Topiramate and adrenocorticotropic hormone (ACTH) as initial treatment for infantile spasms

Clinical profile, treatment modalities, and outcomes in patients with infantile spasms: A retrospective study from the United Arab of Emirates (UAE)

BACKGROUND

Infantile spasms (IS) are an epileptic encephalopathy where the prognosis is generally poor, with most patients exhibiting psychomotor retardation or intractable epilepsy. However, it is claimed that early and aggressive treatment is related to better response rate and outcome, especially in patients with idiopathic IS.

OBJECTIVE

To investigate different treatment modalities and outcomes in patients with IS attending a pediatric neurology clinic at a specialized neurology center in Abu Dhabi, United Arab Emirates.

METHODS

Retrospective chart review was done for detailed history, demographic data, etiology, neuro-diagnostic workup, treatment modalities, and the outcomes for all patients diagnosed with IS from September 2014 to September 2019.

RESULTS

Three treatment modalities were identified as 1st line- Prednisolone United Kingdom Infantile Spasms Study (UKISS) (N = 15, 46.8%), Anti-Seizure Medications (ASMs) (N = 12, 37.5%), and Vigabatrin (N = 5, 15.6%). The complete response rate to Vigabatrin as a 1st line treatment showed the highest statistical significance (X² = 7.34, p = 0.007). Patients with idiopathic IS showed a comparable response to treatment to those with symptomatic IS. Additional response to 2nd line treatment with Prednisolone UKISS protocol (25%) and Vigabatrin (15%) was noted in patients who showed partial or no response to the 1st line treatment. None of our patients received Adrenocorticotropic Hormone as treatment. All patients with desirable final outcomes were with idiopathic IS and none were symptomatic.

CONCLUSION

More than a third of our patients showed poor treatment response whenever they were not offered treatment according to the current available protocols. This indicates an urgent need for having a unified treatment protocol that takes into consideration the availability of medications, professional expertise as well as diagnostic workup outside major tertiary care centers in our region.

Trends and Costs Associated With the Diagnosis and Treatment of Infantile Spasms: A 10-Year Multicenter Retrospective Review

OBJECTIVE

Early treatment of infantile spasms (IS) may be imperative for improvement of neurodevelopmental outcomes. Existing studies have led to inconclusive recommendations with variation in treatment. Our objective was to determine the national average cost, initial diagnostic workup, treatments, and hospital length of stay for patients with IS.

METHODS

This retrospective cohort study was designed to review data of patients < 2 years from 43 non-profit institutions. Data obtained included patient demographics, length of stay, admission cost, and treatments used from 2004 to 2014. Cost data were collected and adjusted to 2014 dollars, the year data were analyzed.

RESULTS

A total of 6183 patients met study criteria (n = 3382, 55% male). Three-quarters of patients (n = 4684, 76%) had an electroencephalogram, 56.4% had brain imaging (n = 3487), and 17% (n = 1050) underwent a lumbar puncture. Medication for IS was initiated during inpatient hospital stay in two-thirds of all patients (n = 4139, 67%). Most patients were initiated on corticotropin (n = 2066, 33%) or topiramate (n = 1804, 29%). Average length of stay was 5.8 days with an average adjusted cost of $18,348. Over time there was an 86.6% increase in cost from an average $12,534.54 (2004) to $23,391.20 (2014), a significant change (p < 0.01). This correlated with an increase in average length of stay.

CONCLUSIONS

Variability exists in diagnostic workup and pharmacotherapy initiated for IS, which may lead to differences in the cost of hospital stay. Further studies may help determine contributing factors to increased cost and improve health care utilization for IS patients.

