates CD4bs-bnAb responses, but immune tolerance mechanisms restrict their development, suggesting that sequential immunogen-based vaccine regimens will likely need to incorporate strategies to expand bnAb precursor pools.


Assuntos
Anticorpos Neutralizantes/biossíntese , Linfócitos B/imunologia , Anticorpos Anti-HIV/biossíntese , HIV-1/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/imunologia , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , Linfócitos B/citologia , Sítios de Ligação de Anticorpos , Antígenos CD4/metabolismo , Linhagem da Célula/imunologia , Anergia Clonal , Feminino , Técnicas de Introdução de Genes , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/genética , Humanos , Tolerância Imunológica , Imunização/métodos , Macaca mulatta , Masculino , Camundongos , Camundongos Transgênicos , Modelos Moleculares
10.
Epilepsy Res ; 138: 53-61, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29073578

RESUMO

Antiepileptic drug (AED) retention rates are frequently reported in the literature and used to inform clinical decision-making, but methodological differences in the determination of retention rates make comparisons between trials difficult. Open-label extension (OLE) studies of AEDs in patients with focal epilepsy were identified from the literature. Retention calculation methods were reviewed, and published AED retention rates qualitatively compared with corresponding data for brivaracetam (BRV), a synaptic vesicle protein 2A ligand. The search identified 40 publications (corresponding to 17 studies of nine AEDs: eslicarbazepine, gabapentin, lacosamide, levetiracetam, oxcarbazepine, perampanel, pregabalin, topiramate and zonisamide) meeting eligibility criteria for inclusion in the review. Three methodologies to estimate retention rate were identified, which differed in whether patients randomised to placebo in the preceding randomised controlled trials (RCTs) were included or analysed separately, and whether retention was measured from the start of the OLE or of active treatment exposure. The most robust, conservative approach included all patients and measured retention from start of active treatment exposure, whether during the blinded RCT or at the start of the OLE (placebo RCT patients). Data using this method was available for five AEDs in this review, including BRV. The corresponding BRV 52week retention rate (modal doses 50-200mg/day; therapeutic range) was 69.8% (63.3-66.7% for other AEDs at this time point). No statistical indirect comparison was performed, as study populations were clinically heterogeneous. To avoid inconsistencies in methodologies, and allow comparison between AEDs when OLE data are the only long-term data available, retention rate analyses would benefit from the development of consistent reporting standards and guidelines.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Estudos Longitudinais , Pirrolidinonas/uso terapêutico , Tomada de Decisão Clínica , Humanos
11.
J Virol ; 91(21)2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28794027

RESUMO

Dominant antibody responses in vaccinees who received the HIV-1 multiclade (A, B, and C) envelope (Env) DNA/recombinant adenovirus virus type 5 (rAd5) vaccine studied in HIV-1 Vaccine Trials Network (HVTN) efficacy trial 505 (HVTN 505) targeted Env gp41 and cross-reacted with microbial antigens. In this study, we asked if the DNA/rAd5 vaccine induced a similar antibody response in rhesus macaques (RMs), which are commonly used as an animal model for human HIV-1 infections and for testing candidate HIV-1 vaccines. We also asked if gp41 immunodominance could be avoided by immunization of neonatal RMs during the early stages of microbial colonization. We found that the DNA/rAd5 vaccine elicited a higher frequency of gp41-reactive memory B cells than gp120-memory B cells in adult and neonatal RMs. Analysis of the vaccine-induced Env-reactive B cell repertoire revealed that the majority of HIV-1 Env-reactive antibodies in both adult and neonatal RMs were targeted to gp41. Interestingly, a subset of gp41-reactive antibodies isolated from RMs cross-reacted with host antigens, including autologous intestinal microbiota. Thus, gp41-containing DNA/rAd5 vaccine induced dominant gp41-microbiota cross-reactive antibodies derived from blood memory B cells in RMs as observed in the HVTN 505 vaccine efficacy trial. These data demonstrated that RMs can be used to investigate gp41 immunodominance in candidate HIV-1 vaccines. Moreover, colonization of neonatal RMs occurred within the first week of life, and immunization of neonatal RMs during this time also induced a dominant gp41-reactive antibody response.IMPORTANCE Our results are critical to current work in the HIV-1 vaccine field evaluating the phenomenon of gp41 immunodominance induced by HIV-1 Env gp140 in RMs and humans. Our data demonstrate that RMs are an appropriate animal model to study this phenomenon and to determine the immunogenicity in new HIV-1 Env trimer vaccine designs. The demonstration of gp41 immunodominance in memory B cells of both adult and neonatal RMs indicated that early vaccination could not overcome gp41 dominant responses.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Adenoviridae/genética , DNA Viral/genética , Anticorpos Anti-HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Adenoviridae/imunologia , Animais , Animais Recém-Nascidos , Formação de Anticorpos/imunologia , Sequência de Bases , Reações Cruzadas/imunologia , DNA Viral/imunologia , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Humanos , Macaca mulatta , Vacinação
13.
Epilepsy Res ; 131: 70-75, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28279891

