The Food and Drug Administration has approved the first high-frequency spinal cord stimulation (SCS) therapy for treating painful diabetic neuropathy (PDN).
The approval is specific for the treatment of chronic pain associated with PDN using the Nevro’s Senza System with 10 kHz stimulation. It is intended for patients whose pain is refractory to, or who can’t tolerate, conventional medical treatment. According to the company, there are currently about 2.3 million individuals with refractory PDN in the United States.
The 10 kHz device, called HFX, involves minimally invasive epidural implantation of the stimulator device, which delivers mild electrical impulses to the nerves to interrupt pain signal to the brain. Such spinal cord stimulation “is a straightforward, well-established treatment for chronic pain that’s been used for over 30 years,” according to the company, although this is the first approval of the modality specifically for PDN.
Asked to comment, Rodica Pop-Busui MD, PhD, the Larry D. Soderquist Professor in Diabetes at the University of Michigan, Ann Arbor, said that “the approval of the Nevro 10kHz high-frequency spinal cord stimulation to treat pain associated with diabetic neuropathy has the potential for benefit for many patients with diabetes and painful diabetic peripheral neuropathy.”
She noted that, “although there are several other pharmacological agents that currently carry the FDA approval for PDN, this is a condition that is notoriously difficult to treat, particularly when taking into account the actual number needed to treat with a specific agent to achieve a clinically meaningful pain reduction, as well as the spectrum of side effects and drug-drug interactions in a patient population that require many other additional agents to manage diabetes and comorbidities on a daily basis. Thus, this new therapeutic approach besides effective pain reduction has the additional benefit of bypassing drug interactions.” Dr. Pop-Busui was the lead author on the American Diabetes Association’s 2017 position statement on diabetic neuropathy.
She also cautioned, on the other hand, that “it is not very clear yet how easy it will be for all eligible patients to have access to this technology, what will be the actual costs, the insurance coverage, or the acceptance by patients across various sociodemographic backgrounds from the at-large clinical care. However, given the challenges we encounter to treat diabetic neuropathy and particularly the pain associated with it, it is quite encouraging to see that the tools available to help our patients are now broader.”
Both 6-and 12-month results show benefit
The FDA approval was based on 6-month data from a prospective, multicenter, open-label randomized clinical trial published in JAMA Neurology.
Use of the 10-kHz SCS device was compared with conventional treatment alone in 216 patients with PDN refractory to gabapentinoids and at least one other analgesic class and lower limb pain intensity of 5 cm or more on a 10-cm visual analog scale.
The primary endpoint, percentage of participants reporting 50% pain relief or more without worsening of baseline neurologic deficits at 3 months, was met by 5 of 94 (5%) patients in the conventional group, compared with 75 of 95 (79%) with the 10-kHz SCS plus conventional treatment (P < .001).
Infections requiring device explant occurred in two patients in the 10-kHz SCS group (2%).
At 12 months, those in the original SCS group plus 86% of subjects given the option to cross over from the conventional treatment group showed “clear and sustained” benefits of the 10-kHz SCS with regard to lower-limb pain, pain interference with daily living, sleep quality, and activity, Erika Petersen, MD, director of the section of functional and restorative neurosurgery at the University of Arkansas for Medical Sciences, Little Rock , reported at the 2021 annual scientific sessions of the ADA.
Infection was the most common study-related adverse event, affecting 8 of 154 patients with the SCS implants (5.2%). Three resolved with conservative treatment and five (3.2%) required removal of the device.
The patients will be followed for a total of 24 months.
Commercial launch of HFX in the United States will begin immediately, the company said.
Dr. Pop-Busui has received consultant fees in the last 12 months from Averitas Pharma, Boehringer Ingelheim, Nevro, and Novo Nordisk. Dr. Petersen has financial relationships with Nevro, Medtronic, and several other neuromodulator makers.