[Treatment of epilepsy with third-line antiepileptic drugs: felbamate, tiagabine, and sulthiame]

Sulthiame monotherapy for epilepsy

BACKGROUND

This is an updated version of the original Cochrane Review published in 2014. Epilepsy is a common neurological condition characterised by recurrent seizures. Pharmacological treatment remains the first choice to control epilepsy. Sulthiame (STM) is widely used as an antiepileptic drug in Europe and Israel. In this review, we have presented a summary of evidence for the use of STM as monotherapy in epilepsy.

OBJECTIVES

To assess the efficacy and side effect profile of STM as monotherapy when compared with placebo or another antiepileptic drug for people with epilepsy.

SEARCH METHODS

We searched the following databases on 13 April 2020: the Cochrane Register of Studies (CRS Web), MEDLINE (Ovid, 1946 to 10 April 2020). CRS Web includes randomised or quasi-randomised controlled trials from PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform, the Cochrane Central Register of Controlled Trials (CENTRAL), and the specialised registers of Cochrane Review Groups including Cochrane Epilepsy. We imposed no language restrictions. We contacted the manufacturers of STM and researchers in the field to ask about ongoing and unpublished studies.

SELECTION CRITERIA

Randomised controlled monotherapy trials of STM in people of any age with epilepsy of any aetiology.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. Two review authors independently selected trials for inclusion and extracted the relevant data. We assessed the following outcomes: treatment withdrawal; seizure-free at six months; adverse effects; and quality of life scoring. We conducted the primary analyses by intention-to-treat where possible, and presented a narrative analysis of the data.

MAIN RESULTS

We included four studies involving a total of 355 participants: three studies (209 participants) with a diagnosis of benign epilepsy of childhood with centrotemporal spikes (BECTS), and one study (146 participants) with a diagnosis of generalised tonic-clonic seizures (GTCS). STM was given as monotherapy compared with placebo and with levetiracetam in the BECTS studies, and compared with phenytoin in the GTCS study. An English translation of the full text of one of the BECTS studies could not be found, and analysis of this study was based solely on the English translation of the abstract. For the primary outcome, the total number of dropouts caused either by seizure recurrence or adverse reaction was significantly higher in the levetiracetam treatment arm compared to the STM treatment arm (RR 0.32, 95% Cl 0.10 to 1.03; 1 study, 43 participants; low-certainty evidence). For the secondary outcomes for this comparison, results for seizure freedom were inconclusive (RR 1.12, 95% Cl 0.88 to 1.44; 1 study, 43 participants; low-certainty evidence). Reporting of adverse effects was incomplete. Participants receiving STM were significantly less likely to develop gingival hyperplasia than participants receiving phenytoin in the GTCS study (RR 0.03, 95% CI 0.00 to 0.58; 1 study, 146 participants; low-certainty evidence). No further statistically significant adverse events were noted when STM was compared with phenytoin or placebo. The most common adverse events were related to behavioural disturbances when STM was compared with levetiracetam (RR 0.95, 95% Cl 0.59 to 1.55; 1 study, 43 participants; low-certainty evidence), with the same incidence in both groups. No data were reported for quality of life. Overall, we assessed one study at high risk of bias and one study at unclear bias across the seven domains, mainly due to lack of information regarding study design. Only one trial reported effective methods for blinding. The risk of bias assessments for the other two studies ranged from low to high. We rated the overall certainty of the evidence for the outcomes as low using the GRADE approach.

AUTHORS' CONCLUSIONS

This review provides insufficient information to inform clinical practice. Small sample sizes, poor methodological quality, and lack of data on important outcome measures precluded any meaningful conclusions regarding the efficacy and tolerability of sulthiame as monotherapy in epilepsy. More trials, recruiting larger populations, over longer periods, are needed to determine whether sulthiame has a clinical use.

Sulthiame add-on therapy for epilepsy

BACKGROUND

This is an updated version of the Cochrane Review previously published in the Cochrane Database of Systematic Reviews 2015, Issue 10. Epilepsy is a common neurological condition, characterised by recurrent seizures. Most people respond to conventional antiepileptic drugs, however, around 30% will continue to experience seizures, despite treatment with multiple antiepileptic drugs. Sulthiame, also known as sultiame, is a widely used antiepileptic drug in Europe and Israel. We present a summary of the evidence for the use of sulthiame as add-on therapy in epilepsy.

