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NCT06915233ClinicalTrials.gov

A Study of MACI in Patients Aged 17 to 65 Years With Symptomatic Chondral or Osteochondral Defects of the Ankle

A Prospective, Open-label, Randomized, Concurrent Active-controlled, Longitudinal, Multicenter, Phase 3 Clinical Study of the Safety and Efficacy of MACI in Patients With Symptomatic Chondral or Osteochondral Lesions of the Talus (MASCOT)

RecruitingTaking participants now, according to the registry record.
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In brief

The objective of this study is to demonstrate the superiority of MACI (autologous cultured chondrocytes on porcine collagen membrane) versus Bone Marrow Stimulation in the treatment of patients aged 17 to 65 years with symptomatic articular chondral or osteochondral defects…

Phase 3309 participants sought7 sites1 country

Categories

Registered in 1 registry

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Trial information is shown as published by the registry, in its original language.

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How this study is set up

The points below are drawn from the public registry record for this study. Each one cites the field or sentence it came from. A dash (—) means the record does not state something — not that it is missing or wrong. Many well-run studies, especially small ones, leave some of these blank.

  • Present: Registered before enrolment beganFirst posted 2025-04-08; recorded start 2026-05-28
  • Present: Has a defined primary outcomeA primary outcome measure is listed in the record
  • Present: The primary outcome states a time frameThe primary outcome measure records a time frame
  • Present: Participants are randomly assignedAllocation is recorded as randomised
  • Present: Has a comparison groupThe record lists a placebo or comparator arm, or more than one study arm
  • Not stated: Open label (no blinding)Masking is recorded as none (open label)
  • Not stated: An ethics committee is not stated in the registry recordThis registry's ingested record has no ethics-committee field
  • Not stated: Regulatory oversight (such as an IND or IDE) is not stated in the registry recordThis registry's ingested record has no regulatory-authorisation field
  • Not stated: A data monitoring committee is not stated in the registry recordThis registry's ingested record has no data-monitoring-committee fieldA data monitoring committee is not required for many smaller studies, and its absence here is not unusual.
  • Present: No cost to participants is mentioned in the recordChecked the summary, description and eligibility text; no cost-to-participant phrase found
  • Present: Sponsor has 1 other study in this databaseCounted from the lead sponsor named in the record (Vericel Corporation)
  • Not stated: No posted results from this sponsor are in this database yetBased on the sponsor’s studies in this database
  • The record lists 2 conditions.
  • Lead sponsor type recorded as: industry.
  • Intervention regulatory context: investigational, within a phased regulatory pathway.

Trial stature

Three independent measures of this study, described from its registry record — not a recommendation about it. A rigorous study by investigators nobody has heard of is better evidence than a weak study led by a famous one. How these are scored.

Methodological rigourMODERATE

A moderately rigorous design for a phase 3 study, judged from its ClinicalTrials.gov record.

How this score is built
  • Randomised allocation20/20

    Participants are randomly allocated between arms

  • Blinding0/20

    Open-label

  • Control arm0/15

    No comparator arm stated in the record

  • Primary-outcome specificity10/10

    Named primary outcome with a defined time frame

  • Endpoint type3/10

    Surrogate or intermediate endpoint (conservative default)

  • Multi-centre5/8

    Multi-centre: 7 sites

  • Data monitoring committee7/7

    A data monitoring committee is in place

  • Prospective registration5/5

    Registered before the study start date

  • Protocol / SAP posted0/5

    No protocol or SAP posted to the registry

ScaleMEDIUM

A medium-sized study: 309 participants (target), run at 7 sites.

How this score is built
  • Enrolment24/40

    309 participants (target)

  • Site count10/25

    7 sites

  • Country count0/15

    Single country

  • Planned duration9/10

    Planned over about 50 months

  • Sponsor scale1/10

    Vericel Corporation has led 2 trials in our corpus

Investigator standingUNKNOWN

We have no verifiable track record for the investigator named on this trial. That is common for early-career investigators and for records held outside ClinicalTrials.gov — it is not a negative signal.

