Can pills reverse weight regain after bariatric surgery? new trial aims to find out.
NCT ID NCT05975580
First seen Jun 25, 2026 · Last updated Jun 27, 2026 · Updated 2 times
Summary
This study tests whether adding appetite-suppressant drugs (topiramate or phentermine) to lifestyle counseling can help people who have regained weight after bariatric surgery. About 120 adults who had sleeve gastrectomy or gastric bypass at least 18 months ago and regained at least 5% of their lowest post-surgery weight will participate. The trial compares the drugs against a placebo over 12 months to see which approach works best.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- Topiramate and phentermine (appetite suppressant drugs)
- What this could lead to
- If successful, this could provide a drug-based option to help people who regain weight after bariatric surgery lose it again, without additional surgery.
- What could go wrong
- This is a relatively small phase 4 trial, and the drugs may cause side effects like dizziness or dry mouth. Results may not apply to everyone who has had bariatric surgery.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Phase 4
Runs after approval, following long-term safety and how well the treatment works in everyday use.
- Participants
-
About 120 people
The number the study aims to enrol. It can still change while the study runs.
- Started
-
Aug 2023
- Expected to finish
-
Jan 2028
An estimate. End dates often move.
- Lead sponsor
-
Other sponsor
The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
18 to 70 years
- Sex
-
Anyone
- Healthy volunteers
-
Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
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
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Obesity are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
How to take part
Only the study team decides who joins. These are the ways to reach them.
-
The places running it
1 site. The list below names each one and where it is.
-
The official record
ClinicalTrials.gov lists the study team's own contact details, including names and phone numbers. We don't republish those.
-
A doctor treating you
A doctor who knows your case can contact a study site on your behalf, and can tell you whether this study is worth pursuing at all.
Contacts and locations
Locations
-
University of California Irvine Medical Center
RECRUITINGOrange, California, 92868, United States
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- Custom knee guides put to the test in obese patients
- A pill for obesity? early human trial puts MDR-001 to the test
- Can a weekly shot help people who still struggle with weight after bariatric surgery?
- Do GLP-1 Weight-Loss drugs change how teens eat and feel?
- Can electrical muscle stimulation boost exercise benefits after menopause?
- Can a cold cloth on the neck calm Post-Surgery nausea?