Pharmacotherapy in Conjunction With Lifestyle Counseling for Management of Weight Regain After Bariatric Surgery

Inclusion Criteria: 1. Male and female subjects aged 18-70 years 2. Had sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) at least 18 months ago 3. Weight regain of ≥5% relative to post-surgery nadir weight 4. Body mass index (BMI) ≥30 kg/m2 or ≥27 kg/m2 with weight-related comorbidities 5. Women of childbearing potential must be using appropriate contraception to avoid pregnancy throughout the study, and must have a negative pregnancy test at study entry 6. Must be able to provide written informed consent Exclusion Criteria: 1. Type 1 diabetes 2. Insulin-dependent type 2 diabetes 3. Fasting plasma glucose (FPG) ≥240 mg/dL 4. Uncontrolled hypertension defined as systolic blood pressure (SBP) ≥150 mm Hg and/or diastolic blood pressure (DBP) ≥100 mm Hg on the average of three seated measurements after being at rest for at least 5 minutes 5. History of significant (as determined by the investigator) and unstable cardiovascular disease including coronary artery disease, arrhythmias, severe congestive heart failure, or stroke 6. Use of monoamine oxidase inhibitors, current or within 2 weeks 7. Hyperthyroidism or other significant thyroid disease 8. Angle-closure glaucoma 9. Agitated states 10. History of drug abuse within the past year 11. Known hypersensitivity or idiosyncrasy to sympathomimetic amines 12. Severe hepatic disease (non-alcoholic fatty liver disease or non-alcoholic steatohepatitis without portal hypertension or cirrhosis is acceptable) 13. End-stage renal disease 14. History of nephrolithiasis 15. Serum triglycerides ≥500 mg/dL 16. Cancer, not in remission, within the past 2 years except for adequately treated basal cell, squamous cell skin cancer, or in-situ cervical cancer 17. History of psychosis or bipolar disorder 18. Suicidal ideation or unstable/untreated major depressive disorder within the past year 19. Use of antidepressant medication that has not been at stable dose for at least 3 months 20. Hospital Anxiety and Depression Scale (HADS) score of ≥11 for depression or anxiety items 21. Binge Eating Scale (BES) score of ≥27 22. Alcohol use disorder within the past year 23. Epilepsy 24. Currently taking phentermine or topiramate or the combination, or products containing these drugs 25. Currently taking stimulants (e.g., Attention Deficit Hyperactivity Disorder medications) 26. Current use of prescription or over-the-counter weight loss drugs or supplements 27. Taking prescription or over-the-counter drugs or products, which in the opinion of the PI, could be associated with significant effects on body weight 28. Planning additional bariatric surgery procedures in the next 13 months 29. History of revisional bariatric surgery (revisional surgery after adjustable gastric banding is acceptable) 30. Currently participating in another weight loss program or have plans to participate in the next 13 months 31. Smoking cessation within the previous 3 months or plans to quit smoking in the next 13 months 32. Pregnant or breastfeeding or planning pregnancy in the coming 13 months 33. History of, or any existing condition that, in the opinion of the Principal Investigator, would interfere with the study outcomes or place the subject at unacceptable risk by participating in the study