Nonspecific oral medications versus anti-calcitonin gene-related peptide monoclonal antibodies for migraine: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: To compare calcitonin gene-related peptide monoclonal antibodies (CGRP mAbs) versus nonspecific oral migraine preventives (NOEPs). BACKGROUND: Insurers mandate step therapy with NOEPs before approving CGRP mAbs. METHODS: Databases were searched for class I or II randomized controlled trials (RCTs) comparing CGRP mAbs or NOEPs versus placebo for migraine prevention in adults. The primary outcome measure was monthly migraine days (MMD) or moderate to severe headache days. RESULTS: Twelve RCTs for CGRP mAbs, 5 RCTs for topiramate, and 3 RCTs for divalproex were included in the meta-analysis. There was high certainty that CGRP mAbs are more effective than placebo, with weighted mean difference (WMD; 95% confidence interval) of -1.64 (-1.99 to -1.28) MMD, which is compatible with small effect size (Cohen's d -0.25 [-0.34 to -0.16]). Certainty of evidence that topiramate or divalproex is more effective than placebo was very low and low, respectively (WMD -1.45 [-1.52 to -1.38] and -1.65 [-2.30 to -1.00], respectively; Cohen's d -1.25 [-2.47 to -0.03] and -0.48 [-0.67 to -0.29], respectively). Trial sequential analysis showed that information size was adequate and that CGRP mAbs had clear benefit versus placebo. Network meta-analysis showed no statistically significant difference between CGRP mAbs and topiramate (WMD -0.19 [-0.56 to 0.17]) or divalproex (0.01 [-0.73 to 0.75]). No significant difference was seen between topiramate or divalproex (0.21 [-0.45 to 0.86]). CONCLUSIONS: There is high certainty that CGRP mAbs are more effective than placebo, but the effect size is small. When feasible, CGRP mAbs may be prescribed as first-line preventives; topiramate or divalproex could be as effective but are less well tolerated. The findings of this study support the recently published 2024 position of the American Headache Society on the use of CGRP mAbs as the first-line treatment.

Vascular dysfunction programmed in male rats by topiramate during peripubertal period.

AIM: The present study evaluated whether topiramate (TPM) treatment during the peripubertal period affects vascular parameters of male rats and whether oxidative stress plays a role in these changes. MAIN METHODS: Rats were treated with TPM (41 mg/kg/day, gavage) or vehicle (CTR group) from the postnatal day (PND) 28 to 50. At PND 51 and 120 the rats were evaluated for: thoracic aorta reactivity to phenylephrine, in the presence (Endo+) or absence of endothelium (Endo-), to acetylcholine and to sodium nitroprusside (SNP), aortic thickness and endothelial nitric oxide synthase (eNOS) expression. In serum were analyzed: the antioxidant capacity by ferric reducing antioxidant power assay; endogenous antioxidant reduced glutathione, and superoxide anion. Results were expressed as mean ± s.e.m., differences when p < 0.05. STATISTICS: Two-way ANOVA (and Tukey's) or Student t-test. KEY FINDINGS: At PND 51, the contraction induced by phenylephrine in Endo+ ring was higher in TPM when compared to CTR. At PND 120, the aortic sensitivity to acetylcholine in TPM rats was reduced in comparison with CTR. The aortic eNOs expression and the aortic thickness were similar between the groups. At PND 51 and 120, TPM group presented a decrease in antioxidants when compared to CTR groups and at PND 120, in TPM group the superoxide anion was increased. SIGNIFICANCE: Taken together, the treatment of rats with TPM during peripubertal period promoted permanent impairment of endothelial function probably mediated by oxidative stress.

Comparison of neuroprotective effects of a topiramate-loaded biocomposite based on mesoporous silica nanoparticles with pure topiramate against methylphenidate-induced neurodegeneration.

BACKGROUND: Methylphenidate (MPH) abuse has been criticized for its role in neurodegeneration. Also, a high risk of seizure was reported in the first month of MPH treatment. Topiramate, a broad-spectrum Antiepileptic Drug (AED), has been used as a neuroprotective agent in both aforementioned complications. Nanotechnology is introduced to increase desirable neurological treatment with minimum side effects. We aimed to investigate the potential neuroprotective activity of topiramate loaded on nanoparticles. METHODS AND RESULTS: MTT assay was performed to evaluate the cellular cytotoxicity of Mesoporous Silica Nanoparticles (MSN). Male rats were randomly divided into eight groups. Rats received an intraperitoneal (i.p) MPH (10 mg/kg) injection and a daily oral dose of topiramate (TPM, 30 mg/kg), MSN with Zn core (10 and 30 mg/kg), and MSN with Cu core (10 and 30 mg/kg) for three weeks. On day 21, a seizure was induced by a single injection of pentylenetetrazole (PTZ) to evaluate the protective effects of TPM-loaded nanoparticles on seizure latency and duration following MPH-induced neurotoxicity. Moreover, the hippocampal content of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), malondialdehyde (MDA), and the anti-oxidant enzymes (SOD, GPx, and GR) activities were assessed. Also, BAX and Bcl-2 as two main apoptotic markers were evaluated. RESULTS: MPH neurotoxicity was observed as a raised duration and reduced latency in PTZ-induced seizure. However, TPM-loaded MSN with Zn species (NE) treatment reduced the duration and improved the latency time. Also, NE and, somewhat, TPM-loaded MSN with Cu species (NM) administration reduced inflammatory cytokines, MDA, and Bax levels and increased activities in the rat hippocampus. CONCLUSION: TPM-loaded nanoparticles could be used as neuroprotective agents against MPH-induced neurodegeneration by improving seizure parameters and reducing inflammatory, oxidant, and apoptotic factors.

