Levetiracetam Intravenous Infusion as an Alternative to Oral Dosing in Patients with Partial-Onset Seizures

Intravenous perampanel as an alternative to the oral formulations in Japanese patients with epilepsy

OBJECTIVE

Perampanel is an oral anti-seizure medication, which is approved in Japan for focal-onset seizures, with/without focal to bilateral tonic-clonic seizures, as monotherapy/adjunctive therapy in patients aged 4 years and older. Treatment for generalized tonic-clonic seizures as adjunctive therapy in patients aged 12 years and older is approved as well. We evaluated the feasibility of intravenous (IV) administration of perampanel as an alternative to oral administration.

METHODS

Study 240 (NCT03754582) was an uncontrolled, open-label study of IV perampanel, conducted in 21 Japanese patients with epilepsy who received a stable dose of 8-12 mg/day of oral perampanel. Patients received 30-minute IV infusions at equivalent daily doses of oral perampanel for 4 days, then were switched back to oral perampanel. Safety, tolerability, plasma concentration, and maintenance of efficacy throughout the transition between IV and oral dosing of perampanel were assessed. As supportive data, a subgroup analysis was also conducted using data from healthy Japanese subjects (n = 18) who were enrolled in Study 050 (NCT03376997) investigating the pharmacokinetics and safety of IV perampanel in healthy subjects who received an IV infusion (30-, 60-, or 90-minute) of perampanel 12 mg and a single oral administration of perampanel 12-mg tablet.

RESULTS

In Study 240, the transition between 30-minute IV and oral perampanel dosing was associated with a ≤1.4-fold increase in the mean change in maximum observed concentration of perampanel. Seizure outcomes demonstrated no considerable changes in efficacy before, during, or after 30-minute IV dosing of perampanel. The safety profiles were similar between IV and oral formulations. In Study 050, the pharmacokinetics of 30- or 60-minute IV infusion of perampanel further support the interchangeability between oral and IV formulations in the Japanese subjects.

SIGNIFICANCE

These results support that 30-minute IV perampanel may be a potential short-term alternative to oral formulations for patients with epilepsy.

Effects of levetiracetam treatment on autonomic nervous system functions in pediatric epilepsy patients

BACKGROUND

This study investigated the effects of levetiracetam (LEV) treatment on cardiac rhythm and heart rate variability.

METHODS

The study included two groups of patients diagnosed with non-lesional epilepsy who had not yet been treated and who presented to the outpatient pediatric neurology clinic at Van Training and Research Hospital, Van, Turkey, between 2019 and 2020. The heart rate variability (HRV) of 47 patients in the first group, before and at the 3rd month of treatment, and intravenous (IV) LEV loading in 13 patients in the second group was evaluated by Holter electrocardiography (ECG).

RESULTS

It was determined that the values of triangular index, standard deviation of the RR intervals over a 24-hour period (SDNN), standard deviation of all 5-minute mean RR intervals (SDANN), mean of standard deviations of all normal RR intervals (SDNNI), the percentage of RR intervals with >50-millisecond variation (PNN50), and the square root of mean squared differences of successive RR intervals (RMSSD). HRV of 47 patients under LEV treatment significantly increased in the 3rd month of treatment compared to baseline (p < 0.05). No difference was found in HRV between the intravenous loading and the control group (p > 0.05).

CONCLUSIONS

Our study suggests that the sympathovagal balance before treatment in the patient group is in favor of the sympathetic nervous system and that the sympathovagal imbalance improves after treatment. Our results show that LEV monotherapy and loading have no negative effect on HRV and potential cardiac arrhythmia risk in children with epilepsy.

The safety of rapid infusion levetiracetam: A systematic review

Epilepsy is a common diagnosis and can quickly progress to status epilepticus which requires rapid treatment. Levetiracetam is a frequent treatment choice in these situations. The approved administration of intravenous levetiracetam is an infusion over 15 min. In recent years, studies have been published on faster infusion rates of levetiracetam. The objective of this review is to discuss the safety of levetiracetam as an intravenous push at a rate quicker than recommended. A literature search using PubMed, Cochrane Library, ClinicalTrials.gov, and Google Scholar resulted in 192 articles. Inclusion criteria consisted of English language, human studies, use of levetiracetam administered intravenously at a rate faster than 15 min, discussion of safety, and full-text availability. After screening, nine articles remained for inclusion. Of the nine articles, one was a prospective, open-label study, six were retrospective studies, and two were open-label, randomized controlled trials. The most common rapid infusion speed was 5 min and doses ranged from 280 to 4500 mg. Some of these trials used undiluted levetiracetam and many reported that peripheral access was used for a portion or all of the administrations. There were few adverse effects, including specific adverse effects relating to medication concentration and speed of infusion, in all the studies. Administration of intravenous levetiracetam at a rate faster than recommended in the labeling information appears to be safe and tolerable and can be given via a peripheral line. Rapid infusion of levetiracetam is a beneficial method of administration in an acute care setting where patients need rapid attainment of therapeutic levels of antiepileptic medications. Additional research is needed to ensure that rapid administration of intravenous levetiracetam is as efficacious as the traditional dosing method.

