DB-3Q extracellular vesicle therapy for perianal Crohn's fistulas

A Phase 2a Study of Allogeneic Bone Marrow Mesenchymal Stem Cell Derived Extracellular Vesicle Isolate Product (DB-3Q) in Patients With Perianal Fistulizing Crohn's Disease

Phase 2 Interventional Direct Biologics, LLC · NCT06918808

This Phase 2 test uses DB-3Q, a treatment made from bone marrow mesenchymal stem cell-derived extracellular vesicles, to see if it can heal active perianal fistulas in adults with Crohn's disease who haven't responded to other treatments.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment36 (estimated)
Ages18 Years to 75 Years
SexAll
SponsorDirect Biologics, LLC Industry-sponsored
Drugs / interventionsadalimumab, certolizumab, golimumab, guselkumab, infliximab, risankizumab, ustekinumab, vedolizumab, tofacitinib, upadacitinib, methotrexate
Locations3 sites (Aurora, Colorado and 2 other locations)
Trial IDNCT06918808 on ClinicalTrials.gov

What this trial studies

This is a double-blind, randomized, placebo-controlled, sequential-cohort, ascending-dose Phase 2 trial comparing DB-3Q to placebo in adults with active draining perianal fistulas due to Crohn's disease. Participants will be assigned to increasing dose cohorts and receive either DB-3Q or placebo under blinded conditions to monitor safety and signs of fistula healing. Eligible patients must have had Crohn's disease for at least six months, draining fistulas with two or fewer openings, prior failure of medical therapy or surgery, and stable background Crohn's medications before dosing. The trial is being conducted at multiple U.S. sites with scheduled follow-up visits to document adverse events and fistula outcomes.

Who should consider this trial

Good fit: Adults 18–75 years old with Crohn's disease for at least six months who have actively draining single- or multi-tract perianal fistulas with two or fewer openings and who have failed prior medical and/or surgical treatments are the intended candidates.

Not a fit: Patients with more than two external openings, non-draining or completely healed fistulas, recent changes in Crohn's medications, or other contraindications are unlikely to qualify and may not receive benefit from this protocol.

Why it matters

Potential benefit: If successful, DB-3Q could promote closure of perianal fistulas and reduce the need for additional surgery or prolonged high-risk medical therapy.

How similar studies have performed: Local injections of mesenchymal stromal cell therapies have shown benefit for refractory perianal Crohn's fistulas in prior trials, but use of bone marrow MSC-derived extracellular vesicles (EVs) is a newer, less-tested approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Written informed consent from participant
2. Men and women 18-75 years of age with a diagnosis of Crohn's Disease for at least six months duration prior to Day 1
3. Single and/or multi-tract perianal fistula(s) with 2 or fewer openings, that are actively draining
4. Failed at least one medical therapy within the last year including, but not limited to, antibiotics, immunomodulators (6-MP, methotrexate, azathioprine), monoclonal antibodies (adalimumab, certolizumab, golimumab, guselkumab, infliximab, risankizumab, ustekinumab, vedolizumab), or small molecule inhibitors (tofacitinib, upadacitinib)
5. Previous failed surgical intervention, including seton placement at least two weeks prior to screening, or are not candidates for surgical intervention or are not willing to undergo surgical intervention for the management of their fistula
6. Medical therapy for CD stable for at least 2 months prior to Day 1 (Changes in dosing or dosing intervals related to serum drug levels are not permitted)

Exclusion Criteria:

1. Lack of informed consent
2. Pregnant woman, woman of childbearing potential without a documented negative urine or serum pregnancy test, or woman who is breast feeding
3. A participant who is unwilling to use medically acceptable contraception methods during participation in study
4. Active perianal abscess or infection at screening or Day 1
5. Clinically significant medical conditions within six months before Day 1 that would, in the opinion of the Investigator, compromise the safety of the participant
6. Confirmed HIV, Hepatitis B, or Hepatitis C infections
7. History of cancer including melanoma (with the exception of localized non-melanoma skin cancers) within one year of screening
8. History of colorectal cancer within 2 years of screening
9. Use of investigational therapy or treatment within 30 days prior to Day 1

Where this trial is running

Aurora, Colorado and 2 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Perianal Fistula Due to Crohn's Disease
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.