RESUMO

Brivaracetam (BRV), a selective, high-affinity ligand for synaptic vesicle protein 2A, is a new antiepileptic drug (AED) for adjunctive treatment of focal (partial-onset) seizures in adults with epilepsy. This post-hoc analysis was conducted to explore the efficacy of adjunctive BRV in patients with prior levetiracetam (LEV) exposure and whether changes in efficacy were related to the similar mechanism of action of these two drugs. Data were pooled from three Phase III studies (NCT00490035; NCT00464269; NCT01261325) of adults with focal seizures taking 1-2 AEDs who received placebo or BRV 50-200mg/day without titration over a 12-week treatment period. Patients taking concomitant LEV at enrollment were excluded from this analysis. Patients were categorized by their status of prior exposure to LEV, carbamazepine (CBZ), topiramate (TPM), or lamotrigine (LTG), to investigate any consistent trend towards reduced response in AED-exposed subgroups compared to AED-naïve subgroups, regardless of the mechanism of action. Study completion rates, percent reduction from baseline in focal seizure frequency over placebo, ≥50% responder rates, and tolerability were evaluated for each subgroup. A total of 1160 patients were investigated. Study completion rates were similar in the AED-exposed subgroups and AED-naïve subgroups. In subgroups with (531 patients) or without (629 patients) prior LEV exposure, ≥50% responder rates for each dose of BRV compared with placebo were generally higher among the LEV-naïve subgroups than the previously LEV-exposed subgroups. LEV-exposed subgroups receiving BRV doses ≥50mg/day showed greater ≥50% responder rates than those receiving placebo. Similar results were observed for CBZ, TPM, and LTG. Previous treatment failure with commonly prescribed AEDs (LEV, CBZ, TPM, or LTG) is associated with a reduced response to BRV irrespective of the mechanism of action. Hence, this post-hoc analysis indicates that previous treatment failure with LEV does not preclude the use of BRV in patients with epilepsy.


Assuntos
Anticonvulsivantes/administração & dosagem , Ensaios Clínicos Fase III como Assunto/métodos , Epilepsia/tratamento farmacológico , Pirrolidinonas/administração & dosagem , Quimioterapia Combinada , Epilepsia/diagnóstico , Epilepsia/epidemiologia , Humanos , Resultado do Tratamento
14.
Epilepsia ; 58(2): e21-e25, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27988967

RESUMO

Time to onset of sustained ≥50% responder status (SRS) was assessed for the pooled patient population receiving brivaracetam (BRV) 50, 100, or 200 mg/day or placebo in three randomized phase III studies (NCT00464269, NCT00490035, and NCT01261325). Patients were aged ≥16 years with well-characterized focal (partial-onset) seizures (FS) uncontrolled by 1-2 concomitant antiepileptic drugs. After an 8-week baseline period, patients received study drug without up-titration for a 12-week (84-day) treatment period. A patient was a sustained ≥50% responder on a particular day if they completed the entire treatment period through day 84 and was a ≥50% responder (based on percent reduction in FS frequency from baseline) both on that day and every successive day until day 84 (end of treatment period). In the pooled efficacy population (N = 1,160), 15.5%, 18.1%, and 19.4% of patients taking BRV 50, 100, or 200 mg/day, respectively, achieved SRS on day 1 versus 6.7% for placebo (p < 0.001). Statistically significant SRS was also achieved for most of the BRV-treated groups in the three separate studies. This suggests that BRV has an early, sustained onset of action in a subset of responders. The incidence of adverse events during the first week was similar to that in the overall treatment period.


