MACI: Proven in
clinical studies

efficacy demonstrated in 3 key areas

A durable repair tissue

In the SUMMIT Trial, at 2 years post-treatment, most patients in the MACI group had nearly normal (Grade II) or normal (Grade I) overall repair assessment tissue with features similar to normal articular cartilage.1

About the summit Extension trial¹

The SUMMIT Extension Trial was an open-label, multicenter extension of the Summit Trial. The study continued to show a favorable safety and clinical outcome at five years consistent with the two year results.

Pain and function

The MACI implant demonstrated statistically signficantly greater improvement in both pain and function than microfracture at 2 years as shown in Knee Injury and Osteoarthritis Outcome Score (KOOS).1   

MACI is indicated for the repair of single or multiple symptomatic, full-thickness cartilage defects of the adult knee, with or without bone involvement.

KOOS scale changes in pain over time

KOOS scale changes in function over time


In the SUMMIT follow-up extension study, the mean KOOS pain and function scores seen in both treatment groups at Year 5 were consistent with those seen at Year 2.2


clinical experience 

In a responder analysis, the proportion of subjects with at least a 10-point improvement in both KOOS Pain and Function (SRA) was greater in the MACI group (63/72=87.5%; 95% CI [77.6%, 94.1%]) compared with the microfracture group (49/72=68.1%; 95% CI [56.0%, 78.6%]).1

Safety demonstrated in the SUMMIT trial

No unexpected safety events were reported.1

Most treatment-emergent adverse reactions were of moderate or mild intensity, the most common being arthralgia (51.4%), back pain (11.1%), and joint swelling (9.7%).1

Fewer treatment-emergent serious adverse reactions were reported with MACI than with microfracture. Only 13 adverse reactions in the MACI group (n=72) were considered serious versus 25 adverse reactions in the microfracture group (n=72).¹

Patients in the microfracture group experienced more cases of treatment failure, cartilage injury, and arthralgia.


The safety of MACI in patients with malignancy in the area of cartilage biopsy or implant is unknown. Expansion of present malignant or dysplastic cells during the culturing process or implantation is possible.


MACI unlocks the potential of your patient's own cells.
See the science behind MACI

1. Saris D, Price A, Widuchowski W, et al. Matrix-applied characterized autologous cultured chondrocytes versus microfracture: Two-year follow-up of a prospective randomized trial. Am J Sports Med. 2014;42(6):1384-94.

2. Brittberg M, Recker D, Ilgenfritz J, et al., Matrix-Applied Characterized Autologous Cultured Chondrocytes Versus Microfracture Five-Year Follow-up of a Prospective Randomized Trial. Am J Sports Med. 2018;46(6): 1343-1351.