Post-Approval Studies (PAS) Database

The FDA has the authority to require sponsors to perform a post-approval study (or studies) at the time of approval of a premarket approval (PMA), humanitarian device exemption (HDE), or product development protocol (PDP) application. Post-approval studies can provide patients, health care professionals, the device industry, the FDA and other stakeholders information on the continued safety and effectiveness (or continued probable benefit, in the case of an HDE) of approved medical devices. This database allows you to search Post-Approval Study information by applicant or device information.

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The Tether Vertebral Tethering System PAS

General
Study Status	Delayed
Application Number / Requirement Number	H190005 / PAS001
Date Original Protocol Accepted	01/13/2020
Date Current Protocol Accepted	06/10/2025
Study Name	The Tether Vertebral Tethering System PAS
Device Name	The Tether™ - Vertebral Body Tethering System
Clinical Trial Number(s)	NCT02897453
General Study Protocol Parameters
Study Design	Prospective & Retrospective Study
Data Source	Sponsor Registry
Comparison Group	No Control
Analysis Type	Descriptive
Study Population	Child: 2-12 yrs, Adolescent: 13-18 yrs, Transit. Adolescent B (as adults) : 18-21 yrs
Detailed Study Protocol Parameters
Study Objectives	The objective is to assess the ongoing safety and probable benefit of The Tether in a registry population.The study design is a single-arm, prospective, multicenter cohort, registry study.
Study Population	The study population is comprised of skeletally immature patients that require surgical treatment to obtain and maintain correction of progressive idiopathic scoliosis who receive the device in the post market environment. There is no comparator group.
Sample Size	At least 193 patients will be enrolled.
Key Study Endpoints	The primary probable benefit endpoint is the percentage of patients with maintenance of the major Cobb angle less than or equal to 40 degrees at 60 months post-surgery. The primary safety endpoints are serious adverse events (SAEs), and device- or procedure-related AEs.
Follow-up Visits and Length of Follow-up	Patients will be followed through 60-months from the time of each patient's index surgery.
Interim or Final Data Summary
Actual Number of Patients Enrolled	Across 9 sites, 89 patients were actively enrolled. However, two MSH patients were removed due to data quality issues, such as late or missing data, missed protocol visits, and non-compliance with the protocol. Thus, the current number of subjects actively enrolled is 87.
Actual Number of Sites Enrolled	9 active sites
Patient Follow-up Rate	Two patients at the MSH site were excluded from the study due to the discontinuation of the MSH site. The sponsor noted data quality issues such as late data and missed protocol visits.

The Tether Vertebral Tethering System PAS Reporting Schedule

Reporting Schedule	Report Date Due	FDA Receipt Date	Applicant's Reporting Status
6 month report	08/31/2020	08/31/2020	On Time
1 year report	03/01/2021	03/01/2021	On Time
18 month report	08/31/2021	08/31/2021	On Time
2 year report	03/01/2022	03/11/2022	Overdue/Received
3 year report	03/31/2023	03/24/2023	On Time
4 year report	03/01/2024	03/25/2024	Overdue/Received
5 year report	04/03/2025	04/04/2025	Overdue/Received
final report	11/30/2027

Contact Us

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Mandated Studies Program
Food and Drug Administration
10903 New Hampshire Ave.
Silver Spring, MD 20993-0002
Email: MandatedStudiesPrograms@fda.hhs.gov

Additional Resources

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• Guidance Document: "Procedures for Handling Post-Approval Studies Imposed by PMA Order"
• PAS Program Background