AzTrials
AzTrials

Osteoarthritis (OA) of the KneePhase 2NCT06865079

53-Week Study Evaluating the Safety and Efficacy of Intra-articular Injections of TPX-100 With Mild to Severe Tibio-Femoral Osteoarthritis of the Knee

A Phase 2 study testing TPX-100 200mg, Once weekly for 4 weeks and PBS in people with Osteoarthritis (OA) of the Knee, run by OrthoTrophix, Inc at 33 sites in United States.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record
Search all trials

Trial summary

53-Week Study Evaluating the Safety and Efficacy of Intra-articular (IA) Injections of TPX-100 vs Placebo in Subjects with Mild to Severe Tibio-Femoral Osteoarthritis of the Knee Read more about this study

Who is it for?
Ages 50 to 80 years
Conditions the study is for
Osteoarthritis (OA) of the Knee
What is being tested?
TPX-100 200mg, Once weekly for 4 weeks and PBS
Type of treatment
Injection or infusion
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
270 participants
Where
33 sitesUnited States
Study dates
9 May 2025to 15 Apr 2027
Phase
Phase 2
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 50 to 80 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Volunteers will be included in the study only if they satisfy all the following criteria:
  • Able to read, understand, sign, and date the subject informed consent.
  • Have given written informed consent before any study-related activities are carried out and are able to understand the nature and purpose of the trial, including possible risks and adverse effects.
  • Adult males and females, 50 to 80 years of age (inclusive) at Screening.
  • Body weight less than 136 kgs (300 lbs) at Screening.
  • Except for OA, subject is medically healthy (in the opinion of the PI), as determined by prestudy medical history, and without clinically significant abnormalities including:
Show all 25Show fewer
  • Clinically relevant findings on physical examination that would preclude trial compliance.
  • Heart rate <40 BPM or >100 BPM after 5 minutes rest in supine or semi-supine position.
  • Body temperature <95.9°F or >99.8°F. Note: The above assessments may be repeated, if abnormal values are recorded in the first instance, at the discretion of the Investigator (or delegate).
  • Available X-Ray of target knee obtained within 12 months prior to Screening with radiographic evidence of osteoarthritis in the medial and/or lateral tibio-femoral compartment; KL grading is not required.
  • Clinical diagnosis of knee OA with at least 2 of the 4 following signs/symptoms in the target knee, and in the absence of palpable warmth suggesting synovitis or infection:
  • Crepitus on knee extension
  • Bony tenderness
  • Bony enlargement
  • Morning stiffness in target knee <30 minutes
  • Stability of Cruciate and collateral ligaments as defined by clinical examination (e.g. tests such as Lachman, pivot shift, posterior drawer, posterior sag, valgus and Varus stress).
  • Results of the KOOS Knee Survey Screening Questionnaire performed at Screening for the target knee that indicate either: moderate or greater difficulty in at least 5 of 17 questions (A1-17) in the "Function, daily living" subsection; or a total score of at least 20/68 in that subsection.
  • Results of the KOOS Knee Survey Screening Questionnaire performed at Screening that indicate moderate or greater pain on question P6 "pain going up or down stairs" in the target knee.
  • Willing to use only acetaminophen (Tylenol® or equivalent), hydrocodone, orhydrocodone/acetaminophen (e.g., Norco® or equivalent) for breakthrough pain during the4-week injection period. The maximum dose of acetaminophen from all sources must not exceed 4000 mg/day.
  • Willing NOT to use non-steroidal anti-inflammatory drugs such as aspirin, ibuprofen (Motrin® or equivalent), or naproxen (Aleve® or equivalent) during the 4-week injection period.
  • Willing NOT to use approved or investigational IA products for knee OA for the duration of participation in the study.
  • If using GLP-1 medications such as Wegovy® or similar, must be on a stable dose for at least 2 months prior to Screening.
  • Female subjects of childbearing potential who are sexually active (non-abstinent) must agree to and comply with using 2 highly effective methods of birth control (oral contraceptive implant, injectable or indwelling intrauterine device, condom with spermicide or sexual abstinence) while participating in the study. Male participants must agree to use a barrier contraception method to prevent pregnancy, and agree not to donate sperm from the time of the first injection through the end of the study.
  • Willing and able to comply with all study assessments and adhere to the protocol schedule and restrictions.
  • MRI Screening: Tibio-femoral osteoarthritis with MRI based femoral B-score at Screening of 0.5 or greater in at least one knee as determined by central analysis.

