400 Section - Paving the way for a new local peripheral neuropathic pain treatment: Proof-of -concept clinical trial with AincobotulinmtoxinA (PaiNT)

Overall, 6-10% of adults are suffering from chronic pain with neuropathic features. Affected patients are significantly impacted in their physical, social, economic, and psychological well-being. Existing therapies are limited by insufficient treatment effect and side effects, resulting in a huge unmet medical need. First evidence with local Botulinum neurotoxin type A (BoNT/A) treatment in Peripheral Neuropathic Pain (PNP) has shown a superior number-needed-to-treat, compared to other pharmacological treatments.

Design:

Most previous clinical trials with BoNT/A were small, single centre, and with potential bias. This resulted in a weak GRADE recommendation for use as third line treatment in PNP patients. To fill the existing evidence gap, the ongoing phase 2 proof-of-concept clinical trial (PaiNT) investigates efficacy and safety of incobotulinumtoxinA (NT 201, Xeomin^®), a BoNT/A free from complexing proteins.

Results:

This randomised, double-blind, multicentre (31 sites, 6 countries), clinical trial is designed to include ≥120 adults with moderate to severe chronic PNP due to postherpetic neuralgia or peripheral nerve injury after surgery or mechanical trauma. Bedside Quantitative Sensory Testing (QST), aimed at patients’ phenotyping, is used for the first time in a BoNT/A clinical trial. Patients receive subcutaneous injections into the painful area with either incobotulinumtoxinA (≤300 units) or placebo and are followed-up for 20 weeks. The trial evaluations include changes in Average Daily Pain intensity, Neuropathic Pain Symptom Inventory, and safety endpoints.

Conclusion:

The large-scale PaiNT trial, investigating incobotulinumtoxinA in patients with PNP, may pave the way for a new local treatment of this burdensome condition.