OBJECTIVES

To assess the efficacy and tolerability of sulthiame as add-on therapy for people with epilepsy of any aetiology compared with placebo or another antiepileptic drug.

SEARCH METHODS

For the latest update, we searched the Cochrane Register of Studies (CRS Web), which includes the Cochrane Epilepsy Group's Specialized Register and CENTRAL (17 January 2019), MEDLINE Ovid (1946 to January 16, 2019), ClinicalTrials.gov and the WHO ICTRP Search Portal (17 January 2019). We imposed no language restrictions. We contacted the manufacturers of sulthiame, and researchers in the field to seek any ongoing or unpublished studies.

SELECTION CRITERIA

Randomised controlled trials of add-on sulthiame, with any level of blinding (single, double or unblinded) in people of any age, with epilepsy of any aetiology.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, and extracted relevant data. We assessed these outcomes: (1) 50% or greater reduction in seizure frequency between baseline and end of follow-up; (2) complete cessation of seizures during follow-up; (3) mean seizure frequency; (4) time-to-treatment withdrawal; (5) adverse effects; and (6) quality of life. We used intention-to-treat for primary analyses. We presented results as risk ratios (RR) with 95% confidence intervals (CIs). However, due to the paucity of trials, we mainly conducted a narrative analysis.

MAIN RESULTS

We included one placebo-controlled trial that recruited 37 infants with newly diagnosed West syndrome. This trial was funded by DESITIN Pharma, Germany. During the study, sulthiame was given as an add-on therapy to pyridoxine. No data were reported for the outcomes: 50% or greater reduction in seizure frequency between baseline and end of follow-up; mean seizure frequency; or quality of life. For complete cessation of seizures during a nine-day follow-up period for add-on sulthiame versus placebo, the RR was 11.14 (95% CI 0.67 to 184.47; very low-certainty evidence), however, this difference was not shown to be statistically significant (P = 0.09). The number of infants experiencing one or more adverse events was not significantly different between the two treatment groups (RR 0.85, 95% CI 0.44 to 1.64; very low-certainty evidence; P = 0.63). Somnolence was more prevalent amongst infants randomised to add-on sulthiame compared to placebo, but again, the difference was not statistically significant (RR 3.40, 95% CI 0.42 to 27.59; very low-certainty evidence; P = 0.25). We were unable to conduct meaningful analysis of time-to-treatment withdrawal and adverse effects due to incomplete data.

AUTHORS' CONCLUSIONS

Sulthiame may lead to a cessation of seizures when used as an add-on therapy to pyridoxine in infants with West syndrome, however, we are very uncertain about the reliability of this finding. The included study was small and had a significant risk of bias, largely due to the lack of details regarding blinding and the incomplete reporting of outcomes. Both issues negatively impacted the certainty of the evidence. No conclusions can be drawn about the occurrence of adverse effects, change in quality of life, or mean reduction in seizure frequency. No evidence exists for the use of sulthiame as an add-on therapy in people with epilepsy outside West syndrome.Large, multi-centre randomised controlled trials are needed to inform clinical practice, if sulthiame is to be used as an add-on therapy for epilepsy.

Sulthiame add-on therapy for epilepsy

BACKGROUND

Epilepsy is a common neurological condition characterised by recurrent seizures. Most patients respond to conventional antiepileptic drugs, however, around 30% will continue to experience seizures despite multiple antiepileptic drugs. Sulthiame, also known as sultiame, is a widely used antiepileptic drug in Europe and Israel. We present a summary of the evidence for the use of sulthiame as add-on therapy in epilepsy.

OBJECTIVES

To compare the efficacy and side-effect profile of sulthiame as add-on therapy compared with placebo or another antiepileptic drug.

SEARCH METHODS

We searched the Cochrane Epilepsy Group's Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, ClinicalTrials.gov and the WHO ICTRP Search Portal on 11 August 2015. No language restrictions were imposed. We contacted the manufacturers of sulthiame and researchers in the field to seek any ongoing or unpublished studies.

SELECTION CRITERIA

Randomised controlled add-on trials of sulthiame in people of any age with epilepsy of any aetiology.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted relevant data. The following outcomes were assessed: 1) reduction in seizure frequency of 50% or greater between baseline and end of follow-up; 2) complete cessation of seizures during follow-up; 3) mean seizure frequency; 4) time to treatment withdrawal; 5) adverse drug effects; and 6) quality of life scoring. Primary analyses were intention-to-treat. We present a narrative analysis.