Intravenous Perampanel as an Interchangeable Alternative to Oral Perampanel: A Randomized, Crossover, Phase I Pharmacokinetic and Safety Study

Intravenous (IV) drug administration enables treatment of epilepsy when oral administration is temporarily not feasible. Perampanel is a once‐daily antiseizure medication currently available as oral formulations. Study 050 (NCT03376997) was an open‐label, randomized, single‐dose, crossover study to evaluate the interchangeability of oral and IV perampanel in healthy subjects (N = 48). Bioequivalence of single 12‐mg doses of IV (30‐, 60‐, or 90‐minute infusion) and oral perampanel, ≥6 weeks apart, was assessed. Analyses indicated bioequivalence of area under the plasma concentration–time curve extrapolated to infinity for 30‐ and 60‐minute IV infusions and oral perampanel doses (geometric mean ratio [90% confidence interval], 0.93 [0.84–1.02] and 1.03 [0.97–1.09], respectively); however, IV maximum observed drug concentration (C_max) values were 1.35‐ to 1.61‐fold higher than C_max. Simulated plasma concentration–time profiles using pooled pharmacokinetic data further supported oral and IV perampanel interchangeability in two scenarios: 12‐mg per day IV dosing during a temporary 7‐day switch from oral steady‐state maintenance therapy, and treatment initiation with 2‐mg perampanel. Thirty‐four (70.8%) subjects experienced treatment‐related adverse events. The IV perampanel safety profile was similar to that of oral perampanel without new safety concerns. Perampanel IV infusions may be a suitable temporary alternative to oral perampanel for treatment maintenance and/or initiation.

Efficacy, Safety, and Economics of Intravenous Levetiracetam for Status Epilepticus: A Systematic Review and Meta-Analysis

Objective

To evaluate efficacy, safety, and economics profiles of intravenous levetiracetam (LEV) for status epilepticus (SE).

Methods

We searched PubMed, Embase, the Cochrane Library, Clinicaltrials.gov, and OpenGrey.eu for eligible studies published from inception to June 12^th 2019. Meta-analyses were conducted using random-effect model to calculate odds ratio (OR) of included randomized controlled trials (RCTs) with RevMan 5.3 software.

Results

A total of 478 studies were obtained. Five systematic reviews (SRs)/meta-analyses, 9 RCTs, 1 non-randomized trial, and 27 case series/reports and 1 economic study met the inclusion criteria. Five SRs indicated no statistically significant difference in rates of seizure cessation when LEV was compared with lorazepam (LOR), phenytoin (PHT), or valproate (VPA). Pooled results of included RCTs indicated no statistically significant difference in seizure cessation when LEV was compared with LOR [OR = 1.04, 95% confidence interval (CI) 0.37 to 2.92], PHT (OR = 0.90, 95% CI 0.64 to 1.27), and VPA (OR = 1.47, 95% CI 0.81 to 2.67); and no statistically significant difference in seizure freedom within 24 h compared with LOR [OR = 1.83, 95% CI 0.57 to 5.90] and PHT (OR = 1.08, 95% CI 0.63 to 1.87). Meanwhile, LEV did not increase the risk of mortality during hospitalization compared with LOR (OR = 1.03, 95% CI 0.31 to 3.39), PHT (OR = 0.89, 95% CI 0.37 to 2.10), VPA (OR = 1.28, 95% CI 0.32 to 5.07), and placebo (plus clonazepam, OR = 0.73, 95% CI 0.16 to 3.38). LEV had lower need for artificial ventilation (OR = 0.23, 95% CI 0.06 to 0.92) and a lower risk of hypotension (OR = 0.15, 95% CI 0.03 to 0.84) compared to LOR. A trend of lower risk of hypotension and higher risk of agitation was found when LEV was compared with PHT. Case series and case report studies indicated psychiatric and behavioral adverse events of LEV. Cost-effectiveness evaluations indicated LEV as the most cost-effective non-benzodiazepines anti-epileptic drug (AED).

Conclusions

LEV has a similar efficacy as LOR, PHT, and VPA for SE, but a lower need for ventilator assistance and risk of hypotension, thus can be used as a second-line treatment for SE. However, more well-conducted studies to confirm the role of intravenous LEV for SE are still needed.

Pharmacokinetic and Pharmacodynamic Evaluation of Intravenous Levetiracetam in Children With Epilepsy

This study aimed to evaluate the safety and tolerability of intravenous (IV) levetiracetam (LEV) as a monotherapy in children aged 1 month-16 years and to explore the pharmacokinetics (PK) of IV LEV and the time to seizure after IV then oral administration of LEV in pediatric children with epilepsy. Children diagnosed with acute unprovoked seizures requiring in-hospital IV LEV administration were included. After administration, the clinical seizure outcomes, side effects, and the Korean-Child Behavior Checklist were monitored and the PK and repeated time to seizure were analyzed via modeling using NONMEM software. Overall, 37 children with epilepsy were enrolled and underwent a PK analysis (median age, 4.6 years; median weight, 18.0 kg). Nine children (24.3%) had seizure recurrence during the follow-up period (median, 3.8 months) and 5 children (13.5%) experienced LEV-associated adverse events such as irritability (n = 2; 5.4%) and somnolence (n = 3; 8.1%). The plasma LEV concentrations after IV LEV were best described by a one-compartment linear PK model. Only body weight was associated with both the clearance and volume of distribution of LEV. The Weibull distribution model described the time to seizure recurrence well; no statistically significant predictor for the time to seizure was identified. Therefore, IV LEV was a well-tolerated and effective alternative in children with acute unprovoked seizures, and models for the PK and time to repeated seizure recurrence after LEV were successfully developed. In particular, the current use of a weight-based IV LEV dosing regimen in pediatric children is practical.