How this score is built
  • Investigator standing0/100

    No investigator recorded in the registry for this trial

These describe the registry record only, and today we hold ClinicalTrials.gov data. Absent fields lower a score, and absence often reflects registration practice rather than study quality. A high-stature trial is not necessarily safer or a better choice for you — enrolling in a large definitive trial can mean a higher chance of receiving placebo, while a small early-phase study may be the only route to a new therapy.

Summary

The objective of this study is to demonstrate the superiority of MACI (autologous cultured chondrocytes on porcine collagen membrane) versus Bone Marrow Stimulation in the treatment of patients aged 17 to 65 years with symptomatic articular chondral or osteochondral defects of the talus.

This is a 2-year prospective, multicenter, two-arm, parallel-group open-label clinical trial in which a total of 309 subjects, ages 17 to 65, will be randomized 2:1 to receive a 1-time treatment in the ankle with MACI or arthroscopic BMS. After meeting screening criteria at the initial visit (Visit 1), all participants will have an index ankle arthroscopy within 8 weeks to further assess clinical trial eligibility. During the index ankle arthroscopy (Visit 2), participants will be further evaluated against entry criteria. Cartilage lesion size will be measured before randomization and any cartilage repair procedure. Only participants with at least 1 lesion ≥ 1.2 cm² on the talus will be eligible for inclusion in the clinical trial. All participants who meet the eligibility criteria and are considered suitable for treatment in the clinical trial by their surgeon will have a cartilage biopsy taken prior to randomization to study treatment. Eligible participants will be randomized 2:1 to receive either MACI or Bone Marrow Stimulation. Participants randomized to Bone Marrow Stimulation will undergo the procedure during the Visit 2 ankle arthroscopy. Subjects will be asked to follow a recommended postoperative rehabilitation program. All biopsied tissue will be sent to the Vericel Corporation manufacturing facility in Massachusetts, where the sample will be processed to isolate the autologous chondrocytes, undergo cell culture expansion through at least the primary phase, and cryopreservation. Additional expansion of the cells will occur after the MACI implantation surgery has been scheduled. Participants assigned to the MACI treatment arm will return within 5 to 12 weeks of the Visit 2 ankle arthroscopy to undergo MACI implantation procedure via arthrotomy (Visit 3). Participants will be asked to follow a recommended postoperative rehabilitation program. All subjects will be assessed post-study treatment at Weeks 6 and 12 for safety and at Weeks 24, 36, 52, 78, and 104 for safety and efficacy. Rehabilitation status will be monitored at all post-treatment visits through Week 52.

