Efficacy and tolerability of levetiracetam as adjunctive therapy in Japanese patients with uncontrolled partial-onset seizures

Efficacy and safety of add-on antiseizure medications for focal epilepsy: A network meta-analysis

OBJECTIVE

Several antiseizure medications (ASMs) have been approved for the treatment of focal epilepsy. However, there is a paucity of evidence on direct comparison of ASMs. We evaluated the comparative efficacy and safety of all approved add-on ASMs for the treatment of focal epilepsy using network meta-analysis.

METHODS

Data through extensive literature search was retrieved from PubMed, Embase, Cochrane, and ClinicalTrial.gov databases using predefined search terms from inception through March 2023. PRISMA reporting guidelines (CRD42023403450) were followed in this study. Efficacy outcomes assessed were ≥50%, ≥75%, and 100% responder rates. Patient retention rate and safety outcomes such as overall treatment-emergent adverse events (TEAEs) and individual TEAEs were assessed. "Gemtc" 4.0.4 package was used to perform Bayesian analysis. Outcomes are reported as relative risks (RRs) and 95% confidence interval (CI).

RESULTS

Literature search retrieved 5807 studies of which, 75 studies were included in the analysis. All ASMs showed significantly higher ≥50% responder rate compared with placebo. Except the ≥75% seizure frequency reduction for zonisamide (2.23; 95% CI: 1.00-5.70) and 100% for rufinamide (2.03; 95% CI: 0.54-11.00), all other interventions showed significantly higher ≥75% and 100% responder rates compared with placebo. Among treatments, significantly higher 100% responder rate was observed with cenobamate compared to eslicarbazepine (10.71; 95% CI: 1.56-323.9) and zonisamide (10.63; 95% CI: 1.37-261.2). All ASMs showed a lower patient retention rate compared to placebo, with the least significant value observed for oxcarbazepine (0.77; 95% CI: 0.7-0.84). Levetiracetam showed a lower risk of incidence (1.0; 95%CI: 0.94-1.1; SUCRA: 0.885067) for overall TEAE compared with other medications.

SIGNIFICANCE

All approved ASMs were effective as add-on treatment for focal epilepsy. Of the ASMs included, cenobamate had the greatest likelihood of allowing patients to attain seizure freedom.

PLAIN LANGUAGE SUMMARY

This article compares the efficacy and safety of antiseizure medications (ASMs) currently available to neurologists in the treatment of epileptic patients. Several newer generation ASMs that have been developed may be as effective or better than the older medications. We included 75 studies in the analysis. In comparison, all drugs improved ≥50%, ≥75% and 100% responder rates compared to control, except for Zonisamide and Rufinamide in the ≥75% and 100% responder rate categories. Retention of patients undergoing treatment was lower in drugs than placebo. All drugs were tolerated, the levetiracetam showed the best tolerability. Cenobamate more likely help completely to reduce seizures.

Efficacy and Safety of Five Broad-Spectrum Antiseizure Medications for Adjunctive Treatment of Refractory Epilepsy: A Systematic Review and Network Meta-analysis

BACKGROUND

Overall, up to one-third of epilepsy patients have drug-resistant epilepsy. However, there was previously no meta-analysis to support the guidelines for broad-spectrum antiseizure medication selection for the adjunctive treatment of refractory epilepsy. In the present meta-analysis, we assessed the efficacy and safety of three second-generation broad-spectrum antiseizure medications, lamotrigine (LTG), levetiracetam (LEV), and topiramate (TPM), and two third-generation broad-spectrum antiseizure medications, perampanel (PER) and lacosamide (LCM), for the adjunctive treatment of refractory epilepsy.

METHODS

We systematically searched PubMed, Embase, and CENTRAL from inception to July 15, 2022. The studies included in the meta-analysis were required to meet the following criteria: (1) be randomized, double-blind clinical trials; (2) include patients aged >2 years with a clinical diagnosis of drug-resistant epilepsy; (3) have at least 8 weeks for the treatment period excluding the titration phase; and (4) report the outcomes of seizure response, seizure freedom and the withdrawal rate due to treatment-emergent adverse effects. Data were extracted, and the risk of bias for each study was assessed by two authors independently using RoB2 tools. We performed the network meta-analysis for each outcome through a group of programs in the mvmeta and network packages in Stata. Relative odds ratios with 95% confidence intervals were calculated as the result of the analyses. The surface under the cumulative ranking curve (SUCRA) and mean ranks were used to rank these treatments.

