perampanel and ezogabine

Ezogabine, clobazam, and perampanel are among the newest antiseizure drugs approved by the Food and Drug Administration between 2011 and 2012. Ezogabine and perampanel are approved for adjunctive treatment of partial epilepsy. Perampanel is also approved for adjunctive treatment of primary generalized tonic-clonic seizures. Ezogabine and perampanel have novel mechanisms of action. Ezogabine binds to voltage-gated potassium channels and increases the M-current thereby causing membrane hyperpolarization. Perampanel is a selective, non-competitive 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)propanoic acid receptor antagonist, which reduces neuronal excitation. Clobazam has been used worldwide since the 1970s and is approved for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome. Clobazam is the only 1,5-benzodiazepine currently in clinical use, which is less sedating than the commonly used 1,4-benzodiazepines. Phase III multicenter, randomized, double-blind, placebo-controlled trials demonstrated efficacy and good tolerability of these 3 new antiepileptic drugs. These drugs represent a welcome addition to the armamentarium of practitioners, but it remains to be seen how they will affect the landscape of pharmacoresistant epilepsy.

Topics: Anticonvulsants; Benzodiazepines; Carbamates; Clobazam; Humans; Nitriles; Phenylenediamines; Pyridones; Treatment Outcome

Mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) is a syndrome that is often refractory to drug treatment. The effects on specific syndromes are not currently available from the pre-marketing clinical development of new AEDs; this does not allow the prediction of whether new drugs will be more effective in the treatment of some patients.. We have reviewed all the existing literature relevant to the understanding of a potential effectiveness in MTLE-HS patients for the latest AEDs, namely brivaracetam, eslicarbazepine, lacosamide, perampanel and retigabine also including the most relevant clinical data and a brief description of their pharmacological profile. Records were identified using predefined search criteria using electronic databases (e.g., PubMed, Cochrane Library Database of Systematic Reviews). Primary peer-reviewed articles published up to the 15 June 2015 were included.. All the drugs considered have the potential to be effective in the treatment of MTLE-HS; in fact, they possess proven efficacy in animal models; currently considered valuable tools for predicting drug efficacy in TLE. Furthermore, for some of these (e.g., lacosamide and eslicarbazepine) data are already available from post-marketing studies while brivaracetam acting on SV2A like levetiracetam might have the same potential effectiveness with the possibility to be more efficacious considering its ability to inhibit voltage gated sodium channels; finally, perampanel and retigabine are very effective drugs in animal models of TLE.

Topics: Acetamides; Anticonvulsants; Carbamates; Clinical Trials as Topic; Dibenzazepines; Epilepsy, Temporal Lobe; Hippocampus; Humans; Lacosamide; Levetiracetam; Nitriles; Phenylenediamines; Piracetam; Pyridones; Sclerosis; Syndrome

This article lays the background for, and discusses the practical issues surrounding, the adjunctive use of the last four antiepileptic drugs (AEDs) to be licensed for the treatment of pharmacoresistant focal seizures in the UK and elsewhere. More than 30% of adolescent and adult patients will not be fully controlled on the currently available therapeutic armamentarium. After not responding to their first three AED schedules, only a handful of patients attained seizure freedom on subsequent regimens. To optimise the response to any new AED in this setting, it is often necessary to reduce the existing drug burden. The pharmacology, tolerability and safety, and everyday use of lacosamide, eslicarbazepine acetate, retigabine (ezogabine) and perampanel will be reviewed and discussed. This will be accompanied by data from prospective audits with each drug undertaken at the Western Infirmary in Glasgow, Scotland, and a report of their successful introduction in an illustrative case. Overall, there is a large variation in the course of refractory epilepsy and the effect of AED therapy on this process seems minimal. Nevertheless, a number of patients will benefit from the introduction of each new AED, with some becoming seizure-free.

Topics: Acetamides; Adult; Aged; Animals; Anticonvulsants; Carbamates; Dibenzazepines; Drug Resistant Epilepsy; Epilepsies, Partial; Female; Humans; Lacosamide; Male; Middle Aged; Nitriles; Phenylenediamines; Pyridones

Complex-partial seizures are frequently resistant to antiepileptic therapy. Two new medications with mechanisms of action novel within the antiepileptic class have recently received approval for the adjunctive treatment of partial (focal) seizures.. A Medline search was conducted to identify preclinical and clinical studies of ezogabine and perampanel. This was supplemented with additional articles obtained from online sources and information provided by the FDA and the manufacturers. The focus of this review is on the safety profiles of ezogabine (retigabine), a novel antiepileptic that targets voltage-gated potassium channels, and perampanel, a noncompetitive α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate glutamate receptor antagonist.. Central nervous system effects are predominant within the adverse event profiles of both ezogabine and perampanel. In addition, ezogabine exerts its inhibitory effects on potassium channels in the urogenital tract potentially resulting in urinary retention and related outcomes. Recent reports of blue discoloration of the skin and in the retinas of long-term ezogabine users have surfaced. Both drugs have demonstrated the ability to induce neuropsychiatric symptoms. Though both are welcome additions to the antiepileptic drug class, additional monitoring, appropriate counseling, and careful selection of patients are warranted to minimize adverse events.

Topics: Anticonvulsants; Carbamates; Drug Monitoring; Drug Resistance; Epilepsy, Complex Partial; Humans; Nitriles; Patient Selection; Phenylenediamines; Potassium Channels, Voltage-Gated; Pyridones; Receptors, AMPA