Sultiame

Sultiame pharmacokinetic profile in plasma and erythrocytes after single oral doses: A pilot study in healthy volunteers

A pilot study was conducted aiming at specifying sultiame's pharmacokinetic profile, completed by in vitro assays evaluating the intraerythrocytic transfer of sultiame and by a pharmacokinetic model assessing its distribution. Single oral doses of sultiame (Ospolot^? 50, 100, and 200 mg) were administered in open-label to four healthy volunteers. Serial plasma, whole blood, and urine samples were collected. A spiking experiment was also performed to characterize sultiame's exchanges between plasma and erythrocytes in vitro. Pharmacokinetic parameters were evaluated using standard noncompartmental calculations and nonlinear mixed-effect modeling. The plasma maximal concentrations (C_max ) showed striking nonlinear disposition of sultiame, with a 10-fold increase while doses were doubled. Conversely, whole blood C_max increased less than dose proportionally while staying much higher than in plasma. Quick uptake of sultiame into erythrocytes observed in vivo was confirmed in vitro, with minimal efflux. A two-compartment model with first-order absorption, incorporating a saturable ligand to receptor binding, described the data remarkably well, indicating apparent plasma clearance of 10.0 L/h (BSV: 29%) and distribution volume of 64.8 L; saturable uptake into an intracellular compartment of 3.3 L with a maximum binding capacity of 111 mg accounted for nonlinearities observed in plasma and whole blood concentrations. Pharmacokinetic characteristics of sultiame are reported, including estimates of clearance and volume of distribution that were so far unpublished. The noticeable nonlinearity in sultiame disposition should be taken into account for the design of future studies and the interpretation of therapeutic drug monitoring results.

Sultiame revisited: treatment of refractory absence seizures

Sultiame is recommended for the treatment of benign epilepsy of childhood with centrotemporal spikes, electrical status epilepticus during slow-wave sleep, as well as other genetic (idiopathic) focal epilepsies. Sultiame is not traditionally considered a treatment choice for idiopathic generalised epilepsy, and it does not appear on the list of drugs recommended for treatment of absence seizures. We report the efficacy of sultiame in treating three children with drug-resistant absence seizures and discuss the potential use of sultiame beyond the idiopathic focal epilepsies.

A Randomized Controlled Clinical Trial Exploring Safety and Tolerability of Sulthiame in Sleep Apnea

Rationale: Current therapies for obstructive sleep apnea (OSA) are limited by insufficient efficacy, compliance, or tolerability. An effective pharmacological treatment for OSA is warranted. Carbonic anhydrase inhibition has been shown to ameliorate OSA. Objectives: To explore safety and tolerability of the carbonic anhydrase inhibitor sulthiame (STM) in OSA. Methods: A 4-week double-blind, randomized, placebo-controlled dose-guiding trial was conducted in patients with moderate and/or severe OSA not tolerating positive airway pressure treatment. Measurements and Main Results: Intermittent paresthesia was reported by 79%, 67%, and 18% of patients receiving 400 mg STM (n = 34), 200 mg STM (n = 12), and placebo (n = 22), respectively. Dyspnea was reported after 400 mg STM (18%). Six patients in the higher dose group withdrew because of adverse events. There were no serious adverse events. STM reduced the apnea-hypopnea index from 55.2 to 33.0 events/h (-41.0%) in the 400-mg group and from 61.1 to 40.6 events/h (-32.1%) after 200 mg (P < 0.001 for both). Corresponding placebo values were 53.9 and 50.9 events/h (-5.4%). The apnea-hypopnea index reduction threshold of ?50% was reached in 40% of patients after 400 mg, 25% after 200 mg, and 5% after placebo. Mean overnight oxygen saturation improved by 1.1% after 400 and 200 mg (P < 0.001 and P = 0.034, respectively). Patient-related outcomes were unchanged. Conclusions: STM showed a satisfactory safety profile in moderate and/or severe OSA. STM reduced OSA, on average, by more than 20 events/h, one of the strongest reductions reported in a drug trial in OSA. Larger scale clinical studies of STM in OSA are justified. Clinical trial registered with www.clinicaltrialsregister.eu (2017-004767-13).

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.