Isovaline efficacy in a rat pup model of infantile spasms

Infantile spasms, also known as epileptic spasms during infancy, is an epileptic disorder of infancy and early childhood that is associated with developmental delay or regression, high mortality rate and is difficult to treat with conventional antiseizure medication. Previously, we reported that a unique amino acid called isovaline had potent anticonvulsive efficacy in the 4-aminopyridine and pilocarpine rat models of seizures. In this study, we examined whether isovaline possess therapeutic utility in a well-established rat model of infantile spasms which involves the pretreatment of a pregnant dam with betamethasone and subsequent induction of spasms with N-methyl-D-asparate (NMDA), a glutamate receptor agonist, in 15-day old pups. We treated seven of these pups with saline prior to administering NMDA and eight of these pups with isovaline (300 mg/kg) intraperitoneal (i.p.) prior to NMDA. Isovaline significantly reduced the number of full-body jumps from 18.1 ± 5.0 to 6.3 ± 1.8 and leg/arm/tail strains from 4.4 ± 1.6 to 1.1 ± 0.5. A trend in a reduction of body twitch was noted in rat pups administered isovaline (P = 0.05), but no significant difference was seen in NMDA-induced head nods (P = 0.221). In conclusion, our data demonstrate a potential for isovaline to attenuate an aggressive form of epilepsy that typically requires highly toxic medications to treat in children.

Efficacy of Treatments for Infantile Spasms: A Systematic Review

OBJECTIVES

West syndrome (also known as infantile spasm because of its main seizure type) is a rare form of epilepsy that begins during early infancy. Recent guidelines and reviews on West syndrome recommend the use of adrenocorticotropic hormone steroids, or vigabatrin, as the first-line treatment. However, West syndrome remains to be one of the most challenging epilepsies to treat. Here, we systematically reviewed the current literature obtained during the previous decade. This article provides an overview of the current treatment of infantile spasms.

METHODS

PubMed and EMBASE were searched to retrieve studies on human published during 2005-2015 and to identify patients with clinical diagnosis of infantile spasms. Drug or diet treatments were used as interventions and comparators.

RESULTS

We included 55 studies, of which 1 study was a meta-analysis, 9 were randomized controlled trials, 21 were prospective studies, and 24 were retrospective studies. Topiramate, levetiracetam, zonisamide, and sodium valproate with benzodiazepine (clonazepam or nitrazepam) were found to be potential drugs for treating West syndrome besides adrenocorticotropic hormone, steroids, and vigabatrin. Ketogenic diet and modified Atkins diet were also found to be effective.

CONCLUSIONS

To date, data regarding the efficacy of treatments of West syndrome still remain limited. Some treatments, including topiramate and ketogenic diet, seem promising besides adrenocorticotropic hormone, steroids, and vigabatrin. Well-designed trials are warranted to validate the findings.

Improving Outcomes in Infantile Spasms: Role of Pharmacotherapy

Infantile spasms, and specifically within the context of West syndrome , is one of the most common epileptic encephalopathies to occur in early infancy. Early recognition and treatment can improve neurodevelopmental outcome in some cases, although the underlying aetiology is probably the most important prognostic factor in both spasm suppression and developmental outcome. Corticosteroids, either adrenocorticotrophic hormone (ACTH) or prednisolone, and vigabatrin are currently the preferred first-line treatment options. Vigabatrin is the treatment of choice when the underlying cause is tuberous sclerosis complex (TSC). Emerging evidence suggests that a combination of steroid and vigabatrin may be more effective in the suppression of spasms and resolution of hypsarrhythmia, the electro-encephalographic signal of spasms. Several other anti-epileptic drugs (AEDs) (levetiracetam, nitrazepam, sodium valproate, topiramate, zonisamide) are usually used as add-on or adjunctive treatment in refractory cases. Pyridoxine (or pyridoxal phosphate) and the ketogenic diet are established treatment options in refractory cases. There is some evidence that neuro-active steroids, including ganaxolone, may be effective; however, clinical trials undertaken intermittently for over a decade have yet to prove their efficacy, not only for the suppression of infantile spasms but also for the resolution of hypsarrhythmia, which may be as important as seizure control in developmental outcome in these children. Insights into developing novel treatment options have emerged from rodent models of infantile spasms, and research is continuing into the efficacy of rapamycin in improving outcomes in infantile spasms. This review provides a brief overview of the existing scientific literature around treatment options and outlines emerging newer treatment options in infantile spasms.

