Intravenous lacosamide in seizure emergencies: Observations from a hospitalized in-patient adult population

Accepted Manuscript Title: INTRAVENOUS LACOSAMIDE IN SEIZURE EMERGENCIES: OBSERVATIONS FROM A HOSPITALIZED IN-PATIENT ADULT POPULATION Author: Giuseppe d’Orsi Maria Grazia Pascarella Tommaso Martino Elena Carapelle Francesca Pacillo Maria Teresa Di Claudio Daniela Mancini Marina Trivisano Carlo Avolio Luigi M. Specchio PII: DOI: Reference:

S1059-1311(16)30151-0 http://dx.doi.org/doi:10.1016/j.seizure.2016.09.004 YSEIZ 2788

To appear in:

Seizure

Received date: Revised date: Accepted date:

9-7-2016 5-9-2016 8-9-2016

Please cite this article as: d’Orsi G, Pascarella MG, Martino T, Carapelle E, Pacillo F, Claudio MTD, Mancini D, Trivisano M, Avolio C, Specchio LM, INTRAVENOUS LACOSAMIDE IN SEIZURE EMERGENCIES: OBSERVATIONS FROM A HOSPITALIZED IN-PATIENT ADULT POPULATION, SEIZURE: European Journal of Epilepsy (2016), http://dx.doi.org/10.1016/j.seizure.2016.09.004 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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INTRAVENOUS LACOSAMIDE IN SEIZURE EMERGENCIES: OBSERVATIONS FROM A HOSPITALIZED IN-PATIENT ADULT

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POPULATION.

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Giuseppe d’Orsi, Maria Grazia Pascarella, Tommaso Martino, Elena Carapelle, Francesca Pacillo, Maria Teresa Di Claudio, Daniela Mancini, Marina Trivisano1, Carlo Avolio, Luigi M. Specchio.

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Epilepsy Centre - Clinic of Nervous System Diseases, University of Foggia, Riuniti Hospital, Foggia, Italy. Department of Neurosciences, Neurology Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy; Clinic of Nervous System Diseases,

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University of Foggia, Riuniti Hospital, Foggia, Italy

Correspondence to:

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Giuseppe d’Orsi Epilepsy Centre

Clinic of Nervous System Diseases, University of Foggia A.O.U. Riuniti Hospital Via Luigi Pinto 1, 71100 Foggia. Italy. Tel.: 0039-0881/736125 Fax: 0039-0881/736389 E-mail: [email protected]

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Disclosure of Conflicts of Interest

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The authors have read the journal’s position on the issues involved in ethical publication and affirm that this report is consistent with those

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guidelines.

Disclosure: The authors have no conflicts of interest to declare.

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The study was not initiated, and not sponsored by UCB Pharma. Authors:

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Giuseppe d’Orsi: study concept and design, acquisition of data, analysis, interpretation analysis and interpretation of the manuscript. Maria Grazia Pascarella, Tommaso Martino, Elena Carapelle: acquisition of data, analysis and interpretation analysis of the manuscript.

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Francesca Pacillo, Maria Teresa Di Claudio, Daniela Mancini, Marina Trivisano, Carlo Avolio, Luigi M. Specchio: acquisition of data.

ABSTRACT

Purpose: to evaluate the efficacy and safety of intravenous (IV) lacosamide (LCM) in the treatment of seizure clusters (SC) and status epilepticus (SE) in hospitalized adult patients. Methods: we prospectively analyzed treatment response, seizure outcome, and adverse effects of IV LCM in thirty-eight patients with seizure emergencies (15 with SC, 23 with SE) during a hospital stay. The loading dose of IV LCM was 200 - 400 mg and the maintenance dose was 200 400 mg daily. Response to IV LCM was evaluated within 20 min, 4 h and 24 h of LCM infusion. Results: an acute anti-seizure effect after IV LCM was especially evident when it was first used - (SC) or second line (established SE) treatment. In particular, 87% of SC patients (13/15) and 80% of established SE (8/10) demonstrated response to LCM treatment, while no patients with superrefractory SE (0/8) responded to IV LCM according to our criteria. The loading of IV LCM was well tolerated, with mild adverse effects (2/38

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temporary dizziness). In most patients, during and after administration of the loading dose of IV LCM a temporary (30 min – 1 h) sedation was

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observed. No ECG and laboratory values-changes were documented in any of the patients. Conclusions: LCM is an effective and well-tolerated treatment when used to treat SC in hospitalized adult patients. As add-on therapy, it may be

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useful to stop seizure activity in patients with focal SE not responding to first/second-line intravenous AEDs.

INTRODUCTION

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Key-words: Lacosamide – Status epilepticus – Seizure Clusters –– Hospitalized adult population – Seizure Emergencies – Video-EEG monitoring

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Intravenous (IV) administration of antiepileptic drugs is useful in patients who are unable to take oral medication, and in emergency situations such

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as seizure clusters (SC), status epilepticus (SE), or when rapid introduction of a new agent is necessary because seizures are uncontrolled on baseline therapy. Lacosamide (LCM), a new anti-epileptic drug with a mechanism of action utilizing the slow inactivation of sodium channels1, is

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also available in an IV formulation. Several studies have showed the efficacy of IV LCM in patients with SC or SE. In particular, apart from a series of nine patients with refractory SE who showed no response to treatment with IV LCM2, the efficacy of IV LCM in SC and SE has been shown in most case reports and series with rates of 44-100%3-14. Nevertheless, all studies have often demonstrated several limitations, e.g. a) the studies were retrospectively collected and non-controlled cohort, or when evaluated prospectively, there was no randomization; b) the sample sizes were usually small; c) LCM was used at variable points in the course of SE, especially in the late stages of refractory SE or during super-refractory SE, without standardization in the order of LCM in the therapeutic algorithm; d) the definition of SC and SE, and, especially, of response to LCM might also have been lacking; e) experiences in seizure emergencies were usually limited to the heterogeneous patient population and treatment protocols.

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In view of the rapidly increasing literature that has described the efficacy of IV LCM in a range of heterogeneous clinical situations, we considered

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it appropriate to gain more experience of the use of this drug in the hospitalized in-patient adult population. The aim of our study was to evaluate the

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efficacy and safety of treatment with IV LCM in patients with emergency situations, initially in cases of super-refractory SE and subsequently in cases when it was used earlier (refractory and established SE, and SC).