Assuntos
Anticonvulsivantes/uso terapêutico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Fatores de Tempo , Resultado do Tratamento
15.
JCI Insight ; 1(20): e88522, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27942585

RESUMO

The ALVAC prime/ALVAC + AIDSVAX B/E boost RV144 vaccine trial induced an estimated 31% efficacy in a low-risk cohort where HIV­1 exposures were likely at mucosal surfaces. An immune correlates study demonstrated that antibodies targeting the V2 region and in a secondary analysis antibody-dependent cellular cytotoxicity (ADCC), in the presence of low envelope-specific (Env-specific) IgA, correlated with decreased risk of infection. Thus, understanding the B cell repertoires induced by this vaccine in systemic and mucosal compartments are key to understanding the potential protective mechanisms of this vaccine regimen. We immunized rhesus macaques with the ALVAC/AIDSVAX B/E gp120 vaccine regimen given in RV144, and then gave a boost 6 months later, after which the animals were necropsied. We isolated systemic and intestinal vaccine Env-specific memory B cells. Whereas Env-specific B cell clonal lineages were shared between spleen, draining inguinal, anterior pelvic, posterior pelvic, and periaortic lymph nodes, members of Env­specific B cell clonal lineages were absent in the terminal ileum. Env­specific antibodies were detectable in rectal fluids, suggesting that IgG antibodies present at mucosal sites were likely systemically produced and transported to intestinal mucosal sites.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos B/classificação , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/prevenção & controle , Imunidade nas Mucosas , Animais , Anticorpos Anti-HIV/análise , Proteína gp120 do Envelope de HIV/administração & dosagem , Imunização Secundária , Imunoglobulina G/análise , Macaca mulatta
16.
Epilepsy Res ; 127: 179-185, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27608437

RESUMO

PURPOSE: Secondarily generalized tonic-clonic seizures (SGTCS) are among the most devastating types of seizures, contributing to increased morbidity and mortality. Brivaracetam (BRV), a selective, high-affinity ligand for synaptic vesicle 2A (SV2A), has been shown to be useful for the adjunctive treatment of focal seizures. We sought to determine its specific efficacy in treating SGTCS. METHODS: Data were pooled from three Phase III studies (NCT00490035; NCT00464269; NCT01261325) of adults with focal seizures taking 1-2 antiepileptic drugs (AEDs) who received placebo or BRV 50-200mg/day without titration over a 12-week treatment period. We report efficacy and safety/tolerability data for the BRV therapeutic dose range (50-200 mg/day) in patients with focal seizures including baseline SGTCS. RESULTS: Patients (efficacy population, N=409) had been diagnosed with epilepsy for a mean±standard deviation duration of 22.2±13.1years. Baseline median SGTCS frequency was 3.0 per 28days. The majority (293, 71.6%) had failed ≥2 AEDs prior to study enrollment. The median percent reduction from baseline in SGTCS frequency/28days was: placebo, 33.3%; BRV 50mg/day, 66.6% (p<0.001); BRV 100mg/day, 61.2% (p=0.002); and BRV 200mg/day, 82.1% (p<0.001). The ≥50% responder rate for SGTCS was: placebo, 33.0%; BRV 50mg/day, 61.3% (p=0.003); BRV 100mg/day, 55.0% (p<0.001); and BRV 200mg/day, 64.0% (p<0.001). Freedom from SGTCS was achieved by: placebo, 14.8%; BRV 50mg/day, 22.6%; BRV 100mg/day, 31.0%; and BRV 200mg/day, 36.0% of patients. Time to first SGTCS during the treatment period was longer in patients receiving BRV than placebo (26days vs 8days, hazard ratio 0.55, p<0.001). In the SGTCS safety population (N=487), treatment-emergent adverse events (TEAEs) were reported by 60.6% of patients receiving placebo vs 65.0% of patients receiving BRV ≥50mg/day. Serious TEAEs were reported by 3.1% placebo vs 3.9% BRV ≥50mg/day. Discontinuations due to TEAEs were 3.9% placebo vs 6.3% BRV ≥50mg/day. CONCLUSIONS: In patients with drug-resistant focal seizures, adjunctive BRV is effective in reducing the frequency of SGTCS. Almost one-third (30.4%) of patients were rendered completely free of SGTCS during the 12-week treatment period when taking BRV ≥50mg/day. BRV was well tolerated, with a TEAE profile consistent with that of the overall study population.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia Tônico-Clônica/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/efeitos adversos , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Pirrolidinonas/efeitos adversos , Resultado do Tratamento , Adulto Jovem
17.
Epilepsy Res ; 127: 114-118, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27589414