Who cannot join

  • Subjects are excluded from the study if any of the following criteria are met:
  • Contraindication to MRI.
  • Demonstrated clinically significant (required intervention, e.g., emergency room visit, epinephrine administration) allergic reactions (e.g., food, drug, or atopic reactions, asthmatic episodes) which, in the opinion of the Investigator, would interfere with the volunteer's ability to participate in the trial.
  • Prior surgery in the target knee, excluding procedures for debridement only (no previous micro-fracture procedure).
  • Knee joint replacement or any other knee surgery planned in either knee while participating in the study.
  • Moderate or severe pain in the contralateral (non-target) knee.
Show all 32Show fewer
  • History of fibromyalgia, rheumatoid arthritis (RA), psoriatic arthritis, or any other autoimmune or infectious cause for arthritis; or referred knee pain from hip or spinal disease.
  • Knee effusion >2+ on the following clinical scale:
  • Zero = No wave produced on down stroke
  • Trace = Small wave on medial side with down stroke
  • 1+ = Larger bulge on medial side with down stroke
  • 2+ = Effusion spontaneously returned to medial side after upstroke (no down stroke necessary)
  • 3+ = So much fluid that it was not possible to move the effusion out of the medial aspect of the knee
  • Last viscosupplementation (e.g., Synvisc® or similar hyaluronic acid product) injected into either knee < 3 months before Screening.
  • Last IA injection of corticosteroids < 2 months before Screening.
  • Current (within previous month before Screening) of use of any systemic steroids (except inhaled corticosteroids for allergy or respiratory problems).
  • Known hypersensitivity to any of the study drug ingredients.
  • Known hypersensitivity to acetaminophen or hydrocodone.
  • History of arthroscopy in the target knee in the 3 months before Screening.
  • History of septic arthritis, gout, or pseudo-gout in either knee in the year before Screening.
  • Clinical signs in the opinion of the Investigator of acute meniscal tear (e.g. locking or acute mechanical signs or symptoms consistent with meniscal tear) in either knee.
  • Skin lesion, rash, infection, or hypersensitivity in the target knee at or near the injection site at Screening.
  • Bleeding problems, platelet or coagulation deficiency that, in the option of the Investigator, contraindicates IA injection.
  • Active systemic infection at Screening or immediately pre-dose on any IA injection day, including chronic viral infection.
  • Current treatment or treatment within 2 years prior to Screening for any malignancy except basal cell or squamous cell carcinoma of the skin, prostate or cervical cancer in situ, unless with specific written permission provided by the Sponsor's Medical Monitor.
  • Women of childbearing potential who are pregnant, nursing, or planning to become pregnant, and women or men who do not agree to remain on an acceptable method of birth control throughout the entire study period.
  • Participation in other clinical OA drug studies within 1 year prior to Screening except epidemiologic studies involving no drug treatment.
  • Any participation in other clinical OA stem cell or gene therapy studies.
  • Currently taking paclitaxel (mitotic inhibitor), natalizumab (anti-integrin monoclonal antibody), or any other anti-integrin treatment.
  • Routine consumption of more than 3 alcoholic drinks a day (definition of 1 alcoholic drink:
  • 12-ounces of beer, 8-ounces of malt liquor, 5-ounces of wine, 1.5- ounces or a "shot" of 80-proof distilled spirits or liquor such as gin, rum, vodka, or whiskey).
  • History of substance abuse in the opinion of the Investigator within the two years prior to Screening.

Trial locations and contacts

33 sites in 1 country.

