Inulin Supplementation for Reducing Inflammation and Knee Pain in Older Adults With Osteoarthritis

NCT07189585 | Not Yet Recruiting Phase 2 DMC FDA Drug

• 3 other identifiers: 20000405231746261R61AT013472-01
• Study Type: interventional
• Target: 84
• Locations: 1 country
• Sites: 1

Brief Summary

This study will test whether inulin, a type of dietary fiber, can reduce inflammation in older adults with knee osteoarthritis. Inflammation in the body may contribute to both joint pain and the progression of osteoarthritis. Inulin is a prebiotic fiber that may improve gut health and reduce lipopolysaccharide (LPS), a marker of bacterial products in the blood that is linked to inflammation. In this trial, participants with knee osteoarthritis will be randomly assigned to receive either inulin or a placebo (maltodextrin) for 8 weeks. The study will measure changes in blood LPS levels, knee pain, and other markers of inflammation. The goal is to determine whether inulin supplementation can improve pain and reduce inflammation in people with knee osteoarthritis.

Conditions

Knee Osteoarthritis

Keywords

Inulin; Prebiotic; Lipopolysaccharide; Inflammation; Knee pain; Older adults

Outcome Measures

Primary Outcomes (1)

• Change in serum lipopolysaccharide (LPS) concentration from baseline to 8 weeks

  Serum LPS levels will be measured at baseline and at 8 weeks to evaluate the effect of inulin supplementation compared to placebo.

  Baseline and 8 weeks

Secondary Outcomes (2)

• Change in serum LPS concentration between 10 g and 15 g inulin groups

  Baseline and 8 weeks

• Change in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)

  Baseline and 8 weeks

Other Outcomes (4)

• Change in systemic inflammatory biomarkers

  Baseline and 8 weeks

• Change in synovial fluid LPS concentration

  Baseline and 8 weeks

• Change in knee pain

  Baseline and 8 weeks

Study Arms (3)

Placebo (Maltodextrin)

PLACEBO COMPARATOR

Participants receive maltodextrin powder in identical sachets. Dose is escalated over 2 weeks to match the dosing schedule of the inulin arms (5 g daily for 3 days, 10 g daily for 4 days, then 15 g daily). Sachets are mixed with food or beverage and taken once daily with the largest meal, for 8 weeks.

Drug: Maltodextrin (Placebo)

Inulin 10 g/day

EXPERIMENTAL

Participants receive inulin powder in identical sachets. Dose is escalated to 10 g daily (5 g daily for 3 days, then 10 g daily for 4 days). After Week 2, participants continue with one 15 g sachet containing a 2:1 blend of inulin and maltodextrin, providing a daily dose of 10 g inulin. Sachets are mixed with food or beverage and taken once daily with the largest meal, for 8 weeks.

Drug: inulin

Inulin 15 g/day

EXPERIMENTAL

Participants receive inulin powder in identical sachets. Dose is escalated to 15 g daily (5 g daily for 3 days, 10 g daily for 4 days, then 15 g daily). Sachets are mixed with food or beverage and taken once daily with the largest meal, for 8 weeks.

Drug: inulin

Interventions

inulin DRUG

Inulin is a fermentable prebiotic fiber derived from chicory root. For this study, inulin is packaged into single-dose sachets containing 5 g, 10 g, or 15 g of powder. Participants in the 10 g arm escalate from 5 g/day for 3 days to 10 g/day, then continue with sachets containing a 2:1 blend of inulin and maltodextrin to provide a daily 10 g inulin dose. Participants in the 15 g arm escalate from 5 g/day for 3 days, 10 g/day for 4 days, then 15 g/day for the remaining 8 weeks. Sachets are mixed with food or beverage and taken once daily with the largest meal.

