A Phase III Study of CLS2901C in Patients With Osteoarthritis of the Knee

NCT06549686 | Recruiting Phase 3

• 1 other identifier: CLS2901-OAK-01
• Study Type: interventional
• Target: 96
• Locations: 1 country
• Sites: 6

Brief Summary

To evaluate the efficacy and safety of CLS2901C human allogenic chondrocyte sheets used in the osteotomy + RMSC group compared to in the osteotomy alone group of patients with osteoarthritis of the knee (OAK).

Conditions

Osteoarthritis of the Knee

Outcome Measures

Primary Outcomes (1)

• KOOS 4 score (The Knee injury and Osteoarthritis Outcome 4 score)

  Absolute change from baseline KOOS4 (Pain, Symptoms, ADL, QOL) score at postoperative Week 52. The four patient-relevant subscales of KOOS are scored separately: KOOS Pain (9items); KOOS Symptoms (7 items); KOOS ADL (17 items); KOOS QOL (4 items). A Likert scale is used and all items have five possible answer options scored from 0 (No Problems) to 4 (Extreme Problems). Scores are transformed to a 0-100 scale, with zero representing extreme knee problems and 100 representing no knee problems as is common in orthopaedic assessment scales and generic measures.

  52 weeks

Study Arms (2)

the osteotomy monotherapy group

NO INTERVENTION

the osteotomy monotherapy

the osteotomy + RMSC combination therapy group

EXPERIMENTAL

the osteotomy + RMSC combination therapy \*RMSC combination therapy R: Resection of unhealthy tissue MS: Marrow arrow Stimulating＝MSCs Recruitment C: Covered by Chondrocyte sheets

Biological: CLS2901C (human [allogeneic] chondrocyte sheets)

Interventions

CLS2901C (human [allogeneic] chondrocyte sheets) BIOLOGICAL

CLS2901C (human \[allogeneic\] chondrocyte sheets)

the osteotomy + RMSC combination therapy group

Eligibility Criteria

• Age: 20 Years - 79 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male or female aged 20 to 79 years at informed consent.
• Diagnosis of OAK classified as Kellgren-Lawrence (K-L) Grade 2 to 4 based on plain lower extremity X-ray.
• OAK eligible for proximal tibial osteotomy based on the following criteria: Range of motion (ROM): \>=120 degree flexion, \<=5 degree extension
• Preoperative cartilage defect of the femoral condyle/trochlear groove or medial tibial condyle with an area of \>=4 cm2 per defect site.
• Total defect area of \<=21 cm2 in individuals with multiple cartilage defects.
• Body mass index (BMI) \<30.
• No coexisting ligament injury requiring surgery, and no meniscal injury requiring suturing or surgical repair other than partial resection, in the target knee.
• No history of ligament reconstruction, meniscal suturing, total meniscectomy or bone marrow stimulation, and no history of treatment with regenerative medicine products (including investigational products), cell processing products or gene therapy, in the target knee.
• No history of treatment with hyaluronic acid products and/or opioid for severe pain in the target knee within 1 month prior to informed consent.
• No history of treatment with corticosteroid products and/or immunosuppressive drug in the target knee within 3 months prior to informed consent.
• No history of platelet-rich plasma (PRP) therapy within 6 months prior to informed consent.
• Non-smoker; provided, however, that smokers will be eligible for study entry if they consent to abstain from smoking from 3 months prior to proximal tibial osteotomy or proximal tibial osteotomy+RMSC until postoperative bone healing.
• Written informed consent to participate in the study on a voluntary basis.

You may not qualify if:

• Requires surgical treatment of the non-target knee during the study period.
• Any coexisting illness that would interfere with surgery under general anesthesia or that would affect knee surgery.
• Systemic inflammatory disease such as rheumatoid arthritis.
• Systemic Active infectious disease such as bacterial, fungal or viral infection.
• \) Serious disease such as liver disorder, renal disorder, heart disease, lung disease, blood disease or metabolic disease that would make the patient unsuitable for study entry in the opinion of the investigator.
• \) Diagnosed or suspected malignant tumor or history of malignant tumor within the past 5 years.
• \) Uncontrolled psychiatric disorder. 9) Poorly-controlled diabetes (HbA1c: \>7.0%). 10) septic arthritis of the target knee. 11) Women who are pregnant or breastfeeding, or women of childbearing potential. Women of childbearing potential must agree to use the following contraceptive methods (i.e., contraceptives and medical devices that are approved/certified in Japan) or to abstain completely from sexual intercourse from the time of informed consent and for the study duration (excluding the follow-up period) in order to be eligible for study entry. (a) Primary contraceptive methods: Oral contraceptives, intrauterine devices (IUDs) including progesterone-releasing systems. (b) Adjunctive contraceptive methods: Condoms Use of a primary contraceptive method is mandatory, whereas use of the adjunctive contraceptive method must be in conjunction with a primary contraceptive method. Given that oral contraceptive doses can be missed and that their effects may be diminished when used concomitantly with other medications or dietary health supplements, subjects should consider changing their primary contraceptive method.
• \) Participated in another clinical study within the past 6 months, currently participating in another clinical study, or planning to participate in another clinical study while also participating in the present study.
• \) Known history of hypersensitivity to antibiotics (benzylpenicillin potassium, streptomycin sulfate, amphotericin B).
• \) Known history of hypersensitivity to bovine-derived materials. 15) Any other reason the investigator deems the subject unsuitable for study entry.

Sponsors & Collaborators

• CellSeed Inc.: lead

Study Sites (6)

Ebina General Hospital/Ebina Medical Plaza

Ebina, Kanagawa, 243-0433, Japan

RECRUITING

Tokai University Hospital

Isehara, Kanagawa, 259-1193, Japan

RECRUITING

Yokohama Sekishinkai Hospital

Yokohama, Kanagawa, 230-0062, Japan

RECRUITING

Yokohama City University Medical Center

Yokohama, Kanagawa, 232-0024, Japan

RECRUITING

Yokohama Minami Kyousai Hospital

Yokohama, Kanagawa, 236-0037, Japan

RECRUITING

Juntendo University Hospital

Bunkyō-Ku, Tokyo, 113-8431, Japan

RECRUITING

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Officials

• Manabu Ishizuka

  CellSeed Inc.

  STUDY DIRECTOR

Central Study Contacts

Chikako Sato

CONTACT

+81-03-6380-7490; cs.clinicaldevelopment@cellseed.com

Kari Muraoka

CONTACT

+8170-1278-5948; kari.muraoka@cellseed.com

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 8, 2024
• First Posted: August 12, 2024
• Study Start: October 20, 2023
• Primary Completion (Estimated): July 31, 2027
• Study Completion (Estimated): July 31, 2031
• Last Updated: November 24, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

JP (6)