33 sites in 1 country

United States33 sites

  • Albuquerque Clinical Trials

    Albuquerque, New Mexico, 87102

  • University Orthopedics Center

    Altoona, Pennsylvania, 16602

  • Accurate Clinical Research, LLC

    Baytown, Texas, 77521

  • Texas Orthopedic Specialist

    Bedford, Texas, 76021

  • First Surgical Hospital

    Bellaire, Texas, 77401

  • Legent Orthopedic Hospital

    Carrolton, California, 75006

  • Medvin Clinical Research

    Covina, California, 91722

  • CORE Orthopaedic Medical Center

    Encinitas, California, 92024

  • Accurate Clinical Research

    Houston, Texas, 77089

  • Marvel Clinical Research (Elite Clinical Network)

    Huntington Beach, California, 92647

  • AMR Kansas City

    Kansas City, Kansas, 64114

  • University of Kansas Medical Center

    Kansas City, Kansas, 66160

  • AMR Knoxville

    Knoxville, Tennessee, 37909

  • Accurate Clinical Research Inc.

    Lake Charles, Louisiana, 70605

  • AMR Lexington

    Lexington, Kentucky, 40509

  • K2 Medical Research

    Maitland, Florida, 32751

  • Drug Studies of America

    Marietta, Georgia, 30060

  • Wellness Research Center

    Miami, Florida, 33135

  • Well Pharma Medical Research

    Miami, Florida, 33173

  • Las Mercedes Medical Research

    Miami, Florida, 33196

  • Las Vegas Clinical Trials

    North Las Vegas, Nevada, 89030

  • Hightower Clinical

    Oklahoma City, Oklahoma, 73102

  • Medvin Clinical Research Center

    Riverside, California, 92518

  • Mayo Clinic (Rochester)

    Rochester, Minnesota, 55905

  • CenExel

    Salt Lake City, Utah, 84107

  • Wasatch Clinical Research

    Salt Lake City, Utah, 84107

  • Endeavor Clinical Trials

    San Antonio, Texas, 78229

  • Elite Clinical Network

    Scottsdale, Arizona, 85260

  • University Orthopedics Center

    State College, Pennsylvania, 16801

  • Noble Clinical Research

    Tucson, Arizona, 85704

  • Medvin Clinical Research Center

    Tujunga, California, 91042

  • Medvin Clinical Research Center

    Whittier, California, 90602

  • Center for Clinical Research

    Winston-Salem, North Carolina, 27103

Other trials in United States

About this study

Official title: A Randomized, Double-blind, Placebo-controlled, 53-Week Study Evaluating the Safety and Efficacy of Intra-articular Injections of TPX-100 in Subjects With Mild to Severe Tibio- Femoral Osteoarthritis of the Knee

53-Week Study Evaluating the Safety and Efficacy of Intra-articular (IA) Injections of TPX-100 vs Placebo in Subjects with Mild to Severe Tibio-Femoral Osteoarthritis of the Knee

Read the detailed description

This multicenter, double-blind, placebo controlled, randomized study is designed to investigate the safety and efficacy of TPX-100 administered in 4 weekly doses of 200 mg per dose in subjects with tibio-femoral osteoarthritis. The B-score as determined by MRI analysis is the final inclusion criteria, which will be determined by MRI-based assessment. A standardized screening MRI will be obtained on otherwise eligible candidates.

For enrolled subjects, the Screening MRI will serve as the Baseline MRI. Enrolled subjects will be assigned randomly to receive either TPX-100 or PBS placebo, 4 weekly IA injections administered into the target knee by fluoroscopy or ultrasound guidance.

Subjects will undergo follow-up knee MRIs at Week 27 and Week 53 after the first injection. All MRIs will be read by computer-based, standardized methods, blind to treatment assignment and temporal sequence, to provide the imaging outcome measures. Subjects will complete PROs at Week 1 (Baseline), Week 27 and Week 53. A clinical safety evaluation will be performed at Week 13, and a safety tele-visit or telephone call will be performed at Week 36. Adverse events, regardless of causation, and concomitant medications will be documented at all study visits and at the Week 37 tele-visit/telephone call. Clinical laboratory assessments will be obtained at Screening, Baseline (Week 1), and Weeks 2, 3, 4; and at the in-person follow up visits.

All enrolled subjects will be assigned randomly to receive either TPX-100 or PBS placebo, in 4 weekly IA injections administered into the target knee by fluoroscopy or ultrasound guidance.

Being tested
TPX-100 200mg, Once weekly for 4 weeks, PBS
Medical subject headings
Osteoarthritis

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • TPX-100 200mg, Once weekly for 4 weeksDrug

    TPX-100 (200 mg per dose) will be administered once-weekly (Week 1, 2, 3 \& 4) to a single target knee of the subject for 4 injections.