Conditions

  • Chondral Defect
  • Articular Cartilage Defect

Eligibility

Eligibility
SexAll
Ages17 Years65 Years
Healthy volunteersNo

Eligibility as written in the registry

Inclusion Criteria: 1. Age 17 to 65 at the time of planned randomization visit (Visit 2). 2. One or more symptomatic chondral or osteochondral lesion/s as defined by FAOS Pain score ≤ 50 and FAOS Function (SRA) score ≤ 50. 3. International Cartilage Repair Society (ICRS) Score Grade 3 or 4 chondral or osteochondral lesion/s located on the talus with or without cysts, including shoulder lesions (lesions on the talar neck), and amenable to treatment with the surgical procedure specified at randomization. 4. At least 1 lesion ≥ 1.2 cm². 5. Written informed consent and assent (as applicable) per Institutional Review Board (IRB) requirements. 6. Participant will refrain from using Non-steroidal Anti-inflammatory Drugs (NSAIDS) for 12 weeks post-study treatment. (Post-surgical use of low-dose aspirin for clot prevention is acceptable). 7. Participant will restrict pain medication to over-the-counter analgesics (NSAIDs or acetaminophen/paracetamol) after 12 weeks post-study treatment. 8. Participant must have Hematocrit ≥30.0%; White Blood Cell count ≤14,000 cells/μL; Platelet Count ≥50,000 platelets/μL; Creatinine ≤2.0 mg/dL; and International Normalized Ratio (INR) ≤1.6. Exclusion Criteria: 1. Lesions with an underlying bony defect depth of \> 5 mm. 2. Any surgery on the target joint within 24 weeks prior to Visit 1 (not including diagnostic ankle arthroscopy). 3. Previous investigational drug, biologic or device use within 12 weeks prior to Visit. 4. Avascular necrosis of the target ankle. 5. Symptomatic musculoskeletal conditions in the lower limbs that could impede measurement of efficacy for the target ankle joint. 6. Participant with "kissing lesions" (bipolar lesions, involving both the tibia and talus), or with bilateral lesions in both ankles. 7. Participant with lesions that require an osteotomy procedure to allow for MACI implantation as determined at the time of ankle arthroscopy (Visit 2). 8. Concomitant systemic inflammatory diseases or other conditions that affect the joints (e.g., rheumatoid arthritis, metabolic bone disease, psoriasis, symptomatic chondrocalcinosis). 9. History of advanced or severe osteoarthritis of the ankle as determined by prior surgical history confirming no joint space (i.e., "bone on bone") or radiographic evidence of Modified Kellgren-Lawrence Grade 4 arthritis (i.e., osteophytes on lateral and medial malleoli and at the tibiotalar joint margins, narrowing of the joint space width \> 50%, and tibiotalar sclerosis), Van Dijk Grade III (i.e., total or subtotal destruction of the joint space) or the equivalent. 10. Known history of septic arthritis in the target ankle joint within 1 year prior to Visit 1. 11. Current malignancy or treatment for malignancy within the past 5 years prior to Visit 1, excluding non-melanoma skin cancer. 12. Known history of hypersensitivity to gentamicin, other aminoglycosides, or products of porcine or bovine origin. 13. Females who are pregnant or lactating. 14. Patients who, in the opinion of the Investigator, have significant medical or psychosocial problems that warrant exclusion. Examples of significant problems included but are not limited to: 1. Any condition that has potential for negatively impacting intra- or postoperative course (e.g., uncontrolled diabetes, heavy smoking). - Uncontrolled diabetes is defined as hemoglobin A1c (HbA1c) ≥8.0% and/or fasting plasma glucose \>250 mg/dL (13.9 mmol/L) within the last 90 days prior to Screening Visit 1 - Heavy smoking is defined as current smoker with use of ≥20 cigarettes per day (≥1 pack/day) at the time of Screening Visit 1. 2. Conditions that limit compliance with rehabilitation program. 3. Any condition that has potential for significantly limiting participant's ability to assess postoperative ankle function. 4. Any condition, psychiatric or otherwise, that would preclude informed consent/assent, consistent follow-up, or compliance with any aspect of the clinical trial. 5. Participant is currently abusing drugs or alcohol or, in the opinion of the Investigator, at high risk for poor compliance. 6. Any abnormal screening blood work that the Investigator deems clinically significant in addition to the parameters delineated in Inclusion Criterion #8. 15. Injection of hyaluronic acid (HA), platelet-rich plasma (PRP), and/or corticosteroids in the target ankle within 90 days prior to Visit 1.

Eligibility in plain statements

This record's criteria have not been broken into separate statements yet. The registry text above is complete and is the authoritative version.

Study design

Study design
Study typeInterventional
PhasePhase 3
AllocationRandomised
Intervention modelPARALLEL
Primary purposeTREATMENT
MaskingNONE (0)
Enrolment309 participants sought

Sponsor and collaborators

  • Vericel Corporation Sponsor

Arms and interventions

  • MACIEXPERIMENTAL

    autologous cultured chondrocytes on porcine collagen membrane

  • Bone Marrow StimulationOTHER

    Surgical procedure

Interventions

  • Procedure Bone Marrow Stimulation

    A surgical awl or microdrill will be used to make multiple holes in the exposed base of the lesion. The microfracture procedure should result in holes that are approximately 3 to 4 mm apart. When fat droplets can be seen coming from the marrow cavity, the appropriate depth (approximately 2 to 4 mm) has been reached. The released marrow elements (including mesenchymal stem cells, growth factors, and other healing proteins) form a surgically induced clot that provides an enriched environment for new tissue formation.

