A Phase 3 interventional study of TG-C and Placebo Control in Degenerative Osteoarthritis, sponsored by Kolon TissueGene, Inc.. Completed at 27 sites in United States. Open to participants aged 40 Years and older. Per ClinicalTrials.gov, last updated 2026-08-20.
Sponsored by Kolon TissueGene, Inc. · Phase 3, Interventional, and Treatment
A randomized, double-blind, placebo-controlled, multi-center, phase 3 study to determine the efficacy and safety of TG-C in subjects with Kellgren and Lawrence Grade 2 or 3 Osteoarthritis of the Knee, Osteoarthritis Research Society International (OARSI) medial joint space narrowing (JSN) Grade 1 or 2 of the knee joint. TG-C is to be administered by a single intra-articular injection to the damaged joint area via ultrasound guidance. Patients will be followed for 24 months for safety and efficacy.
This protocol is designed to assess the safety and efficacy of TG-C in treating symptoms of osteoarthritis of the knee and determining disease modifying effects of TG-C. This study is intended for the treatment of patients with K\&L Grade 2 and 3 osteoarthritis and OARSI JSN Grade 1 and 2. Assessments will be made on both the symptomatic effects of pain (VAS), function (WOMAC), and Quality of Life (SF-12) as well as the physical effects (JSW, MRI evaluations of whole knee joint organ tissues and structure) and biochemical biomarkers. This is a placebo-controlled study, TG-C will be compared to normal saline as a control. Additionally, this protocol is designed to evaluate the safety of TG-C. Safety will be evaluated by observation of the injection site for irritation or other effects, the incidence and severity of adverse events, and changes in physical examination findings, radiographic criteria, and laboratory tests. Patients will be followed for 24 months for both safety and efficacy with annual cancer surveillance questionnaires through 15 years post dose for subjects who do not enroll in the Long Term Safety study.
386 studies on the registry are indexed under Joint Diseases; 64 are open to participants now.
This study's enrollment of 531 is above the median of 102 across 251 interventional studies indexed under Joint Diseases.
Browse Joint Diseases studies →Kolon TissueGene, Inc. is the lead sponsor of 6 studies on the registry; 2 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TG-C at 3 x 10e7 cells per single 2 mL intraarticular injection
Biological: TG-C
Normal saline, single 2 mL intraarticular injection
Biological: Placebo Control
2 mL injection of non-transduced human chondrocytes and irradiated transduced human GP2-293 cells expressing TGF-B1
Also known as: TissueGene-C
2 mL normal saline intraarticular injection
Also known as: Normal Saline
Change in Knee Function as Assessed by the Western Ontario and McMaster Universities Index (WOMAC)
Assessment of change from baseline in target knee function using the WOMAC Osteoarthritis Index. The WOMAC is a proprietary set of standardized questionnaires used by health professionals to evaluate the condition of patients with osteoarthritis of the knee including pain, stiffness, and physical functioning of the joints. The response to the questions is in the form of a checked box associated with the response; None, Mild, Moderate, Severe and Extreme.
Time frame: 12 months
Change in Knee Pain as Assessed by VAS
Assessment of change from baseline in target knee pain using the Visual Analog Scale (VAS). The VAS is a method for the assessment of the intensity of pain. The VAS is a horizontal line, 100 mm in length and anchored by word descriptors at each end (no pain, very severe pain). The patient marks on the line at the point that represents their current state. The VAS score is determined by measuring in millimeters from the left hand end to the point of the mark. The score ranges from "0" or no pain to "100" very severe pain.
Time frame: 12 months
MRI Assessment of Target Knee
Assessment of knee organ tissues and structure by comparing change in MRI scoring using WORMS
Time frame: 12 months
PCS of the SF-12 Questionnaire
Evaluation of the change from baseline in physical component score (PCS) of the SF-12v2 questionnaire.
Time frame: 12 months
WOMAC Total Score
Evaluation of the efficacy of TG-C with regard to knee function via WOMAC total score
Time frame: 24 Months
Health Assessment Questionnaire Disability Index
Evaluation of the change from baseline in the disability index of the Health Assessment Questionnaire (HAQ-DI)
Time frame: 12 months
Radiography for Structural Change in Knee Joint
Evaluate structural changes of the knee joint as determined by radiography (X-ray)
Time frame: 24 months
Efficacy of TG-C with Regard to Knee Function via WOMAC Total Score
Evaluation of the efficacy of TG-C with regard to knee function via WOMAC total score
Time frame: Week 1, Months 3, 6, 9, 12, 18, and 24
Efficacy of TG-C with Regard to Knee Function via WOMAC Pain, Function, and Stiffness Scores
Evaluate the efficacy of TG-C with regard to knee function via WOMAC® pain, function, and stiffness scores
Time frame: 24 months
Efficacy of TG-C with Regard to Knee Function via VAS Pain Score
Evaluation of the efficacy of TG-C with regard to knee function via VAS pain score at time points other than Month 12
Time frame: Day 1, Week 1, and Months 1, 3, 6, 9, 18 and 24
OMERACT-OARSI Responder Analysis
Analysis of response using the Outcomes Measures in Rheumatoid Arthritis Clinical Trials (OMERACT)-OARSI responder criteria
Time frame: 12 and 24 months
European Quality of Life-Five Dimensions Questionnaire (EQ-5D-5L)
Evaluate health outcomes using the European Quality of Life-Five Dimensions Questionnaire (EQ-5D-5L)
Time frame: Baseline and Months 3, 6, 9, 12, 18, and 24
Plan to share: No
No publications or documents are linked to this record.
Ran from Dec 2021 to primary completion in Mar 2024, 26 months.
Of 19 phase 3 interventional studies under Joint Diseases, half reached primary completion within 28 months of starting (the median), counting those still running; a quarter within 23 and three quarters within 38. This study's 26 months is close to that.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Kolon TissueGene, Inc.