Results
The data expressed here is a summary of the clinical results from Genzyme Tissue Repair’s Cartilage Repair Registry as presented at the annual American Academy of Orthopedic Surgeons meeting in February 1999. This registry was reported to from 440 U.S. sites, 140 European sites (outside of Sweden) and 3 Israel sites and is a means for tracking and analyzing the outcomes for patients treated with Carticel. The U.S. registry results confirm and are consistent with the positive results experienced by Swedish orthopedic surgeons. ACI has been used successfully in Sweden since 1987, whereas Carticel was introduced to the U.S. in 1995. This U.S. registry data reports clinical outcomes up to 3 years after the time of treatment.
PATIENT PROFILE
-average age of 35 years with 97% between 15 and 55 years
-all had femoral condyle lesions with or without concurrent non-cartilaginous knee lesions
-90% of the lesions are on the distal femur
-90% had defects or lesions less than 10 square cm
-average defect size after debridement is 4.6 square cm
-size range of defects from less than 1-20 square cm
-71% have had some kind of previous surgery
CLINICAL OUTCOMES
The following chart considers the response of 40 patients to the Carticel treatment, although the means of this patient selection was not reported.
This indicates that a total of 70% of the treated patients demonstrated some functional benefit from the ACI treatment.
Of the reported patients that were treated with ACI who had also had a previous surgery, 59% (13/22) had outcomes that were functionally favorable as compared to the outcomes of those previous surgeries.
There wasn’t an apparent association with the clinical outcome of the treatment with respect to the size of the lesion or the cell dose that was administered.
These tables summarize the patient and clinician evaluations at 24 months after ACI treatment as compared to their pre-operative baseline condition.
Patient Evaluation
|
|
n |
Improve % |
Same % |
Decline % |
Mean Change in Score* |
|
MFC |
16 |
81% |
13% |
6% |
(+) 4.25 |
|
LFC |
4 |
100% |
0% |
0% |
(+) 6.50 |
|
Trochlea |
2 |
100% |
0% |
0% |
(+) 4.00 |
|
Femur |
27 |
85% |
7% |
7% |
(+) 4.48 |
Clinician Evaluation
|
|
n |
Improve % |
Same % |
Decline % |
Mean Change in Score* |
|
MFC |
15 |
80% |
13% |
7% |
(+) 4.33 |
|
LFC |
4 |
100% |
0% |
0% |
(+) 6.50 |
|
Trochlea |
2 |
100% |
0% |
0% |
(+) 3.00 |
|
Femur |
26 |
85% |
8% |
8% |
(+) 4.54 |
*Note: Based on a modified Cincinnati Knee Rating System with a scale of 0-10, where a score of 2 is poor and a score of 10 is excellent.
The following graph summarizes patient reported symptoms following the ACI treatment as compared to the pre-operative baseline condition. It is important to note that patients were not excluded from this data if the treatment was considered a failure.
It is interesting to see that there was a decrease in the presence of joint line pain from 24 months to 36 months when there was an overall increase in the presence of swelling over that same time period. An explanation of this phenomenon was not reported.
SAFETY PROFILE / ADVERSE EVENTS
The following chart represents the safety profile data reported of 1896 patients.
The re-operations (5%) were considered to be possibly related to the implantation. The majority of these re-operations were typically arthroscopic and involved shaving, trimming and/or lysis of adhesions.
The overall incidence of treatment failure is 3.2% at 24 months and 4.7% at 36 months.
List of the adverse events from most to least common:
-intra-articular adhesions
-hypertrophic tissue
-superficial wound infection
-hypertrophic synovitis
-post-operative hematoma
-adhesions of the bursa suprapatellaris
-hypertrophic synovium
CONCLUSIONS
85% of femoral condyle patients showed some kind of knee condition improvement at 36 months, as rated by both themselves and the clinicians.
No operations following the implantation was reported by 91% of the patients.
The incidence of treatment failure is relatively low. (4.7% at 36 months)
The results presented seem to confirm that autologous cultured chondrocytes continue to be safe and effective at 24 and 36 months.
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