24-month data show back and leg pain scores are reduced with the Senza spinal cord stimulation system


Nevro Corp has announced that the 24-month results of a prospective European clinical study using Nevro’s Senza system delivering HF10 therapy were published in the journal Pain Medicine. The study was conducted in the UK and Belgium with 65 of the 72 implanted patients (90%) being available for data collection at two years.

This clinical study evaluated the long-term safety and efficacy of HF10 therapy in patients with difficult-to-treat chronic, retractable low-back and leg pain. At baseline, 86% of the patients included in the 24-month analysis had primary back pain and 79% had failed back surgery syndrome. After two years of HF10 therapy, the mean baseline back pain score of 8.4 out of 10 was reduced to 3.3 (p<0.001). The mean baseline leg pain score of 5.4 out of 10 was reduced to 2.3 (p<0.001). The mean dosage of oral morphine equivalents per patient decreased from 84mg/day to 27mg/day (p<0.001). Disability and sleep disturbances were also significantly reduced. The safety profile of HF10 therapy was comparable to traditional spinal cord stimulation in terms of type and rates of complications.

The Senza system is presently the subject of the SENZA-RCT pivotal study, a landmark prospective, randomised, controlled study in the USA to evaluate the safety and efficacy of Nevro’s Senza system in patients with chronic pain. The SENZA-RCT study is the first pivotal randomised, controlled trial in the history of spinal cord stimulation and the only randomised study with a head-to-head comparison of spinal cord stimulation systems. Nevro announced completion of enrolment in the study in March 2013, with 241 patients enrolled over a seven-month period at 11 leading pain centres across the USA. Patients were randomised to receive either the Senza system or a traditional low-frequency spinal cord stimulation system.

Nevro’s Senza system delivers HF10 therapy, a spinal cord stimulation therapy that provides electrical pulses to the spinal cord at a rate up to 10,000 per second (10 kHz), as compared to traditional low-frequency spinal cord stimulation therapy, which usually deliver the electrical pulses at less than 100 pulses per second for chronic back and leg pain. The electrical pulses are conveyed by small electrodes placed in the epidural space and connected to a compact battery-powered generator implanted under the skin. The Senza system utilises a rechargeable battery and has achieved a CE Mark labelling for a 10 year battery life.

The Senza system is authorised for sale in Europe and Australia and is supported by European data published in Pain Medicine and Neuromodulation: Technology at the Neural Interface. In the USA, the system is limited by federal law to investigational use only and is not available for sale.