ClinicalTrials.gg
CompletedNCT01439438Updated Jun 28, 2017

Topiramate Bioequivalence Study Brazil - Fast

A Phase 1 interventional study of Topiramate coated tablet and Topamax® coated tablet in Epilepsy, Tonic-Clonic, sponsored by GlaxoSmithKline. Completed at 1 site in Brazil. Open to male participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2017-06-28.

Sponsored by GlaxoSmithKline · Phase 1, Interventional, and Other

Phase
Phase 1
Study type
Interventional
Enrollment
26
Allocation
Randomized
Ages
18 Years to 50 Years
Sex
Male
01

Study summary

This study is prospective, open-label, randomized, crossover, single dose, with 02 treatments, 02 sequences and 02 periods. The volunteers received, in each period, the reference or the test formulation, according to the randomization list, under fasting conditions, in order to evaluate if the reference and test formulations are bioequivalent.

Read the detailed description

This study is prospective, open-label, randomized, crossover, single dose, with 02 treatments, 02 seuqences and 02 periods. The objective is to confirm if two formulations of topiramate 100 mg, coated tablet, are bioequivalent, after oral, single-dose administration under fasting conditions. The test product is topiramate 100 mg produced by Dr. Reddy's Laboratories Ltd. and the reference product is Topamax® marketed by Janssen-Cilag Farmacêutica Ltda. Twenty-eight healthy male volunteers were evaluated. The volunteers received, in each period, the test or the reference formulation, according to the randomization list. In each period, blood samples are collected in the following times: 00:00 (prior to the administration of medication); 00:20; 00:40; 01:00; 01:30; 02:00; 02:30; 03:00; 03:30; 04:00; 05:00; 06:00; 08:00; 12:00; 16:00; 20:00; 24:00; 48:00; 72:00; 96:00; 120:00; 144:00; 168:00; 192:00. The comparative bioavailability of the two formulations was evaluated based in statistical comparisons of relevant pharmacokinetic parameters, obtained from data of drug concentrations in blood.

02

Conditions studied

  • Epilepsy, Tonic-Clonic

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03

In context

Epilepsy, Tonic-Clonic

23 studies on the registry are indexed under Epilepsy, Tonic-Clonic; 3 are open to participants now.

This study's enrollment of 26 is below the median of 94 across 20 interventional studies indexed under Epilepsy, Tonic-Clonic.

Browse Epilepsy, Tonic-Clonic studies →

Lead sponsor

GlaxoSmithKline is the lead sponsor of 3,650 studies on the registry; 118 are open to participants now.

Of its 264 completed or terminated interventional studies of FDA-regulated products, 241 (91%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 50 Years
Sexes eligible
Male
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Male
  • Age between 18 and 50 years
  • between 19 and 28,5 kg/m2
  • Good health conditions
  • Capable to understand the study's nature and aim, including risks and adverse effects and with intention to cooperate with the researcher and to act in compliance with requirements of the assay, this will be confirmed by the 's signature

Exclusion criteria

Exclusion Criteria:

  • The volunteer has a known to the study drug (topiramate) or to compounds chemically related
  • History or presence of hepatic or gastrointestinal illnesses, or other condition that interferes over the drug's absorption, distribution, excretion or metabolism
  • History of hepatic, renal, pulmonary, gastrointestinal, epileptic, hematologic or psychiatric illness; hypo or hypertension of any etiologic that needs pharmacologic treatment; has history or had myocardial infarction, angina and/or heart insufficiency
  • Non-recommended electrocardiographic findings, according to investigator criteria, for the study's participation
  • The results of the laboratory exams are out of the values considered as normal according to this protocol's rules, unless that they are considered as clinically irrelevant by the investigator
  • The volunteer is a smoker
  • The volunteer ingests more than 5 cups of coffee or tea a day
  • Has history of alcohol or drugs abuse
  • Use any regular drug within the 02 weeks that preceded the beginning of the treatment and the assessment date, or employed any drug that can interfere with the study within one week
  • The volunteer was hospitalized for any reason within 08 weeks of the beginning of this study's first period of treatment and the assessment date
  • Treatment within the 03 previous months of the study with any known drug that presents toxic potential for important organs
  • The volunteer participated in any experimental study or ingested any experimental drug within the 06 months that precede the beginning of this study and the assessment date
  • The volunteer donated or lost 450 mL or more of blood within the 03 months that preceded to the study initiation or donated more than 1500 mL within 12 months between the beginning of the study and the assessment date
  • Consume of inductive drugs and/or enzymatic inhibitors (CYP450 - hepatic), that are toxic for the organism or presenting long half-life's elimination within the 04 weeks that precede the study's initiation
  • Consume of alcohol in 48 hours antecedents to the admission to the study and along the study period
  • Consume of food or beverages containing grapefruit (grapefruit) within 24 hours preceding each study period
  • History of serious adverse reactions or hypersensitivity to any drug
  • The volunteer has any condition that obstructs his participation in the study according the investigator's judgement
Terms in these criteria, in plain language(3)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