A multicentre randomised controlled trial of levetiracetam versus phenytoin for convulsive status epilepticus in children (protocol): Convulsive Status Epilepticus Paediatric Trial (ConSEPT) - a PREDICT study

Background

Convulsive status epilepticus (CSE) is the most common life-threatening childhood neurological emergency. Despite this, there is a lack of high quality evidence supporting medication use after first line benzodiazepines, with current treatment protocols based solely on non-experimental evidence and expert opinion. The current standard of care, phenytoin, is only 60% effective, and associated with considerable adverse effects. A newer anti-convulsant, levetiracetam, can be given faster, is potentially more efficacious, with a more tolerable side effect profile. The primary aim of the study presented in this protocol is to determine whether intravenous (IV) levetiracetam or IV phenytoin is the better second line treatment for the emergency management of CSE in children.

Methods/Design

200 children aged between 3 months and 16 years presenting to 13 emergency departments in Australia and New Zealand with CSE, that has failed to stop with first line benzodiazepines, will be enrolled into this multicentre open randomised controlled trial. Participants will be randomised to 40 mg/kg IV levetiracetam infusion over 5 min or 20 mg/kg IV phenytoin infusion over 20 min. The primary outcome for the study is clinical cessation of seizure activity five minutes following the completion of the infusion of the study medication. Blinded confirmation of the primary outcome will occur with the primary outcome assessment being video recorded and assessed by a primary outcome assessment team blinded to treatment allocation. Secondary outcomes include: Clinical cessation of seizure activity at two hours; Time to clinical seizure cessation; Need for rapid sequence induction; Intensive care unit (ICU) admission; Serious adverse events; Length of Hospital/ICU stay; Health care costs; Seizure status/death at one-month post discharge.

Discussion

This paper presents the background, rationale, and design for a randomised controlled trial comparing levetiracetam to phenytoin in children presenting with CSE in whom benzodiazepines have failed. This study will provide the first high quality evidence for management of paediatric CSE post first-line benzodiazepines.

Trial registration

Prospectively registered with the Australian and New Zealand Clinical Trial Registry (ANZCTR): ACTRN12615000129583 (11/2/2015). UTN U1111–1144-5272. ConSEPT protocol version 4 (12/12/2014).

Intravenous levetiracetam in clinical practice--Results from an independent registry

PURPOSE

Most common clinical studies with antiepileptic drugs do not reflect medical everyday practice due to their strict in- and exclusion criteria and specifications of treatment regimens. Here we present a large non-interventional registry with the intention to evaluate the spectrum of applications in daily use and the efficacy and tolerability of intravenously given levetiracetam (LEV-iv).

METHODS

In a prospective approach of 17 neurological and neuropediatric centres in Germany LEV-iv treated patients of all ages were included over a period of 10 months. The observational period was 10 days with daily documentation of LEV-iv administration, type and frequency of seizures, currently used drugs and doses, and adverse events (AEs). In addition, treatment efficacy and tolerability were assessed by patients and physicians at study end as well as practicability of LEV-iv using a five-step scale.

RESULTS

In 95 patients LEV-iv was administered, 93 were included into the analysis. The median LEV-iv dose was 1500 mg (range 110-6000 mg) per day. Median age was 66 years (range 0.7-90.3 years). The majority of patients (n=70, 75%) suffered from status epilepticus (SE, n=55, 59%) and acute seizure clusters (n=15, 16%). Of those with SE, 41 patients (75%) had SE for the first time. Acute seizure clusters and SE terminated in 83% after LEV-iv administration. A total of 29 adverse events were reported in 17 of the 95 patients from the safety set. Ten of these were at least possibly related to LEV-iv treatment. Slight decrease of blood pressure during the infusion (3 patients each) was captured most frequently. No serious side effect was observed. Physicians rated the efficacy and tolerability of LEV-iv treatment as good or very good in 78% and 82% of the cases, respectively.

CONCLUSION

In this large observational study of everyday practise the use of LEV-iv exhibited a remarkable good response and tolerability in patients with acute onset seizures (mostly SE). Further randomized controlled studies, like the established status epilepticus trial (ESET) are needed to confirm these findings.

Pharmacokinetics of the antiepileptic drug levetiracetam in healthy Japanese and Caucasian volunteers following intravenous administration

The intravenous (iv) formulation of levetiracetam has been available in clinical practice worldwide for several years, but not in Japan. Two open-label studies were conducted: Study A evaluated the bioequivalence of iv and oral tablet formulations in healthy Japanese volunteers; and Study B subsequently compared the pharmacokinetics of iv levetiracetam in healthy Japanese and Caucasian volunteers. Study A had a randomised, two-way crossover design; a single 1,500 mg levetiracetam dose was administered as a 15-min iv infusion and as 3 × 500 mg oral tablets to Japanese volunteers. In Study B, 1,500 mg levetiracetam was administered as single and repeated 15-min iv infusions to Japanese and Caucasian volunteers. Overall, 26/27 volunteers completed Study A and 32/32 (16 Japanese; 16 Caucasian) completed Study B. In Study A, the point estimate and 90 % confidence interval (CI) for the geometric least squares mean (LSM) ratio (iv vs oral) were fully included within the acceptance range for bioequivalence (0.85-1.25) for the area under plasma concentration-time curve from 0 to last quantifiable observation (AUClast 0.97 [0.95, 0.99]), but not for the maximum plasma concentration (C max 1.64 [1.47, 1.83]). In Study B, after a single iv infusion, the point estimates (90 % CI) for the geometric LSM ratio (Japanese vs Caucasian) for body weight-normalised C max and AUClast were 1.21 (1.07, 1.36) and 0.97 (0.90, 1.04), respectively. Corresponding values after repeated iv infusions were C max,ss 1.01 (0.91, 1.12) and AUCτ,ss 0.89 (0.83, 0.96). Levetiracetam was well tolerated in both studies. Study A did not demonstrate the bioequivalence of single doses of levetiracetam 1,500 mg administered as an iv infusion and as oral tablets in healthy Japanese adults. Study B, however, showed that pharmacokinetic profiles were generally similar between Japanese and Caucasian adults after single and repeated iv infusions of levetiracetam 1,500 mg.

