RESTOREGI Study: Regenerative Endoscopic Stromal Therapy: Outcomes and Risk Factor Evaluation in GI Fistulas (RESTORE-GI)

PROSPECTIVE RISK FACTOR ANALYSIS OF CLINICAL OUTCOMES FOLLOWING ENDOSCOPIC tSVF-em THERAPY FOR BENIGN GASTROINTESTINAL FISTULAS - RESTOREGI Study

RESTOREGI Study Benign gastrointestinal fistulas are abnormal communications between the gastrointestinal tract and adjacent organs or the skin. Chronic fistulas are often difficult to treat because of persistent inflammation, fibrosis, impaired vascularity, and defective tissue regeneration. Endoscopic regenerative therapy using mechanically processed autologous total stromal vascular fraction-enriched microfragmented adipose tissue (tSVF-EM) has emerged as a novel therapeutic approach that may promote tissue repair through angiogenesis, immunomodulation, and regenerative signaling.

Although early clinical experience suggests promising healing outcomes, factors predicting successful fistula closure remain poorly understood. The RESTOREGI study is a prospective, single-center observational cohort study designed to identify patient-related, fistula-related, and procedural factors associated with successful healing following endoscopic tSVF-EM therapy in benign gastrointestinal fistulas. The study will also evaluate treatment safety, time to healing, recurrence rates, and the impact of procedural variables on outcomes.

Study Overview

• Status: Not yet recruiting
• Conditions: Fistula; Regenerative Medicine; Stromal Vascular Fraction
• Intervention / Treatment: Procedure: Endoscopic tSVF-EM Therapy

Detailed Description

Benign gastrointestinal fistulas are abnormal communications between the gastrointestinal tract and adjacent organs or the skin that can result in significant morbidity, prolonged hospitalization, impaired quality of life, and repeated therapeutic interventions. Chronic fistulas are characterized by persistent inflammation, fibrosis, impaired perfusion, and defective tissue regeneration, all of which may contribute to failure of conventional closure techniques and recurrent disease.

Endoscopic regenerative therapy using autologous total stromal vascular fraction-enriched microfragmented adipose tissue (tSVF-EM) has emerged as a novel therapeutic approach for the management of complex gastrointestinal defects. Following adipose tissue harvest and mechanical processing, tSVF-EM contains a heterogeneous population of stromal and regenerative cells, extracellular matrix components, and bioactive factors that may promote angiogenesis, immunomodulation, tissue remodeling, and wound healing. Endoscopic delivery of this material directly into the fistula margins aims to create a biologically favorable environment for durable tissue repair.

Early clinical experience with regenerative endoscopic therapies has demonstrated technical feasibility and encouraging healing outcomes in selected patients with benign gastrointestinal fistulas. However, considerable variability in treatment response exists, and factors associated with successful healing remain poorly understood. Improved understanding of patient-related, fistula-related, and procedural determinants of treatment success may facilitate better patient selection, optimize procedural planning, guide the use of adjunctive therapies, and improve overall clinical outcomes.

The RESTOREGI study is a prospective, single-center, real-world cohort study designed to evaluate clinical outcomes following endoscopic tSVF-EM therapy in patients with benign gastrointestinal fistulas. Standardized data will be collected regarding patient characteristics, fistula anatomy and etiology, inflammatory and nutritional status, and procedural factors associated with regenerative endotherapy. The study is intended as an exploratory, hypothesis-generating investigation to identify clinically meaningful factors associated with fistula healing and to establish prospective safety and effectiveness data in this emerging field of regenerative endoscopy.

Findings from this study are expected to provide foundational evidence for future multicenter studies and contribute to the development of evidence-based patient selection and treatment strategies for regenerative management of benign gastrointestinal fistulas.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Goutham K Katukuri, MBBS, MD, DM; Phone Number: +919902305703; Email: goutham.mge@gmail.com
• Study Contact Backup: Name: Rajendra Patel, MBBS, MD, DM; Phone Number: +918152049069; Email: doc.rajendrapatel@gmail.com

Study Locations

• India
  • Telangana
    • Hyderabad, Telangana, India, 500075
      • AIG Hospitals
      • Contact: Nageshwar R Duvvur, MBBS, MD, DM; Phone Number: +914042444222; Email: aigindia@yahoo.co.in
      • Principal Investigator: Goutham R Katukuri, MBBS, MD, DM

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥18 years
• Confirmed benign gastrointestinal fistula involving the luminal gastrointestinal tract
• Fistula accessible for endoscopic evaluation and treatment
• Planned treatment with endoscopic tSVF-EM therapy, with or without adjunctive endoscopic therapies (argon plasma coagulation [APC], tract abrasion/curettage, clips, over-the-scope clips [OTSC], endoscopic suturing, or stent placement)
• Ability and willingness to provide written informed consent
• Willingness to comply with scheduled follow-up visits and study assessments