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METHODS

We prospectively investigated thirty-eight patients with seizure emergencies (15 with SC, 23 with SE) who were consecutively presented to our

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neurological ward between June 2011 and November 2015, and received IV LCM; we also included eight patients with super-refractory SE who were again presented to our neurological ward, and subsequently recovered at an intensive care unit.

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A SC was defined as at least three seizures within a 24-h period15. SE was classified according to seizure semiology based on the proposal of the

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ILAE Task Force along with two taxonomic criteria: presence of motor symptoms and impairment of consciousness16. Hence, we distinguished between the following: (a) SE with prominent motor symptoms (including tonic–clonic SE, myoclonic SE, focal motor SE, tonic SE and hyperkinetic SE) and (b) SE without prominent motor symptoms (NCSE) with or without coma. With regard to etiology, we distinguished between idiopathic, symptomatic (acute, remote and progressive) and cryptogenic (unknown cause). Patients who did not respond to benzodiazepines were considered to be in established SE, while the refractory stage was considered when benzodiazepines and IV antiepileptic drugs (AEDs) have failed to control the seizures. Super-refractory SE was defined as persistent seizure activity for more than 24 h despite intravenous anaesthetics17. The diagnosis of seizure emergencies was made clinically and using video-electroencephalogram (EEG) and polygraphic monitoring. In particular, video-EEG and polygraphic monitoring was used to characterize the SE, monitor response to treatment and confirm cessation of SE. The recording

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video-EEG and polygraphic parameters included: video-EEG (electrodes placed according to the 10-20 International system with bipolar montage);

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electromyogram (EMG); EKG. The polygraphic EMG signals were recorded with pairs of surface electrodes with standard belly-tendon placement.

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The signals were acquired digitally (sampling frequency: 512 Hz; band pass filters: 1.6–210 Hz; MicroMed System, Mogliano Veneto, Italy). Video-EEG and polygraphic monitoring, lasting at least 6 h, and were performed before, during and after LCM administration. Patients

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subsequently underwent a video-EEG and polygraphic monitoring, lasting at least 2 h, after 6, 12 and 24 h; a video-EEG/polygraphic follow-up, lasting at least 2 h, was performed after 24 and 48 h from the resolution of emergency situations. The onset of the SC or SE was defined according

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to clinical history, the cessation as termination of clinical symptoms and of seizure activity in the video-EEG without recurrence during the same hospital stay.

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Response to IV LCM was defined as LCM being the last drug administered prior to SC or SE termination. Immediate SE resolution was considered

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if ictal clinical - EEG pattern ceased within 20 min following treatment and remained suppressed for 40 min18. Early SE resolution was defined as seizure termination occurring within 4 h of IV LCM administration without other AEDs administration; four hours was chosen because LCM maximum plasma concentration had been reached between 1 and 4 hours after intake19. Late SE resolution was defined as seizure termination occurring within 24 h of IV LCM administration without other AEDs administration. The protocol for administering IV LCM was as follows: i) LCM was given in an IV formulation over a period of 5 minutes, through a peripheral line, and was diluted in 50 ml of normal saline. ii) The loading dose of IV LCM was usually 200 mg and the maintenance dose was 200 mg daily. In 9 patients without rapid SE response, an additional 200 mg of LCM was infused after 15 min and the maintenance dose was 400 mg daily. Because the right dose and the infusion rate needed further clarification20, we utilized the splitting of the dose of LCM into two infusions of 200 mg to better characterize the efficacy. IV LCM was

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administered as first-line treatment in SC, as second-line treatment (generally, after IV lorazepam or IV diazepam) in established SE, as third line

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treatment (generally, after benzodiazepine followed by PHT or LEV) in refractory SE; as fourth or fifth line treatment (after one or two AEDs plus

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benzodiazepine, and intravenous anaesthetics such as propofol or midazolam) in super-refractory SE. Blood samples including a hemogram, metabolic panel including electrolytes, blood urea nitrogen, creatinine, glucose, liver enzymes, and levels of concomitant AEDs were taken before

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infusion, 0–4 h post-infusion start, 12 h post-infusion, and 24 h post-infusion. All patients were under continuous cardiorespiratory monitoring at our neurological ward and intensive care unit. Information was collected on the following: underlying etiology, SC/SE type, SC/SE duration,

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number and sequence of other AEDs anticonvulsants used to treat the same seizure episode, response to IV LCM treatment, and adverse effects. Outcome after cessation of SE (termination of clinical symptoms or cessation of seizure activity in the EEG) was assessed according to the Glasgow

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weeks of SE).

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Outcome Scale (GOS) as follows: good recovery, moderate disability, severe disability, persistent vegetative state, and death (if it occurred within 8

The study was approved by the local ethics committee, and informed consent to participate in study was obtained by patients or parents. RESULTS

Table 1 and 2 summarize the demographics, clinical, Video-EEG/polygraphic, and emergency situations management data of the thirty-eight patients. Figures 1-3 showed an illustrative case with SE refractory responsive to IV LCM. SC Fifteen patients (8 men and 7 women), the mean age was 44.5 years (range 28-65). Approximately 70% had a diagnosis of epilepsy (often remote symptomatic), and with regard to semiology half of them presented with motor symptoms. Mean number of seizures within a 24-h period was 4

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(range 3-8), and mean SC duration was of 12 h (range 6-24 h). LCM was given after IV 10 mg diazepam in 5 patients; the loading dose of IV LCM

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was 200 mg and the maintenance dose was 200 mg daily. In 87% of the patients (n=13 patients) the SC resolved with IV LCM without adverse

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events. Two patients (ischemic stroke) did not respond, and in these patients SC evolved in SE responsive to phenytoin. Established SE

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Ten patients (3 men and 7 women), the mean age was 60 years (range 45-85). The aetiology was cryptogenic in two cases, symptomatic in seven patients (haemorrhagic stroke in two cases, progressive cerebral neoplasms - glioma - in two cases, metabolic in three cases), idiopathic generalized

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epilepsy presenting with absence SE in one patient20. In patients with cryptogenic and symptomatic aetiology SE was with prominent motor symptoms convulsive (six patient with de novo SE); SE

