Zonisamide for Weight Reduction in Obese Adults

This study has been completed.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Information provided by (Responsible Party):
Duke University
ClinicalTrials.gov Identifier:
First received: January 10, 2006
Last updated: July 9, 2014
Last verified: February 2013
The primary aim of this study is to assess long-term weight loss efficacy of zonisamide relative to placebo in obese patients prescribed a dietary intervention.

Condition Intervention
Drug: Zonisamide

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Zonisamide for Weight Reduction in Obese Adults

Resource links provided by NLM:

Further study details as provided by Duke University:

Primary Outcome Measures:
  • Change in Body Weight [ Time Frame: 1 year ] [ Designated as safety issue: No ]
    The primary endpoint was weight loss at 1-year, Month-12 weight minus baseline weight, in kilograms.

Secondary Outcome Measures:
  • Proportions of Patients With 5% Weight Loss [ Time Frame: 1 year ] [ Designated as safety issue: No ]
    These were the proportions of patients losing 5% or more weight at 1-year relative to baseline. The measures were modeled with logistic regressions that included the three-level group proxy and a baseline weight covariate.

  • Proportions of Patients With 10% Weight Loss [ Time Frame: 1 year ] [ Designated as safety issue: No ]
    This outcomes measure followed the same principles at measurement of proportions of patients with 5% weight loss described elsewhere.

  • Waist Circumference [ Time Frame: 1 year ] [ Designated as safety issue: No ]
    Analyses was based on intent-to-treat ANCOVA. Difference scores from baseline to endpoint (Month-12) for each measure were regressed on the three-level proxy denoting group while controlling for the baseline value of the same measure. Contrasts were subsequently estimated in models, which had a significant overall treatment effect.

  • Inflammatory Markers [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  • Lipids [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  • Quality of Life [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  • Psychological Measures [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  • Blood Pressure [ Time Frame: 1 year ] [ Designated as safety issue: No ]

Enrollment: 225
Study Start Date: January 2006
Study Completion Date: September 2011
Primary Completion Date: September 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: A
Zonisamide 400 mg
Drug: Zonisamide
zonisamide 400 mg, 200 mg, or placebo
Experimental: B
Zonisamide 200 mg
Drug: Zonisamide
zonisamide 400 mg, 200 mg, or placebo
Placebo Comparator: C
matching placebo
Drug: Zonisamide
zonisamide 400 mg, 200 mg, or placebo

Detailed Description:
This RCT compares two doses of zonisamide and placebo for one year. A total of 225 subjects are randomly assigned to one of the three treatment interventions at Duke University Medical Centre. The primary outcome measure is change in body weight in kilograms. Secondary outcomes include changes in waist circumference, glycaemic and inflammatory markers, lipids, food craving, hunger and satiety, quality of life, blood pressure and heart rate.

Ages Eligible for Study:   18 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria: Age 18-65 years; BMI 30-50

Exclusion Criteria:

Secondary obesity; Significant cardiovascular disease; Stroke, seizure disorder or other significant neurological disease; Significant liver or gallbladder disease; Significant renal disease or history of kidney stones; HIV positive status; Diabetes mellitus; Untreated or unstable hypothyroidism Malignancy in the past 5 years; Concomitant medications that cause significant weight gain or weight loss; Concomitant use of prescription or OTC weight loss medications; Had bariatric surgery or planning surgery in the next 1 year; Weight change of more than 4 kg in the past 3 months; Suicidal subjects; Major depression in the past 6 months; History of psychosis, bipolar disorder, or severe personality disorders; Subjects taking antipsychotics or mood stabilisers; Alcohol or substance abuse in the past 6 months; Currently taking zonisamide or other antiepileptic drugs; History of hypersensitivity to zonisamide or sulfonamides; Pregnant or planning pregnancy in the next year, or breastfeeding; Severe physical disability; Current participation in a commercial weight loss program or planning to participate; Currently following low-carbohydrate, high protein, high fat diet; Use of investigational medications or devices (current or past 4 weeks)

  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00275834

United States, North Carolina
Duke University Medical Centre
Durham, North Carolina, United States, 27710
Sponsors and Collaborators
Duke University
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Principal Investigator: Kishore M Gadde, MD Duke University
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Duke University
ClinicalTrials.gov Identifier: NCT00275834     History of Changes
Other Study ID Numbers: Pro00005514  R01DK067352  1-RO1-DK067352 
Study First Received: January 10, 2006
Results First Received: December 10, 2012
Last Updated: July 9, 2014
Health Authority: United States: Food and Drug Administration
United States: Federal Government

Keywords provided by Duke University:
obesity treatment
weight loss
antiobesity drugs

Additional relevant MeSH terms:
Weight Loss
Body Weight
Body Weight Changes
Signs and Symptoms
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Protective Agents

ClinicalTrials.gov processed this record on May 26, 2016