RESUMO

INTRODUCTION: This analysis was conducted to assess the tolerability, safety, and efficacy of brivaracetam (BRV) for adjunctive treatment of focal (partial-onset) seizures in patients aged ≥65 years. METHODS: Safety/tolerability and efficacy data for patients aged ≥65 years were pooled from three randomized, double-blind, placebo-controlled, fixed-dose Phase III studies (NCT00490035, NCT00464269, and NCT01261325). Data were pooled by treatment group: placebo or the proposed therapeutic dose range of 50-200 mg/day: BRV 50, 100, 200mg/day. RESULTS: Thirty-two patients aged ≥65 years were randomized to placebo or BRV 50-200 mg/day. Of these, 30 patients (93.8%) completed their respective study. In the safety population (n=32), 87.5% placebo- vs 73.3% BRV-treated patients reported treatment-emergent adverse events (TEAEs) during the treatment period; most commonly, headache (25.0% vs 12.5%), paresthesia (0% vs 12.5%), and somnolence (50.0% vs 12.5%) for placebo- vs BRV-treated patients, respectively. During the treatment period, drug-related TEAEs were reported by 62.5% of placebo- vs 53.3% of BRV-treated patients, and serious TEAEs (SAEs) were reported by 0% of placebo- and 4.2% of BRV-treated patients; there were no drug-related SAEs and no deaths. Three SAEs (placebo 1/8; BRV 2/24) and two deaths (placebo 1/8; BRV 1/24) occurred in the post-treatment period. In the efficacy population (n=31), median percent reduction from baseline in focal seizure frequency/28days was 14.0% for placebo vs 25.5%, 49.6%, and 74.9% for BRV 50, 100, and 200 mg/day, respectively. The ≥50% responder rate was 14.3% for placebo vs 25.0%, 50.0%, and 66.7% for BRV 50, 100, and 200 mg/day, respectively. CONCLUSIONS: Safety/tolerability and efficacy findings in this small subgroup of older patients treated with adjunctive BRV are consistent with those observed in the much larger overall pooled population. BRV may be a suitable adjunctive treatment for older patients with uncontrolled focal seizures. Further larger studies in this population are warranted.


Assuntos
Anticonvulsivantes/uso terapêutico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Idoso , Anticonvulsivantes/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pirrolidinonas/efeitos adversos , Terapêutica
18.
Epilepsia ; 57(7): 1139-51, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27265725

