Clinical trial NCT02113787: Switchability Study Between Brand and Generic Topiramate
Official title: A Clinical Pharmacokinetics Comparing Brand and Generic Topiramate in Epilepsy Patients : A Open-label,Randomised, Three-period Crossover Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Epilepsy
Keywords: epilepsy
anticonvulsants
generic drugs
Lead sponsor: Seoul National University Hospital
Sponsor class: OTHER
First posted: 2014-04-15
Enrollment: 24
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The purpose of the study is to prove the bioequivalence of brand and generic topiramate.

Detailed description: Generic antiepileptic drugs (AED) achieve blood concentration similar to the brand AED. However, controversies exist about efficacy and safety of substituting generic AEDs. Because even minor absorption and kinetic differences can elicit a breakthrough seizure in patients who are changed to a generic AED from brand AED. Therefore, more ideal evaluation of interchangeability from the brand AEDs to generic formulation of the same drug is three-way or four-way crossover study, which can evaluate within-subject variability in pharmacokinetic and pharmacodynamic. Investigator designed four-way crossover study aimed to assess bioequivalence of brand and generic topiramate, to measure trough serum level , and to evaluate efficacy, tolerability and side effect of generic topiramate.

Eligibility criteria: Inclusion Criteria:

* aged 18-65 years
* Patients with epilepsy who take by topamax 100mg bid or who need to take topamax 100mg bid

Exclusion Criteria:

* poor compliance
* subjects whose dose of antiepileptic drug are changed during the study
* subjects whose seizure is not well-controlled judged by neurologist
* history of any kind of drug allergy
* pregnancy or nursing
* existing or recent significant disease (cardiac, hepatic, or renal disease, severe diabetes mellitus, sepsis, etc.)

Primary outcomes:
measure: To Measure the Area under the plasma concentration versus time curve, serum trough drug level of generic and brand topiramate through pharmacokinetics study.
timeFrame: [ Time Frame: 0.5, 1, 1.5, 2, 3, 4, 6, 8, and 12 hours after taking the brand or generic topiramate during 7 days]
Secondary outcomes:
measure: Number of Participants with Adverse Events as a Measure of Safety and Tolerability of generic topiramate in subjects with epilepsy
timeFrame: 4weeks
Other outcomes:
Locations:
city: Seoul
country: Korea, Republic of
facility: Seoul National University Hospital
Study officials:
affiliation: Seoul National University Hospital
name: Kon Chu, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Bialer M, Midha KK. Generic products of antiepileptic drugs: a perspective on bioequivalence and interchangeability. Epilepsia. 2010 Jun;51(6):941-50. doi: 10.1111/j.1528-1167.2010.02573.x. Epub 2010 Apr 8.
citation: Erickson SC, Le L, Ramsey SD, Solow BK, Zakharyan A, Stockl KM, Harada AS, Curtis B. Clinical and pharmacy utilization outcomes with brand to generic antiepileptic switches in patients with epilepsy. Epilepsia. 2011 Jul;52(7):1365-71. doi: 10.1111/j.1528-1167.2011.03130.x. Epub 2011 Jun 21.