  • Biological autologous cultured chondrocytes on porcine collagen membrane

    An autologous cellularized scaffold combination product being studied for the repair of symptomatic, single or multiple full-thickness cartilage defects of the talus with or without bone involvement in adults.

Outcome measures

  1. Primary outcome

    Change from Baseline to Week 104 in the FAOS Pain and Function (SRA) subscale scores

    The FAOS is a 42-item, patient-reported outcome measure that assesses foot and ankle health in the past week. There are five FAOS subscales: Pain, Symptoms, Function (Daily Living), Function (SRA), and Foot and Ankle Related Quality of Life. The FAOS has been validated for a variety of foot and ankle conditions, including OLT. Responses to each question on the FAOS are recorded on a 5-point Likert scale. A normalized score out of 100 is calculated for each subscale, with 0 indicating extreme symptoms and 100 no symptoms. Selection of this composite primary endpoint is consistent with FDA guidance recommending selection of primary endpoints that evaluate changes in Pain and Function (SRA) subscale scores as they represent clinically meaningful outcomes for participants who receive products intended to repair or replace damaged cartilage in the knee.

    Time frame Baseline to Week 104

  2. Secondary outcome

    Percentage of participants who respond to study treatment after 2 years, i.e., participants who have ≥ 10-point improvement on both the FAOS Pain and Function (SRA) subscale scores from Baseline to Week 104.

    The FAOS is a 42-item, patient-reported outcome measure that assesses foot and ankle health in the past week. There are five FAOS subscales: Pain, Symptoms, Function (Daily Living), Function (SRA), and Foot and Ankle Related Quality of Life. The FAOS has been validated for a variety of foot and ankle conditions, including OLT. Responses to each question on the FAOS are recorded on a 5-point Likert scale. A normalized score out of 100 is calculated for each subscale, with 0 indicating extreme symptoms and 100 no symptoms.

    Time frame Baseline to Week 104

  3. Secondary outcome

    Change from Baseline to Week 104 in the remaining FAOS subscales scores [Symptoms, Function (Daily Living) and Quality of Life]

    The FAOS is a 42-item, patient-reported outcome measure that assesses foot and ankle health in the past week. There are five FAOS subscales: Pain, Symptoms, Function (Daily Living), Function (SRA), and Foot and Ankle Related Quality of Life. The FAOS has been validated for a variety of foot and ankle conditions, including OLT. Responses to each question on the FAOS are recorded on a 5-point Likert scale. A normalized score out of 100 is calculated for each subscale, with 0 indicating extreme symptoms and 100 no symptoms.

    Time frame Baseline to Week 104

Dates

Dates
Start dateMay 28, 2026 (actual)
Primary completionJuly 1, 2030 (estimated)
CompletionJuly 1, 2030 (estimated)
First postedApril 8, 2025 (actual)
Last updatedJuly 23, 2026
Results postedNot stated in the registry record
Status last verifiedJuly 2026

Actual means the event happened. Estimated means the sponsor expects it. The two mean different things.

Locations

7 sites are recruiting

United States

United States
FacilityCityState or regionStatus
University of VirginiaCharlottesvilleVirginiaRecruiting
Duke Orthopaedic SurgeryDurhamNorth CarolinaRecruiting
Elevate Clinical ResearchHoustonTexasRecruiting
UC Davis Foot and Ankle ClinicSacramentoCaliforniaRecruiting
Rodaro, LLCSan AntonioTexasRecruiting
MedStar Georgetown University HospitalWashington D.C.District of ColumbiaRecruiting
Elevate Clinical Research WichitaWichitaKansasRecruiting

Study documents

No documents are linked in this registry record.

Changes over time

No changes have been recorded since we first ingested this record.

A change is recorded each time the sponsor updates the registry record. Status, dates, enrolment and sites appear here as they move.