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duration was 12 h (range 6-14), LCM was given after diazepam and a median time of 8 h (range: 6–18); the loading dose of IV LCM was 200 mg

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and the maintenance dose was 200 mg daily. In eight patients IV LCM terminated the SE within 4 h after the first administration; in one patient (haemorrhagic stroke), IV LCM was without response according to our criteria. Instead, in the patient with idiopathic generalized epilepsy presenting with absence SE20 400 mg of IV LCM was not effective (after 24 h ASE spontaneously resolved). In two patients with established SE a temporary dizziness was observed; in all patients, during and after administration of the loading dose of IV LCM a temporary (30 min – 1 h) sedation was observed. No ECG and laboratory values-changes were documented. Outcomes after SE showed good recovery in all patients. Refractory SE Five patients (two men and three women), 55-76 years old (median 64 years). The aetiology was metabolic in two cases, progressive cerebral neoplasms (glioma) in two patients and a haemorrhagic stroke in one patient. All patients were found to have de novo SE with prominent motor

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symptoms convulsive (clonic and tonic-clonic). SE duration was from one to three days, LCM was given after a median number of two AEDs

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(diazepam, phenytoin or levetiracetam) and a median time of 1.5 days (range: 1–3). The loading dose of IV LCM was 200 mg and the maintenance

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dose was 200 mg daily. In four patients IV LCM terminated the SE within 20 min - 4 h after the first administration (immediate and early responses); in one patient with a haemorrhagic stroke and SE duration of three days, IV LCM was ineffective according to our criteria. No adverse

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events were observed; in most cases, during and after administration of the loading dose of IV LCM a temporary (30 min – 1 h) sedation was observed. No ECG and laboratory values-changes were documented. Outcomes after SE were good showing recovery in four patients, while one

Super-refractory SE

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patient died during an acute episode of SE from their underlying brain disease (haemorrhagic stroke).

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Eight patients (four men and four women), ranging in age from 33 to 80 years (median 58). The aetiology was cryptogenic in two cases, and

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symptomatic in six patients (haemorrhagic stroke in three cases, progressive cerebral neoplasms - glioma, brain metastasis - in two cases, limbic encephalitis in one case). Seven patients were found to have de novo SE with prominent motor symptoms (myoclonic and tonic-clonic), one patient had NCSE with coma. SE duration was from one to seven days in three patients and more than 7 days in five patients. LCM was given after a median number of four AEDs (range: 3–7) and a median time of 2.5 days (range: 2–17). The loading dose of IV LCM was usually 400 mg (splitting of the dose of LCM into two infusions of 200 mg) and the maintenance dose was 400 mg daily. No patients responded to IV LCM according to our criteria. No adverse events were observed and no ECG and laboratory values-changes were documented. 4/8 patients died during an acute episode of SE from their underlying brain disease, while 2/8 died during the same hospitalization from sepsis; there was moderate disability rate in 1/8 patient (limbic encephalitis: mild cognitive impairment associated with drug-resistant epilepsy).

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DISCUSSION

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LCM is mainly prescribed in outpatient epilepsy or neurology clinics. However, its favorable pharmacokinetic profile, good tolerability, possibility

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of fast titration and IV formulation suggest that it may be a very useful drug to use in hospitalized patients. LCM shows an antiepileptic activity in a large number of animal seizure models, including the model of SE: in the cobalt/homocysteine model for self-sustaining status epilepticus in rats,

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LCM blocked generalized tonic-clonic seizures, and this effect was markedly potentiated by co-administration of DZP21. Moreover, it also effectively terminates seizures in the rat performant path stimulation SE model when administered early after the onset of seizures22.

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The clinical efficacy of LCM in seizure emergencies (SC and SE) has been shown in several, often retrospective, studies or case reports with different efficacy rates, different criteria for the effectiveness of LCM in the termination of SE and SC, and often without a clear differentiation

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between different types of seizure emergencies. Following a pubmed literature search using the term “status epilepticus”, “seizure cluster”,

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“lacosamide”, we reviewed the use of LCM in emergency situations (see Table 3). We identified a total of 26 articles, 3 of which regarded people under 18 years of age. Among the adult population there were 12 retrospective single- or multi-center studies, 3 prospective single or multi-center studies, 6 case reports and 2 case series, for a total of 479 SE/SC episodes (478 people, 238 males and 240 females; age range was 17-95 years). Seizure termination was obtained in 310/479 episodes (64.72%), regardless of the type of epileptic emergency and of the latency between LCM first administration and status termination. Only three papers separately analyzed SC, with a cessation rate of 61/72 episodes (84.72%). Only three papers clearly defined super-refractory status epilepticus, for a total of 12 episodes and a cessation rate of 8/12 (66.67%). Adverse events were reported in 9/23 papers. Reported adverse events included: allergic skin reaction, sedation, hypotension, somnolence, nausea, dizziness, diplopia, blurred vision, vomiting, PR interval prolongation, AV block, nystagmus, acute angioedema. Time to termination of SE after the first administration

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of LCM vary widely, from 5 mins to 5 days, since the definition of the termination drug used in most of the papers is the last AED administered

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before SE cessation regardless of the latency between its first administration and SE cessation. Also dosage and route of administration vary

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between the papers, the most commonly used being iv bolus of 50-200 mg. Among children, three studies analyzed response in 46 children (27 males, 19 females, age range 1 month to 17 years). Overall the response rate was 31/46 (67.39%). Of all episodes, 4 were super-refractory with a

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response rate of zero; refractory SE were in total 19, with a response rate of 13/19 (68.42%). Although our study had an uncontrolled observational nature, a lack of randomization and a small number of patients, it still reflects everyday

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clinical practice in a tertiary hospital and can provide interesting information to neurologists and other physicians dealing with patients with seizure emergencies in a hospital setting. In particular, the main observations we experienced during our study were:

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1. An acute antiseizure effect after IV LCM was especially evident when it was used as first- (SC) or second line (established SE) treatment. In

