Summary MACI (autologous cultured chondrocytes on porcine collagen membrane) is comprised of a patient’s own cells (autologous) for the repair of full thickness cartilage defects of the adult knee that are expanded in culture and seeded onto a resorbable porcine type I/III collagen film The MACI Membrane is implanted cell-side down into the prepared defect bed and secured using fibrin glue The resulting tissue exhibits properties similar to durable hyaline articular cartilage Indications and Usage MACI® is an autologous cellularized scaffold product indicated for the repair of symptomatic, single or multiple full-thickness cartilage defects of the knee with or without bone involvement in adults. Limitations of Use Effectiveness of MACI in joints other than the knee has not been established. Safety and effectiveness of MACI in patients over the age of 55 years have not been established. MACI is not recommended if you are pregnant. MACI has not been studied in patients younger than 18 or over 55 years of age. Common side effects include joint pain, tendonitis, back pain, joint swelling, and joint effusion. More serious side effects include joint pain, cartilage or meniscus injury, treatment failure, and osteoarthritis. Warnings and Precautions Malignancy The risk of MACI in patients with malignancy in the area of cartilage biopsy or implant is unknown. Expansion of malignant or dysplastic cells present in biopsy tissue during manufacture and subsequent implantation may be possible Transmissible infectious diseases Because patients undergoing procedures associated with MACI are not routinely tested for transmissible infectious diseases, cartilage biopsy and MACI implant may carry risk of transmitting infectious diseases. Presurgical Comorbidities Local inflammation or active infection in the bone, joint, and surrounding soft tissue, meniscal pathology, cruciate ligament instability, and misalignment should be assessed and treated prior to or concurrent with MACI implantation.</p> Product Sterility Final sterility test results are not available at the time of shipping. Adverse Reactions The most frequently occurring adverse reactions reported for MACI (≥5%) were arthralgia, tendonitis, back pain, joint swelling, and joint effusion. Serious adverse reactions reported for MACI were arthralgia, cartilage injury, meniscus injury, treatment failure, and osteoarthritis. Specific Populations Use of MACI in pediatric patients (younger than 18 years of age) or in patients over 65 years of age has not been established. The MACI implant is not recommended during pregnancy. For implantations post-pregnancy, the safety of breastfeeding to an infant has not been determined. Dosage Each 3 × 5 cm cellular sheet (MACI implant) consists of autologous cultured chondrocytes on a resorbable porcine Type I/III collagen membrane, at a density of at least 500,000 cells per cm². For autologous implantation only. The amount of MACI implanted depends on the size (surface area in cm²) of the cartilage defect. MACI should be cut to the size and shape of the defect and implanted with the cell-side down. Preoperative Planning and Surgical Considerations Clinical outcomes are associated with appropriate patient selection, joint optimization, and meticulous defect preparation. MRI imaging is considered the standard imaging approach to determine cartilage defect characteristics. Patient & Joint Assessment The following should be assessed and treated prior to or concurrent with MACI implantation: Local inflammation or active infection in the bone, joint, or surrounding soft tissue Meniscal pathology Cruciate ligament instability Malalignment MACI Surgical Technique Arthroscopic Evaluation and Cartilage Harvest Arthroscopic harvest of healthy cartilage from a lesser load-bearing region Obtain two healthy full-thickness specimens (~5 × 8 mm each; total ~200–300 mg) including a small amount of subchondral bone Specimens are used for autologous chondrocyte expansion and membrane seeding Defect Preparation Prepare stable vertical margins Remove unstable cartilage Avoid violation of the subchondral plate Establish a dry, blood-free field prior to implantation Implant Handling & Delivery (Arthroscopic or Open Arthrotomy) Confirm patient identifiers prior to implantation Determine delivery method: via arthroscopy (MACI Arthro instrumentation available) or via mini arthrotomy (open arthrotomy instrumentation available) Shape MACI Implant to match defect dimensions Maintain hydration until implantation Implant with the cell-side down Secure using fibrin per surgical training guidance Confirm stable fixation prior to closure Postoperative Management Outcomes may be influenced by patient adherence to a physician-prescribed rehabilitation program, which is highly individualized and typically includes staged progression of weight bearing and controlled range of motion. Contraindications MACI is contraindicated in patients with: Known history of hypersensitivity to gentamicin, other aminoglycosides, or products of porcine or bovine origin Severe osteoarthritis of the knee Inflammatory arthritis, inflammatory joint disease, or uncorrected congenital blood coagulation disorders Prior knee surgery (within 6 months), excluding surgery to procure a biopsy or a concomitant procedure to prepare the knee for a MACI implant Inability to cooperate with a physician-prescribed post-surgical rehabilitation program Disclaimers Please see Full Prescribing Information. Vericel Corporation has contributed to the content of this page. MACI®, Vericel®, and the Vericel logo are registered trademarks of Vericel Corporation. ©2026 Vericel Corporation. All rights reserved