Management of infantile spasms

West syndrome, or infantile spasms syndrome is a frequently catastrophic infantile epileptic encephalopathy with a variety of etiologies. Despite the heterogeneous nature of causes of infantile spasms, a careful diagnostic evaluation can lead to diagnosis in many patients and may guide treatment choices. Magnetic resonance imaging (MRI) brain remains the highest yield initial study in determining the etiology in infantile spasms. Treatment of infantile spasms has little class I data, but adrenocorticotropic hormone (ACTH), prednisolone and vigabatrin have the best evidence as first-line medications. Other therapies including the ketogenic diet and other anti-epileptics medications may also prove useful in the treatment of infantile spasms. In general, more studies are needed to determine the best treatment regimen for this condition. Prognosis is generally poor, with the majority of patients having some or profound neurocognitive delays. Patients without delays at diagnosis and without an identifiable etiology, if treated appropriately, have the greatest likelihood of a normal outcome.

Infantile Spasms Respond Poorly to Topiramate

INTRODUCTION

Infantile spasms are seizures typical of an age-related epileptic encephalopathy. Although evidence supporting topiramate for infantile spasms is lacking, many clinicians use it for this indication. The aim of this study was to determine the rate of infantile spasm remission with topiramate at our institution. A low rate of infantile spasm remission was hypothesized.

METHODS

This was a single-center retrospective medical record review of patients treated with topiramate for infantile spasms between January 2009 and September 2013. Records were reviewed for accuracy of diagnosis and outcome. Clinical remission of infantile spasms was defined as resolution for at least 28 days at any time during treatment with topiramate. For patients with clinical remission, posttreatment electroencephalographs were reviewed to assess for electrographic remission. To assess for confounding variables affecting remission rate, demographics and outcomes were compared with patients treated with adrenocorticotropic hormone within the same period using the same criteria for remission.

RESULTS

Three of 31 (9.7%) patients achieved clinical remission with topiramate, two of whom also experienced electrographic remission. The third patient had electrographic remission with previous adrenocorticotropic hormone treatment but infantile spasm remission only after receiving topiramate. All three of these patients experienced subsequent electroclinical relapse during topiramate therapy. Although there were no significant demographic differences between the topiramate and adrenocorticotropic hormone cohorts, more adrenocorticotropic hormone patients achieved clinical remission (9.7% versus 56%; P < 0.001).

DISCUSSION

Remission of infantile spasms with topiramate was uncommon and no patient experienced persistent electroclinical remission. These findings suggest that infantile spasms respond poorly to topiramate.

Infantile spasms syndrome, West syndrome and related phenotypes: what we know in 2013

The current spectrum of disorders associated to clinical spasms with onset in infancy is wider than previously thought; accordingly, its terminology has changed. Nowadays, the term Infantile spasms syndrome (ISs) defines an epileptic syndrome occurring in children younger than 1 year (rarely older than 2 years), with clinical (epileptic: i.e., associated to an epileptiform EEG) spasms usually occurring in clusters whose most characteristic EEG finding is hypsarrhythmia [the spasms are often associated with developmental arrest or regression]. The term West syndrome (WS) refers to a form (a subset) of ISs, characterised by the combination of clustered spasms and hypsarrhythmia on an EEG and delayed brain development or regression [currently, it is no longer required that delayed development occur before the onset of spasms]. Less usually, spasms may occur singly rather than in clusters [infantile spasms single-spasm variant (ISSV)], hypsarrhythmia can be (incidentally) recorded without any evidence of clinical spasms [hypsarrhythmia without infantile spasms (HWIS)] or typical clinical spasms may manifest in absence of hypsarrhythmia [infantile spasms without hypsarrhythmia (ISW)]. There is a growing evidence that ISs and related phenotypes may result, besides from acquired events, from disturbances in key genetic pathways of brain development: specifically, in the gene regulatory network of GABAergic forebrain dorsal-ventral development, and abnormalities in molecules expressed at the synapse. Children with these genetic associations also have phenotypes beyond epilepsy, including dysmorphic features, autism, movement disorders and systemic malformations. The prognosis depends on: (a) the cause, which gives origin to the attacks (the complex malformation forms being more severe); (b) the EEG pattern(s); (c) the appearance of seizures prior to the spasms; and (d) the rapid response to treatment. Currently, the first-line treatment includes the adrenocorticotropic hormone ACTH and vigabatrin. In the near future the gold standard could be the development of new therapies that target specific pathways of pathogenesis. In this article we review the past and growing number of clinical, genetic, molecular and therapeutic discoveries on this expanding topic.