RESULTS

Forty-two randomized controlled trials (RCTs) (LTG-placebo: n = 6, LEV-placebo: n = 13, TPM-placebo: n = 9, PER-placebo: n = 6, LCM-placebo: n = 7, LEV-TPM: n = 1) with 10257 participants (LTG = 569, LEV = 1626, TPM = 701, PER = 1734, LCM = 1908, placebo = 3719) were included. Levetiracetam had subequal efficacy in 50 % seizure frequency reduction to TPM [odds ratio (OR) 1.00, 95% confidence interval (CI) 0.73-1.38], and LEV had a higher rate of ≥ 50% seizure frequency reduction than LCM (OR 1.49, 95% CI 1.11-2.01) and PER (OR 1.68, 95% CI 1.24-2.29). Levetiracetam was also related to a higher proportion of seizure freedom participants than TPM (OR 1.87, 95% CI 1.20-2.89), PER (OR 2.23, 95% CI 1.12-4.43), and LCM (OR 2.97, 95% CI 1.46-6.05). In addition, LEV was associated with a lower risk of experiencing at least one treatment-emergent adverse event (TEAE) than PER (OR 0.63, 95% CI 0.46-0.85) and TPM (OR 0.51, 95 % CI 0.36-0.72) and a lower proportion of patients experiencing TEAEs leading to discontinuation than PER (OR 0.51, 95% CI 0.27-0.97) and TPM (OR 0.50, 95 % CI 0.27-0.93).

CONCLUSIONS

Third-generation drugs (PER and LCM) had no advantages in terms of efficacy and safety for adjunctive treatment of refractory epilepsy compared with several second-generation drugs (LEV and LTG). Levetiracetam was the priority choice for adjunctive treatment of refractory epilepsy. Perampanel and LCM had no advantages in terms of efficacy and safety among the five drugs.

REGISTRATION

PROSPERO registration number, CRD42022344153; last edited on December 23, 2022.

Is the anticonvulsant activity of levetiracetam dose-dependent?

PURPOSE

Although levetiracetam (LEV) is globally established as a leading antiseizure medication (ASM) it is still a controversial matter whether dose increases correspond with an increased efficacy if LEV in the recommended dose range did not show satisfying efficacy. In our clinical perception we questioned the value of dose increases in such non-responders.

METHODS

In this retrospective monocenter study we analyzed the data of adult people with epilepsies (PWE) with focal-onset seizures who had been treated at the department of adults of the Kork Epilepsy Center between 2009 and 2019, who had been on a stable daily LEV dose and in whom LEV was further increased due to further seizures in spite of baseline LEV in a recommended daily dose range. For reasons of data homogeneity, we included only PWE with at least two definite seizures during the hospital stay under the baseline LEV dose who were treated and observed as in-patients after the increase of LEV for a period at least three-fold longer than the baseline interval before. Additional data acquisition comprised clinical data including adverse events, serum concentrations of LEV and other ASMs, and additional laboratory findings. The primary outcome variable was the change of seizure frequency prior to and after the increase of LEV.

RESULTS

Out of 518 PWE who had been on LEV during their hospital stay, a total of 61 PWE fulfilled the inclusion criteria. After a gradual dose increment, 91,8 % of PWE showed a reduced seizure frequency, 73,8 % had a reduction of seizures of 50 % or more, and 21,3 % were seizure-free during the observation period. A significant seizure reduction could be shown with a seizure count of 2,5/week prior to the increment and 0,7/week after dose increment (p < 0,00001). Seven PWE reported minor adverse events and ten PWE showed slight laboratory changes (within normal levels).