MAIN RESULTS

We included one trial with 37 participants with a new diagnosis of West syndrome. Sulthiame was given as an add-on therapy to pyridoxine. No data were reported for outcomes 1), 3) or 6). Overall risk ratio with 95% confidence intervals (CI) for complete cessation of seizures during a nine-day follow-up period versus placebo was 0.71 (95% CI 0.53 to 0.96). Meaningful analysis of time to treatment withdrawal and adverse drug effects was not possible due to incomplete data.

AUTHORS' CONCLUSIONS

Sulthiame may lead to a cessation of seizures when used as an add-on therapy to pyridoxine in patients with West syndrome. The included study was small and had a significant risk of bias which limits the impact of the evidence. No conclusions can be drawn about the occurrence of adverse drug effects, change in quality of life or mean reduction in seizure frequency. No evidence exists for the use of sulthiame as an add-on therapy in patients with epilepsy outside West syndrome. Large, multi-centre randomized controlled trials are necessary to inform clinical practice if sulthiame is to be used as an add-on therapy for epilepsy.

Sulthiame monotherapy for epilepsy

BACKGROUND

Epilepsy is a common neurological condition characterised by recurrent seizures. Sulthiame (STM) is widely used as an antiepileptic drug in Europe and Israel. In this review, we present a summary of evidence for the use of STM as monotherapy in epilepsy.

OBJECTIVES

To examine the efficacy and side effect profile of STM as monotherapy when compared with placebo or another antiepileptic drug.

SEARCH METHODS

We searched the Cochrane Epilepsy Group Specialised Register (24 October 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 9), MEDLINE Ovid (1946 to 24 October 2013), SCOPUS (1823 to 24 October 2013), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal (28 October 2013) and ClinicalTrials.gov (28 October 2013). We imposed no language restrictions. We contacted the manufacturers of STM and researchers in the field to ask about ongoing and unpublished studies.

SELECTION CRITERIA

Randomised controlled monotherapy trials of STM in people of any age with epilepsy of any aetiology.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted the relevant data.The following outcomes were assessed: (1) time to treatment failure; (2) time to 12-month remission; (3) proportion seizure free at 12 months; (4) adverse effects; and (5) quality of life scoring. Primary analyses were intention-to-treat when possible. A narrative analysis of the data was presented.

MAIN RESULTS

Two studies representing 100 participants with a diagnosis of benign epilepsy of childhood with centrotemporal spikes (BECTS) and one study representing 146 participants with a diagnosis of generalised tonic-clonic seizures (GTCS) were included. STM was given as monotherapy compared with placebo in the BECTS studies and compared with phenytoin in the GTCS study. An English translation of the full text of one of the BECTS studies could not be found, and analysis of this study was based solely on the English translation of the abstract. No data were reported for outcome (1), (2), (3) or (5). Reporting of adverse effects was incomplete. Participants receiving STM were significantly less likely to develop gingival hyperplasia than were participants receiving phenytoin in the GTCS study (risk ratio (RR) 0.03, 95% confidence interval (CI) 0.00 to 0.58). No further statistically significant adverse events were noted when STM was compared with phenytoin or placebo. Two ongoing studies comparing STM monotherapy versus placebo or levetiracetam in BECTS were identified.

AUTHORS' CONCLUSIONS

Small sample size, poor methodological quality and lack of data on important outcome measures prevent any meaningful conclusions regarding the efficacy and safety of sulthiame as monotherapy in epilepsy.

Sulthiame add-on therapy for epilepsy

BACKGROUND

Epilepsy is a common neurological condition characterised by recurrent seizures. Most patients respond to conventional antiepileptic drugs, however, around 30% will continue to experience seizures despite multiple antiepileptic drugs. Sulthiame is a widely used antiepileptic drug in Europe and Israel. We present a summary of the evidence for the use of sulthiame as add-on therapy in epilepsy.

OBJECTIVES

To compare the efficacy and side-effect profile of sulthiame as add-on therapy compared with placebo or another antiepileptic drug.

SEARCH METHODS

We searched the Cochrane Epilepsy Group's Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and the WHO IRCTRP Search Portal on 28th August 2012. No language restrictions were imposed. We contacted the manufacturers of sulthiame and researchers in the field to seek any ongoing or unpublished studies.

