Clinical evaluation of ThecaFlex DRx, a novel implantable catheter-port for intrathecal nusinersen delivery in spinal muscular atrophy: Initial results from the PIERRE-IDE study.

BACKGROUND

Administration of Nusinersen requires repeated lumbar intrathecal access, posing challenges for patients with Spinal Muscular Atrophy (SMA). A purpose-built system may streamline drug delivery.

OBJECTIVE

To assess the feasibility and safety of ThecaFlex DRx for intrathecal Nusinersen dosing.

METHODS

We present initial results of a prospective, multicenter investigational device exemption (IDE) study. Patients with SMA who had an indication for intrathecal Nusinersen were enrolled. Primary outcomes were successful system implantation and postoperative infusion. Prespecified safety outcomes consisted of adverse events adjudicated for severity and device or procedure relatedness.

RESULTS

Twenty-five subjects underwent device implantation. Median age at implantation was 13.8 years (IQR 10.0-18.0), and 52% were female. Subjects included individuals with SMA types I (16%), II (64%), and III (20%). Implantation was successful in all cases. At the interim data cutoff, median follow-up was 230 days (IQR 76.0-369.0) at which point 23 subjects (92%) had successfully received Nusinersen infusions. Ten patients reached one year of follow-up, and all of them maintained a functional device at this visit. Sixty adverse events occurred in 19 subjects, with 12 events (20%) adjudicated as serious adverse events that were most commonly wound-related or respiratory. At one year, the estimated probability of remaining free from device action was 86.2% (95% CI 0.73-1.00), with two devices requiring explantation due to wound dehiscence and access difficulties, respectively.

CONCLUSIONS

This interim report supports the feasibility of ThecaFlex DRx for Nusinersen administration, with long-term durability and effectiveness to be defined with longer follow-up.For more information about the PIERRE study (NCT05866419), visit: https://www.

CLINICALTRIALS: gov/study/NCT05866419.