CONCLUSION

Contrary to our long-term clinical impression, LEV dose increments were reasonable and improved the seizure situation in PWE, usually without additional safety hazards.

Levetiracetam add-on for drug-resistant focal epilepsy

BACKGROUND

Drug resistance is common in focal epilepsy. In this update, we summarised the current evidence regarding add-on levetiracetam in treating drug-resistant focal epilepsy. The original review was published in 2001 and last updated in 2012.

OBJECTIVES

To evaluate the effectiveness of levetiracetam when used as an add-on treatment for people with drug-resistant focal epilepsy.

SEARCH METHODS

We searched the Cochrane Register of Studies (CRS Web, which includes the Cochrane Epilepsy Group Specialized Register and CENTRAL), MEDLINE Ovid, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform (ICTRP) to November 2018. We contacted the manufacturers of levetiracetam and researchers in the field to seek any ongoing or unpublished trials.

SELECTION CRITERIA

Randomised, placebo-controlled trials of add-on levetiracetam treatment in people with drug-resistant focal epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trials for bias, extracted data, and evaluated the overall certainty of the evidence. Outcomes investigated included 50% or greater reduction in focal seizure frequency (response), treatment withdrawal, adverse effects (including a specific analysis of changes in behaviour), cognitive effects, and quality of life (QoL). Primary analysis was intention-to-treat. We performed meta-analysis for all outcomes using a Mantel-Haenszel approach and calculated risk ratios (RR), with 95% confidence intervals (CI) for all estimates apart from adverse effects (99% CIs). We assessed heterogeneity using a Chi² test and the I² statistic.

MAIN RESULTS

This update included 14 trials (2455 participants), predominantly possessing low risks of bias. Participants were adults in 12 trials (2159 participants) and children in the remaining two (296 participants). The doses of levetiracetam tested were 500 mg/day to 4000 mg/day in adults, and 60 mg/kg/day in children. Treatment ranged from 12 to 24 weeks. When individual doses were examined, levetiracetam at either 500 mg/day or 4000 mg/day did not perform better than placebo for the 50% or greater reduction in seizure frequency outcome (500 mg: RR 1.60, 95% CI 0.71 to 3.62; P = 0.26; 4000 mg: RR 1.64, 95% CI 0.59 to 4.57; P = 0.34). Levetiracetam was significantly better than placebo at all other individual doses (1000 mg to 3000 mg). RR was significantly in favour of levetiracetam compared to placebo when results were pooled across all doses (RR 2.37, 95% CI 2.02 to 2.78; 14 studies, 2455 participants; moderate-certainty evidence). Dose-response analysis demonstrated that the odds of achieving response (50% or greater reduction in seizure frequency) were increased by nearly 40% (odds ratio (OR) 1.39, 95% CI 1.23 to 1.58) for each 1000 mg increase in dose of levetiracetam. There were important levels of heterogeneity across multiple comparisons. Participants were not significantly more likely to experience treatment withdrawal with levetiracetam than with placebo (pooled RR 1.11, 95% CI 0.89 to 1.40; 13 studies, 2428 participants; high-certainty evidence). Somnolence was the most common adverse effect, affecting 13% of participants, and it was significantly associated with levetiracetam compared to placebo (pooled RR 1.62, 99% CI 1.19 to 2.20; 13 studies, 2423 participants; moderate-certainty evidence). Changes in behaviour were negligible in adults (1% affected; RR 1.79, 99% CI 0.59 to 5.41), but significant in children (23% affected; RR 1.90, 99% CI 1.16 to 3.11). Levetiracetam had a positive effect on some aspects of cognition and QoL in adults and worsened certain aspects of child behaviour.

AUTHORS' CONCLUSIONS

Overall, this review update finds that in both adults and children with drug-resistant focal epilepsy, levetiracetam added on to usual care is more effective than placebo at reducing seizure frequency, it is unlikely to be stopped by patients, and it has minimal adverse effects outside of potential worsening behaviour in children. These findings are unchanged from the previous review update in 2012. This review update contributes two key additional findings: 1. a 500 mg daily dose of levetiracetam is no more effective than placebo at reducing seizures; and 2. the odds of response (50% reduction in seizure frequency) are increased by nearly 40% for each 1000 mg increase in dose of levetiracetam. It seems reasonable to continue the use of levetiracetam in both adults and children with drug-resistant focal epilepsy.