Exclusion Criteria:

• Perianal fistulas of any aetiology
• Inflammatory bowel disease-associated fistulas, including fistulas related to Crohn's disease or ulcerative colitis
• Malignancy-related fistulas
• Fistulas requiring primary oncologic surgical management
• Uncontrolled sepsis or undrained abscess at baseline (patients may become eligible following adequate drainage and clinical stabilisation)
• Contraindication to adipose tissue harvest, sedation, anaesthesia, or therapeutic endoscopy
• Pregnancy or lactation
• Severe coagulopathy not correctable prior to intervention
• Inability to provide informed consent
• Anticipated inability to complete study follow-up
• Participation in another interventional study that may influence fistula healing outcomes

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Endoscopic tSVF-EM Therapy for Benign Gastrointestinal Fistulas; Participants with benign gastrointestinal fistulas will undergo endoscopic regenerative therapy using autologous total stromal vascular fraction-enriched microfragmented adipose tissue (tSVF-EM). Adjunctive endoscopic therapies including argon plasma coagulation, tract abrasion, clipping, over-the-scope clip placement, endoscopic suturing, or stenting may be performed at the discretion of the treating physician. Repeat tSVF-EM sessions are permitted according to clinical response.

Procedure: Endoscopic tSVF-EM Therapy; Autologous adipose tissue will be harvested using standard liposuction techniques and mechanically processed to obtain total stromal vascular fraction-enriched microfragmented adipose tissue (tSVF-EM). The processed tissue will be injected endoscopically into the margins and/or tract of benign gastrointestinal fistulas according to institutional regenerative endoscopy protocols. Adjunctive endoscopic therapies, including argon plasma coagulation (APC), fistula tract abrasion or curettage, clips, over-the-scope clips (OTSC), endoscopic suturing, or stent placement, may be performed at the discretion of the treating physician. Repeat tSVF-EM treatment sessions may be undertaken based on clinical response and persistence of the fistula.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite Fistula Healing at 6 Months	Composite fistula healing is defined as the simultaneous achievement of: Clinical resolution of the fistula, characterized by the absence of fistula output, drainage, or symptoms attributable to the fistula; and Objective confirmation of closure demonstrated by either: Endoscopic evidence of complete closure of the fistula opening, or Radiological evidence of absence of contrast extravasation or fistulous communication on appropriate imaging studies. Participants meeting both criteria will be classified as having achieved successful fistula healing.	6 months following the first tSVF-EM treatment session

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of tSVF-EM Treatment Sessions Required for Healing	Total number of endoscopic tSVF-EM treatment sessions required to achieve composite fistula healing.	Up to 12 months after first treatment session
Time to Fistula Healing	Time from the first tSVF-EM treatment session to achievement of composite fistula healing, defined as clinical resolution of fistula output and objective confirmation of closure by endoscopy or imaging.	Up to 12 months after first treatment session
Fistula Recurrence Rate	Proportion of participants who develop recurrence of a previously healed fistula, defined as reappearance of clinical drainage and/or objective evidence of fistula reopening after documented healing.	12 months after first treatment session
Treatment-Related Adverse Events	Incidence, type, severity, and outcome of adverse events related to adipose tissue harvest, endoscopic intervention, sedation/anesthesia, and delayed infectious complications. Adverse events will be graded according to the ASGE Lexicon classification system.	From treatment initiation through 12 months of follow-up
Overall Clinical Healing Rate	Proportion of treated fistulas achieving clinical healing during the study period.	12 months after first treatment session
Need for Additional Endoscopic or Surgical Intervention	Proportion of participants requiring alternative endoscopic therapies, radiologic interventions, or surgery because of persistent or recurrent fistula despite tSVF-EM therapy.	12 months after first treatment session

Collaborators and Investigators

• Sponsor: Asian Institute of Gastroenterology, India
• Investigators: Principal Investigator: Goutham R Katukuri, MBBS, MD, DM, AIG Hospitals

Study record dates

Study Major Dates

• Study Start (Estimated): June 15, 2026
• Primary Completion (Estimated): August 31, 2027
• Study Completion (Estimated): August 31, 2027

Study Registration Dates

• First Submitted: June 5, 2026
• First Submitted That Met QC Criteria: June 18, 2026
• First Posted (Actual): June 22, 2026

Study Record Updates

• Last Update Posted (Actual): June 22, 2026
• Last Update Submitted That Met QC Criteria: June 18, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Stromal vascular fraction; Mesenchymal stromal cells; Gastrointestinal fistula; Endoscopic fistula closure; Regenerative endoscopy
• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Digestive System Diseases; Pathological Conditions, Signs and Symptoms; Fistula; Digestive System Fistula
• Other Study ID Numbers: tSVF-EM; Version:02

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: ndividual participant-level data collected during this study will not be made publicly available. De-identified aggregate study results may be published in scientific journals and presented at scientific meetings.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No