Imperatorin interacts additively with novel antiseizure medications in the mouse maximal electroshock-induced seizure model: an isobolographic transformation.

BACKGROUND: Anticonvulsant effects of imperatorin (IMP) have been experimentally confirmed earlier, but no information is available on the interaction profiles of this naturally occurring coumarin when combined with novel antiseizure medication (ASMs). This study aimed to determine the effects of IMP on the anticonvulsant effects of lacosamide (LCM), oxcarbazepine (OXC), pregabalin (PGB), and topiramate (TPM) in the maximal electroshock-induced seizure (MES) model in mice. METHODS: The anticonvulsant effects exerted by novel ASMs (LCM, OXC, PGB, and TPM) when combined with constant doses of IMP (25 and 50 mg/kg) underwent isobolographic transformation to precisely classify the observed interactions in the mouse MES model. Total brain concentrations of ASMs were measured with high-pressure liquid chromatography to exclude the pharmacokinetic nature of interactions among IMP and the tested ASMs. RESULTS: IMP (50 mg/kg) significantly enhanced (p < 0.01) the anticonvulsant potency of LCM, OXC, PGB, and TPM in the mouse MES model. IMP (25 mg/kg) mildly potentiated the anticonvulsant action of LCM, OXC, PGB, and TPM, but no statistical significance was reported for these combinations. The isobolographic transformation of data from the MES test revealed that the interactions of novel ASMs with IMP were additive. Moreover, IMP (50 mg/kg) did not affect the total brain content of any of the novel ASMs in experimental mice. CONCLUSIONS: The additive interactions of IMP with LCM, OXC, PGB, and TPM in the mouse MES model accompanied by no pharmacokinetic changes in the total brain content of ASMs are worthy of recommendation for further studies.

Protective effects of topiramate on acetic acid-induced colitis in rats through the inhibition of oxidative stress.

Ulcerative colitis is an intestinal inflammatory condition characterized by a rise in inflammatory mediator production and oxidative stress. Topiramate is an anticonvulsant agent with effectiveness on a wide range of seizures, which is anti-oxidative. This study aims to examine the protective effects of topiramate on acetic acid-induced ulcerative colitis in rats. Rats were randomly divided into four groups as follows: control, acetic acid, acetic acid + topiramate, and acetic acid + dexamethasone groups. Topiramate (100 mg/kg/day) or dexamethasone (2 mg/kg/day) was administered for six consecutive days, and ulcerative colitis was induced on the first day of the study by transrectal administration of 4% acetic acid. Four hours after the last dose of treatments, animals of each group were sacrificed, and colon tissues were removed for further macroscopic, histopathologic, and biochemical analyses. Treatment with topiramate markedly decreased colonic lesions and macroscopic scores as well as the improvement of histopathologic changes. Topiramate also effectively decreased the levels of malondialdehyde and upregulated the activity of anti-oxidative enzymes, including catalase, superoxide dismutase, and glutathione peroxidase. Our results reveal that the administration of topiramate ameliorates acetic acid-induced colitis in rats via anti-oxidative properties, and further studies may introduce it as an effective therapeutic candidate to decrease ulcerative colitis severity.

Impact of maternal topiramate ingestion on ossification of skull and appendicular bones in rat fetuses.