Levetiracetam efficacy in PCDH19 Girls Clustering Epilepsy

BACKGROUND

PCDH19 Girls clustering epilepsy (GCE) has a phenotypic spectrum that includes developmental and epileptic encephalopathy. PCDH19-GCE presents with clusters of seizures in the first years of life. Although patients typically outgrow their seizures, many are left with intellectual disability. Here we retrospectively assess the effect of levetiracetam in two independent cohorts of females with PCDH19-GCE.

METHODS

Cohort A was identified by searching our epilepsy genetics research database for girls with PCDH19-GCE who had trialled levetiracetam. Cohort B consisted of girls aged 2 years or older, including women, participating in an international online questionnaire. Information regarding seizure frequency and levetiracetam use was obtained by in-person patient interview and review of clinical records for cohort A, and by patient report for cohort B.

RESULTS

Cohort A consisted of 17 females, aged 3-37 years, who had a trial of levetiracetam at an average age of 10.7 years. 13/17 females became seizure free for >12 months; while 10/17 remained seizure free for >24 months. Cohort B comprised 62 females, aged 1.5-41 years. 26/62 became seizure free for >12 months, and 19/62 for >24 months on levetiracetam therapy.

DISCUSSION

Levetiracetam was effective in two cohorts of females with PCDH19-GCE where 42% and 76% of females became seizure free for >12 months, respectively. Levetiracetam is an effective therapy for females with PCDH19-GCE and should be considered early in the management of the highly refractory clusters of seizures that characterise this genetic disease.

A meta-analysis of levetiracetam for randomized placebo-controlled trials in patients with refractory epilepsy

OBJECTIVE

The objective of this study was to investigate the efficacy and safety profile of levetiracetam as add-on therapy in patients with refractory epilepsy.

METHODS

Web of Science, MEDLINE (Ovid and PubMed), Cochrane Library, EMBASE, and Google Scholar were systematically searched to identify potential eligible randomized controlled trials by two reviewers independently. Pooled estimates of risk ratios (RRs) for 50%, 75%, and 100% reduction from baseline were calculated using the fixed-effect model or random-effect model. Quality of included studies was assessed with the Cochrane Collaboration's Risk of Bias tool. Serious adverse events and withdrawals induced by interventions and the most common side effects were analyzed.

RESULTS

Seventeen trials with a total of 3,205 participants were included in this meta-analysis, including 14 trials for adulthood and three trials for children. Pooled estimates suggested that levetiracetam was an effective anti-epileptic drug at 1,000-3,000 mg/day (RR =2.00 for 1,000 mg/day, RR =2.68 for 2,000 mg/day, RR =2.18 for 3,000 mg/day) for adults and 60 mg/kg/day (RR =2.00) for children compared to placebo in terms of 50% reduction from baseline. Likewise, as for seizure freedom rate, levetiracetam had an advantage over placebo at 1,000-3,000 mg/day (RR =5.84 for 1,000 mg/day, RR =4.55 for 2,000 mg/day, RR =4.57 for 3,000 mg/day, respectively) for adults and 60 mg/kg/day (RR =4.52) for children. Regarding safety profile, patients treated with levetiracetam had significantly higher occurrence than placebo for somnolence, asthenia, dizziness, infection, nasopharyngitis, anxiety, and irritability; however, most studies reported that these adverse events were mild and transient.

CONCLUSION

Levetiracetam is an effective anti-epileptic drug for both adults and children with generalized or partial-onset refractory seizures at 1,000-3,000 or 60 mg/kg/day, with a favorable adverse event profile.

Levetiracetam for epilepsy: an evidence map of efficacy, safety and economic profiles

OBJECTIVE

To evaluate the efficacy, safety and economics of levetiracetam (LEV) for epilepsy.