RESUMO

OBJECTIVES: To report pooled safety/tolerability and seizure outcome data from adults with uncontrolled partial-onset (focal) seizures (POS) receiving adjunctive brivaracetam (BRV) during phase IIb/III and long-term follow-up (LTFU) studies. METHODS: Seizure outcome data were pooled from phase IIb (NCT00175929 and NCT00175825), III/IIIb (NCT00490035, NCT00464269, NCT00504881, and NCT01261325) and associated LTFU studies (NCT00175916, NCT00150800, and NCT01339559). Safety/tolerability data were pooled from these studies plus NCT01405508, NCT01653262, and NCT01728077 (LTFU). Patients received placebo (during core studies) or BRV 5-200 mg/day. Safety/tolerability and seizure outcomes (BRV modal doses 50-200 mg/day) were assessed until January 17, 2014. RESULTS: Of 2,186 patients (97.3% with POS and 2.7% with other seizure types) who received BRV 50-200 mg/day, 2,051 (93.8%) completed core studies and continued in LTFU studies. Total BRV exposure: 5,339.4 patient-years (≥8.0 years in 41 patients); 6-, 12-, 24-, and 60-month retention: 91.0%, 79.8%, 68.1%, and 54.4%, respectively. Safety/tolerability data pooled from 2,186 patients: ≥1 treatment-emergent adverse event (TEAE) reported by 1,848 (84.5%) patients; 1,184 (54.2%) reported ≥1 TEAE considered treatment-related. Most frequent TEAEs (≥10%): headache (20.9%), dizziness (17.5%), somnolence (15.2%), nasopharyngitis (13.2%), fatigue (11.3%), and convulsion (10.6%). Serious TEAEs (SAEs) and treatment-related SAEs: 401 (18.3%) and 95 (4.3%) patients, respectively. Of 28 (1.3%) deaths, four (14.3%) were considered possibly treatment related by the investigator. Pooled seizure outcome data (1,836 patients): median POS frequency/28 days at baseline was 8.9; on treatment, median percentage reduction from baseline in POS/28 days was 48.8%, and ≥50% responder rate was 48.7%. Complete seizure freedom: 4.9%, 4.2%, 3.0%, and 3.3% for ≥6, 12, 24, and 60 months, respectively. Improvements were seen in health-related quality of life (HRQoL) from baseline, assessed by Quality of Life in Epilepsy Inventory-31. SIGNIFICANCE: Adjunctive BRV treatment in adults with POS was effective and generally well tolerated when administered long-term (≥8.0 years). Retention was high and HRQoL improvements were observed.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Resultado do Tratamento , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Neurology ; 87(3): 314-23, 2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27335114

RESUMO

OBJECTIVE: To assess the efficacy, safety, and tolerability of adjunctive brivaracetam (BRV), a selective, high-affinity ligand for SV2A, for treatment of partial-onset (focal) seizures (POS) in adults. METHODS: Data were pooled from patients (aged 16-80 years) with POS uncontrolled by 1 to 2 antiepileptic drugs receiving BRV 50, 100, or 200 mg/d or placebo, without titration, in 3 phase III studies of BRV (NCT00490035, NCT00464269, and NCT01261325, ClinicalTrials.gov, funded by UCB Pharma). The studies had an 8-week baseline and a 12-week treatment period. Patients receiving concomitant levetiracetam were excluded from the efficacy pool. RESULTS: In the efficacy population (n = 1,160), reduction over placebo (95% confidence interval) in baseline-adjusted POS frequency/28 days was 19.5% (8.0%-29.6%) for 50 mg/d (p = 0.0015), 24.4% (16.8%-31.2%) for 100 mg/d (p < 0.00001), and 24.0% (15.3%-31.8%) for 200 mg/d (p < 0.00001). The ≥50% responder rate was 34.2% (50 mg/d, p = 0.0015), 39.5% (100 mg/d, p < 0.00001), and 37.8% (200 mg/d, p = 0.00003) vs 20.3% for placebo (p < 0.01). Across the safety population groups (n = 1,262), 90.0% to 93.9% completed the studies. Treatment-emergent adverse events (TEAEs) were reported by 68.0% BRV overall (n = 803) and 62.1% placebo (n = 459). Serious TEAEs were reported by 3.0% (BRV) and 2.8% (placebo); 3 patients receiving BRV and one patient receiving placebo died. TEAEs in ≥5% patients taking BRV (vs placebo) were somnolence (15.2% vs 8.5%), dizziness (11.2% vs 7.2%), headache (9.6% vs 10.2%), and fatigue (8.7% vs 3.7%). CONCLUSIONS: Adjunctive BRV was effective and generally well tolerated in adults with POS. CLASSIFICATION OF EVIDENCE: This analysis provides Class I evidence that adjunctive BRV is effective in reducing POS frequency in adults with epilepsy and uncontrolled seizures.