The skull and appendicular bones are derived from different embryological sources during their development. The impact of prenatal exposure of topiramate on ossification of these bones is not adequately studied. The goal of this study was to assess the ossification patterns of the craniofacial bones and bones of the forelimbs and hindlimbs in 20-day-old rat fetuses after maternal exposure to topiramate at doses equivalent to human therapeutic doses. Three groups of Sprague-Dawley pregnant rats were used: control, topiramate 50mg/kg/day (T50) and topiramate 100mg/kg/day (T100). Topiramate was given by oral gavage from day 6 to day19 of gestation. Ossification was evaluated in the bones of 20 days fetuses after staining with Alizarin red. Results showed a significant reduction in complete ossified centers of the metacarpal, metatarsal and craniofacial bones in topiramate-exposed fetuses at both doses when compared to the control group. Also, a significant decrease in the length of ossified part of the long bones of the forelimbs and hindlimbs in topiramate-exposed fetuses at both doses was noted when compared to the control group. Crown-rump length and fetal weight were significantly decreased in topiramate treated groups compared to the control group. In all examined groups, there was a positive correlation between the crown-rump length and the lengths of humerus and femur. No abnormalities in the ossified bones and no significant changes in their ossification pattern were observed between the treated groups. In conclusion, prenatal administration of topiramate in doses equivalent to human therapeutic doses delayed ossification and development of craniofacial and appendicular bones in rat fetuses and their effects are not dose dependent at doses investigated. The implications of these findings in women who require topiramate therapy in pregnancy merit further evaluation.

Ameliorative Effect of Cannabidiol on Topiramate-Induced Memory Loss: The Role of Hippocampal and Prefrontal Cortical NMDA Receptors and CREB/BDNF Signaling Pathways in Rats.

Cannabidiol (CBD) is a promising neurological agent with potential beneficial effects on memory and cognitive function. The combination of CBD and topiramate in the treatment of some neurological diseases has been of great interest. Since Topiramate-induced memory loss is a major drawback of its clinical application and the overall effect of the combination of CBD and topiramate on memory is still unclear, here we investigated the effect of CBD on topiramate-induced memory loss and the underlying molecular mechanisms. A one trial step-through inhibitory test was used to evaluate memory consolidation in rats. Moreover, the role of N-methyl-D-aspartate receptors (NMDARs) in the combination of CBD and topiramate in memory consolidation was evaluated through the intra-CA1 administration of MK-801 and NMDA. Western blot analysis was used to evaluate variations in brain-derived neurotrophic factor (BDNF) and phosphorylated cyclic AMP response element-binding protein (pCREB)/CREB ratio in the prefrontal cortex (PFC) and hippocampus (HPC). While the intraperitoneal (i.p.) administration of topiramate (50, 75, and 100 mg/kg) significantly reduced inhibitory time latency, the i.p. administration of CBD (20 and 40 mg/kg) could effectively reverse these effects. Similarly, the sub-effective doses of NMDA plus CBD (10 mg/kg) could improve the topiramate-induced memory loss along with an enhancement in BDNF and pCREB expression in the PFC and HPC. Contrarily, the administration of sub-effective doses of the NMDAR antagonist (MK-801) diminished the protective effects of CBD (20 mg/kg) on topiramate-induced memory loss associated with decreased BDNF and pCREB levels in the PFC and HPC. These findings suggest that CBD can improve topiramate-induced memory impairment, partially by the NMDARs of the PFC and HPC, possibly regulated by the CREB/BDNF signaling pathway.

Acetazolamide and topiramate lower intracranial pressure through differential mechanisms: The effect of acute and chronic administration.

BACKGROUND AND PURPOSE: Diseases of raised intracranial pressure (ICP) cause severe morbidity and mortality. Multiple drugs are utilised to lower ICP including acetazolamide and topiramate. However, the evidence for their use is unclear. We aimed to assess the ICP modulatory effects and molecular effects at the choroid plexus (CP) of acetazolamide and topiramate. EXPERIMENTAL APPROACH: Female rats were implanted with telemetric ICP probes for physiological, freely moving 24/7 ICP recordings. Randomised cross-over studies were performed, where rats received acute (24 h) high doses of acetazolamide and topiramate, and chronic (10 days) clinically equivalent doses of acetazolamide and topiramate, all via oral gavage. Cerebrospinal fluid (CSF) secretion assays, and RT-qPCR and western blots on in vitro and in vivo CP, were used to investigate drug actions. KEY RESULTS: We demonstrate that acetazolamide and topiramate achieved maximal ICP reduction within 120 min of administration, and in combination doubled the ICP reduction over a 24-h period. Chronic administration of acetazolamide or topiramate lowered ICP by 25%. Topiramate decreased CSF secretion by 40%. Chronic topiramate increased the gene expression of Slc12a2 and Slc4a10 and protein expression of the sodium-dependent chloride/bicarbonate exchanger (NCBE), whereas chronic acetazolamide did not affect the expression of assessed genes. CONCLUSIONS AND IMPLICATIONS: Acetazolamide and topiramate are effective at lowering ICP at therapeutic levels. We provide the first evidence that topiramate lowers CSF secretion and that acetazolamide and topiramate may lower ICP via distinct molecular mechanisms. Thus, the combination of acetazolamide and topiramate may have utility for treating raised ICP.

Current treatment options for cluster headache: limitations and the unmet need for better and specific treatments-a consensus article.