Randomised clinical efficacy trial of topiramate and nitrazepam in treatment of infantile spasms

OBJECTIVE

Infantile spasms (IS) are among the most catastrophic epileptic syndromes of infancy. The purpose of this study was to compare efficacy and safety of topiramate (TPM) and nitrazepam (NZP) as first-line drugs in the treatment of IS.

MATERIALS & METHODS

In a parallel single-blinded randomized clinical trial, 50 patients with IS referred to Pediatric Neurology Clinic of Shahid Sadoughi University of Medical Sciences, Yazd, Iran, were evaluated from September 2008 to March 2010. Patients were randomly assigned to two groups to be treated with TPM or with NZP for 6 months. The primary endpoint was efficacy in cessation of all spasms or reduction of more than 50% in weekly seizure frequency, which was evaluated before and 6 months after the drug use. Secondary outcome was clinical sideeffects of the drugs.

RESULTS

Twenty boys (40%) and 30 girls (60%) with the mean age of 9.4±3.8 months were evaluated. Cessation of all spasms occurred in 12 (48%) infants in TPM group and 4(16%) in NZP group. Eight (32%) children in TPM group and 7 (28%) in NZP group had more than 50% reduction in spasms frequency. So, TPM was more effective. Side effects were seen in 32% of TPM and in 36% of NZP groups.

CONCLUSION

Topiramate is an effective and safe drug, which might be considered as the firstline drug for the treatment of ISs.

An effective initial polytherapy for children with West syndrome

Adrenocorticotropic hormone is recommended worldwide as an initial therapy for infantile spasms. However, infantile spasms in about 50% of children cannot be fully controlled by adrenocorticotropic hormone monotherapy, seizures recur in 33% of patients who initially respond to adrenocorticotropic hormone monotherapy, and side effects are relatively common during adrenocorticotropic hormone treatment. Topiramate, vitamin B₆, and immunoglobulin are effective in some children with infantile spasms. In the present study, we hypothesized that combined therapy with adrenocorticotropic hormone, topiramate, vitamin B₆, and immunoglobulin would effectively treat infantile spasms and have mild adverse effects. Thus, 51 children newly diagnosed with West syndrome including infantile spasms were enrolled and underwent polytherapy with the four drugs. Electroencephalographic hypsarrhythmia was significantly improved in a majority of patients, and these patients were seizure-free, had mild side effects, and low recurrence rates. The overall rates of effective treatment and loss of seizures were significantly higher in cryptogenic children compared with symptomatic children. The mean time to loss of seizures in cryptogenic children was significantly shorter than in symptomatic patients. These findings indicate that initial polytherapy with adrenocorticotropic hormone, topiramate, vitamin B₆, and immunoglobulin effectively improves the prognosis of infantile spasms, and its effects were superior in cryptogenic children to symptomatic children.

