Prevention of Type 2 Diabetes in Subjects With Prediabetes and Metabolic Syndrome Treated With Phentermine and Topiramate Extended-Release

  1. Wesley W. Day, PhD7
  1. 1Department of Nutrition Sciences, University of Alabama at Birmingham and the Birmingham VA Medical Center, Birmingham, Alabama, USA;
  2. 2Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA;
  3. 3University of California San Diego School of Medicine and the San Diego VA Medical Center, San Diego, California, USA;
  4. 4Monteagle Medical Center, San Francisco, California, USA;
  5. 5Medical University of Graz, Graz, Austria;
  6. 6Medpace, Cincinnati, Ohio, USA;
  7. 7VIVUS, Inc., Mountain View, California, USA
  1. Corresponding Author: W. Timothy Garvey, Email: garveyt{at}


Objective To evaluate over 108 weeks the effect of phentermine and topiramate extended-release (PHEN/TPM ER) treatment on progression to type 2 diabetes and/or cardiometabolic disease in subjects with Prediabetes and/or Metabolic Syndrome (MetS) at baseline.

Research Design and Methods Subanalysis of a Phase 3, randomized, placebo-controlled, double-blind study of overweight/obese subjects (BMI ≥27 to ≤45 kg/m2) with ≥2 comorbidities. Subjects were randomized to placebo, PHEN 7.5mg/TPM ER 46mg (7.5/46), or PHEN 15mg/TPM ER 92mg (15/92) plus lifestyle modifications for 108 weeks. Percent weight loss in the intent-to-treat population using multiple imputation (ITT-MI), annualized incidence rate of progression to type 2 diabetes, and changes in glycemia, lipid parameters, blood pressure, and waist circumference were evaluated.

Results At baseline, 475 subjects met the criteria for Prediabetes and/or MetS. After 108 weeks, subjects with Prediabetes and/or MetS in the placebo, 7.5/46, and 15/92 groups experienced mean percent weight loss of 2.5%, 10.9%, and 12.1%, respectively (ITT-MI; P < 0.0001 vs placebo associated with reductions of 70.5% and 78.7% in the annualized incidence rate of type 2 diabetes for those receiving 7.5/46 and 15/92, respectively (ITT; P < 0.05),versus placebo, which was related to degree of weight lost and was accompanied by significant improvements in cardiometabolic parameters. PHEN/TPM ER was well tolerated by this subgroup over 2 years.

Conclusions PHEN/TPM ER plus lifestyle modification produced significant weight loss and markedly reduced progression to type 2 diabetes in overweight/obese patients with Prediabetes and/or MetS, accompanied by improvements in multiple cardiometabolic disease risk factors.

  • Received June 27, 2013.
  • Accepted September 27, 2013.

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