Has it really been three years since the launch of Neuros Medical’s QUEST study? Not quite, but almost: The high-profile investigation got rolling in the fall of 2021. Last month, the first published data from that closely watched research finally appeared in the Journal of Pain Research, and it’s largely encouraging.
We’ll get to those conclusions in a second, but first a quick refresher about why the QUEST study has garnered so much attention. The exercise is a clinical trial of Neuros’s high-frequency nerve block system, Altius, and it’s noteworthy for its combination of size and rigorous methodology. Re the former, QUEST involved an unusually large and diverse sample of 180 patients from across the United States, over an unusually long 90-day period. All participants are unilateral lower-limb amputees who are experiencing chronic post-amputation pain (including phantom limb pain). As for methodology, QUEST employed a randomized, double-blind design, the most rigorous type of clinical trial. The application of this methodology on such a large research population over such a long, ongoing duration makes QUEST uncommonly robust among amputee pain management studies.
Altius falls within a category of pain treatment known as peripheral nerve stimulation, or PNS. It interrupts pain signals from the residual limb by delivering bioelectric impulses directly to the nervous system via specialized implants that wrap around individual nerve fibers (primarily the sciatic nerve, in the case of lower-limb amputees). Patients can exercise some control over the Altius system via a handheld device.
So does the thing work? Based on the large body of data from QUEST, the answer seems to be yes.
After being implanted with the Altius device, the study subjects recorded their daily pain experiences over three months. Upon activating the PNS system, they logged their pain levels at 30- and 120-minute intervals. The study was randomized because subjects could never be sure if the system was actually operating—by design, half of them were outfitted with “active-sham” devices that didn’t actually do anything. Researchers thus obtained a fairly objective picture of whether, and to what extent, Altius relieved patients’ pain.
At the 30-minute interval, about one-fourth of subjects with active Altius devices experienced a positive response (defined as 50 percent or greater reduction in pain), versus only 7 percent of those with sham devices. At the 120-minute interval, nearly half of subjects in the active-device group achieved a positive response, versus 22 percent of those in the sham-device cohort.
Moreover, when comparing the patients who reported a positive response in both groups, those in the active-device group exhibited a greater degree of pain reduction than the sham-devicers. The former averaged a 2.3-point decrease (on a scale of 10) in pain levels, versus a 1.3-point decrease in the latter group. The active-device users also used fewer opioid pain pills than the shammers, although this effect did not rise to the level of statistical significance.
The study’s principal investigator, Leonardo Kapural, said in a press release: “We have never seen a study of this magnitude and rigor in this patient population. The data demonstrated clear and lasting benefit of treatment for pain reduction and functional outcomes at three months, creating great optimism for the long-term study results. These findings represent a significant advancement for an at-risk and underserved patient population in desperate need of reliable and effective treatment.”
Additional results gathered over an even longer period (a full year) are due to be published later this year. Final FDA approval is still necessary before the device can be deployed commercially Get more information about Altius at neurosmedical.com/about/the-altius-system.