Also known as: Orafti® Inulin, BENEO-Orafti

Inulin 10 g/day; Inulin 15 g/day

Maltodextrin (Placebo) DRUG

Maltodextrin is a carbohydrate powder widely used as a food additive. For this study, maltodextrin is used as the placebo comparator. It is packaged into single-dose sachets identical in appearance and taste to inulin sachets. Participants receive escalating doses (5 g/day for 3 days, 10 g/day for 4 days, then 15 g/day) for a total of 8 weeks. Sachets are mixed with food or beverage and taken once daily with the largest meal.

Also known as: Placebo

Placebo (Maltodextrin)

Eligibility Criteria

• Age: 40 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Provision of signed and dated informed consent form.
• Stated willingness to comply with all study procedures and availability for the duration of the study (8 weeks).
• Male or female, aged ≥ 40 years.
• Established patient in the VA Connecticut Healthcare System
• At least one knee with pain severity in the past week ≥ 4/10 on numerical rating scale (NRS)
• Self-reported knee pain on most days of the prior month.
• Diagnosed with knee osteoarthritis (Kellgren-Lawrence grade 2-4 on radiographic imaging within the past 2 years).
• Ability to take oral powder supplements and willingness to adhere to the inulin/placebo daily regimen.
• Agreement to adhere to lifestyle considerations (see Section 5.3) throughout study duration, including maintenance of current diet, physical activity, and avoidance of new dietary supplements or complementary therapies.
• English-speaking and able to provide informed consent.
• For females of reproductive potential: use of highly effective contraception for at least 1 month prior to screening and agreement to continue such method during study participation.

You may not qualify if:

• Current diagnosis of pre-diabetes (impaired glucose tolerance) or diabetes mellitus (Type 1 or Type 2).
• Use of antibiotics within the past 6 months.
• Current use of medications known to significantly impact the gut microbiome (e.g., proton pump inhibitors, disease-modifying antirheumatic drugs, GLP-1 receptor agonists).
• Use of anti-inflammatory dietary supplements (e.g., turmeric, omega-3 fatty acids) within the past 30 days.
• Participation in another interventional study or use of an investigational drug within the past 30 days.
• Current use of complementary or integrative therapies for knee OA including tai chi, acupuncture or yoga.
• Known allergy or intolerance to components of the study intervention, including inulin or maltodextrin.
• The presence of significant gastrointestinal disease that may interfere with the intervention or outcomes, such as inflammatory bowel disease or active peptic ulcer disease.
• Any medical, psychological, or behavioral condition that, in the opinion of the investigators, would place the participant at undue risk, interfere with study participation or adherence, or compromise data integrity.
• Current diagnosis of alcohol use disorder
• Pregnancy

Sponsors & Collaborators

• Yale University: lead
• VA Connecticut Healthcare System: collaborator
• National Center for Complementary and Integrative Health (NCCIH): collaborator

Study Sites (1)

VA Connecticut Healthcare System, West Haven Campus

West Haven, Connecticut, 06516, United States

Location

MeSH Terms

Conditions

Osteoarthritis, Knee; Inflammation

Interventions

Inulin; maltodextrin

Condition Hierarchy (Ancestors)

Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Starch; Glucans; Biopolymers; Polymers; Macromolecular Substances; Dietary Carbohydrates; Carbohydrates; Fructans; Polysaccharides

Study Officials

• Evelyn Hsieh, MD, PhD

  Yale University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Evelyn Hsieh, MD, PhD

CONTACT

(203) 785-7092; evelyn.hsieh@yale.edu

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Inulin and placebo are identical in appearance, taste, and packaging. Randomization is managed by the investigational pharmacy; study staff, investigators, and participants remain blinded.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Medicine

Model Details: Participants are randomized in a 1:1:1 ratio to placebo, 10 g/day inulin, or 15 g/day inulin for 8 weeks.

Study Record Dates

• First Submitted: September 16, 2025
• First Posted: September 24, 2025
• Study Start: April 1, 2026
• Primary Completion (Estimated): July 31, 2027
• Study Completion (Estimated): July 31, 2027
• Last Updated: September 24, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)