AIM: Treatment for cluster headache is currently based on a trial-and-error approach. The available preventive treatment is unspecific and based on few and small studies not adhering to modern standards. Therefore, the authors collaborated to discuss acute and preventive treatment in cluster headache, addressing the unmet need of safe and tolerable preventive medication from the perspectives of people with cluster headache and society, headache specialist and cardiologist. FINDINGS: The impact of cluster headache on personal life is substantial. Mean annual direct and indirect costs of cluster headache are more than 11,000 Euros per patient. For acute treatment, the main problems are treatment response, availability, costs and, for triptans, contraindications and the maximum use allowed. Intermediate treatment with steroids and greater occipital nerve blocks are effective but cannot be used continuously. Preventive treatment is sparsely studied and overall limited by relatively low efficacy and side effects. Neurostimulation is a relevant option for treatment-refractory chronic patients. From a cardiologist's perspective use of verapamil and triptans may be worrisome and regular follow-up is essential when using verapamil and lithium. CONCLUSION: We find that there is a great and unmet need to pursue novel and targeted preventive modalities to suppress the horrific pain attacks for people with cluster headache.

Optimization of the Zebrafish Larvae Pentylenetetrazol-Induced Seizure Model for the Study of Caffeine and Topiramate Interactions.

Epilepsy is a common neurological disorder characterized by seizures that cause neurobiological and behavioral impairment. Caffeine (CAF), which is the most widely consumed stimulant in the world, is reported to influence epileptic seizures and antiepileptic drugs, especially topiramate (TPM). The aim of the study was to optimize the zebrafish larvae pentylenetetrazol-induced seizure model for the study of CAF and TPM interactions, which include the determination of dose space, and the delivery of an analytical method for monitoring CAF, TPM, and CAF metabolite paraxanthine (PAR) in Zebrafish larvae. Methods: The zebrafish larvae, 4 days post-fertilization, were incubated for 18 h with CAF, TPM, or CAF + TPM, with subsequent locomotor activity assessment. Seizures were evoked by adding PTZ solution to obtain a final concentration of 20 mM. Subsequently, the liquid chromatography-mass spectrometry (LC-MS/MS) analytical method was used to simultaneously assess the levels of both CAF and TPM in the larvae. CAF (50 mg/L) and TPM (75 µM) given separately decreased the average larvae locomotor activity compared to the PTZ group but, however, were not able to lower it to the control level. Co-administration of 25 mg/L CAF and 50 µM TPM suppressed the activity to the same level. Adding 25 µM TPM to 50 mg/L CAF decrease the measured CAF level in the larvae. Until proven otherwise, CAF consumption should be regarded as a potential determinant in the modulation of TPM's efficacy in the management of epileptic seizures. The optimized model will contribute to the standardization of studying CAF and TPM interactions and building the understanding of the molecular bases of the interaction.

The protective effects of topiramate and spirulina against doxorubicin-induced cardiotoxicity in rats.

Doxorubicin (DOX) is a widely used chemotherapy drug that can cause significant cardiotoxicity, limiting its clinical application. This study aimed to investigate the potential protective effects of topiramate (TPM) and spirulina (SP), either alone or in combination, in preventing DOX-induced cardiotoxicity. Adult Sprague Dawley rats were divided into five groups, including a normal control group and groups receiving DOX alone, DOX with TPM, DOX with SP, or DOX with a combination of TPM and SP. Cardiotoxicity was induced by administering DOX intraperitoneally at a cumulative dose of 16 mg/kg over 4 weeks. TPM and/or SP administration started 1 week before DOX treatment and continued for 35 days. Body weight, serum markers of cardiac damage, oxidative stress and inflammatory parameters were assessed. Histopathological and immunohistochemical examinations were performed on cardiac tissues. Results showed that TPM and SP monotherapy led to significant improvements in serum levels of cardiac markers, decreased oxidative stress, reduced fibrosis-related growth factor levels, increased antioxidant levels, and improved histopathological features. SP demonstrated more prominent effects in comparison to TPM, and the combination of TPM and SP exhibited even more pronounced effects. In conclusion, TPM and SP, either alone or in combination, hold promise as therapeutic interventions for mitigating DOX-induced cardiotoxicity.

Cognitive effect of antiseizure medications in medial temporal lobe epilepsy.