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particular, 87% of SC patients (13/15) and 80% of established SE (8/10) in this study demonstrated response to LCM treatment, while no patients with super-refractory SE (0/8) responded to IV LCM according to our criteria. 2. The loading of IV LCM was well tolerated, with mild adverse effects. In particular, in most patients, during and after administration of the loading dose of IV LCM a temporary (30 min – 1 h) sedation was observed. No ECG and laboratory values-changes were documented in all patients. Our study shows its short-term safety and effectiveness to control seizures especially in patients with SC and who therefore need a drug with a rapid onset of action but have medical conditions, for example, in patients with seizures in the context of stroke, brain tumors, and hepatic disease (thirteen patients of fifteen patients with SC). Moreover, in patients with cryptogenic and symptomatic focal SE, not responding to a first or second

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AED, LCM can also be effectively used. The possibility of brain damage during prolonged focal SE23 has to be weighed against the possible

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complications of sedation requiring orotracheal intubation, especially in elderly patients. LCM seems a good option to try in these patients before

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proceeding to anesthetic drugs. In our series, it controlled ongoing seizures in four out of five patients with refractory SE and eight out of ten patients with established SE. Conversely, in one patient with idiopathic generalized epilepsy presenting with absence, SE IV LCM was not

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effective. The mechanism underlying the generation of absence seizures is due to an oscillatory activity within a corticothalamic network that depends on GABAergic systems, but especially T-type calcium channels24. Because LCM acts primarily by interfering with the slowly inactivating

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component of voltage gated sodium currents, we hypothesized20,25 that LCM should show efficacy for the treatment of focal and generalized tonic– clonic seizures, but not against absence SE.

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Moreover, no patients responded to IV LCM according to our criteria in super-refractory SE. A systemic study to evaluate the treatment for

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refractory and super-refractory SE is difficult because it will always remain uncertain whether the new agent, i.e. LCM, the previously applied firstand second-line drugs, or a spontaneous remission are responsible for the termination of SE. In addition, especially super-refractory SE is an epileptic entity, in which other pathophysiologic factors may complicate therapeutic interventions. Therefore, the etiology and the duration of superrefractory SE before LCM represent exclusively some of the main factors that could explain the lack of IV LCM response in this group of patients. LCM was well tolerated in our series, in spite of high initial doses (patients often received 200-400 mg as the starting dose). The most frequently observed adverse event was a temporary (30 min – 1 h) sedation. However, both the underlying etiology (often, stroke and brain tumors) and concomitant medical diseases (in particular, in elderly patients) could have contributed to the sedation in these patients.

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In conclusion, our study shows that LCM is an easy-to-use, effective, and well-tolerated treatment when used to treat SC in hospitalized patients. As

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add-on therapy, it may be useful to stop seizure activity in patients with focal SE not responding to first/second-line intravenous AEDs. However, a

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large, prospective, double blind study is mandatory to confirm the utility of LCM in the treatment of seizure emergencies.

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REFERENCES

1. Curia G, Biagini G, Perucca E, Avoli M. Lacosamide: A new approach to target voltage-gated sodium currents in epileptic disorders. CNS

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Drugs 2009: 23: 555-568.

2. Goodwin H, Hinson HE, Shermock KM, Karanjia N, Lewin JJ III. The use of lacosamide in refractory status epilepticus. Neurocrit Care

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2011: 14: 348-353.

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3. Kellinghaus C, Berning S, Besselmann M. Intravenous lacosamide as successful treatment for nonconvulsive status epilepticus after failure of first-line therapy. Epilepsy & Behavior 2009; 14: 429-431.

4. Tiz C, Resh R, Hofer T, Eggers C. Successful treatment for refractory convulsive status epilepticus by non-parenteral lacosamide. Epilepsia 2010; 51 (2): 316-317. 5. Kellinghaus C, Berning S, Immish I, et. al. Intravenous lacosamide for treatment of status epilepticus. Acta Neurol Scand 2011: 123: 137141. 6. Koubeissi MZ, Mayor CL, Estephan B, Rashid S, Azar NJ. Efficacy and safety of intravenous lacosamide in refractory nonconvulsive status epilepticus. Acta Neurol Scand 2011: 123: 142-146.

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7. Albers JM, Moddel G, Dittrich R, Steidl C, Suntrup S, Ringelstein EB, Dziewas R. Intravenous lacosamide – An effective add-on treatmente

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of refractory status epilepticus. Seizure 2011: 20: 428-430.

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8. Mnatsakanyan L, Chung JM, Tsimerinov EI, Eliashiv DS. Intravenous lacosamide in refractory nonconvulsive status epilepticus. Seizure 2012; 21: 198-201.

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9. Trinka E. What is the evidence to use new intravenous AEDs in status epilepticus? Epilepsia 2011; 52 (Suppl.8): 35-38. 10. Belcastro V, Vidale S, Pierguidi L, et al. Intravenous lacosamide as treatment option in post-stroke non convulsive status epilepticus in the

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elderly: a proof-of-concept, observational study. Seizure 2013; 22: 905-907. 11. Legros B, Depondt C, Levy-Nogueira M, et al. Intravenous lacosamide in refractory seizure clusters and status epilepticus: comparison of

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200 and 400 mg loading doses. Neurocrit care 2014; 20: 484-488.

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12. Kellinghaus C, Berning S, Stogbauer F. Intravenous lacosamide or phenytoin for treatment of refractory status epilepticus. Acta Neurol Scand 2014: 129: 294-299.

13. Santamarina E, Toledo M, Sueiras M, et al. Usefulness of intravenous lacosamid in status epilepticus. J Neurol 2013; 260: 3122-3128. 14. J. Mirò, Toledo M, Santamarina E, et al. Efficacy of intravenous lacosamide as an add-on treatment in refractory status epilepticus: a multicentric prospective study. Seizure 2013; 22: 77-79. 15. Haut S, Shinnar S, Moshé S. Seizure clustering: risks and outcomes. Epilepsia 2005; 46:146-149. 16. Trinka E, Coch H, Hesdorffer D, et al. A definition and classification of status epilepticus – Report of the ILAE Task Force on classification of status epilepticus. Epilepsia 2015; 56:1515-1523.

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17. Shorvon S. Super-refractory status epilepticus: an approach to therapy in this difficult clinical situation. Epilepsia 2011; 52 Suppl 8: 53-56.

