Selective actin remodeling of sensory neurons for acute pain management

PROJECT SUMMARY
There is an urgent need for new approaches to treat acute human pain without the risk of Substance Use
Disorders (SUDs). The most effective approved pain pharmaceuticals, including narcotics and anesthetics, are
not neuron-specific and consequently suffer from off-target effects like addiction, inhibition of motor neurons, and
destruction of the surrounding tissues. When inflammation occurs, actin polymerization occurs in sensory
neurons, leading to the sensitization of purinergic receptors and abnormal pain behaviors. Targeted actin
remodeling could be an effective approach to reduce acute nociceptive pain, but there are no small-molecule
inhibitors with adequate specificity for sensory neurons that correctly modulate the cytoskeleton. Neurocarrus
proposes a new therapeutic approach for nociceptive pain based on an innovative engineered protein called N-
001 that selectively targets sensory neurons and acts only at the intra-cellular level inducing limited and
reversible depolymerization of the axon-associated actin cytoskeleton. This innovative biologic drug will provide
specificity towards sensory neurons while leveraging the features of the peripheral nervous system to eliminate
pain locally without interacting with the central nervous system.
Neurocarrus has completed an SBIR Phase I that has proven the feasibility of N-001 as a pain management
therapy. Results show that N-001 managed nociceptive post operative pain by efficiently reducing mechanical
allodynia and gait dysfunction in a mouse paw incision model relative to bupivacaine but with a significantly
longer duration of activity. N-001 retained efficacy for 3 days relative to only 6 hours for bupivacaine. N-001 was
also assessed as an anesthetic agent in a nerve block model where it also showed a significantly increased
duration of post operative pain management relative to bupivacaine. N-001’s mechanism of action was validated
in vivo, showing that it co-localizes with CGRP positive sensory neurons not motor neurons, and can be
quantitatively monitored using ADP-ribosylated actin as a measure of F to G actin neuronal content. Preliminary
ADME, toxicology and immunogenicity assays showed no adverse effects on organ function, provided
pharmacokinetic information, and non-neutralizing antidrug antibody formation only after multiple doses. These
data establish specific metrics for the use of N-001 as a post operative pain therapeutic thereby strengthening
the potential for use of N-001 in clinical pain management.
In this SBIR Phase II project, Neurocarrus will optimize the production and formulation of N-001 as well as the
development of manufacturing standards and controls for obtaining GLP-grade (Good Laboratory Practice) N-
001. GLP-grade N-001 will be used to perform pivotal pre-clinical studies to demonstrate its in vivo safety using
two preclinical animal models (C57BL/6 mice and Beagle dogs). GLP drug will also be used for efficacy studies
as a treatment for pain after peripheral joint surgery using a mouse distal tibial limb fracture model. The
completion of this project will support an investigational new drug filling (IND) enabling future clinical trials.

Grant Number: 2R44NS120337-02
NIH Institute/Center: NIH
Principal Investigator: Paul Blum