BACKGROUND AND PURPOSE: The specific effects of antiseizure medications (ASMs) on cognition are a rich field of study, with many ongoing questions. The aim of this study was to evaluate these effects in a homogeneous group of patients with epilepsy to guide clinicians to choose the most appropriate medications. METHODS: We retrospectively identified 287 refractory patients with medial temporal lobe epilepsy associated with hippocampal sclerosis. Scores measuring general cognition (global, verbal and performance IQ), working memory, episodic memory, executive functions, and language abilities were correlated with ASM type, number, dosage and generation (old vs. new). We also assessed non-modifiable factors affecting cognition, such as demographics and epilepsy-related factors. RESULTS: Key parameters were total number of ASMs and specific medications, especially topiramate (TPM) and sodium valproate (VPA). Four cognitive profiles of the ASMs were identified: (i) drugs with an overall detrimental effect on cognition (TPM, VPA); (ii) drugs with negative effects on specific areas: verbal memory and language skills (carbamazepine), and language functions (zonisamide); (iii) drugs affecting a single function in a specific and limited area: visual denomination (oxcarbazepine, lacosamide); and (iv) drugs without documented cognitive side effects. Non-modifiable factors such as age at testing, age at seizure onset, and history of febrile seizures also influenced cognition and were notably influenced by total number of ASMs. CONCLUSION: We conclude that ASMs significantly impact cognition. Key parameters were total number of ASMs and specific medications, especially TPM and VPA. These results should lead to a reduction in the number of drugs received and the avoidance of medications with unfavorable cognitive profiles.

Topiramate treatment during the peripubertal period does not alter aortic endothelial function in female Wistar rats.

AIMS: This study aimed to evaluate the short- and long-term adverse effects of blood pressure (BP), vascular endothelial function, and estrogen receptor (ERα and ERß) modulation on endothelial function in female Wistar rats treated with topiramate (TPM), an antiepileptic drug, during the peripubertal period. MATERIALS AND METHODS: Female Wistar rats were treated with TPM (41 mg/kg) or water (CTR group) by gavage from postnatal day (PND) 28 to 50 (peripubertal phase). At the end of the treatment, the TPM and CTR rats were divided into two groups and evaluated after 24 h or from PND 85 (adulthood). The rats were evaluated for: thoracic aorta reactivity to phenylephrine (Phenyl), acetylcholine (ACh), and sodium nitroprusside (SNP); aortic ring reactivity after ERα and ERß antagonism; and BP. KEY FINDINGS: It was observed that vascular response to Phenyl, ACh, and SNP was similar between TPM and CTR rats in the short- and long-term evaluations. In addition, the ER antagonism did not interfere with aortic contraction or relaxation in either TPM or CTR. SIGNIFICANCE: Taken together, the results show that TPM treatment during the peripubertal period does not alter aortic endothelial function and its estrogen modulation via classic ER in female Wistar rats, suggesting that TPM treatment in this period is safe for the vascular system.

Effects of topiramate on morphological and structural alterations of the anterior cingulate cortex in aggressive socially isolated mice.

RATIONALE: Topiramate, an approved antiepileptic drug, was found effective in treating aggressive symptoms in humans and rodents. However, the effects and mechanisms of Topiramate on aggressive behavior are still unclear. Our previous study indicated that intraperitoneal administration of Topiramate successfully decreased aggression and reinforced sociability in socially aggressive mice, and increased cFos-expressing neurons in the anterior cingulate cortex (ACC). In addition to its pharmacological properties, previous studies have approved the neuroprotective effects of Topiramate. These suggest a potential effect of Topiramate on ACC's structure and function. OBJECTIVES AND RESULTS: In the present study, we first investigated the structural characteristics of ACC in the social isolation-induced aggression paradigm. The results showed that hyper-aggressive behavior in socially aggressive mice was associated with several structural alterations in ACC: increased neuron death combined with decreased neuron density, increased damaged neuronal morphology and increased neuroinflammation markers. Based on these observations, we next investigated the potential neuroprotective effect of Topiramate against structural alterations of ACC observed in socially aggressive mice. Results indicated that intraperitoneal administration of Topiramate (30 mg/kg) decreased aggression and enhanced sociability without affecting locomotor activity. Interestingly, the anti-aggressive effect of Topiramate was associated with decreased neuronal death, ameliorated damaged neuronal morphology, and decreased reactive microglia markers in ACC. CONCLUSIONS: Our results provide insights into the structural alterations of ACC in aggressive socially aggressive mice. Moreover, the present study suggested that the anti-aggressive effect of Topiramate could be related to its neuroprotective effects against the structural alterations of ACC.

The effect of acute topiramate administration on morphine withdrawal syndrome and brain-derived neurotrophic factor in central nervous system.

OBJECTIVES: Nucleus accumbens plays an important role in opioid addiction. Topiramate, increases postsynaptic gamma-aminobutyric acid receptor activity and antagonizes glutamatergic activity. Brain-derived neurotrophic factor (BDNF), which plays a key role in synaptic plasticity, is produced from proBDNF. The aim of this study is to investigate the effects of 100 µM topiramate applied into the lateral ventricle or nucleus accumbens on naloxone-induced morphine withdrawal and the BDNF/proBDNF ratio in the frontal cortex. METHODS: In the study, 36 adult male Wistar rats weighing 250-350 g were used. Morphine dependence was created with morphine pellets following guide cannula implantations. Withdrawal findings were evaluated in naloxone-induced morphine withdrawal syndrome following topiramate administration, and locomotor activity measurements were performed simultaneously. The brains of sacrificed animals were removed for determination of BDNF/proBDNF ratio. RESULTS: Topiramate administered by either route significantly suppressed the number of jumps in morphine withdrawal. Topiramate applied into the nucleus accumbens significantly reduced stereotypical behavior in morphine withdrawal, but did not cause any changes in other locomotor activity behaviors. Topiramate applied into the lateral ventricle significantly decreased the BDNF/proBDNF ratio, whereas administered into the nucleus accumbens significantly increased this ratio. CONCLUSION: The findings of this study indicate that topiramate administered into the lateral ventricle and nucleus accumbens reduces naloxone-induced morphine withdrawal symptoms, stereotypical locomotor activity, and changes the BDNF/proBDNF ratio.