Measurement of levetiracetam drug levels to assist with seizure control and monitoring of drug interactions with other anti-epileptic medications (AEMs)

PURPOSE

Levetiracetam (LEV) therapeutic range (20-40mg/L) and potential drug interactions were assessed in people with epilepsy (PWE).

METHOD

Fifty-two PWE had LEV and concomitant medications [carbamazepine (CBZ); valproate (VPA); lamotrigine (LTG)] blood levels measured and compared to seizure activity. Lacosamide (LCM) levels were unavailable. Adopted therapeutic ranges were: 20-40mg/L - LEV; 25-50μmol/L - total CBZ; 6-13μmol/L - free CBZ; 300-750μmol/L - total VPA; 30-75μmol/L - free VPA; and 40-60μmol/L - LTG. Seizure-freedom was assessed and patients followed for almost two years.

RESULTS

23 of 52 PWE (44%) used LEV monotherapy and 16/23 (70%) had 'therapeutic' LEV with 13/16 (81%) seizure-free. 29 of 52 (56%) used polytherapy and 16/29 (55%) had 'therapeutic' LEV with 7/16 (44%) seizure-free. 11 of 29 (38%) used CBZ: 4/11 (36%) had therapeutic mean LEV levels and 7/11 (64%) were seizure-free. Fourteen (48%) used VPA: 9/14 (64%) had therapeutic mean LEV levels and 8/14 (57%) were seizure-free. 13 of 29 (45%) used LTG: 8/13 (62%) had therapeutic mean LEV levels and 5/13 (38%) were seizure-free. LEV did not alter CBZ, but CBZ affected LEV. LEV elevated VPA free levels but not VPA total levels. Dosage/concentration was lowered with polytherapy.

CONCLUSION

LEV range (20-40mg/L) assisted epilepsy management and anti-epileptic medication interactions were suggested with polytherapy thus possibly explaining the impaired efficacy of LEV with polytherapy.

The safety and tolerability of different intravenous administrations of levetiracetam, bolus versus infusion, in intensive care unit patients

This study reviews our experience with the safety and tolerability of levetiracetam (LVM) with different methods of intravenous administration in intensive care unit (ICU) patients. We used retrospective chart review to identify 33 ICU patients who received intravenous LVM for treatment of seizures. Collected data included age, gender, diagnosis on admission, dosing regimen, documented seizure activity, adverse reactions, concomitant use of other antiepileptic drugs, and condition on discharge. A total of 33 ICU patients were given intravenous (IV) LVM as add-on treatment to standard regimen for treatment of breakthrough seizures or status epilepticus or given as preventive medication postoperatively. Among these 33 patients, 16 received intravenous LVM as bolus, and 17 received intravenous LVM as continuous infusion. Safety and tolerability of intravenous LVM were evaluated on the basis of the occurrence of adverse or side effects reported in daily progress notes of the physicians and nurses. There were no significant adverse or side effects reported in daily progress notes. The addition of intravenous LVM to the standard regimen for controlling seizures in ICU patients seems feasible and tolerable.

Prospective Open-Label, Single-Arm, Multicenter, Safety, Tolerability, and Pharmacokinetic Studies of Intravenous Levetiracetam in Children With Epilepsy

Levetiracetam given via intravenous administration has been shown to be an effective alternative in adults with epilepsy when oral administration is not feasible. This study was a prospective single-arm, multicenter study to assess tolerability, safety, and pharmacokinetics of intravenous levetiracetam in children with epilepsy. Children with epilepsy ages 1 month to 16 years requiring intravenous levetiracetam were enrolled. Assessments included vital signs, electrocardiogram, hematology, chemistry, plasma concentrations of antiepileptic medications, weight, physical/neurological examinations, and pharmacokinetics. A total of 52 patients were enrolled. Mild to moderate treatment-emergent adverse events occurred in 63%, the most frequent being pyrexia and dry mouth. Most other treatment-emergent adverse events were considered unrelated to intravenous levetiracetam administration. Therefore, intravenous levetiracetam in the acute setting was overall well tolerated in children 1 month to 16 years.

The role of levetiracetam in treatment of seizures in brain tumor patients

Levetiracetam, trade name Keppra, is a new second generation antiepileptic drug that is being increasingly used in brain tumor patients. In patients suffering with brain tumors, seizures are one of the leading neurologic complications being seen in more than 30% of patients. Unlike other antiepileptic drugs, levetiracetam is proposed to bind to a synaptic vesicle protein inhibiting calcium release. Brain tumor patients are frequently on chemotherapy or other drugs that induce cytochrome P450, causing significant drug interactions. However, levetiracetam does not induce the P450 system and does not exhibit any relevant drug interactions. Intravenous delivery is as bioavailable as the oral medication allowing it to be used in emergency situations. Levetiracetam is an attractive option for brain tumor patients suffering from seizures, but also can be used prophylactically in patients with brain tumors, or patients undergoing neurological surgery. Emerging studies have also demonstrated that levetiracetam can increase the sensitivity of Glioblastoma tumors to the chemotherapy drug temozolomide. Levetiracetam is a safe alternative to conventional antiepileptic drugs and an emerging tool for brain tumor patients combating seizures.