    TPX-100 can be administered by conventional methods such as subcutaneous or intra-articular injection.

  • PBSOther

    PBS / placebo for intra-articular injection administered once-weekly (Week 1, 2, 3 and 4) to a single target knee of the subject for 4 injections

Study groups in NCT06865079
Study groupRoleWhat they receive
TPX-100 (200 mg per dose)ExperimentalTPX-100 (200 mg per dose) for intra-articular injection administered once-weekly (Week 1, 2, 3 and 4) to a single target knee of the subject for 4 injections.
Receives: Drug: TPX-100 200mg, Once weekly for 4 weeks
Placebo / PBSPlacebo comparatorPBS placebo for intra-articular injection administered once-weekly (Week 1, 2, 3 and 4) to a single target knee of the subject for 4 injections.
Receives: Other: PBS

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Toxicity Reaction (CTC 5.0 standard）

    CTC 5.0, also known as Common Terminology Criteria for Adverse/Serious Adverse Events version 5.0, is an extensively used classification system for assessing drug toxicity. This system categorizes drug toxicity into five levels: Grade 0, Grade 1, Grade 2, Grade 3, and Grade 4.

    Measured: Baseline to Study Week 27 and Study Week 53

Secondary outcomes (3)

  1. Change in Physical Function & Pain of the Target Knee

    The Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC®) evaluation scales will be utilized to evaluate patient progression or benefit.

    WOMAC® is widely used in the evaluation of Knee Osteoarthritis. It is a patient self-administered questionnaire consisting of 24 items divided into 3 subscales:

    • Pain (5 items): during walking, using stairs, in bed, sitting or lying, and standing upright
    • Stiffness (2 items): after first waking and later in the day
    • Physical Function (17 items): using stairs, rising from sitting, standing, bending, walking, getting in / out of a car, shopping, putting on / taking off socks, rising from bed, lying in bed, getting in / out of bath, sitting, getting on / off toilet, heavy domestic duties, light domestic duties

    Measured: Baseline to Study Week 27 and Study Week 53

  2. Change in MRI-based femoral B-score which ranges from -2 to +7, with higher scores indicating greater severity

    To evaluate structural changes in subchondral bone in IA TPX-100-treated versus IA placebo-exposed knees.

    Measured: Baseline to Study Week 27 and Study Week 53

  3. To evaluate Pain Frequency in the Target Knee by KOOS evaluation of question 1 which ranges from 0 (Never) - 4 (Always).

    Evaluation of the frequency of pain in the target knee will be evaluated by the KOOS pain scale in which question 1 will be evaluated. Knee injury and Osteoarthritis Outcome Score (KOOS) is an extension of the WOMAC Osteoarthritis Index with the purpose of evaluating short-term and long-term symptoms and function in subjects with knee injury and osteoarthritis. The KOOS holds five separately scored subscales: Pain, other Symptoms, Function in daily living (ADL), Function in Sport and Recreation (Sport/Rec), and knee-related Quality of Life (QOL)

    Measured: Baseline to Study Week 27 and Study Week 53

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted7 Mar 2025
  2. Study start9 May 2025
  3. Primary completion25 Mar 2027 (estimated)
  4. Study completion15 Apr 2027 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Model description
Randomized, Double-blind, Placebo-Controlled
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
270 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06865079
Sponsor's protocol ID
TPX-100-6
Status last verified
Feb 2026
First submitted
25 Feb 2025
Last updated
17 Feb 2026
Results posted
No
FDA-regulated drug
Yes
FDA-regulated device
No

Questions about this trial

What is this clinical trial studying?

A Phase 2 study testing TPX-100 200mg, Once weekly for 4 weeks and PBS in people with Osteoarthritis (OA) of the Knee, run by OrthoTrophix, Inc at 33 sites in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 25 inclusion and 32 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: under way, not looking for participants, as of the sponsor's last update on 17 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 33 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Toxicity Reaction (CTC 5.0 standard） (time frame: Baseline to Study Week 27 and Study Week 53). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06865079.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Feb 2026.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in