MATERIALS AND METHODS

PubMed, Scopus, the Cochrane Library, OpenGrey.eu and ClinicalTrials.gov were searched for systematic reviews (SRs), meta-analyses, randomized controlled trials (RCTs), observational studies, case reports and economic studies published from January 2007 to April 2018. We used a bubble plot to graphically display information of included studies and conducted meta-analyses to quantitatively synthesize the evidence.

RESULTS

A total of 14,803 records were obtained. We included 30 SRs/meta-analyses, 34 RCTs, 18 observational studies, 58 case reports and 2 economic studies after the screening process. The included SRs enrolled patients with pediatric epilepsy, epilepsy in pregnancy, focal epilepsy, generalized epilepsy and refractory focal epilepsy. Meta-analysis of the included RCTs indicated that LEV was as effective as carbamazepine (CBZ; treatment for 6 months: 58.9% vs 64.8%, OR=0.76, 95% CI: 0.50-1.16; 12 months: 54.9% vs 55.5%, OR=1.24, 95% CI: 0.79-1.93), oxcarbazepine (57.7% vs 59.8%, OR=1.34, 95% CI: 0.34-5.23), phenobarbital (50.0% vs 50.9%, OR=1.20, 95% CI: 0.51-2.82) and lamotrigine (LTG; 61.5% vs 57.7%, OR=1.22, 95% CI: 0.90-1.66). SRs and observational studies indicated a low malformation rate and intrauterine death rate for pregnant women, as well as low risk of cognitive side effects. But psychiatric and behavioral side effects could not be ruled out. LEV decreased discontinuation due to adverse events compared with CBZ (OR=0.52, 95% CI: 0.41-0.65), while no difference was found when LEV was compared with placebo and LTG. Two cost-effectiveness evaluations for refractory epilepsy with decision-tree model showed US$ 76.18 per seizure-free day gained in Canada and US$ 44 per seizure-free day gained in Korea.

CONCLUSION

LEV is as effective as CBZ, oxcarbazepine, phenobarbital and LTG and has an advantage for pregnant women and in cognitive functions. Limited evidence supports its cost-effectiveness.

REGISTERED NUMBER

PROSPERO (No CRD 42017069367).

Adjunctive levetiracetam in the treatment of Chinese and Japanese adults with generalized tonic-clonic seizures: A double-blind, randomized, placebo-controlled trial

Objective

To assess the efficacy, safety, and tolerability of adjunctive levetiracetam (LEV) in Chinese and Japanese adults with generalized tonic-clonic (GTC) seizures (N01159; NCT01228747).

Methods

This double-blind, randomized, placebo-controlled, multicenter phase III trial comprised: 4-week retrospective and 4-week prospective baseline, 12-week dose-adjustment, and 16-week evaluation periods. Chinese and Japanese patients ≥16 years old with idiopathic generalized, symptomatic generalized, or undetermined epilepsy with GTC seizures received a single-blind placebo during the prospective baseline, and then were randomized 1:1 to placebo or LEV 1,000 mg/day administered twice daily. Patients reporting GTC seizures up to week 8 had the LEV dosage increased to 3,000 mg/day. The primary efficacy variable was percent reduction from combined baseline in GTC seizures/week during the 28-week treatment period.

Results

Overall, 251 patients were randomized (208 from China; 43 from Japan); 141 (56.2%) completed the 28-week treatment period. Least-squares mean percent reduction from combined baseline in GTC seizures/week (treatment period) was placebo 12.6% versus LEV 68.8% (95% confidence interval, 44.0-68.2; p < 0.0001). GTC seizure frequency reduction occurred in both patients with idiopathic and symptomatic generalized epilepsy. The 50% responder rate (treatment period) was placebo 28.4% versus LEV 77.8%. Freedom from GTC seizures (evaluation period) was placebo 3.1% versus LEV 29.6%. Incidence of treatment-emergent adverse events (TEAEs; treatment period) was placebo 52.0% versus LEV 57.1%; most frequently nasopharyngitis, protein in urine, decreased platelet count, and pyrexia. Incidence of TEAEs leading to discontinuation was 4.8% versus 3.2%; incidence of serious TEAEs was 3.2% versus 0.8% for placebo and LEV, respectively; 3 patients taking placebo died versus none taking LEV.

