One shot, new knee? gene therapy trial aims to quiet arthritis pain

NCT ID NCT04119687

What the study statuses mean

This study's is highlighted.

Recruitment status, easiest to join first

Recruiting now
This trial is taking on new participants right now.
Not yet recruiting
Registered, but not yet taking participants.
By invitation only
Not open to general applications. Only people the study team invites can take part.
Paused
Paused for now. It may or may not start again.
Ongoing This study
Running, but no longer taking on new participants.
Completed
The trial has finished. Results may not be published yet.
Stopped early
Stopped early, before it reached the end. That can be for many reasons, including safety.
Cancelled
Cancelled before anyone took part.

Expanded access (not trials)

Expanded access
Not a trial. This treatment can be requested outside a study, case by case, for people who qualify.
Expanded access (paused)
Not a trial. The treatment can normally be requested outside a study, but is unavailable right now.
Expanded access (ended)
Not a trial. The treatment could once be requested outside a study, but no longer can.
Approved
The treatment has been approved, so it is available normally rather than through this programme.

When the status isn't known

Details not published
The full record has not been published yet, so there is little to show here.
Status unknown
This status has not been confirmed recently, so it may be out of date.

First seen Sep 17, 2026 · Last updated Sep 18, 2026 · Updated 1 time

Summary

Researchers are testing FX201, an experimental gene therapy, in adults aged 30 to 80 with painful knee osteoarthritis. Participants receive a single injection of FX201 into the affected knee. The study first checks safety at increasing doses, then gives more people the same dose to watch for side effects and see how the body handles the treatment.

What this could mean

Our plain-language read of the trial. This is informational only, not medical advice or a prediction.

Active substance
FX201, an experimental gene therapy injected into the knee that delivers instructions for a natural anti-inflammatory protein
What this could lead to
If it works, a single knee injection could one day ease osteoarthritis pain by helping the joint make its own anti-inflammatory protein.
What could go wrong
This is an early safety study with a small number of participants, so it may show the treatment is not safe or does not help. Gene therapy can trigger immune reactions or cause effects beyond the knee.

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 1

The first testing in people. Mainly checks safety and dose, usually in a small group.

Participants

72 people

The number who actually took part.

Started

Mar 2020

Expected to finish

Nov 2026

An estimate. End dates often move.

Lead sponsor

A company

The lead sponsor is a pharmaceutical, biotech, or medical-device company.

Who can take part

This study's own entry requirements. Only the study team can say for certain whether you qualify.

Ages

30 to 80 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

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Written consent to participate in the study * Male or female 30 to 80 years of age, inclusive, on the day of enrollment (Day 1) * Body mass index (BMI) ≤ 40 kilograms per meters squared (kg/m2) * Clinical diagnosis of OA of the knee on the American College of Rheumatology criteria (Altman, 1986) with radiologic evidence of OA (K-L Grade 2 or 3 for SAD Phase Cohort A and K-L Grade 2, 3 or 4 for SAD Phase Cohorts B and C and the Expansion Phase) at the index joint at the screening visit * Moderate pain in the index joint * Failed two or more types of conservative therapy for index knee osteoarthritis (e.g., structured exercise programs, topical or oral non-steroidal anti-inflammatory therapies); or failed one prior type of conservative therapy and at least one prior index knee IA treatment (corticosteroid or hyaluronic acid) * Sexually active females and males agree to use highly effective methods of contraception Exclusion Criteria: * Reactive arthritis, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, or arthritis associated with inflammatory bowel disease * History of or current infection in the index knee joint * Inability to undergo Magnetic Resonance Imaging (MRI) due to presence of surgical hardware or other foreign body in the index knee * Unstable index knee joint (e.g., torn anterior cruciate ligament, etc.) within 12 months of Screening * Any IA drug/biologic use within 6 months of Screening or 5 half-lives (whichever is longer) (e.g., IA corticosteroid, IA hyaluronic acid, platelet rich plasma injection, stem cells, prolotherapy and amniotic fluid injection, etc.) * Cold or radiofrequency nerve ablation of the index knee within 12 months of Screening * Arthroscopic or open surgery on the index knee within 12 months of Screening or planned/anticipated surgery on the index knee for the study period * Anticipated major surgery during the study period * Laboratory values that meet exclusion criteria * ECG abnormality at Screening or Baseline judged clinically significant * Use of immunomodulators, immunosuppressive, or chemotherapeutic agents within 5 years of Screening * Use of any other investigational drug, biologic or device within 3 months of Screening * Any systemic or local bacterial or viral infection requiring IV antibiotics or antivirals within 4 weeks of Screening or oral antibiotics or antivirals within 2 weeks of Screening * Known allergy or sensitivity to methylprednisolone * Any other clinically significant acute or chronic medical conditions (e.g., bleeding disorder) that, in the judgment of the Investigator, would preclude the use of an IA injection or that could compromise patient safety, limit the patient's ability to complete the study, and/or compromise the objectives of the study Note: Other protocol defined inclusion/exclusion criteria apply.

Get updates

Get notified about this study

Sign up to get updates when this study changes or when new studies for Osteoarthritis, knee are added.

Our safety recommendation!

By submitting, you agree to our Terms of use

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.

Contacts and locations

Locations

  • Altoona Center for Clinical Research

    Duncansville, Pennsylvania, 16635, United States

  • Arizona Research Center

    Phoenix, Arizona, 85053, United States

  • Center for Pharmaceutical Research

    Kansas City, Missouri, 64114, United States

  • Gulfcoast Research Institute, LLC

    Sarasota, Florida, 34232, United States

  • Metroplex Clinical Research Center

    Dallas, Texas, 75231, United States

  • University Orthopedics Center

    Altoona, Pennsylvania, 16602, United States

More trials for these conditions

Other studies related to the condition(s) this trial covers.