Treatment of focal cartilage defects with a juvenile allogeneic 3-dimensional articular cartilage graft

DeNovo engineered tissue graft (recently renamed "RevaFlex") is a novel cellular therapy currently under Phase III investigation for cartilage regeneration. It is an in vitro-grown 3-dimensional hyaline-like cartilage tissue containing viable cultured juvenile allograft chondrocytes. Once expanded in vitro, juvenile chondrocytes are grown on a temporary polycarbonate membrane that is separated from the final tissue-engineered product at the time of packaging. The living cartilage allograft provides a chondrogenic, chondro-conductive, and chondro-inductive milieu. These immature chondrocytes are metabolically highly active and capable of spontaneous matrix formation, but do not stimulate an immune response. This is theorized to allow greater production of hyaline-like cartilage as opposed to fibrocartilage. In addition to the potential regenerative benefits, DeNovo engineered tissue avoids donor site morbidity, has the potential for greater cost efficiency, and is a potential single-step procedure. The authors describe a surgical technique, with supporting biochemical composition data, and review preliminary Food and Drug Administration Phase I/II data on the safety and efficacy of this new cartilage repair modality.