The US Food and Drug Administration has approved what is reportedly the first autologous cellularized scaffold for the repair of cartilage defects of the knee.

The Maci (autologous cultured chondrocytes on porcine collagen membrane) implant, manufactured by Vericel Corp, headquartered in Cambridge, Mass, is composed of a patient’s own (autologous) cells that are expanded and placed onto a bio-resorbable (can be broken down by the body) porcine-derived collagen membrane that is implanted over the area where the defective or damaged tissue was removed.

Each Maci implant consists of a small cellular sheet containing 500,000 to 1,000,000 cells per cm2 (about 0.16 square inches). The amount of Maci administered depends on the size of the cartilage defect, and is trimmed to ensure that the damaged area is completely covered. Multiple implants may be used if there is more than one defect, according to an FDA news release.

The implant’s safety and efficacy were tested via a 2-year clinical trial designed to demonstrate reduced pain and improved function in comparison to microfracture, an alternative surgical procedure for cartilage repair. The trial included 144 patients (72 in each treatment group). The data from the trial, as well as a 3-year follow-up study, suggests there could be a long-term clinical benefit from the use of the Maci implant in patients with cartilage defects.

Common side effects were joint pain, common cold-like symptoms, headache and back pain.

[Source: US Food and Drug Administration]