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18. Treiman DM, Meyers PD, Walton NY, et al. A comparison of four treatments for generalized convulsive status epilepticus. N Engl J Med

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1998; 17: 339(12):792-798.

19. Cross SA, Curran MP. Lacosamide in partial-onset seizures. Drugs 2009; 69:449-459.

23:397–8.

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20. d’Orsi G, Pacillo F, Trivisano M, Pascarella MG, Ferrara MA, Specchio LM. Lacosamide in absence status epilepticus. Seizure 2014;

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21. Stohr T, Kupferberg HJ, Stables JP, et al. Lacosamide, a novel anti-convulsant drug, shows efficacy with a wide safety margin in rodents models for epilepsy. Epilepsy Res 2007; 74: 145-154.

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22. Rogawski MA, Tofighy A, White HS, Matagne A, Wolff C. Currente understanding of the mechanism of action of the antiepileptic drug

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lacosamide. Epilepsy Res 2015; 110: 189-205. 23. Donaire A, Carreno M, Gomez B , et al. Cortical laminar necrosis related to prolonged focal status epilepticus. J Neurol Neurosurg Psychiatry 2006;77:104–106.

24. Mantegazza M, Curia G, Biagini G, Ragsdale DS, Avoli M. Voltage-gate sodium channels as therapeutic targets in epilepsy and other neurological disorders. Lancet Neurol 2010;9:413–24. 25. d’Orsi G, Pascarella MG, Martino T., Specchio LM. Lacosamide in absence status epilepticus: effective or ineffective? Seizure 2015; 25:32.

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Legends

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Figure 1: Video-polygraphic monitoring (EEG. EMG: R.Or.Oc.: right orbicularis oculi; R. Mass.: right masseter; R.Orb.Or.: right orbicularis oris; Milo: mylohyoideus muscle; R.SCM: right sternocleidomastoideus. EKG) of refractory focal motor SE in patient 2, after IV diazepam 10 mg

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and IV levetiracetam 3000 mg. A 66 years-old woman was admitted in Clinic of Nervous System Diseases of Foggia because of the presence of repetitive seizures (about every 10 min) characterized by chin and right lower hemifacial clonic jerks, hypersalivation and aphasia with a persistent impairment of consciousness and confusion after seizures. Laboratory tests were normal apart from an elevated serum glucose level of 465 mg/dl

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(normal 50-110), while brain MRI showed a focal area of high signal intensity in the left fronto-central region. Video-polygraphic monitoring demonstrated seizures characterized by rhythmic polyspike activities over the left fronto-centro-temporal region associated with tonic contraction

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predominant in right masseter, right sternocleidomastoideus and myloioideus followed by clonic activity (seizure duration: 35 sec). Before and after electro-clinical seizures, fast epileptiform activity persisted over the left fronto-centro-temporal area with concomitant aphasia and confusion (see

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blue arrows). Although the patient was treated with IV diazepam 10 mg and IV levetiracetam 3000 mg and the hyperglycemia was managed with

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insulin and fluid replacement, and the glucose level was reduced (190 mg/dl), no response in clinical and polygraphic pattern emerged.

Figure 2: Video-polygraphic monitoring of refractory focal motor SE in patient 2, 30 min after first dose of IV LCM 200 mg. Seizure reduced in frequency (to every 30 min), intensity (tonic and clonic muscle contraction are reduced) and duration (13 sec). Rhythmic theta-delta discharge persisted over the left fronto-centro-temporal area, while fast activity was reduced (see blue arrow). Serum glucose level of 180 mg/dl. Figure 3: Video-polygraphic monitoring of refractory focal motor SE in patient 2, 24 h after first dose of LCM (administered 400 mg of LCM). Complete resolution of SE. Theta-delta activity persisted over the left fronto-centro-temporal area (see blue arrow). Serum glucose level of 190 mg/dl.

Table 1. Clinical and EEG features of seizure emergencies.

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SEIZURE CLUSTERS

23 Super-refractory: 8 Refractory: 5 Established: 10

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Gender (F/M)

14/9

7/8

Mean Age (y) (range)

68.5 (33-85)

44.5 (28-65)

History of epilepsy

1/23

6/15

14 4 6 6 6 4 1

5 6 3 3 9 4 0

18 15 3 5 4 1

8 8 0 7 7 0

19 4

15 0

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STATUS EPILEPTICUS

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Number of Patients

Etiology Acute Symptomatic Remote Symptomatic Tumoral Vascular Others Cryptogenic Genetic Clinical Semiology Convulsive Focal Generalized Nonconvulsive Focal Generalized EEG Features Focal Diffuse/Generalized

F: female. M: male. y: years.

Table 2. Seizure emergencies management data

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cr SUPER-REFRACTORY STATUS EPILEPTICUS

8

0/8

REFRACTORY STATUS EPILEPTICUS

5

ESTABLISHED STATUS EPILEPTICUS

10

SEIZURE CLUSTERS

15

us

Immediate Response to LCM

Early Response to LCM

Late Response to LCM

Total Percentage of LCM Response

Side Effects

Outcome (GOS)

0/8

0/8

0%

0/8

7/8 death 1/8 good recovery

3/5

4/5

4/5

80%

0/5

1/5 death 4/5 good recovery

7/10

8/10

8/10

80%

2/10 (dizziness)

10/10 good recovery

12/15

13/15

13/15

86%

0/15

15/15 good recovery

pt

ed

M

an

Number of Patients

LCM: Lacosamide. GOS: Glasgow Outcome Scale.

Ac

ADULTS

ce

Table 3. Published studies with seizure emergencies treated with Lacosamide

Reference

Type

Bachhuber et al, 2016

Retrospective single center observational

Number of patients treated

6

Type of seizure emergencie s Refractory CSE (1 SE, 5 RSE)

M/F

Age

Etiology

Previous AEDs

5/1

Media n 62.5 (range 57-70)

Acute or remote symptomatic

LCM second: 1/6; LCM third 5/6

Sutter et al, 2013

Retrospective single center observational

45

Refractory SE

20/25

Mean 64.7 (SD 15.2)

Parkerson et al, 2011

Retrospective single center

17

ARS (12/17), PLEs (5/17)

10/7

Mean 61

Acute symptomatic (25/45), remote symptomatic (17/45), unknown (3/45) Acute or remote

Duratio n of SE before I.V. LCM N.A.