Efficacy and tolerability of intravenous levetiracetam in childrens

Intractable epilepsy in children poses a serious medical challenge. Acute repetitive seizures and status epilepticus leads to frequent emergency room visits and hospital admissions. Delay of treatment may lead to resistance to the first-line anticonvulsant therapies. It has been shown that these children continue to remain intractable even after acute seizure management with approved Food and Drug Administration (FDA) agents. Intravenous levetiracetam, a second-generation anticonvulsant was approved by the FDA in 2006 in patients 16 years and older as an alternative when oral treatment is not an option. Data have been published showing that intravenous levetiracetam is safe and efficacious, and can be used in an acute inpatient setting. This current review will discuss the recent data about the safety and tolerability of intravenous levetiracetam in children and neonates, and emphasize the need for a larger prospective multicenter trial to prove the efficacy of this agent in acute seizure management.

Tolerability, safety, and side effects of levetiracetam versus phenytoin in intravenous and total prophylactic regimen among craniotomy patients: a prospective randomized study

PURPOSE

Practical choice in parenteral antiepileptic drugs (AEDs) remains limited despite formulation of newer intravenous agents and requirements of special patient groups. This study aims to compare the tolerability, safety, and side effect profiles of levetiracetam (LEV) against the standard agent phenytoin (PHT) when given intravenously and in total regimen for seizure prophylaxis in a neurosurgical setting.

METHODS

This prospective, randomized, single-center study with appropriate blinding comprised evaluation pertaining to intravenous use 3 days following craniotomy and at discharge, and to total intravenous-plus-oral AED regimen at 90 days. Primary tolerability end points were discontinuation because of side effect and first side effect. Safety combined end point was major side effect or seizure. Seizure occurrence and side effect profiles were compared as secondary outcomes.

KEY FINDINGS

Of 81 patients randomized, 74 (36 LEV, 38 PHT) received parenteral AEDs. No significant difference attributable to intravenous use was found between LEV and PHT in discontinuation because of side effect (LEV 1/36, PHT 2/38, p = 1.00) or number of patients with side effect (LEV 1/36, PHT 4/38, p = 0.36). No significant difference was found between LEV and PHT total intravenous-plus-oral regimen in discontinuation because of side effect (hazard ratio [HR] 0.78, 95% confidence interval [CI] 0.21-2.92, p = 0.72) or number of patients with side effect (HR 1.51, 95% CI 0.77-2.98, p = 0.22). More patients assigned PHT reached the undesirable clinical end point for safety of major side effect or seizure (HR 0.09, 95% CI 0.01-0.70, p = 0.002). Seizures occurred only in patients assigned PHT (n = 6, p = 0.01). Although not significant, trends were observed for major side effect in more patients assigned PHT (p = 0.08) and mild side effect in more assigned LEV (p = 0.09).

SIGNIFICANCE

Both LEV and PHT are well-tolerated perioperatively in parenteral preparation, and in total intravenous-plus-oral prophylactic regimen. Comparative safety and differing side effect profile of intravenous LEV supports use as an alternative to intravenous PHT.

Intravenous and oral levetiracetam in patients with a suspected primary brain tumor and symptomatic seizures undergoing neurosurgery: the HELLO trial

BACKGROUND

Levetiracetam (LEV) is a newer anticonvulsant with a favorable safety profile. There seem to be no relevant drug interactions, and an intravenous formulation is available. Therefore, LEV might be a suitable drug for the perioperative anticonvulsive therapy of patients with suspected brain tumors undergoing neurosurgery.

METHODS

In this prospective study (NCT00571155) patients with suspected primary brain tumors and tumor-related seizures were perioperatively treated with oral and intravenous LEV up to 4 weeks before and until 4 weeks after a planned neurosurgical procedure.

FINDINGS

Thirty patients with brain tumor-related seizures and intended neurosurgery were included. Three patients did not undergo the scheduled surgery after enrollment, and two patients were lost to follow-up. Therefore, 25 patients were fully evaluable. After initiation of therapy with LEV, 100% of the patients were seizure-free in the pre-surgery phase (3 days up to 4 weeks before surgery), 88% in the 48 h post-surgery phase and 84% in the early follow-up phase (48 h to 4 weeks post surgery). Treatment failure even after dose escalation to 3,000 mg/day occurred in three patients. No serious adverse events related to the treatment with LEV occurred.

CONCLUSION

Our data show the feasibility and safety of oral and intravenous LEV in the perioperative treatment of tumor-related seizures. Although this was a single arm study, the efficacy of LEV appears promising. Considering the side effects and interactions of other anticonvulsants, LEV seems to be a favorable option in the perioperative treatment of brain tumor-related seizures.

