Product Info
Subperception Therapy - Clinical Summary
WaveWriter Alpha™ & WaveWriter Alpha™ Prime Systems Information for Prescribers
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Subperception Therapy - Clinical Summary
Determination of the safety and effectiveness of the Boston Scientic Spinal Cord Stimulator (SCS)
Systems for subperception therapy was based on a prospective, randomized, multicenter, crossover study
with the primary endpoint of responder rate (proportion of subjects with 50% or greater improvement in
overall pain) at 3 month post-device activation. A crossover design provided within-subject comparison
between the supra-perception and subperception settings.
The primary objective of this study was to demonstrate sustained clinically signicant pain relief in patients
with chronic pain when using the Boston Scientic SCS Systems at subperception amplitude.
Of the 197 subjects that provided consent to participate in the study, 136 were randomized to either
receive subperception followed by supra-perception settings or vice versa for 90 days post-activation. The
study cohort was comprised of subjects who have been treated successfully with paresthesia-inducing
stimulation for at least six months.
Efcacy Outcomes
The study successfully met its primary effectiveness endpoint, demonstrating that the proportion of overall
pain responders at 90 days post-activation with subperception settings is non-inferior compared to supra-
perception settings at a statistically signicant level (p < 0.001). The study also successfully demonstrated
non-inferiority in the Per Protocol group indicating the robustness of the study.
At the end of the crossover period, subjects were asked to choose between supra-perception and
subperception settings. Of the 70 subjects included in the primary effectiveness cohort, 53 subjects (76%)
chose subperception whereas only 17 (24%) chose supra-perception as their preferred treatment settings.
Additionally, 40 subjects (57%) preferred to keep both the stimulation treatments if given the option.
Safety Outcomes
A total of 27 adverse events were reported among 20 subjects across the entire study experience. Of
the 27 adverse events, 12 were serious adverse events (SAEs) and 15 nonserious adverse events.
All serious adverse events were unrelated to the study-device and/or study-procedure. There were no
unanticipated events.
Contraindications
Patients contraindicated for permanent Spinal Cord Stimulation (SCS) therapy are those who:
• are unable to operate the System
• have failed trial stimulation by failing to receive effective pain relief
• are poor surgical candidates
• are pregnant
Safety Information
WARNING: Unauthorized modication to the medical devices is prohibited. System integrity could
be compromised and harm or injury to the patient could occur if the medical devices are subjected to
unauthorized modication.