Summary
Topiramate has reached the approved stage (maximum clinical phase 4) for at least one indication, so its use in Obesity would be drug repurposing rather than first-in-human development. This does not mean it is approved for Obesity. ClinicalTrials.gov lists 8 registered trials linking Topiramate to Obesity: 5 have completed; 3 are terminated, withdrawn, suspended or of unknown status. The most advanced is Phase 3 (NCT00563368). It plans or enrolled 756 participants. Registration activity spans 2001 to 2023. The literature layer holds 15 publications for this pair: 5 Cochrane reviews, 4 meta-analyses, 1 systematic review and 5 clinical trial publications. Publication years run from 2024 to 2026. Because at least one synthesis-level source exists (systematic review, meta-analysis or Cochrane review), this pair has been assessed beyond single studies, although the synthesis may concern a different indication.
The RepurpOS disease-intelligence file for Obesity ranks 368 candidate therapeutics from Open Targets, ChEMBL, DGIdb and PubMed; only a minority carry direct clinical evidence, and this page covers one of those. Spontaneous remission context recorded for the condition: Sustained weight loss of >5% without intervention: ~5-10% at 2 years; weight regain almost universal after behavioural intervention alone (95% return to within 5% of starting weight at 5 years on lifestyle alone).
Evidence table
| Evidence tier | A · Strong |
|---|---|
| Evidence score | 77.0 (trials 27.0, literature 30.0, tier 15, approved bonus 5.0) |
| Registered trials | 8 total: 0 recruiting, 0 active / not yet recruiting, 5 completed, 3 other |
| Linked publications | 15 (5 Cochrane reviews, 5 clinical trial publications, 4 meta-analyses, 1 systematic review) |
| Agent type | Drug (Small molecule) |
| Development stage (any indication) | Approved |
| Mechanism / class | inhibitor; inhibitor |
| Data sources | DGIdb |
| Linked via biomarker / target | CA4 |
How the evidence score is calculated
- Each registered trial scores by status (recruiting / active / enrolling 3, completed 2.5, not yet recruiting 2, unknown 1, terminated / withdrawn / suspended 0.5) plus a phase bonus (phase 3-4 +2, phase 2 +1, phase 1 +0.5). The trial component is capped at 30.
- Each literature item scores by design (Cochrane review 5, meta-analysis 4, systematic review 3, RCT 3, clinical trial publication 2, curated reference 1.5, other PubMed record 1). The literature component is capped at 30.
- The existing evidence tier adds 15 (A / Strong), 10 (B / Moderate), 5 (C / Preliminary) or 0 (D / Anecdotal).
- Agents approved for any indication (max clinical phase 4) add 5, because an approved agent has an established safety profile that lowers the barrier to repurposing trials.
- The score ranks what has been studied, not what works. It does not read effect sizes or directions of effect.
Registered clinical trials
| NCT ID | Title | Status | Phase | Enrolment |
|---|---|---|---|---|
| NCT02635386 | EQW, DAPA, EQW/DAPA, DAPA/MET ER and PHEN/TPM ER in Obese Women With PolycysticOvary Syndrome (PCOS) 2016 | completed | Phase 3 | 119 |
| NCT03374956 | Individualized Obesity Pharmacotherapy 2017 | completed | Phase 3 | 193 |
| NCT00563368 | A Study Comparing Multiple Doses of VI-0521 With Placebo and Their Single-agent Constituents for Treatment of Obesity in Adults 2007 | completed | Phase 3 | 756 |
| NCT00231621 | A Study on Efficacy and Safety of Topiramate in Treatment of Obese Subjects With Dyslipidemia 2001 | terminated | Phase 3 | 179 |
| NCT02810483 | Study of the Efficacy of Topiramate in Patients With Prader Willi Syndrome Over 8 Weeks 2012 | terminated | Phase 3 | 69 |
| NCT02659475 | Phentermine/Topiramate Extended Release in Binge Eating Disorder (BED) 2015 | completed | Phase 2 | 10 |
| NCT00806260 | A Study to Evaluate How VI-0521 Affect Psychomotor Performance in Healthy Overweight and Obese Subjects. 2008 | completed | Phase 2 | 80 |
| NCT05834062 | Phentermine/Topiramate as Preventive Pharmacotherapy for Obesity 2023 | withdrawn | Phase 2 | — |
Published literature
- Clinical trial publication Addition of Phentermine-Topiramate to a Digitally Enhanced Lifestyle Intervention: A Double-Blind Randomized Clinical TrialCampos A, Ghusn W, Cifuentes L et al. · Obesity (Silver Spring, Md.) · 2026 · PMID 41562388
- Cochrane review Pharmacotherapy for Children and Adolescents With Overweight or Obesity: A Systematic Review and Network Meta-Analysis of Randomized Controlled TrialsLuo L, Huang T, Yan Z et al. · Diabetes, obesity & metabolism · 2026 · PMID 42310900
- Cochrane review Benefits and Harms of Pharmacologic Treatments in Adults With Overweight or Obesity: A Living Systematic Review and Network Meta-analysis for the American College of PhysiciansDamen JAA, Idema DL, Vernooij RWM et al. · Annals of internal medicine · 2026 · PMID 42296503