Comparative monotherapy trials and the clinical treatment of epilepsy

Comparison of Levetiracetam and Controlled-Release Carbamazepine in Newly Diagnosed Epilepsy. Brodie MJ, Perucca E, Ryvlin P, Ben-Menachem E, Meencke HJ; Levetiracetam Monotherapy Study Group. Neurology 2007;68(6):402–408. OBJECTIVE: We report the results of a prospective study of the efficacy and tolerability of levetiracetam, a new antiepileptic drug witha unique mechanism of action, in comparison with controlled-release carbamazepine as first treatment in newly diagnosed epilepsy. METHODS: Adults with 2 partial or generalized tonic–clonic seizures in the previous year were randomly assigned to levetiracetam (500 mg twice daily, n = 288) or controlled-release carbamazepine (200 mg twice daily, n = 291) in a multicenter, double-blind, noninferiority, parallel-group trial. If a seizure occurred within 26 weeks of stabilization, dosage was increased incrementally to a maximum of levetiracetam 1,500 mg twice daily or carbamazepine 600 mg twice daily. Patients achieving the primary endpoint (6-month seizure freedom) continued on treatment for a further 6-month maintenance period. RESULTS: At per-protocol analysis, 73.0% (56.6%) of patients randomized to levetiracetam and 72.8% (58.5%) receiving controlled-release carbamazepine were seizure free at the last evaluated dose (adjusted absolute difference 0.2%, 95% CI – 7.8% to 8.2%) for 6 months (1 year). Of all patients achieving 6-month (1-year) remission, 80.1% (86.0%) in the levetiracetam group and 85.4% (89.3%) in the carbamazepine group did so at the lowest dose level. Withdrawal rates for adverse events were 14.4% with levetiracetam and 19.2% with carbamazepine. CONCLUSIONS: Levetiracetam and controlled-release carbamazepine produced equivalent seizure freedom rates in newly diagnosed epilepsy at optimal dosing in a setting mimicking clinical practice. This trial has confirmed in a randomized, double-blind setting previously uncontrolled observations that most people with epilepsy will respond to their first-ever antiepileptic drug at low dosage.

Levetiracetam compared to valproic acid: plasma concentration levels, adverse effects and interactions in aneurysmal subarachnoid hemorrhage

OBJECTIVE

Both valproic acid and levetiracetam are anti-epileptic drugs, often used either alone or in combination. The present study compares valproate (VPA) with levetiracetam (LEV) as an intravenous (i.v.) anticonvulsant treatment in intensive care patients suffering from aneurysmal subarachnoid hemorrhage (aSAH) with a high risk of seizures.

PATIENTS AND METHODS

A prospective, single-center patient registry of 35 intensive care unit (ICU) patients with onset seizure and/or high risk of seizures underwent an anticonvulsive, first-line single treatment regimen either with VPA or LEV. Plasma concentrations (pc), interactions between drugs in the ICU context, adverse effects and seizure occurrences were observed and recorded.

RESULTS

A significant decrease in the pc in patients treated with LEV was observed after changing from intravenous (160±51μmol/l) to enteral liquid application (113±58μmol/l), corresponding to a 70.3% bioavailability for enteral liquid applications. The pc in VPA patients decreased significantly, from (491±138μmol/l) to (141±50μmol/l), after adding meropenem to the therapy (p<0.05). Three epileptic seizures occurred during anticonvulsive therapy in the LEV group, and two in the VPA group, including one non-convulsive status epilepticus (NCSE).

CONCLUSION

Though this finding needs further verification, the enteral liquid application of levetiracetam seems to be associated with lower bioavailability than the common oral application of levetiracetam. The use of the antibiotic drug meropenem together with valproic acid leads to lower pc levels in patients treated with of valproic acid. For clinical practice, this indicates the need to monitor the levels of valproic acid in combination with meropenem.

Rapid infusion of a loading dose of intravenous levetiracetam with minimal dilution: a safety study

Intravenous antiepileptic drugs are required in patients needing urgent treatment or unable to take oral medication. The safety of intravenous levetiracetam has been established in prospective studies of adult epilepsy and healthy participants. The authors performed a prospective, single-center study to evaluate the safety of a rapid loading dose of intravenous levetiracetam. Patients were divided into 3 equal dosing groups (N = 15 each): 20, 40, and 60 mg/kg (corresponding to maximum doses of 1, 2, and 3 g). Electrocardiogram and safety assessment were performed during the infusion. Ages were 4 to 32 years. Postinfusion serum levetiracetam concentrations were 14 to 189 microg/mL. There were no significant changes in blood pressure, no local infusion site reactions, and no electrocardiogram abnormalities. The authors concluded that high serum levels of parenteral levetiracetam can be achieved rapidly and safely, in a small infusion volume. This finding has important implications for the treatment of status epilepticus.

Role of intravenous levetiracetam in acute seizure management of children

Status epilepticus is defined as a seizure lasting beyond 30 minutes. Children with intractable epilepsy undergo frequent hospital admissions secondary to status epilepticus or because of acute exacerbation of seizures. Intravenous levetiracetam became available in August 2006 for use in patients aged above 16 years. There are insufficient data about the efficacy and safety of intravenous levetiracetam in children. We retrospectively analyzed data from children treated with intravenous levetiracetam for status epilepticus and acute exacerbation of seizures. We acquired data from our institution's electronic medical records concerning patients with status epilepticus and acute exacerbation of seizures who received intravenous levetiracetam. Thirty-two patients (age range, 2 months to 18 years) had received a levetiracetam load of 25-50 mg/kg for status epilepticus. There were 17 (53.1%) males and 15 (46.8%) females. Response to intravenous levetiracetam in all patients was favorable. Status epilepticus ceased clinically and electrographically. Eighteen patients (56.5%) received intravenous levetiracetam after receiving fosphenytoin and Ativan with no response. No serious side effects were evident. Fifteen patients (46.8%) were discharged on levetiracetam monotherapy, and 9 (28.1%) received levetiracetam as adjunctive therapy after discharge from the hospital. Intravenous levetiracetam can be used adjunctively or as monotherapy in children with status epilepticus and acute exacerbation of seizures.

