An FDA advisory committee panel yesterday voted against approving BTG‘s PneumRX’s Elevair endobronchial coil system intended for treating patients with severe emphysema.
The panel voted 7 to 5 in favor of the device’s safety, but 8 to 3 that the benefits do not outweigh the risks, and 5 to 7 that the device was effective for use with patients in its proposed indications.
The Elevair device is a nitinol endobronchial coil intended to be deployed bronchoscopically to reduce lung volume in patients with severe emphysema. The company submitted an application for premarket approval with the FDA, backed by clinical evidence from a trial of the device.
The assessor blinded, prospective, randomized, multi-center Renew trial examined the use of the device over a year, and included four years of additional follow-up visits with 315 subjects.
Results from the trial indicated a statistically significant improvement at 12 months in its primary effectiveness endpoint, but there was a “loss of treatment effect beyond 12 month,” according to the FDA.
In its pivotal trial, which examined the system in 114 patients, of the 81% patients who completed the 2 year and 39% that completed the 3-year visit, results from the six minute walk test showed a decline of 17.2 meters and 39.3 meters, respectively. Forced expiratory volume in one second results were also similar to baseline at 2 and 3 years, the FDA said.
The most common adverse events in the trials in both the treatment and control groups were COPD exacerbation at 69.7% and 58% of subjects, respectively, while the treatment arm experienced a 58.7% rate of hemoptysis. Patients treated with the elevator reported a 32.9% rate of lower respiratory tract infections, versus 8.9% in the control arm, an 11.6% rate of pneumothorax versus 0.6% in the control arm and a 21.3% rate of dyspnea versus 7.6% in the control arm.
Total device related serious adverse events were reported to occur in 45.8% of patients in the treatment arm, though mortality rates in both arms were comparable, according to the FDA release.
There was no noted decrease in COPD related adverse events, and an increased health care resource utilization at 12 months post-treatment, the FDA said.
“The single, prospective, multicenter randomized trial supporting this application demonstrated a statistically significant improvement in 6MWT, FEV1 and SGRQ at 12 months; however, the clinical meaningfulness of the observed changes in these endpoints is uncertain. Data regarding maintenance pulmonary rehabilitation were not collected as part of the study. Therefore, the effect of this confounding factor on the study results is unknown. The SGRQ results need to be interpreted with caution since there was no sham blinded arm. In addition, there were more COPD-related AEs in the treatment group compared controls, which did not correlate with the improvement observed in the SGRQ results. Moreover, there are significant risks associated with the coil treatment and the subsequent single-arm crossover study of the control patients did not replicate the results of the treatment arm during the randomized portion of the pivotal study,” the FDA wrote in its panel briefing.
BTG said it plans to continue to work with the FDA as it reviews the PMA application for Elevair, which it hopes will conclude in late summer this year, according to a press release.