Short-term topiramate treatment prevents radiation-induced cytotoxic edema in preclinical models of breast-cancer brain metastasis.

BACKGROUND: Brain edema is a common complication of brain metastases (BM) and associated treatment. The extent to which cytotoxic edema, the first step in the sequence that leads to ionic edema, vasogenic edema, and brain swelling, contributes to radiation-induced brain edema during BM remains unknown. This study aimed to determine whether radiation-associated treatment of BM induces cytotoxic edema and the consequences of blocking the edema in preclinical models of breast-cancer brain metastases (BCBM). METHODS: Using in vitro and in vivo models, we measured astrocytic swelling, trans-electric resistance (TEER), and aquaporin 4 (AQP4) expression following radiation. Genetic and pharmacological inhibition of AQP4 in astrocytes and cancer cells was used to assess the role of AQP4 in astrocytic swelling and brain water intake. An anti-epileptic drug that blocks AQP4 function (topiramate) was used to prevent cytotoxic edema in models of BM. RESULTS: Radiation-induced astrocytic swelling and transient upregulation of AQP4 occurred within the first 24 hours following radiation. Topiramate decreased radiation-induced astrocytic swelling and loss of TEER in astrocytes in vitro, and acute short-term treatment (but not continuous administration), prevented radiation-induced increase in brain water content without pro-tumorigenic effects in multiple preclinical models of BCBM. AQP4 was expressed in clinical BM and breast-cancer cell lines, but AQP4 targeting had limited direct pro-tumorigenic or radioprotective effects in cancer cells that could impact its clinical translation. CONCLUSIONS: Patients with BM could find additional benefits from acute and temporary preventive treatment of radiation-induced cytotoxic edema using anti-epileptic drugs able to block AQP4 function.

Genome-wide DNA methylation analysis in an antimigraine-treated preclinical model of cortical spreading depolarization.

BACKGROUND: Cortical spreading depolarization, the cause of migraine aura, is a short-lasting depolarization wave that moves across the brain cortex, transiently suppressing neuronal activity. Prophylactic treatments for migraine, such as topiramate or valproate, reduce the number of cortical spreading depression events in rodents. OBJECTIVE: To investigate whether cortical spreading depolarization with and without chronic treatment with topiramate or valproate affect the DNA methylation of the cortex. METHODS: Sprague-Dawley rats were intraperitoneally injected with saline, topiramate or valproate for four weeks when cortical spreading depolarization were induced and genome-wide DNA methylation was performed in the cortex of six rats per group. RESULTS: The DNA methylation profile of the cortex was significantly modified after cortical spreading depolarization, with and without topiramate or valproate. Interestingly, topiramate reduced by almost 50% the number of differentially methylated regions, whereas valproate increased them by 17%, when comparing to the non-treated group after cortical spreading depolarization induction. The majority of the differentially methylated regions lay within intragenic regions, and the analyses of functional group over-representation retrieved several enriched functions, including functions related to protein processing in the cortical spreading depolarization without treatment group; functions related to metabolic processes in the cortical spreading depolarization with topiramate group; and functions related to synapse and ErbB, MAPK or retrograde endocannabinoid signaling in the cortical spreading depolarization with valproate group. CONCLUSIONS: Our results may provide insights into the underlying physiological mechanisms of migraine with aura and emphasize the role of epigenetics in migraine susceptibility.

Eficacia y seguridad de lacosamida como tratamiento complementario en pacientes pediátricos con epilepsia focal refractaria / Efficacy and safety of lacosamide as adjunctive treatment in pediatric patients with refractory focal epilepsy