West syndrome: response to valproate

Management of West syndrome is unsatisfactory. In our clinic we observed that a significant proportion of patients respond to usual dose of valproate. Objective: To prospectively assess the efficacy of valproate in controlling infantile spasms in West syndrome. Methods: Consecutive patients presenting with West syndrome to the Pediatric Neurology Clinic or general outpatient department (OPD) were enrolled for study. Those who were not on any treatment were given valproate in a dose of 30 mg/kg/day while awaiting investigations. Patients were followed up every 2 weeks. Predefined criteria for definition of West syndrome and response were used. Those showing partial/poor response or relapse on valproate were given hormonal therapy. Results: One hundred children with West syndrome were enrolled. Ninety one children were started on valproate. Of these 36 (39.5%) showed a good response, but seven later relapsed while on same dose of valproate and three were lost to follow up. Later age at onset and typical hypsarrhythmia on EEG were associated with good sustained response to valproate while a history of delayed cry at birth was associated with partial or poor response. Sixty two patients who responded poorly to or relapsed on valproate were put on hormonal treatment in addition. Of these 36 (58.1%) had a good response but 11 later relapsed after stopping treatment and two were lost to follow up. Conclusion: Valproate may have a role in treatment of West syndrome in a selected group of patients.

The current evaluation and treatment of infantile spasms among members of the Child Neurology Society

The optimal evaluation and treatment of children with infantile spasms is unknown. To aid in the development of a standardized approach to infantile spasms, members of the Child Neurology Society were surveyed to determine common practice. The survey had 222 responders with a responder rate of 18.5%. We found that the diagnostic evaluation and the use of first-line treatments varied among responders. For example, although adrenocorticotropic hormone continues to be the most commonly used first-line treatment for infantile spasms not due to tuberous sclerosis, some clinicians use corticosteroids, vigabatrin, and topiramate as first-line treatments for this group. Seventy percent of our responders reported seeing fewer than 10 new-onset cases of infantile spasms per year. Thus, future clinical trials will require multicenter collaboration. An important first step in such collaboration is to standardize the evaluation and treatment of infantile spasms within and between participating centers.

Short term outcomes of topiramate monotherapy as a first-line treatment in newly diagnosed West syndrome

Purpose

To investigate the efficacy of topiramate monotherapy in West syndrome prospectively.

Methods

The study population included 28 patients (15 male and 13 female children aged 2 to 18 months) diagnosed with West syndrome. After a 2-week baseline period for documentation of the frequency of spasms, topiramate was initiated at 2 mg/kg/day. The dose was increased by 2 mg/kg every week to a maximum of 12 mg/kg/day. Clinical assessment was based on the parents' report and a neurological examination every 2 weeks for the first 2 months of treatment. The baseline electroencephalograms (EEGs) were compared with the post-treatment EEGs at 2 weeks and 1 month.

Results

West syndrome was considered to be cryptogenic in 7 of the 28 patients and symptomatic in 21 patients. After treatment, 11 patients (39%) became spasm-free, 6 (21%) had more than 50% spasmsreduction, 3 (11%) showed less than 50% reduction, and 8 (29%) did not respond. The effective daily dose for achieving more than 50% reduction in spasm frequency, including becoming spasm-free, was found to be 5.8±1.1 mg/kg/day. Nine patients (32%) showed complete disappearance of spasms and hypsarrhythmia, and 11 (39%) showed improved EEG results. Despite adverse events (4 instances of irritability, 3 of drowsiness, and 1 of decreased feeding), no patients discontinued the medication.

Conclusion

Topiramate monotherapy seems to be effective and well tolerated as a first line therapy for West syndrome and is not associated with serious adverse effects.

Topiramate for the treatment of neonatal seizures

Therapeutic options for treating neonatal seizures, such as phenobarbital and phenytoin, lack efficacy and are potentially harmful to the developing brain. Topiramate appears effective as both an antiseizure and neuroprotective agent in animal models of newborn brain injury. Although topiramate is a common add-on agent in newborns, its use in this population has not yet been reported. We performed a retrospective cohort study of clinical topiramate use in newborns with acute symptomatic seizures that were refractory to standard agents. In four of six newborns, apparent reduction or no further seizures occurred. None of the children experienced side effects resulting in discontinuation of the drug, either during the hospital admission or after discharge. Prospective studies evaluating the safety and efficacy of topiramate for both seizures and neuroprotection will be important in determining whether it deserves widespread use in clinical practice.