In January 2005, the oversight responsibility of the Post-Approval Studies Program was transferred to the Division of Epidemiology (DEPI) of the Office of Surveillance and Biometrics (OSB)/Center for Devices and Radiological Health (CDRH).
The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a premarket approval (PMA) application, protocol development product (PDP) application, or humanitarian device exemption (HDE) application. The program helps ensure that well-designed post-approval studies (PAS) are conducted effectively and efficiently and in the least burdensome manner.
CDRH has established an automated, internal tracking system that efficiently identifies the reporting status of active PAS studies ordered since January 1, 2005 based on study timelines incorporated in study protocols and agreed upon by the CDRH and applicants. This system represents CDRH's effort to ensure that all PAS commitments are fulfilled in a timely manner.
In addition, CDRH launched this publicly available webpage to keep all stakeholders informed of the progress of each PAS. The webpage displays general information regarding each PAS, as well as the overall study status (based on protocol-driven timelines and the adequacy of the data) and the applicant's reporting status for each submission due.
Transit. Adolescent B (as adults) : 18-21 yrs,
Final Study Results
Actual Number of Patients Enrolled
Actual Number of Sites Enrolled
Patient Followup Rate
Follow-up rates were 95.2%, 87.4%, 85.3%, 83.7%, and 85.3% at years 1-5, respectively.
Final Safety Findings
There were six safety endpoints evaluated after the Alair treatment, and they were acceptable at
5 years follow-up. The Rates for Severe Exacerbation Event, for Respiratory Adverse Event (events/subject/year), for Emergency Room Visits for respiratory symptoms (events/subject/year), and for Hospitalizations for respiratory symptoms (events/subject/year) in each subsequent year (2 through 5) compared to year 1 post therapy (0.486, 2.0, 0.07, 0.039) were non- inferior and were sustained through year five. There was no increase in the above rates and Respiratory Serious Adverse Events over time. FEV1 did not deteriorate over 5 years. There were no structural changes in the airways based on the review of 93 High-resolution computed tomography (HRCT) pairs at Baseline and at Year 5.
Final Effectiveness Findings
The proportions of subjects (expressed in percentages)
experiencing one or more severe exacerbations in Years 1-5
after the Alair treatment were 30.9%,
23.6%, 34.0%, 36.5%, and 21.6%, respectively. The upper 95% confidence limit of the difference
between the subsequent 12-month proportions (for Years 2, 3, 4, and 5) compared to the first 12-month proportion remained less than the pre-specified non-inferiority margin of 20%. Therefore, the proportions are not significantly worse, i.e. the primary endpoint for the study has been met. Treatment effectiveness is durable out to five years.
Study Strengths and Weaknesses
The study cohort was originally randomized and treated. However, during the 5-year follow-up, it became
an open-label single-arm study, i.e. subjects became unblinded to treatment introducing a possible placebo effect. The subject population is predominately Caucasians (~80%), thus, the results may best represent the Caucasian population.