Success rate

Time to success after I.V. LCM

Dosag e

Adverse events

3/6 (LCM second 0/1; LCM third 3/5)

N.A.

300-400 mg

N.A.

None reported

None reported

LCM mean third drug (range 2-6)

N.A.

21/45

N.A.

100-200 mg bid, without an initial loading dose

LCM second in 9;

N.A.

12/17 (8/12

7-45h

50-200 os bid; 50-

Page 17 of 26

cr us (range (2381)

Case report

1

Super refractory SE

LaRoche et al, 2011

Case report

1

NCSE refractory

1

Case report

NCSE refractory

Female

Female

ce

Retrospective two-center observational

39

Ac

Kellinghaus et al, 2011

Hofler et al, 2011

Kellinghaus et al, 2014

Retrospective two-center observational

Retrospective single-center observational

Total 48; SE 31/48; ARS 17/48

21

SE (GCSE 6/39; complex FSE 17/39; simple FSE 16/39)

CSE 11/48, NCSE 10/48, FSE 10/48, ARS 17/48

Refractory SE

21/18

22/26

8/13

symptomatic

81

Autoimmune

61

SESA

89

Acute symptomatic (basilar artery occlusion)

pt

Krause et al, 2011

Male

M

ShilohMalawsky et al, 2011

ed

an

observational

Median 62 (range 1890)

Acute symptomatic (10/39), remote symptomatic (9/39), prior epilepsy (19/39), other (1/39)

Median 62 (range 1795)

Acute symptomatic (6/48), remote symptomatic (11/48), prior epilepsy (31/48)

Median 70.5 (range 1890)

Acute symptomatic (4/21); remote symptomatic (11/21);

third in 6; forth in 1; fifth in 1 Lorazepam, PHT, LEV, VPA, PB, propofol, midazolam, ketamine LCM fourth: FPHT, LEV, VPA LCM third: Lorazepam, LEV

First or second: 5; third 19; fourth 15

ARS; 4/5 PLEs)

11 weeks

1

5 days

Enteral LCM 25 mg bid

N.A.

N.A.

1

N.A.

N.A.

None reported

N.A.

400 mg iv bolus; second bolus after 6 h

Atrioventricular 3rd degree block with asystolia

7/39 < 6h; 10/39 > 6h

Mean 328 mg (range 200-400)

Allergic skin reaction (1/39), sedation (25/39), hypotension (4/39)

Pruritus (1/48); skin rash (1/48)

None reported

> 24 h

0/1

N.A.

17/39 (first or second 3/5; third 11/19; fourth 3/15)

N.A.

SE 25/31. first: 2/2; second 6/6; third 11/15; fourth 6/8 ARS 17/17. first 8/8; second 3/3; third 6/6

N.A.

Median 200 (range 100-400)

7/21

Median 9.5h. 1-24h 5/21; > 24h 7/21

Median 400 (200800)

SE: first 2/31; second 6/31; third 5/31; fourth 8/31 ARS: first 8/17; second 3/17; third: 6/17

BZD, LEV; LCM as third

200 iv bid

Median 19h

Page 18 of 26

cr us Prospective observational

CSE refractory

1

Male

23 CSE; 30 NCSE

53

37/16

38

Median 55.2 (range 3872)

Retrospective multicenter observational

Total 98; SE 55; ARS 43

NCSE 43; CSE 12; ARS 43

42/56

Mean 59.8 (range 1891)

Ac

Garces et al, 2014

ce

pt

ed

Morales et al, 2015

Case report

M

Tilz et al, 2010

an

unknown or others (6/21)

Rantsch et al, 2011

Retrospective single-center observational

Belcastro et al, 2013

Retrospective single-center observational

Mnatsakany aet al, 2012

Retrospective single center observational

10

Chen et al,

Case report

1

10

16

Refractory NCSE 8; EPC 2 NCSE (7 simple NCSE; 9 complex NCSE) Refractory NCSE (focal 8/10; generalized 2/10) Refractory

Infantile cerebral palsy

Diazepam, ETO, midazolam, lorazepam, LEV; LCM sixth

N.A.

11/53 first line; second 18/53; third 12/53; fourth 12/53

Acute symptomatic 29/98; remote symptomatic 18/98; prior epilepsy 48/98; unknown 3/98

SE first 1; second 22; third 19; fourth 8, fifth 1; sixth 4

ARS first 6; second 19; third 12; fourth 2; fifth 4

< 2h

N.A.

SE median 22 (range 0.9-552); ARS median 24 (range 1365)

1

48/53; CSE 21/23; NCSE 27/30 SE first 0/1; second 17/22; third 11/19; fourth 6/8; fifth 1/1; sixth 4/4 ARS first 5/6; second 14/19; third 11/12; fourth 2/2; fifth 4/4

30 min

150mg via percutane ous gastric fistula

None reported

N.A.

400mg

None reported

>24h

Median 200 (50400)

Somnolence (8/98); nausea (4/98); dizziness (3/98); diplopia (1/98); blurred vision (1/98); vomiting (1/98); PR interval prolongation (1/98); AV block (1/98)

3/6

Mean 67.1 (SD 12.4)

Acute symptomatic

LCM median 6.5 drug (range 4-12)

Median 166 h (range 8637)

2/10

N.A.

50-100 mg

None reported

7/9

Mean 77 (SD 7)

Post-stroke

LCM as first drug

N.A.

8/16

45-60 min

400 mg

None reported

4/6

Median 60.5 (range 1690)

9/10 acute or remote symptomatic; 1/10 unknown

LCM third line or more

24-48 h

7/10

1/10 immediate termination of SE

200-300 mg

None reported

M

57

Prior epilepsy

LCM forth

4 days

1/1

< 24h

oral LCM

N.A.

