A Safety and Efficacy Study of Naltrexone SR/Bupropion SR in Obesity

This study has been completed.
Information provided by (Responsible Party):
Orexigen Therapeutics, Inc
ClinicalTrials.gov Identifier:
First received: November 30, 2007
Last updated: October 31, 2012
Last verified: October 2012

The purpose of this study is to determine if a combination of two drugs leads to more weight loss than each drug alone.

Condition Intervention Phase
Drug: naltrexone SR/bupropion SR
Drug: Placebo
Behavioral: Ancillary therapy
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: A Multicenter, Randomized, Double Blind, Placebo Controlled Study Comparing the Safety and Efficacy of Naltrexone Sustained Release (SR)/Bupropion Sustained Release (SR) and Placebo in Obese Subjects

Resource links provided by NLM:

Further study details as provided by Orexigen Therapeutics, Inc:

Primary Outcome Measures:
  • Co-primary outcome measures are the percentage of total body weight lost and the percentage of subjects who achieve a weight decrease of greater than or equal to 5% [ Time Frame: 28 weeks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Percent change weight; Proportion achieving a weight loss of ≥5% and ≥10%; Waist circumference; Fasting triglyceride,insulin, blood glucose and HDL cholesterol; HOMA-IR; IWQOL-Lite score; SF-36; IDS-SR score; hs-CRP; systolic and diastolic blood pressure [ Time Frame: 56 weeks ] [ Designated as safety issue: No ]

Enrollment: 1496
Study Start Date: November 2007
Study Completion Date: May 2009
Primary Completion Date: May 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: NB32
naltrexone SR/bupropion SR With ancillary therapy of diet instruction, advice on behavior modification and physical activity suggestions
Drug: naltrexone SR/bupropion SR
naltrexone SR 32 mg/bupropion SR 360 mg/day
Other Names:
  • NB32
  • Contrave
Behavioral: Ancillary therapy
Ancillary therapy of diet instruction, advice on behavior modification and physical activity suggestions
Placebo Comparator: Placebo
Placebo With ancillary therapy of diet instruction, advice on behavior modification and physical activity suggestions
Drug: Placebo Behavioral: Ancillary therapy
Ancillary therapy of diet instruction, advice on behavior modification and physical activity suggestions

Detailed Description:

Two Phase II clinical trials have demonstrated that the combination of naltrexone and bupropion SR is associated with greater weight loss than naltrexone alone, bupropion SR alone or placebo in subjects with uncomplicated obesity. The current study will investigate the safety and efficacy of the combination compared to placebo in obese subjects with uncomplicated obesity and in those with obesity and hypertension and/or dyslipidemia.


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

Inclusion Criteria:

  • Female and male subjects, 18 to 65 years of age
  • Have BMI of 30 to 45kg/m2 for subjects with uncomplicated obesity, and BMI of 27 to 45kg/m2 for subjects with obesity and controlled hypertension and/or dyslipidemia
  • Normotensive (systolic < or = to 140 mm Hg; diastolic < or = 90 mm Hg). Anti-hypertensive medications are allowed with the exception of alpha-adrenergic blockers, and clonidine. Medical regimen must be stable for at least 6 weeks prior to randomization
  • Medications for treatment of dyslipidemia are allowed as long as medical regimen has been stable for at least 6 weeks prior to randomization
  • Free of any opioid medication for at least 7 days prior to randomization
  • No clinically significant abnormality of serum albumin, blood urea nitrogen, creatinine, bilirubin, sodium, potassium, chloride, calcium or phosphorus
  • ALT and AST within 2.5 x upper limit of normal (ULN)
  • No clinically significant abnormality of hematocrit, white blood cell count, white cell differential, or platelets
  • Fasting glucose < 126 mg/dL on no hypoglycemic agents, fasting triglycerides < 400 mg/dL.
  • TSH within normal limits or normal T3, if TSH is below normal limits
  • Negative serum pregnancy test in women of child bearing potential
  • Negative urine drug screen
  • If woman of child bearing potential, must be non-lactating and agree to use effective contraception throughout the study period and 30 days after discontinuation of study drug
  • Able to speak and read English

Exclusion Criteria:

  • Serious medical condition
  • History of malignancy within the previous 5 years, with exception of non-melanoma skin cancer or surgically cured cervical cancer
  • A lifetime history a serious psychiatric illness
  • Current serious psychiatric illness
  • In need of medications for the treatment of a psychiatric disorder (with the exception of short-term insomnia) within the previous 6 months prior to randomization
  • History of drug or alcohol abuse or dependence (with the exception of nicotine dependence) within 1 year prior to study participation.
  • Type I or Type II diabetes mellitus
  • On prohibited concomitant medications
  • History of surgical or device (e.g. gastric banding) intervention for obesity
  • History of seizures of any etiology, or of predisposition to seizures
  • History of treatment with bupropion, or naltrexone within the preceding 12 months
  • History of hypersensitivity or intolerance to bupropion or naltrexone
  • Use of nicotine replacement products (nicotine gum, patch etc) during study participation is not allowed.
  • Loss or gain of more than 4.0 kilograms within 3 months prior to randomization
  • Pregnant or breast-feeding women or planning to become pregnant during the study period or within 30 days of discontinuing study drug
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00567255

  Show 36 Study Locations
Sponsors and Collaborators
Orexigen Therapeutics, Inc
Principal Investigator: Frank Greenway, MD Pennington Medical Research Center, Louisiana State University
  More Information

No publications provided

Responsible Party: Orexigen Therapeutics, Inc
ClinicalTrials.gov Identifier: NCT00567255     History of Changes
Other Study ID Numbers: NB-303
Study First Received: November 30, 2007
Last Updated: October 31, 2012
Health Authority: United States: Food and Drug Administration

Keywords provided by Orexigen Therapeutics, Inc:

Additional relevant MeSH terms:
Body Weight
Nutrition Disorders
Signs and Symptoms
Antidepressive Agents
Antidepressive Agents, Second-Generation
Central Nervous System Agents
Dopamine Agents
Dopamine Uptake Inhibitors
Molecular Mechanisms of Pharmacological Action
Narcotic Antagonists
Neurotransmitter Agents
Neurotransmitter Uptake Inhibitors
Peripheral Nervous System Agents
Pharmacologic Actions
Physiological Effects of Drugs
Psychotropic Drugs
Sensory System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on October 20, 2014