- Cochrane review Pharmacological interventions for the treatment of obesity in children and adolescentsGerardi C, Allocati E, Prutsky G et al. · The Cochrane database of systematic reviews · 2026 · PMID 42125960
- Cochrane review Incretin-Based Therapies for the Treatment of Binge Eating-A Systematic ReviewWhite RT, Henriquez P, Innocent B et al. · Pharmacotherapy · 2026 · PMID 41947645
- Cochrane review Systematic review of influence of ethnicity on efficacy and safety of pharmacotherapy for childhood and adolescent obesityGupta S, Lal P, Gupta A et al. · Clinical and experimental pediatrics · 2026 · PMID 41582666
- Systematic review Mental health outcomes in obesity interventions with GLP-1 receptor agonists: is it similar to other obesity interventions? A narrative review with systematic evidence synthesisOsborne D, Abdelgadir E · International journal of obesity (2005) · 2026 · PMID 41491273
- Clinical trial publication Predictors of BMI reduction with phentermine/topiramate in adolescents with obesityBensignor MO, Freese RL, Rudser KD et al. · International journal of obesity (2005) · 2025 · PMID 40518455
- Clinical trial publication Genetic and physiological insights into satiation variability predict responses to obesity treatmentCifuentes L, Anazco D, O'Connor T et al. · Cell metabolism · 2025 · PMID 40482646
- Clinical trial publication Evaluation of the efficacy and safety of controlled-release phentermine/topiramate in adults with obesity in Korea: A randomized, double-blind, placebo-controlled, phase 4 trial (QUEEN's study)Hong S, Kim WJ, Kang ES et al. · Diabetes, obesity & metabolism · 2025 · PMID 39703109
- Meta-analysis [A meta-analysis of efficacy and safety of anti-obesity medications in the treatment of childhood obesity]Zhou XL, Wu W, Zhang L et al. · Zhonghua yi xue za zhi · 2025 · PMID 41218895
- Meta-analysis A systematic review and meta-analysis of the efficacy and safety of pharmacological treatments for obesity in adultsMcGowan B, Ciudin A, Baker JL et al. · Nature medicine · 2025 · PMID 41039116
- Meta-analysis Quantitative analysis of the efficacy characteristics and influencing factors of weight loss drugs in children and adolescentsWang Y, Chen J, He Y et al. · Diabetes, obesity & metabolism · 2025 · PMID 40642833
- Meta-analysis Efficacy and Safety of Pharmacological Interventions in Managing Cardiometabolic Risk Factors in Youth Living with Overweight and Obesity: A Systematic Review and Network Meta-AnalysisFaghfouri AH, Musazadeh V, Mokari-Yamchi A et al. · Obesity reviews : an official journal of the International Association for the Study of Obesity · 2025 · PMID 40437653
- Clinical trial publication Randomized study of the effects of empagliflozin and topiramate dual therapy on anthropometric and metabolic indices in non-diabetic individuals with overweight/obesity on a calorie-restricted dietAbiri B, Ramezani Ahmadi A, Hosseinpanah F et al. · Eating and weight disorders : EWD · 2024 · PMID 39361103
Mechanism and notes
Recorded mechanism or class: inhibitor; inhibitor.
OSMF's existing evidence tier for this pair is A (Strong), derived from the strength of the disease association recorded in DGIdb, in this case via the biomarker or target CA4. The tier describes how well the drug-disease link is documented, not how well the drug works.
Frequently asked questions
Is Topiramate approved for Obesity?
Topiramate has reached the approved stage (maximum clinical phase 4) for at least one indication, so its use in Obesity would be drug repurposing rather than first-in-human development. This does not mean it is approved for Obesity. Approval status for the specific indication should always be confirmed with the relevant regulator and prescribing information.
Is Topiramate in clinical trials for Obesity?
ClinicalTrials.gov lists 8 registered trials linking Topiramate to Obesity: 5 have completed; 3 are terminated, withdrawn, suspended or of unknown status. The most advanced is Phase 3 (NCT00563368). It plans or enrolled 756 participants. Registration activity spans 2001 to 2023.
What does the evidence show for Topiramate in Obesity?
Topiramate has both completed registered trials and synthesis-level publications linked to Obesity. That is the strongest profile in this database, but the summaries here do not extract effect sizes, so read the linked reviews for direction and magnitude of benefit. OSMF's existing evidence tier for this pair is A (Strong), derived from the strength of the disease association recorded in DGIdb, in this case via the biomarker or target CA4. The tier describes how well the drug-disease link is documented, not how well the drug works.
Cite this page
Data: ClinicalTrials.gov, PubMed, Open Targets, ChEMBL, DGIdb and the OSMF therapeutic agent database. Last updated 2026-07-05. Page built 2026-10-07.