Page 19 of 26

cr us

M

Prospective multicenter observational

34

18/16

Kellinghaus et al, 2009

Legros et al, 2014

pt 31

ce

Ac

Santamarina et al, 2013

Retrospective single-center observational

Case report

Prospective single-center observational

1

25

CSE 4/31; NCSE 10/31; EPC 17/31

NCSE

RSE 21/25; SC 4/25

17/14

F

13/12

after LZP, FPHT, LEV

Mean 60.15 (range 2286)

Acute symptomatic 11/34; remote symptomatic 9/34; forgotten or suppression AEDs 5/34; cryptogenic 2/34; tumoral 1/34; others 6/34

LCM as third or fourth drug in 18/34; LCM as fifth or more in 16/34

Mean 61.8 (range 2185)

Acute symptomatic 15/31; remote symptomatic 11/31; cryptogenic 5/31

42

Remote symptomatic (cardioemboli c stroke of the MCA)

ed

Mirò et al, 2013

Refractory: Simple FMSE 7/34; complex FMSE 21/34; NCSE 5/34; GCSE 1/34

due to a traumatic left brain injury

an

simple motor SE

2011

Median 56 (range 1784)

Acute symptomatic 15/25; remote symptomatic 6/25; unknown 4/25

50mg x 2

9/22 in < 60min; 8/22 in < 12h; 5/22 in 1248h

100-400

Diplopia (1/34); confused state and nystagmus (1/34)

Dizziness (2/31); PR interval prolongation (2/31)

Median 48h (range 1250)

22/34

LCM as second or third drug in 13/31; LCM as fourth or fifth in 18/31

Median 30h (range 3200)

21/31 (LCM as second or third 11/13; LCM as fourth or fifth 10/18)

Median 20h (range 1-96)

Median 400 (range 200-600)

LCM as third (after diazepam and lorazepam)

Approx 2 h

1/1

5 mins

200 mg iv

Mild allergic skin reaction

200-400 mg iv bolus

Myoclonus and confusion (1/25, in a patient with chronic renal failure); seizure increase in frequency and severity (1/25); vertigo (1/25); ataxia (1/25); asymptomatic

LCM as third line agent (range first-fifth)

Median 2 days (range 1-7)

Page 20 of 26

9/25 (2/11 of 200mg bolus; 7/14 of 400mg bolus)

<3h in 4/25; 3-24h in 8/25; >24h in 1/25

cr us Albers et al, 2011 Koubeissi et al, 2011

2/7

Case series

7

7 SRSE

6/1

Case series

4

Grosso et al, 2014

Jain et al, 2012

Refractory NCSE

0/4

Median 63 (range 4789)

Acute and remote symptomatic

Median 63 (range 3383) Median 65 (range 5379)

Acute symptomatic 7/7 Acute vascular

LCM as third line agent (range 2-5) LCM as third line or more LCM as third line or more

Median 2 days (range 2-14)

N.A.

0/9

Median 200 mg

Acute angioedema (2/9)

1-21 days

1/7 < 1 h; 6/7 < 24h

7/7

400 mg

None reported

Range 350h

Range 15 min – 2h

4/4

50100mg

None reported

Duratio n of SE before I.V. LCM

Success rate

Time to success after I.V. LCM

Dosag e

Adverse events

LCM third after benzo; PHT or LEV; other

N.A.

23/32: 0/3 EPC; 0/4 SRSE; 5/5 RSE; 2/2 SE; 16/18 ASE

N.A.

Range 111 mg/kg

Sedation (5/32); ataxia (1/32)

LZP, MDZ, PHT, VPA, PB, LCM fifth line or greater

Median 58 h (range 22576 h)

5/11: CSE 3/6; NCSE 2/5

< 12h: 3; 12-26h: 2

Mean 8.6 mg/kg (range 6.7-9.9)

None reported

< 30 min

50mg, 100mg, 100mg bid

Chorea (1/3, day 5); oculogyric crisis /1/3, day 4)

pt Numbe r of patient s treated

ce

Type

Ac

Arkilo et al, 2016

ed

9

5 RSE; 4 SRSE

CHILDREN

Reference

an

Retrospective single-center observational

M

Goodwin et al, 2011

increase of liver enzymes (1/25, in a person with sepsis and chronic alcohol abuse)

Retrospective single-center observational

Retrospective multicenter observational

Case series

32

11

3

Type of seizure emergencie s

EPC 3; SE 2; SRSE 4; RSE 5; ASE 18

11 refractory SE (6 CSE, 5 NCSE)

3 Refractory tonic SE

M/F

14/18

Age

Range 1 month – 12 years

5/6

Mean 9.4 (range 316)

1/2

Median 16 (range 1217)

Etiology

Various

3/11 unknown; 9/11 prior epilepsy; 2/11 acute symptomatic LennoxGastaus syndrome; Rett syndrome; myoclonic

Previous AEDs

LCM as fourth line or more

Range 828h

Page 21 of 26

3/3

cr us Ac

ce

pt

ed

M

an

atonic epilepsy

Page 22 of 26

d

M

an

us

cr

Abbreviations: SESA: subacute encephalopathy with seizures in alcoholics SE: status epilepticus CSE: convulsive status epilepticus NCSE: non-convulsive status epilepticus FSE: focal status epilepticus PLEs: periodic epileptiform patterns FMSE: focal motor status epilepticus GCSE: generalized convulsive status epilepticus ETO: etomidate N.A.: data not available EPC: epilepsia partialis continua RSE: refractory status epilepticus SRSE: super-refractory status epilepticus ASE: acute seizure exacerbation LZP: lorazepam MDZ: midazolam VPA: valproic acid PHT: phenytoin PB: phenobarbital FPHT: fosphenytoin MCA: middle cerebral artery AEDs: anti-epileptic drugs IV: intravenous

ip t

G. d’Orsi et al. 23

Ac ce pt e

Bibliography: Bachhuber, A., Lasrich, M., Halmer, R., Fassbender, K., & Walter, S. (2016). Comparison of Antiepileptic Approaches in Treatment of Benzodiazepine Nonresponsive Status Epilepticus. CNS neuroscience & therapeutics, 22(3), 178-183. Sutter, R., Marsch, S., & Rüegg, S. (2013). Safety and efficacy of intravenous lacosamide for adjunctive treatment of refractory status epilepticus: a comparative cohort study. CNS drugs, 27(4), 321-329. Shiloh-Malawsky, Y., Fan, Z., Greenwood, R., & Tennison, M. (2011). Successful treatment of childhood prolonged refractory status epilepticus with lacosamide. Seizure, 20(7), 586-588. LaRoche, S. M., & Shivdat-Nanhoe, R. (2011). Subacute encephalopathy and seizures in alcoholics (SESA) presenting with non-convulsive status epilepticus. Seizure, 20(6), 505-508. Parkerson, K. A., Reinsberger, C., Chou, S. H., Dworetzky, B. A., & Lee, J. W. (2011). Lacosamide in the treatment of acute recurrent seizures and periodic epileptiform patterns in critically ill patients. Epilepsy & Behavior, 20(1), 48-51. Krause, L. U., Brodowski, K. O., & Kellinghaus, C. (2011). Atrioventricular block following lacosamide intoxication. Epilepsy & Behavior, 20(4), 725727.