SELECTION CRITERIA

Randomised placebo-controlled add-on trials of sulthiame in people of any age with epilepsy of any aetiology.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted relevant data. The following outcomes were assessed: (1) reduction in seizure frequency of 50% or greater between baseline and end of follow-up (2) complete cessation of seizures during follow-up (3) mean seizure frequency (4) time to treatment withdrawal (5) adverse drug effects (6) quality of life scoring. Primary analyses were intention-to-treat. Narrative analysis is presented.

MAIN RESULTS

One trial was included representing 37 patients with a new diagnosis of West syndrome. Sulthiame was given as an add-on therapy to pyridoxine. No data were reported for outcomes (1), (3) or (6). Overall risk ratio (RR) with 95% confidence intervals (CI) for complete cessation of seizures during a nine-day follow-up period versus placebo was 0.71 (95% CI 0.53 to 0.96). Meaningful analysis of time to treatment withdrawal and adverse drug effects was impossible due to incomplete data.

AUTHORS' CONCLUSIONS

Sulthiame may lead to a cessation of seizures when used as an add-on therapy to pyridoxine in patients with West syndrome. The included study was small and had a significant risk of bias which limits the impact of the evidence. No conclusions can be drawn on the occurrence of adverse drug effects, change in quality of life or mean reduction in seizure frequency. No evidence exists for the use of sulthiame as an add-on therapy in patients with epilepsy outside West syndrome. Large, multi-centre randomised controlled trials are necessary to inform clinical practice if sulthiame is to be used as an add-on therapy for epilepsy.

Treatment strategies for focal epilepsy

BACKGROUND

Treatment strategies for focal epilepsy need to take account of the phase and severity of the seizure disorder, comorbidity, gender and age.

METHODS

Expert review and evaluation of major studies on the treatment of focal epilepsy.

RESULTS

Complete seizure control is most often achieved with antiepileptic drug (AED) monotherapy. In the choice of AED, possible unfavourable endocrine, cognitive or psychiatric adverse effects and their interaction with the non-seizure manifestations of focal epilepsy have to be considered. In women teratogenic risks associated with AED may be relevant. If complete seizure control cannot be achieved with the first three steps of AED treatment, epilepsy surgery becomes the most likely treatment modality to provide complete seizure control. It is proposed that AED combination treatment should be limited to two or three agents to minimize the risk of side effects, especially negative effects on cognition.

CONCLUSIONS

Recent developments in the treatment of focal epilepsy have made it easier to tailor AED therapy to patients' demographic and clinical profile.

Tiagabine: efficacy and safety in partial seizures - current status

Tiagabine hydrochloride (TGB) is a selective gamma-aminobutyric acid (GABA) reuptake inhibitor. TGB is effective as an add-on medication in adults and children 12 years and older in the treatment of partial seizures. Results of nonrandomized add-on trials with TGB show treatment success with seizure reduction of at least 50% in 33% to 46% of patients. In newly diagnosed patients with partial epilepsy, TGB monotherapy was as effective as carbamazepine. Comedication with TGB elevates the risk of nonconvulsive status (7.8% vs 2.7% without TGB). The most common side effects include dizziness/lightheadedness, asthenia/lack of energy and somnolence. TGB has no negative effects on cognition; it does not increase the risk of fractures or rash. TGB may interfere with color perception. TGB presents an intermediate risk for depression in patients with epilepsy (approximately 4%). Regarding the risk of overdose, 96-680 mg TGB (mean 224 mg) caused seizures or coma. TGB is an antiepileptic drug exhibiting a specific anticonvulsive mechanism of action, the efficacy of which is relatively low when used in comedication. Critical side effects, such as the induction of nonconvulsive status epilepticus, further limit its use.

[Treatment of epilepsy in adults. Options and strategies]

Currently, epilepsy can be treated with antiepileptic drugs and, in patients with focal and/or secondarily generalized seizures (focal epilepsy), by means of surgery and vagus nerve stimulation. In the choice of monotherapy possible negative drug related effects on cognitive, endocrine, and psychic symptoms must be considered. Newly developed antiepileptic drugs help to establish an individualized strategy, especially in antiepileptic drug monotherapy. Additionally these antiepileptic drugs have proven to be effective and well tolerated when combined with other antiepileptic drugs. Surgery of focal epilepsy offers the chance of complete cure. Vagus nerve stimulation is a nonmedical treatment option used in addition to antiepileptic drugs in patients with focal epilepsy. Tolerability and safety data should be considered to establish a long-term medical treatment tolerated and accepted by the patient.