麻豆传媒

SAN DIEGO -- Pain relief from a spinal cord stimulation device for diabetic neuropathy was durable long-term, according to 18-month results from the SENZA-PDN trial.

When added to conventional medication management, patients treated with 10-kHz of high frequency spinal cord stimulation using the implantable Senza System saw an average 73% reduction in pain, said Christian Nasr, MD, of the Cleveland Clinic in Ohio.

By month 18, 85% (121 of 142) of patients were considered "responders" to treatment and 54% were even considered "profound responders" -- defined as achieving 80% or greater pain relief, Nasr said at the American Association of Clinical Endocrinology (AACE) annual meeting.

Patients also experienced reductions in dysesthesias. This included patient-reported improvements in numbness, burning, tingling, and cold feeling in the feet. Though not measured at the 18-month follow-up, 63.4% of patients saw improvements in motor, sensory, or reflex functioning without a deterioration at month 12.

Beyond pain relief, treated patients also gained in quality of life: a 64% average reduction in pain interference, plus a 70% improvement in sleep quality.

Throughout the trial, there was no change noted in BMI or HbA1c.

The number needed to treat was only 1.3, which Nasr's group noted is far lower than what's seen with medication-related treatments currently available for painful diabetic neuropathy. For example, found a number needed to treat of 3.6 to 7.7 for medications including gabapentin, pregabalin, serotonin and norepinephrine reuptake inhibitors, tricyclic antidepressants, and oral opioids.

In comparison, other trials assessing low-frequency spinal cord simulation devices had seen generally lower responder rates, ranging between to , than in SENZA-PDN.

The device was FDA approved in July 2021, making it the first spinal cord stimulation device for painful diabetic neuropathy. Underpinning this approval was 6-month trial data, presented at last year's AACE virtual meeting, and published in Diabetes Care.

The device works by delivering high-frequency stimulation -- 10 kHz frequency, 30 μs pulse width delivered via bipole, with an amplitude range of 0.5 to 3.5 mA -- directly to the spinal cord. Two percutaneous leads are placed epidurally and connected to the pulse generator. Stimulation can be adjusted according to patient feedback.

In the first 6-month trial, which compared the device to conventional medical management alone, participants saw a 76.3% reduction in pain with the simulation, with more than 85% of patients considered responders to treatment. After this 6-month point, participants in the conventional treatment group were offered the option of getting the device implanted -- an opportunity that 93% of eligible patients accepted.

"[This shows] a substantial unmet need for this patient population," Nasr pointed out. "We all know that about 60% of patients will not continue on their medication because of side effects or because they see no results."

The 18-center trial included patients suffering from painful diabetic neuropathy for at least a year that was refractory to conservative treatments. All 216 participants had a BMI under 45 and an HbA1c under 10%. The average age was 61, and the majority of participants were white males. Nearly all had type 2 diabetes, but a few participants had type 1 diabetes.

At baseline, patients had lower limb pain of 5 cm or more on the Visual Analogue Scale. Neurological functioning was measured via a diabetic foot exam with Semmes-Weinstein 10-g monofilament and 40-g pinprick tests.

A total of 95% of implanted patients remained in the trial for long-term follow-up, with only six explants of the device. There were no stimulation-related neurological deficits, and no devices were explanted because of loss of efficacy. There were eight (5.2%) procedure-related infections that occurred, three of which resolved with antibiotics and five of which required explanation.

Nasr said his group will continue to follow these patients for the next 6 months to get a total of 24-month data.

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