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G. d’Orsi et al. 24

Ac ce pt e

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Kellinghaus, C., Berning, S., Immisch, I., Larch, J., Rosenow, F., Rossetti, A. O., ... & Trinka, E. (2011). Intravenous lacosamide for treatment of status epilepticus. Acta neurologica Scandinavica, 123(2), 137-141. Höfler, J., Unterberger, I., Dobesberger, J., Kuchukhidze, G., Walser, G., & Trinka, E. (2011). Intravenous lacosamide in status epilepticus and seizure clusters. Epilepsia, 52(10), e148-e152. Kellinghaus, C., Berning, S., & Stögbauer, F. (2014). Intravenous lacosamide or phenytoin for treatment of refractory status epilepticus. Acta Neurologica Scandinavica, 129(5), 294-299. Tilz, C., Resch, R., Hofer, T., & Eggers, C. (2010). Successful treatment for refractory convulsive status epilepticus by non parenteral lacosamide. Epilepsia, 51(2), 316-317. Morales, E. Y. M., Peleteiro, M. F., Peña, E. C. B., Lorenzo, J. M. D., Santiago, E. P., & Fernández, A. (2015). Observational Study of Intravenous Lacosamide in Patients with Convulsive Versus NonConvulsive Status Epilepticus. Clinical drug investigation, 35(7), 463-469. Garcés, M., Villanueva, V., Mauri, J. A., Suller, A., García, C., González, F. J. L., ... & Santafé, C. (2014). Factors influencing response to intravenous lacosamide in emergency situations: LACO-IV study. Epilepsy & Behavior, 36, 144-152. Arkilo, D., Gustafson, M., & Ritter, F. J. (2016). Clinical experience of intravenous lacosamide in infants and young children. European Journal of Paediatric Neurology, 20, 212-216 Belcastro, V., Vidale, S., Pierguidi, L., Sironi, L., Tancredi, L., Striano, P., ... & Arnaboldi, M. (2013). Intravenous lacosamide as treatment option in post-stroke non convulsive status epilepticus in the elderly: A proof-ofconcept, observational study. Seizure, 22(10), 905-907. Grosso, S., Zamponi, N., Bartocci, A., Cesaroni, E., Cappanera, S., Di Bartolo, R., & Balestri, P. (2014). Lacosamide in children with refractory status epilepticus. A multicenter Italian experience. european journal of paediatric neurology, 18(5), 604-608. Rantsch, K., Walter, U., Wittstock, M., Benecke, R., & Rösche, J. (2011). Efficacy of intravenous lacosamide in refractory nonconvulsive status epilepticus and simple partial status epilepticus. Seizure, 20(7), 529-532. Mnatsakanyan, L., Chung, J. M., Tsimerinov, E. I., & Eliashiv, D. S. (2012). Intravenous lacosamide in refractory nonconvulsive status epilepticus. Seizure, 21(3), 198-201. Chen, L. L., Haneef, Z., Dorsch, A., Keselman, I., & Stern, J. M. (2011). Successful treatment of refractory simple motor status epilepticus with lacosamide and levetiracetam. Seizure, 20(3), 263-265. Miró, J., Toledo, M., Santamarina, E., Ricciardi, A. C., Villanueva, V., Pato, A., ... & Falip, M. (2013). Efficacy of intravenous lacosamide as an add-on treatment in refractory status epilepticus: a multicentric prospective study. Seizure, 22(1), 77-79. Santamarina, E., Toledo, M., Sueiras, M., Raspall, M., Ailouti, N., Lainez, E., ... & Puig, X. S. (2013). Usefulness of intravenous lacosamide in status epilepticus. Journal of neurology, 260(12), 3122-3128. Kellinghaus, C., Berning, S., & Besselmann, M. (2009). Intravenous lacosamide as successful treatment for nonconvulsive status epilepticus after failure of first-line therapy. Epilepsy & Behavior, 14(2), 429-431.

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Legros, B., Depondt, C., Levy-Nogueira, M., Ligot, N., Mavroudakis, N., Naeije, G., & Gaspard, N. (2014). Intravenous lacosamide in refractory seizure clusters and status epilepticus: comparison of 200 and 400 mg loading doses. Neurocritical care, 20(3), 484-488. Goodwin, H., Hinson, H. E., Shermock, K. M., Karanjia, N., & Lewin III, J. J. (2011). The use of lacosamide in refractory status epilepticus. Neurocritical care, 14(3), 348-353. Albers, J. M., Möddel, G., Dittrich, R., Steidl, C., Suntrup, S., Ringelstein, E. B., & Dziewas, R. (2011). Intravenous lacosamide—an effective add-on treatment of refractory status epilepticus. Seizure, 20(5), 428-430. Jain, V., & Harvey, A. S. (2012). Treatment of refractory tonic status epilepticus with intravenous lacosamide. Epilepsia, 53(4), 761-762. Koubeissi, M. Z., Mayor, C. L., Estephan, B., Rashid, S., & Azar, N. J. (2011). Efficacy and safety of intravenous lacosamide in refractory nonconvulsive status epilepticus. Acta neurologica Scandinavica, 123(2), 142-146.

an

Highlights

• IV LCM is effective in seizure clusters in a hospital adult setting. • IV LCM is effective in established focal status epilepticus.

Ac ce pt e

Figure 1

d

effects.

M

• The loading of IV LCM was well tolerated, with mild adverse

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G. d’Orsi et al. 26

M

Ac ce pt e

d

Figure 3

an

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Figure 2

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