Abstract
We propose to develop a broad acute/sub-acute opioid drug detoxifying treatment for
opioid overdose that can complement & compensate for the deficiencies in nalaxone,
using opioid-targeted biomimetic “nanosponges” that absorb overdosed opioids in the
body. (Note: if this proof-of-concept is successful here, the approach may be tailored to other
drugs-of-abuse.) Called “NarcoBondTM” these 100 nm diameter nanospheres are assembled
from a mixture of cholesterol & synthetic choline-based phospholipids that mimic the lipid bilayer
cell membranes. Its multifunctional surface displays an optimized milieu of human membrane
proteins isolated from: a) erythrocytes to increase half-life in peripheral blood & circulation, b)
neurons to increase binding affinity for opioid receptor, & c) purified Mu opioid receptors to bind
opioids in circulation. The NarcoBond's repertoire of native opioid receptors broadly binds &
captures opioids from microenvironmental niches of cells in tissues & will result in an
antagonistic pharmacological effect by rapidly reducing the concentration of the overdosed
opioid.
Significance. Every 15 min. in the US, a person dies after overdosing on opioids.1 Naloxone, an
opioid receptor antagonist, is, to date, the only life-saving treatment for opioid overdose based
on its ability to reverse respiratory depression acutely.3 Yet the pharmacodynamic actions of
naloxone last for a briefer period than all but the most short acting opioids;3-9 although the
elimination half life of naloxone is similar to that of morphine (60–90')9 it is redistributed away
from the brain more rapidly.3 Consequently, the patients may become renarcotised after
naloxone treatment due to the continued presence of opioids in peripheral blood. In full
development, NarcoBond offers a more broad alternative for cost effective & longer lasting
means to cleanse the peripheral blood of opioids, reducing the risk of renarcotisation, &
assisting in the life-saving reversal of overdose-induced respiratory depression. While
prompting acute withdrawal syndrome (AWS) is always a risk in rapid opioid receptor blockade,
without renarcotisation's acute risk of recurrent respiratory depression, clinicians will
have more time to intervene with gradual weaning protocols to avoid AWS. In addition,
NarcoBond's broad capability to mitigate against all opioids including highly potent synthetic
acrylfentanyl (i.e., “naloxone resistant” chemical threat agents), addresses unmet need(s) for
medical countermeasures in terrorism & hostage scenarios.8,11