05

Study design

Phase
Phase 1
Primary purpose
Other
Allocation
Randomized
Intervention model
Crossover assignment
Masking
None (open label)
Enrollment
26 participants (actual)

Study arms

  • Active comparator
    Test formulation

    Test product: Topiramate 100 mg coated tablets produced by Dr. Reddy's Laboratories Ltd. in Period 1, followed by 28 days washout period during which no medication was administered; followed by reference product: Topamax® 100 mg coated tablets in Period 2

    Drug: Topiramate coated tablet

  • Active comparator
    Reference formulation

    Topamax® 100 mg coated tablets marketed by Janssen-Cilag farmacêutica Ltda. in Period 1, followed by 28 days washout period during which no medication was administered; followed by test product: Topiramate 100 mg coated tablets produced by Dr. Reddy's Laboratories Ltd. in Period 2

    Drug: Topamax® coated tablet

Interventions

  • DrugTopiramate coated tablet

    Test formulation

  • DrugTopamax® coated tablet

    Reference formulation

06

What researchers measure

Primary outcomes

  1. Area under curve of plasma concentration of drug from time 0 (zero) from time t (last measurable concentration)

    The area under the plot of plasma concentration of drug against time (non-compartimental method), after drug administration, defined as the area under the curve (AUC). The AUC 0-t is calculated from time 0 (prior to administration of medication) to time t (the time of the last quantifiable concentration), by linear trapezoidal rule. The AUC is of particular use in estimating the bioavailability of drugs, by measuring the extent of absorption.

    Time frame: Collection points from time 0 to 192 hours evaluated in two periods

  2. Maximum observed concentration of drug through time (Cmax)

    Cmax is defined as the maximum or "peak" concentration of a drug observed after its administration. Cmax is one of the parameters of particular use in estimating the bioavailability of drugs, by measuring the total amount of drug absorbed. Measurement obtained directly of the plasma concentration curve of the drug (non-compartimental method). Occurring at Tmax.

    Time frame: Collection points from time 0 to 192 hours evaluated in two periods

  3. Area under curve of plasma concentration of drug from the time 0 (zero) extrapolated to infinity (AUC0-inf)

    Measurement obtained directly from the plasma concentration curve of drug against time (non-compartimental method). AUC0-inf is calculated from time 0 (prior to administration of medication) extrapolated to infinity, by formula AUC0-inf=AUClast +Clast/Kel, where Clast is the Last measurable concentration and Kel is the first order rate constant associated with the terminal portion of the curve.

    Time frame: Collection points from time 0 to 192 hours evaluated in two periods

  4. Time of maximum observed concentration (Tmax)

    Time when Cmax is obtained

    Time frame: Collection points from time 0 to 192 hours evaluated in two periods

  5. Terminal half-life - T1/2

    Calculated by formula: T1/2_Kel= Ln(2)/Kel.

    Time frame: Collection points from time 0 to 192 hours evaluated in two periods

  6. First order rate constant associated with the terminal portion of the curve (Kel)

    This parameter is estimated by the angular coefficient of the regression line, calculated by the minimum squares method, of the natural logarithm of the concentration versus time for the last four concentrations values (or at least three) above the quantification limit

    Time frame: Collection points from time 0 to 192 hours evaluated in two periods

07

Study locations

1 site
  • GSK Investigational Site
    Campinas, São Paulo, Brazil
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Ran from Jul 2011 to primary completion in Sep 2011, 1 month.

How these figures are worked out, and which studies are left out of them.

Registered
Sep 21, 2011
First posted
Sep 23, 2011
StartActual
Jul 22, 2011
Primary completionActual
Sep 11, 2011
CompletionActual
Sep 11, 2011
Last update
Jun 28, 2017
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jun 28, 2017, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT01439438
Lead sponsor
GlaxoSmithKline
Responsible party
Sponsor
First posted
Sep 23, 2011
Start date
Jul 22, 2011
Primary completion
Sep 11, 2011
Completion
Sep 11, 2011
Last update
Jun 28, 2017

Study contacts

GSK Clinical Trials
study director · GlaxoSmithKline

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Jun 2017. You cannot join it, but the record below documents what was studied.

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