Levetiracetam, oxcarbazepine, remacemide and zonisamide for drug resistant localization-related epilepsy: a systematic review.
OBJECTIVE
To undertake a systematic review and meta-analysis of placebo controlled add-on trials of levetiracetam, oxcarbazepine, remacemide and zonisamide for patients with drug resistant localization related epilepsy.


METHODS
We searched Medline, The Cochrane Library and contacted the relevant pharmaceutical companies. Outcomes were 50% or greater reduction in seizure frequency and treatment withdrawal for any reason. Data were synthesised in a meta-analysis. The effect of dose was explored in regression models for levetiracetam and remacemide.


RESULTS
We found four trials (1023 patients) of levetiracetam, two (961) of oxcarbazepine, two (388) of remacemide and three (499) of zonisamide. Ignoring dose, the relative risks (95% CI) for a 50% response were 3.78 (2.62-5.44), 2.51 (1.88-3.33), 1.59 (0.91-2.97) and 2.46 (1.61-3.79), respectively. There was evidence for increasing effect with increasing dose for levetiracetam, oxcarbazepine and remacemide. The relative risks for treatment withdrawal were 1.21 (0.88-1.66), 1.72 (1.35-2.18), 1.90 (1.00-3.60) and 1.64 (1.02-2.62), respectively.


CONCLUSIONS
These data suggest a useful effect for levetiracetam, oxcarbazepine and zonisamide. Levetiracetam has the more favourable 'responder-withdrawal ratio' followed by zonisamide and oxcarbazepine.
Marson
A G
AG
Department of Neurological Science, Clinical Sciences Centre for Research and Education, University of Liverpool, Lower Lane, Fazakerley, Liverpool L9 7LJ, UK. a.g.marson@liv.ac.uk
Hutton
J L
JL
Leach
J P
JP
Castillo
S
S
Schmidt
D
D
White
S
S
Chaisewikul
R
R
Privitera
M
M
Chadwick
D W
DW
D000081:Acetamides / Q000627:therapeutic use*; D000927:Anticonvulsants / Q000627:therapeutic use*; D002220:Carbamazepine / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D018849:Controlled Clinical Trials as Topic / Q000706:statistics & numerical data; D004351:Drug Resistance; D004828:Epilepsies, Partial / Q000188:drug therapy*; D006801:Humans; D007555:Isoxazoles / Q000627:therapeutic use*; D000077287:Levetiracetam; D016014:Linear Models; D016015:Logistic Models; D000078330:Oxcarbazepine; D010889:Piracetam / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D000078305:Zonisamide
D000081:Acetamides; D000927:Anticonvulsants; D007555:Isoxazoles; D002220:Carbamazepine; D000077287:Levetiracetam; D000078305:Zonisamide; C067553:remacemide; D000078330:Oxcarbazepine; D010889:Piracetam