ANTECEDENTES: En el marco de la metodología ad hoc para evaluar solicitudes de tecnologías sanitarias, aprobada mediante Resolución de Institución de Evaluación de Tecnologías en Salud e Investigación N° 97-IETSI-ESSALUD-2022, se ha elaborado el presente dictamen que expone la evaluación de la eficacia y seguridad de lacosamida para el tratamiento de pacientes pediátricos con epilepsia focal refractaria. Así, el médico Dr. Edwin Martín Lazo Rivera, especialista en neurología pediátrica del Hospital Nacional Carlos Alberto Seguín Escobedo - Red Asistencial Arequipa y la Dra. Rebeca Fiorella Valdivia Bravo, especialista en pediatría del Hospital Nacional Alberto Sabogal Sologuren de la Red Prestacional Sabogal, siguiendo la Directiva N° 003-IETSI-ESSALUD-2016, enviaron al Instituto de Evaluación de Tecnologías en Salud e Investigación ­ IETSI sus respectivas solicitudes de autorización de uso del producto farmacéutico lacosamida no incluido en el Petitorio Farmacológico de EsSalud. ASPECTOS GENERALES: La epilepsia es una condición del sistema nervioso central caracterizada por crisis epilépticas recurrentes y no provocadas por desencadenantes inmediatos identificables. Así, la crisis epiléptica es aquel acontecimiento transitorio de signos y/o síntomas originados por una actividad neuronal cerebral sincrónica anormal o excesiva, que puede manifestarse por fenómenos sensitivos, motores, sensoriales o autonómicos con o sin pérdida de la conciencia, ya que dependen del área cerebral donde se originan. En ese sentido, las crisis convulsivas se clasifican según tres posibilidades de origen: las de inicio focal, generalizado y desconocido. Las crisis focales, a su vez, se pueden subclasificar en aquellas que tienen pérdida o no de la consciencia, para posteriormente categorizar si los síntomas son motores o no motores. En consecuencia, los especialistas deciden el abordaje terapéutico de los pacientes con epilepsia focal teniendo en cuenta esta clasificación, adicional a la etiología y a las comorbilidades asociadas (Reséndiz-Aparicio et al.,2019, Fisher et al.,2017, INSN.,2020). En todo el mundo, la epilepsia afecta aproximadamente a 65 millones de personas, reportándose una incidencia de la epilepsia de 67,8 por 100 000 habitantes en los países en desarrollo (Mohammadzadeh et al., 2022). En el Perú, se estima que la prevalencia de epilepsia es de 11,9 a 32,1 por cada 1000 personas (Burneo et al., 2017). Asimismo, es conocido que la incidencia de la epilepsia en la población pediátrica es de aproximadamente 0,5 % a 1 % de la población general. Además, algunos estudios sugieren que hasta el 60 % de los pacientes pediátricos con epilepsia presentarán remisión de su condición, mientras que alrededor del 20 % a 30 % de los pacientes con epilepsia serán refractarios al tratamiento médico (Ortiz de la Rosa et al., 2015). METODOLOGÍA: La búsqueda bibliográfica exhaustiva se llevó a cabo con el objetivo de identificar la mejor evidencia disponible sobre la eficacia y seguridad de lacosamida para el tratamiento de pacientes pediátricos con epilepsia focal refractaria a los FAE disponibles en EsSalud. La búsqueda bibliográfica se realizó en las bases de datos PubMed, The Cochrane Library. Web of Science y LILACS. Adicionalmente, se amplió la búsqueda revisando la evidencia generada por grupos internacionales que realizan revisiones sistemáticas (RS), evaluaciones de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC) de: la National Institute for Health and Care Excellence (NICE), la American Academy of Neurology (ANN), la American Epilepsy Society (AES), la Scottish Intercollegiate Guidelines Network (SIGN), la Internacional Database of GRADE Guideline (BIGG), la Canadian Agency for Drugs and Technologies in Health (CADTH), la Comissáo Nacional de Incorporadáo de Tecnologias no Sistema Único de Saúde (CONITEC) y el Ministerio de Salud del Perú (MINSA). Adicionalmente, se realizó una búsqueda manual en las bases el portal de la Base Regional de Informes de Evaluación de Tecnologías en Salud de las Américas (BRISA), y el repositorio institucional de la Dirección General de Medicamentos, Insumos y Drogas (DIGEMID). Finalmente, se realizó una búsqueda en el portal ClinicalTrials.govdel National Institutes of Health (NIH) para identificar ensayos clínicos en desarrollo o que aún no hayan sido publicados. La metodología de tipo escalonada fue utilizada para la selección de documentos a ser incluidos en el presente dictamen. De acuerdo con los criterios de elegibilidad, se priorizaron durante la selección: GPC, ETS, RS de ensayos clínicos (EC) con o sin metaanálisis (MA), y ensayos clínicos aleatorizados (ECA) de fase III. Se elaboraron estrategias de búsqueda sensibles en bases de datos bibliográficas y sitios web para obtener la evidencia científica que permita responder a la pregunta PICO. Las estrategias de búsqueda incluyeron términos relacionados con la intervención y población de interés. Se emplearon términos MeSH4, así como términos de lenguaje libre, junto con operadores booleanos para cada una de las bases de datos elegidas para la búsqueda. Los registros obtenidos de la búsqueda bibliográfica fueron importados al aplicativo web Rayyan (http://rayyan.qcri.org/) para una revisión manual por título y resumen. La selección de los estudios se realizó en una primera fase por dos evaluadores del Equipo Técnico del IETSI de manera independiente (búsqueda par); evaluando los títulos y resúmenes en relación con la pregunta PICO y seleccionando aquellos que serían evaluados a texto completo en una segunda fase por un único evaluador. En la segunda fase, uno de los evaluadores revisó los documentos a texto completo incluidos en la primera fase y realizó la selección final de los estudios. RESULTADOS: Luego de la búsqueda bibliográfica, se incluyó una GPC elaborada por la National Institute for Health and Care Excellence (NICE 2022), y un ECA de fase III, NCT01921205 (Farkas et al., 2019). CONCLUSIÓN: Por lo expuesto, el Instituto de Evaluación de Tecnologías en Salud e Investigación aprueba el uso de lacosamida para el tratamiento complementario en pacientes pediátricos con epilepsia focal refractaria, como producto farmacéutico no incluido en el Petitorio Farmacológico de EsSalud, según lo establecido en el Anexo N° 1. La vigencia del presente informe preliminar es de un año a partir de la fecha de publicación. Así, la continuación de dicha aprobación estará sujeta a la evaluación de los resultados obtenidos y de mayor evidencia que pueda surgir en el tiempo.

