This abstract presents the 5-year follow-up results of a previously published prospective randomized controlled trial. 30 patients with an International Cartilage Repair Society (ICRS) grade 3 to 4 chondral defect in the knee were randomized to receive costal chondrocyte–derived pellet-type autologous chondrocyte implantation (CCP-ACI; n=20) or microfracture (MFx; n=10). 25 of these patients were followed-up at 5 years. Outcomes of interest included the Lysholm score, International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analog Scale (VAS) pain score, Magnetic resonance Observation of Cartilage Repair Tissue (MOCART) score, and treatment failure, all assessed at 5 years. In the CCP-ACI group, MOCART, Lysholm and KOOS scores improved significantly from baseline compared the the MFx group. One treatment failure was reported in the MFx group.