Significance

In this trial, adjunctive LEV 1,000-3,000 mg/day was effective in reducing GTC seizure frequency in Chinese and Japanese patients ≥16 years old with GTC seizures. Seizure reduction occurred in both patients with idiopathic and symptomatic generalized epilepsy. LEV was well tolerated in this population.

Newer antiepileptic drugs compared to levetiracetam as adjunctive treatments for uncontrolled focal epilepsy: An indirect comparison

PURPOSE

Newer antiepileptic drugs (AEDs), such as Eslicarbazepine (ESL), Lacosamide (LAC), Perampanel (PER) and Brivaracetam (BRV), have been marketed as adjunctive treatments for partial-onset seizures. Our aim was to compare the efficacy and tolerability of newer AEDs with Levetiracetam (LEV), when used as add-on treatments for uncontrolled focal epilepsy.

METHOD

We conducted an online database search on PubMed, Embase, Cochrane Online Library and Clinicaltrials.gov for all available randomized controlled trials (RCTs) investigating the therapeutic effects of newer AEDs or LEV vs placebo. Indirect comparisons for clinical efficacy and tolerability at different doses between the newer AEDs and LEV were then performed using Indirect Treatment Comparison (ITC) software.

RESULTS

Twenty-four RCTs with a total of 8540 patients were included. Compared to LEV, ESL, LAC and BRV did not showed significant difference in efficacy at all dose level. PER showed lower 50% response rates and seizure-free rates at the highest effective recommended dosages. Treatment-emergent adverse events (TEAEs) and withdrawal rates due to adverse events (AEs) of LAC and PER were higher than LEV at the highest effective recommended dosages, and overall AE rates from ESL were higher than LEV.

CONCLUSIONS

Indirect comparisons suggested that ESL, LAC and BRV were not inferior to LEV in efficacy. ESL, LAC and PER may have a possible worse tolerability profile compared to LEV at high dose. But BRV may exhibit a similar tolerability to LEV. Newer AEDs cannot exceed the LEV on efficacy and tolerability.

Can Matching-Adjusted Indirect Comparison Methods Mitigate Placebo Response Differences Among Patient Populations in Adjunctive Trials of Brivaracetam and Levetiracetam?

BACKGROUND AND OBJECTIVE

Patients with focal seizures recruited into adjunctive antiepileptic drug (AED) trials have become more refractory and severe over time; concurrently, placebo responses have increased. To attempt to account for heterogeneity among trials, propensity-score weighted patient-level data were used to indirectly compare placebo responses reported in brivaracetam and levetiracetam trials.

METHODS

Patient-level data from randomised, placebo-controlled brivaracetam (recruited 2007-2014) and levetiracetam (1993-1998) trials were pooled. Consistent inclusion/exclusion criteria were applied and outcomes were defined consistently. Potentially confounding baseline characteristics were adjusted for using propensity score weighting. Weighting success was assessed using placebo response.

RESULTS

In total, 707 and 473 active drug and 399 and 253 placebo patients comprised the brivaracetam and levetiracetam groups, respectively. Before weighting, several baseline variables were significantly different between groups; after weighting, prior vagal nerve stimulation, co-morbid depression and co-morbid anxiety remained different. Before weighting, median seizure frequency reduction was 21.7 and 3.9% in the brivaracetam and levetiracetam placebo arms, respectively; after weighting, median reduction was 15.0 and 6.0%. The comparison of non-randomised groups could be biased by unobserved confounding factors and region of residence. Lifetime AED history was unavailable in the brivaracetam trials and excluded from analysis.

CONCLUSIONS

Placebo responses remained different between brivaracetam and levetiracetam trials after propensity score weighting, indicating the presence of residual confounding factors associated with placebo response in these trials. It therefore remains problematic to conduct reliable indirect comparisons of brivaracetam and levetiracetam given the current evidence base, which may apply to comparisons between other AED trials.