A Bayesian meta-analysis of topiramate's effectiveness for individuals with alcohol use disorder.

BACKGROUND: Topiramate (TPM) has the potential to become one of the most prominent treatment options for alcohol use disorder (AUD). We investigated the efficacy of TPM for AUD treatment, considering new randomized controlled trials carried out since the publication of four prior investigations. METHODS: We searched six major databases, comparing TPM to placebo for AUD treatment. We performed a Bayesian meta-analysis. We conducted a meta-regression, analyzing the effect of age, TPM dosage, duration of treatment, gender, and attrition rate on the outcomes measured. The protocol is registered with PROSPERO: CRD42021286266. RESULTS: TPM reduced heavy drinking days (d = 0.401, Bayes factor (BF) = 23.088) and weeks (d = 0.461, BF = 3.784), lowered alcohol craving (d = 0.477, BF = 107.749), prolonged abstinence throughout the duration of trials (d = 0.505, BF = 54.998), and decreased the amount of gamma-glutamyl transferase in the blood (d = 0.345, BF = 39.048). The analysis pointed out that TPM could reduce anxiety (d = 0.517, BF = 5.993). TPM's efficacy in relieving alcohol withdrawal, minimizing relapse, and decreasing depressive symptoms was inconclusive. There was evidence of a meta-regression effect of attrition rate on heavy drinking days and craving and length of treatment on abstinence. CONCLUSION: TPM has the potential to become a key pharmacological agent in the treatment of AUD.

Erenumab versus topiramate: post hoc efficacy analysis from the HER-MES study.

OBJECTIVE: HER-MES was the first head-to-head, phase 4 trial to assess the tolerability and effectiveness of erenumab against standard of care treatment (topiramate). This post hoc analysis compared the efficacy of erenumab with topiramate in patients who completed the trial on study medication. METHODS: Post hoc sensitivity analysis was performed using the full analysis set. Outcomes assessed included the proportion of patients with a ≥50% reduction in monthly migraine days (MMD) from baseline (50% responder rate), over the last 3 months (months 4, 5, and 6) of the double-blind treatment phase (DBTP), the 50% responder rate during the first month of the DBTP, and change from baseline in MMD during the DBTP. Multiple imputation was done for efficacy values of patients who discontinued study treatment. RESULTS: Patients (N = 777) were randomly assigned (1:1) to either 70 or 140 mg/month erenumab (N = 389) or 50-100 mg/day topiramate (N = 388). Of these, 334 patients (85.9%) receiving erenumab, and 231 patients (59.5%) receiving topiramate completed the DBTP on study medication. Patients on study medication until the end of the DBTP received a mean dose of 119 mg/month for erenumab and 92 mg/day for topiramate. At month 1, a significantly greater proportion of patients receiving erenumab (39.2%) reported ≥50% reduction in MMD from baseline compared with those receiving topiramate (24.0%; p < 0.001). In the last 3 months, a significantly larger proportion of patients receiving erenumab (60.3%) achieved ≥50% reduction in MMD from baseline compared with those receiving topiramate (43.3%; p < 0.001). Patients receiving erenumab demonstrated significantly greater reductions in MMD during the last 3 months from baseline versus those receiving topiramate (- 6.13 vs - 4.90; 95% CI: - 1.87 to - 0.61; p < 0.001). CONCLUSIONS: This post hoc analysis demonstrated significantly superior efficacy of erenumab versus topiramate in achieving a ≥50% reduction in MMD with an early onset of efficacy. TRIAL REGISTRATION: ClinicalTrials.gov NCT03828539 .