The FDA this week announced approval of Maci, â€œmatrix-induced autologous chondrocyte implantation.â€ The treatment is intended for cartilage defects of the knee, which can eventually lead to osteoarthritis.
The US Food and Drug Administration (FDA) this week announced approval of Maci, which stands for “matrix-induced autologous chondrocyte implantation.” The treatment is intended for cartilage defects of the knee, which can eventually lead to osteoarthritis. The implants are approved for use in adult patients. Maci is the first product in which the patient’s own healthy tissue is used to grow cells on scaffolds through the process of tissue engineering.
Cartilage defects in the knee are common, and can be caused by injury, disease, overuse, or simply normal wear and tear. People of all ages are susceptible to knee problems. According to Celia Witten, PhD, MD, deputy director of the FDA’s Center for Biologics Evaluation and Research, “Different cartilage defects require different treatments, so therapy must be tailored to the patient.”
Each implant is a cellular sheet, and the size of that sheet depends in part on the individual patient’s particular cartilage defect. Typically, the sheets vary from 500,000 to 1,000,000 cells per cm2. Maci is made up of a bioresorbable, porcine-derived collagen membrane, with autologous cells on it. More than one implant may be used if there are multiple defects.
Maci is an alternative to microfracture, and was tested for safety and efficacy in a two-year trial called Superiority of MACI Implant to Microfracture Treatment (SUMMIT). The trial included 144 patients, with 72 in the Maci group and 72 in the microfracture group. The majority of patients (128) participated in a three-year follow-up study (SUMMIT Extension) as well. Both studies concluded that Maci was more effective than microfracture treatment, and equally as safe.
Maci is manufactured by Vericel, previously Aastrom Biosciences, and has been approved for use in Europe for several years. However, the product sold poorly in Europe due to high cost, and the company halted manufacturing there in 2014. Following the FDA approval on Tuesday, shares of the company surged domestically by more than 50%.