Assuntos
Epilepsias Parciais/tratamento farmacológico , Pirrolidinonas/efeitos adversos , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Levetiracetam , Masculino , Pessoa de Meia-Idade , Piracetam/administração & dosagem , Piracetam/análogos & derivados , Piracetam/uso terapêutico , Pirrolidinonas/administração & dosagem , Adulto Jovem
20.
Neurology ; 86(19): 1785-93, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27164714

RESUMO

OBJECTIVE: This double-blind, placebo-controlled, interventional trial was conducted to investigate the effects of rotigotine patch on periodic limb movement (PLM)-associated nocturnal systolic blood pressure (SBP) elevations. METHODS: Patients with moderate to severe restless legs syndrome (RLS) were randomized to rotigotine (optimal dose [1-3 mg/24 h]) or placebo. Continuous beat-to-beat blood pressure (BP) assessments were performed during polysomnography at baseline and at the end of 4-week maintenance. Primary outcome was change in number of PLM-associated SBP elevations (defined as slope of linear regression ≥2.5 mm Hg/beat-to-beat interval over 5 consecutive heartbeats [≥10 mm Hg]). Additional outcomes were total SBP elevations, PLM-associated and total diastolic BP (DBP) elevations, periodic limb movements index (PLMI), and PLM in sleep arousal index (PLMSAI). RESULTS: Of 81 randomized patients, 66 (37 rotigotine, 29 placebo) were included in efficacy assessments. PLM-associated SBP elevations were significantly reduced with rotigotine vs placebo (least squares mean treatment difference [95% confidence interval (CI)] -160.34 [-213.23 to -107.45]; p < 0.0001). Rotigotine-treated patients also had greater reduction vs placebo in total SBP elevations (-161.13 [-264.47 to -57.79]; p = 0.0028), PLM-associated elevations (-88.45 [-126.12 to -50.78]; p < 0.0001), and total DBP elevations (-93.81 [-168.45 to -19.16]; p = 0.0146), PLMI (-32.77 [-44.73 to -20.80]; p < 0.0001), and PLMSAI (-7.10 [-11.93 to -2.26]; p = 0.0047). Adverse events included nausea (rotigotine 23%; placebo 8%), headache (18% each), nasopharyngitis (18%; 8%), and fatigue (13%; 15%). CONCLUSIONS: Further investigation is required to determine whether reductions in nocturnal BP elevations observed with rotigotine might modify cardiovascular risk. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for patients with moderate to severe RLS, rotigotine at optimal dose (1-3 mg/24 h) reduced PLM-associated nocturnal SBP elevations.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Agonistas de Dopamina/administração & dosagem , Síndrome da Mioclonia Noturna/tratamento farmacológico , Síndrome das Pernas Inquietas/fisiopatologia , Tetra-Hidronaftalenos/administração & dosagem , Tiofenos/administração & dosagem , Adolescente , Adulto , Idoso , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Agonistas de Dopamina/efeitos adversos , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Humanos , Análise dos Mínimos Quadrados , Pessoa de Meia-Idade , Síndrome da Mioclonia Noturna/complicações , Síndrome da Mioclonia Noturna/fisiopatologia , Fotoperíodo , Polissonografia , Síndrome das Pernas Inquietas/complicações , Síndrome das Pernas Inquietas/tratamento farmacológico , Índice de Gravidade de Doença , Tetra-Hidronaftalenos/efeitos adversos , Tiofenos/efeitos adversos , Adesivo Transdérmico/efeitos adversos , Resultado do Tratamento , Adulto Jovem
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