Fast-Acting Sub-Perception Therapy (FAST) has demonstrated robust, profound pain relief with rapid (seconds to minutes) onset of analgesia in chronic pain patients implanted with Spinal Cord Stimulation (SCS) systems.1 Initial results have been corroborated at other centers.2 Sustained long-term improvement of up to 3 years has also been reported in an observational, real-world case-series.3 Recently published work suggests that FAST engages the surround inhibition mechanism of action, and computational modeling suggests that FAST activates dorsal column axons and inhibits dorsal horn projection neurons.4
The FAST study is a prospective, multi-center, single-arm study (with adaptive design) of patients implanted with SCS systems (WaveWriterTM Systems, Boston Scientific, Valencia, CA, USA) for chronic pain. The primary endpoint is based on the targeted pain responder rate (≥50% reduction) 3-months post-activation with no increase in average daily opioid medications. Secondary endpoints include (but are not limited to) patient satisfaction (Patient Global Impression of Change, PGIC) and other functional outcomes including disability (Oswestry Disability Index, ODI) and sleep. Key inclusion criteria include diagnosis of predominantly neuropathic pain of trunk and/or limbs for at least 6- months, and no back surgery within 6-months prior to screening.
The study successfully met its primary endpoint (p<0.0001) based on a prespecified cohort of 20 subjects. A 6.1-point reduction (p<0.0001) in mean low back pain score at 3 months was reported with a 95% responder rate (≥50% improvement in pain relief). A 31-point improvement in disability (ODI) and high patient satisfaction ratings (85% reported much improved or very much improved, PGIC) were found. At the FAST-SCS activation visit, FAST responders achieved maximum paresthesia-free pain relief within a mean of 5.4-minutes.
Preliminary results from this ongoing FAST prospective study suggests that profound, significant pain relief along with improvement in functional outcomes may be achieved in chronic pain patients with FAST therapy and additional SCS therapy options. With availability of multiple modalities in SCS systems, the capability for rapid onset of analgesia is particularly useful in evaluating what may be best suited for patients.
Significant pain relief and improvement in functional outcomes were reported in the FAST prospective study. These study results are consistent with published real-world experience that has assessed over 200 patients.5
1. Metzger CS, et al. A novel fast-acting sub-perception spinal cord stimulation therapy enables rapid onset of analgesia in patients with chronic pain. Expert Rev Med Devices 2021 Mar; 18(3): 299-306.
2. Ferro R, Pei Y, Jain R. Significant Pain Relief Using an SCS System Delivering Novel, Fast-Acting Sub-Perception Therapy [Abstract e-poster] Annual Meeting of the North American Neuromodulation Society, 2023.
3. Bayerl S, Paz Solis JF, Matis G, et al. Clinical Outcomes Using A New Fast Acting Sub Perception Therapy For Chronic Pain A Multicenter European Observational Real World Study [Abstract Poster 113]. Annual Meeting of the North American Neuromodulation Society, 2023.
4. Gilbert JE, Titus N, Zhang T, Esteller R, Grill WM. Surround Inhibition Mediates Pain Relief by Low Amplitude Spinal Cord Stimulation Modeling and Measurement. eNeuro 2022. Sep 22.ENEURO.0058-22.
5. Metzger C, Hammond MB, Ferro R, et al. Outcomes of a Large, Multicenter, Real-World Study using an SCS System Engaging Surround Inhibition [Abstract Poster 80]. Annual Meeting of the North American Neuromodulation Society, 2023.
1. To assess the FAST-SCS responder rate (defined as >50% pain relief when using FAST-SCS) among patients implanted with an SCS system
2. To assess the duration of onset of pain relief following FAST-SCS activation in FAST-SCS responders
3. To assess pain relief and functional outcomes in patients with an SCS system capable of FAST-SCS.