|
General |
Study Status |
Completed |
Application Number / Requirement Number |
P110002 / PAS001 |
Date Original Protocol Accepted |
05/27/2014
|
Date Current Protocol Accepted |
05/27/2014
|
Study Name |
Extended f/u of premarket cohort
|
Device Name |
MOBI-C CERVICAL DISC PROSTHESIS (ONE-LEVEL INDICATION)
|
Clinical Trial Number(s) |
NCT00389597
|
General Study Protocol Parameters |
Study Design |
Prospective Cohort Study
|
Data Source |
New Data Collection
|
Comparison Group |
Concurrent Control
|
Analysis Type |
Analytical
|
Study Population |
Transit. Adolescent B (as adults) : 18-21 yrs,
Adult: >21
|
Detailed Study Protocol Parameters |
Study Objectives |
The primary objective of the study is to evaluate the overall long-term success rate (see primary end-points for the definitions) of the investigational device as compared to the control in subjects enrolled in the pivotal IDE study of the Mobi-C (1-levels) device (IDE Number G050212). Design-Prospective Cohort (extended follow-up of IDE patients)
|
Study Population |
All eligible Mobi-C patients treated at one level. All eligible fusion patients treated at one level under the LDR-001 Pivotal Study (IDE G050212)
|
Sample Size |
245 subjects are still enrolled in the study (at the time of the Primary Endpoint 24 month analysis) and eligible for long term follow-up in the post-approval study. This includes 155 randomized investigational subjects, 75 randomized control subjects, and 15 non-randomized training case (investigational) subjects.
|
Key Study Endpoints |
The primary endpoint of the study is individual patient success which is defined using the two measures of composite study success. 1. When assessing the composite endpoint, all components need to be successful for the endpoint to be considered a success. However, only 1 component needs to be a failure for the endpoint to be considered a failure. 2. Note: the data will be also analyzed for the primary outcome based on the 2nd definition for the success. See approval condition #1 and page 18 for the current submission.
|
Follow-up Visits and Length of Follow-up |
7-years
At 7th year
|
Interim or Final Data Summary |
Actual Number of Patients Enrolled |
Out of a total of 260 subjects from the pivotal study, 245 subjects were enrolled at 24 months and were eligible for long-term follow-up in the PAS: 155 randomized investigational subjects, 75 randomized control subjects, and 15 non-randomized training case (investigational) subjects.
|
Actual Number of Sites Enrolled |
The pivotal clinical study on one-level Mobi-c involved 24 sites.
|
Patient Follow-up Rate |
Out of 245 subjects enrolled in the PAS, there were 51 cumulative discontinuations. The follow up rate varied based on the follow up timepoint, study subgroup and data category. The Actual, efficacy in window follow up rate at the study’s end point (84-months) was reported as 60.3% for the Mobi-c group and 50% for the ACDF group.
|
Final Safety Findings |
No unexpected adverse events were identified based on the overall results from this PAS. As a result, one-level Mobi-c TDR is rendered as a safe alternative to the ACDF procedure using anterior plating with allograft.
|
Final Effect Findings |
Based on the overall success, as defined by the protocol-specified composite primary endpoint and alternative primary endpoints, the one-level Mobi-C device was shown to be as effective as the standard of care (ACDF). Non-inferiority for the one-level Mobi-C compared to ACDF with respect to individual subject success was demonstrated up to the study’s end point of 84 months.
|
Study Strengths & Weaknesses |
This Extended Follow-Up study was capable of demonstrating non-inferior, and in some instances superior, performance of the investigational one-level Mobi-c device compared to ACDF as control. However, a further performance analysis of the one-level Mobi-c disc may help with elucidating possible long-term complications such as underdiagnosed Adjacent Level Disease and progressing Heterotopic Ossification, which can hamper long-term motion preservation as the general premise of TDR. In addition, further research on possible sex-based differences in the performance of one-level Mobi-c and cervical fusion may augment the current device indications and may enable more informed pre-implantation risk-benefit assessment for the sex-stratified patient subgroups. Further research efforts may be also recomended for clarifying possible sex-related differences in Mobi-c performance at one level vs. two contigious levels: in contrast to a trend to higher overall success rates among males with one-level Mobi-c (P110002), males with the two-level Mobi-c experienced overall success less frequently, compared to their female counterparts (P110009).
|
Recommendations for Labeling Changes |
The current labeling for one-level Mobi-c is recommended to be updated based on long-term device performance (7-years). The labeling changes should include the following in particular: • Language that reflects that owing to possible indeterminate results of radiographic imaging (i.e., shoulder obstruction), the actual incidence of Adjacent Level Disease may be higher than that reported in both study groups. • Language describing the progression of Heterotopic Ossification which is statistically significant over time (i.e., 84 months vs. 24-months), but for which the clinical significance (e.g., possible ROM limitation despite the anticipated motion preservation in Mobi-c patients) has not been determined. • Language that mentions the possibility of some sex-related trends in device performance, such as a trend of higher likelihood of heterotopic ossification (=5 years post-implantation) in males vs. females with one-level Mobi-c.
|