Intravenous levetiracetam as treatment for status epilepticus

There are established drugs for the treatment of status epilepticus (SE) but their potentially hazardous side-effects are well known. Levetiracetam (LEV) is a novel anticonvulsant available for intravenous (i.v.) application. It could be an alternative when standard drugs fail or should be avoided. We retrospectively identified patients from two German teaching hospitals who were treated with LEV i.v. for SE. Their charts were reviewed regarding sociodemographic data, type, etiology, onset and duration of SE, dose of LEV, concurrent antiepileptic drugs (AED) treatment, tolerability, and outcome. Thirty-two patients (15 female) were found who were treated with i.v. LEV for SE (median age 71 years). Two patients were exclusively treated with LEV. Eight received a low and further 20 patients a high dose of benzodiazepines before LEV. Two patients were treated with LEV to enable discontinuation of narcosis. SE was generalized convulsive in five, nonconvulsive in 20, and simple focal in seven patients. Etiology was acute 13 times and remote symptomatic 16 times; three SE were of unknown etiology. Therapy was initiated within a median time of 3 h and LEV i.v. was applied within a median time of 6 h. Median LEV bolus was 2,000 mg; median total dose on day 1 was 3,500 mg. Benzodiazepines plus i.v. LEV terminated SE in 23 patients without application of additional anticonvulsants, 10 within 30 min. LEV could not terminate SE in seven patients. We documented nausea and emesis in one and elevation of liver enzymes in another patient that were likely to be attributed to LEV. LEV i.v. seems to be safe with relevant efficiency for the treatment of SE in elderly and multimorbid patients when comorbidity and respiratory insufficiency precludes high doses of benzodiazepines or phenytoin.

New treatment options in status epilepticus: a critical review on intravenous levetiracetam

The effectiveness of Levetiracetam (LEV) in the treatment of focal and generalised epilepsies is well established. LEV has a wide spectrum of action, good tolerability and a favourable pharmacokinetic profile. An injectable formulation has been released as an intravenous (IV) infusion in 2006 for patients with epilepsy when oral administration is temporarily not feasible. Bioequivalence to the oral preparation has been demonstrated with good tolerability and safety enabling a smooth transition from oral to parenteral formulation and vice versa. Although IV LEV is not licensed for treatment of status epilepticus (SE), open-label experience in retrospective case series is accumulating. Until now (August 2008) 156 patients who were treated with IV LEV for various forms of SE have been reported with an overall success rate of 65.4%. The most often used initial dose was 2000-3000 mg over 15 minutes. Adverse events were reported in 7.1%, and were mild and transient. Although IV LEV is an interesting alternative for the treatment of SE due to the lack of centrally depressive effects and low potential of drug interactions, one has to be aware of the nonrandomised retrospective study design, the heterogenous patient population and treatment protocols, and the publication bias inherent in these type of studies. Only a large randomised controlled trial with an adequate comparator will reveal the efficacy and effectiveness of this promising new IV formulation.

Safety and pharmacokinetics of intravenous levetiracetam infusion as add-on in status epilepticus

PURPOSE

To evaluate the feasibility and safety of intravenous (iv) levetiracetam (LEV) added to the standard therapeutic regimen in adults with status epilepticus (SE), and as secondary objective to assess a population pharmacokinetic (PK) model for ivLEV in patients with SE.

METHODS

In 12 adults presenting with SE, 2,500 mg ivLEV was added as soon as possible to standardized protocol, consisting of iv clonazepam and/or rectal diazepam, as needed followed by phenytoin or valproic acid. ivLEV was administered over approximately 5 min, in general after administration of clonazepam, regardless the need for further treatment. During 24-h follow-up, patients were observed for any clinically relevant side-effects. Blood samples for PK analysis were available in 10 patients. A population PK model was developed by iterative two-stage Bayesian analysis and compared to PK data of healthy volunteers.

RESULTS

Eleven patients with a median age of 60 years were included in the per protocol analysis. Five were diagnosed as generalized-convulsive SE, five as partial-convulsive SE, and one as a nonconvulsive SE. The median time from hospital admission to ivLEV was 36 min. No serious side effects could be related directly to the administration of ivLEV. During PK analysis, four patients showed a clear distribution phase, lacking in the others. The PK of the population was best described by a two-compartment population model. Mean (standard deviation, SD) population parameters included volume of distribution of central compartment: 0.45 (0.084) L/kg; total body clearance: 0.0476 (0.0147) L/h/kg; distribution rate constants, central to peripheral compartment (k(12)): 0.24 (0.12)/h, and peripheral to central (k(21)): 0.70 (0.22)/h. Mean maximal plasma concentration was 85 (19) mg/L.

DISCUSSION

The addition of ivLEV to the standard regimen for controlling SE seems feasible and safe. PK data of ivLEV in patients with SE correspond to earlier values derived from healthy volunteers, confirming a two-compartment population model.

Levetiracetam in the treatment of epilepsy

Epilepsy is a common chronic disorder that requires long-term antiepileptic drug therapy. Approximately one half of patients fail the initial antiepileptic drug and about 35% are refractory to medical therapy, highlighting the continued need for more effective and better tolerated drugs. Levetiracetam is an antiepileptic drug marketed since 2000. Its novel mechanism of action is modulation of synaptic neurotransmitter release through binding to the synaptic vesicle protein SV2A in the brain. Its pharmacokinetic advantages include rapid and almost complete absorption, minimal insignificant binding to plasma protein, absence of enzyme induction, absence of interactions with other drugs, and partial metabolism outside the liver. The availability of an intravenous preparation is yet another advantage. It has been demonstrated effective as adjunctive therapy for refractory partial-onset seizures, primary generalized tonic-clonic seizures, and myoclonic seizures of juvenile myoclonic epilepsy. In addition, it was found equivalent to controlled release carbamazepine as first-line therapy for partial-onset seizures, both in efficacy and tolerability. Its main adverse effects in randomized adjunctive trials in adults have been somnolence, asthenia, infection, and dizziness. In children, the behavioral adverse effects of hostility and nervousness were also noted. Levetiracetam is an important addition to the treatment of epilepsy.

