The journal article “Stratification of patients based on the neuropathic pain symptom inventory (NPSI): development and validation of a new algorithm”, has been published ahead of print in the journal Pain. This article was authored by Didier Bouhassira, MD, Director of Research at the National Institute for Health and Medical Research (INSERM) in France, and was co-authored by Tools4Patient scientists Samuel Branders PhD, Alvaro Pereira PhD and Dominique Demolle, PhD.

Neuropathic pain can arise from varied etiologies and results in heterogeneous pain symptoms, and currently, less than 50% of patients achieve partial pain relief with recommended drug treatments. A personalized medicine approach, in which pain medications are tailored to individual patients, is attractive – yet there has historically been a lack of consensus on the most appropriate method by which to classify and optimally treat neuropathic patients.  

This study confirmed the presence of 3 clusters of patients (in a cohort of N=628 patients) based on the specific sensory characteristics of their pain as identified by the Neuropathic Pain Symptoms Inventory (NPSI). An algorithm was developed to assign each of these patients into one of three clusters with specific combinations of symptoms, i.e. primarily “pinpointed pain”, “evoked pain” or “deep pain” – that were largely not associated with the etiology of neuropathic pain.

The developed algorithm was then used to classify patients from a separate cohort (N=97 patients) to one of the three clusters, and their differential response to treatment with botulinum toxin A (BTX-A) was evaluated. Patients in two of the clusters (characterized by “evoked pain” and “deep pain”) responded to BTX-A more strongly than placebo, while patients in the “pinpointed pain” cluster did not respond to BTX-A.

These results suggest that the NPSI may be an easily administered, reliable tool to better predict specific patient response to pain treatments in neuropathic pain. “The categorize patients based on sensory phenotype is a great step toward the goal of customizing pain treatments to the specific patient,” claimed Dr. Didier Bouhassira.

“Using advanced mathematical approaches similar to those employed in this study can also enable clinical drug development”, indicates Dr. Alvaro Pereira, Tools4Patient’s CSO. “Tools4Patient is committed to our mission of developing predictive tools that de-risk clinical trials and improve decision making in drug development.”