Intravenous levetiracetam in children with epilepsy

Intravenous levetiracetam recently became available for use in patients aged >16 years. There are few data about its safety and efficacy in children. We retrospectively analyzed data from children treated with intravenous levetiracetam. Ten patients (6 female, 4 male), aged 3 weeks to 19 years, were treated with intravenous levetiracetam at a mean dose of 50.5 mg/kg/day for a mean duration of 4.9 days. Four patients received intravenous levetiracetam for acute repetitive seizures/status epilepticus, and three as replacement for oral levetiracetam because administration of oral levetiracetam was temporarily infeasible. One patient each received intravenous levetiracetam for seizure prophylaxis during brain biopsy, as maintenance treatment after acute seizures, and as substitute for sodium valproate. Three of four patients with acute repetitive seizures/status epilepticus became seizure-free; the fourth patient had a partial reduction in seizure frequency. All three patients who received intravenous levetiracetam as substitute for oral levetiracetam tolerated the switch well. The other three patients were seizure-free on intravenous levetiracetam. No serious adverse effects were observed, and all patients completed treatment with intravenous levetiracetam for the intended period. Intravenous levetiracetam may be effective in various clinical situations requiring intravenous administration of an antiepileptic drug.

Treatment of acute seizures and status epilepticus

Overt status epilepticus and persistent obtundation after a witnessed clinical seizure are neurologic emergencies. Early recognition and intervention in the electroclinical syndrome of status epilepticus reduces morbidity, although treatment of the underlying etiology is also critical. This review outlines key concepts related to status epilepticus, delineates an approach to the early management of status epilepticus, and highlights novel but practical approaches in the evaluation and treatment of refractory status epilepticus, emphasizing the use of a treatment algorithm. This review is written from the perspective of the intensive care unit clinician, and the approach and opinions expressed stem from clinical experience and review of the current literature. Particular attention is given to an overall approach to the management of convulsive status epilepticus in adults and older children as well as exploring novel approaches and diagnostic tools that may prove useful in difficult-to-control status epilepticus.

Monotherapy for partial epilepsy: focus on levetiracetam

Levetiracetam (LEV), the S-enantiomer of alpha-ethyl-2-oxo-1-pyrollidine acetamide, is a recently licensed antiepileptic drug (AED) for adjunctive therapy of partial seizures. Its mechanism of action is uncertain but it exhibits a unique profile of anticonvulsant activity in models of chronic epilepsy. Five randomized, double-blind, placebo-controlled trials enrolling adult or pediatric patients with refractory partial epilepsy have demonstrated the efficacy of LEV as adjunctive therapy, with a responder rate (>/=50% reduction in seizure frequency) of 28%-45%. Long-term efficacy studies suggest retention rates of 60% after one year, with 13% of patients seizure-free for 6 months of the study and 8% seizure-free for 1 year. More recent studies illustrated successful conversion to monotherapy in patients with refractory epilepsy, and its effectiveness as a single agent in partial epilepsy. LEV has also efficacy in generalized epilepsies. Adverse effects of LEV, including somnolence, lethargy, and dizziness, are generally mild and their occurrence rate seems to be not significantly different from that observed in placebo groups. LEV also has no clinically significant pharmacokinetic interactions with other AEDs, or with commonly prescribed medications. The combination of effective antiepileptic properties with a relatively mild adverse effect profile makes LEV an attractive therapy for partial seizures.

Modeling and simulation of intravenous levetiracetam pharmacokinetic profiles in children to evaluate dose adaptation rules

PURPOSE

To develop a pharmacokinetic model for intravenous levetiracetam in children, based on adult intravenous data and pediatric oral data.

METHODS

Data from two adult Phase-I studies in which levetiracetam was given intravenously were utilized to develop the adult population pharmacokinetic two-compartment intravenous model. After model qualification, combination with an existing pediatric one-compartment oral population pharmacokinetic model enabled simulation of twice-daily intravenous infusions of levetiracetam in children. Median and 90% confidence intervals for C(trough), C(max) (end of infusion) and AUC(tau) were simulated for 2000 children and compared to the values observed in adults.

RESULTS

The population pharmacokinetic two-compartment model successfully described intravenous levetiracetam pharmacokinetics in healthy adults. After combination with the oral pediatric population model, steady-state concentrations at the end of 15-, 30- and 60 min b.i.d. levetiracetam intravenous infusions in children were predicted to be 29-41, 17-24 and 6-13% higher than those observed after oral dosing of 30 mg/kg b.i.d. Concentrations returned to the range of oral exposures within 1h after the infusion peak. The combined model predicted that steady-state peak plasma concentrations and AUC(tau) in children receiving 30 mg/kg twice daily as 15 min intravenous infusions were within the range of predicted and observed C(max,ss) and AUC(tau )values of adults receiving 15 min intravenous infusions of 1500 mg levetiracetam.

CONCLUSIONS

The simulations suggest that levetiracetam may be administered intravenously in children as 15 min infusions.