Evaluation of Injectable Naloxone-Releasing Hydrogels

Local drug delivery challenges and innovations in spinal neurosurgery

The development of novel therapeutics in the field of spinal neurosurgery faces a litany of translational challenges. Achieving precise drug targeting within the confined spaces associated with the spinal cord, canal and vertebra requires the development of next generation delivery systems and devices. These must be capable of overcoming inherent barriers related to drug diffusion, whilst concurrently ensuring optimal drug distribution and retention. In this review, we provide an overview of the most recent advances in the therapeutic management of diseases and disorders affecting the spine, including systems and devices capable of releasing small molecules and biopharmaceuticals that help eliminate pain and restore the mechanical function and stability of the spine. We highlight material-based approaches and minimally invasive techniques that can be employed to provide control over drug release kinetics and improve retention. We also seek to explore how the newest advancements in nanotechnology, biomaterials, additive manufacturing technologies and imaging modalities can be employed in this translational pursuit. Finally, we discuss the landscape of clinical trials and recently approved products aimed at overcoming the complexities associated with drug delivery to the spine.

Nanotechnology-Enhanced Naloxone and Alternative Treatments for Opioid Addiction

Opioids are commonly prescribed to address intense, ongoing pain associated with cancer, as well as long-lasting noncancer-related pain when alternative methods have proven ineffective. Individuals who exhibit both chronic pain and misuse of opioids face a significant danger of experiencing adverse health outcomes and the potential loss of life related to opioid use. Thus, there is a current movement to prescribe naloxone to those considered high-risk for opioid overdose. Naloxone has been explored as an antidote to reverse acute respiratory depression. Conversely, naloxone can give rise to other problems, including hypertension and cardiac arrhythmias. Thus, the importance of nanotechnology-enabled drug delivery strategies and their role in mitigating naloxone side-effects are significant. In this review, we explore the latest advancements in nanotechnology-enabled naloxone and alternative methods for addressing the opioid crisis through the utilization of non-opioid natural alternatives for chronic pain management.

Antiviral fibrils of self-assembled peptides with tunable compositions

The lasting threat of viral pandemics necessitates the development of tailorable first-response antivirals with specific but adaptive architectures for treatment of novel viral infections. Here, such an antiviral platform has been developed based on a mixture of hetero-peptides self-assembled into functionalized β-sheets capable of specific multivalent binding to viral protein complexes. One domain of each hetero-peptide is designed to specifically bind to certain viral proteins, while another domain self-assembles into fibrils with epitope binding characteristics determined by the types of peptides and their molar fractions. The self-assembled fibrils maintain enhanced binding to viral protein complexes and retain high resilience to viral mutations. This method is experimentally and computationally tested using short peptides that specifically bind to Spike proteins of SARS-CoV-2. This platform is efficacious, inexpensive, and stable with excellent tolerability.

Covalently Loaded Naloxone Nanoparticles as a Long-Acting Medical Countermeasure to Opioid Poisoning

The mu opioid receptor antagonist naloxone has been a vital, long-standing countermeasure in the ongoing battle against opioid use disorders (OUD) and toxicity. However, due to its distinctive short elimination half-life, naloxone has shown diminished efficacy in cases of synthetic opioid poisoning as larger or repeated doses of the antidote have been required to achieve adequate reversal of severe respiratory depression and prevent episodes of renarcotization. This report describes the synthesis, characterization, and in vivo evaluation of a novel, nanoparticle-based naloxone formulation that provides extended protection against the toxic effects of the powerful synthetic opioid fentanyl. The strategy was predicated on a modified two-step protocol involving the synthesis and subsequent nanoprecipitation of a poly(lactic-co-glycolic acid) polymer scaffold bearing a covalently linked naloxone chain end (drug loading ∼7% w/w). Pharmacokinetic evaluation of the resulting covalently loaded naloxone nanoparticles (cNLX-NP) revealed an elimination half-life that was 34 times longer than high dose free naloxone (10 mg/kg) in male Sprague-Dawley rats. This enhancement was further demonstrated by cNLX-NP in subsequent in vivo studies affording protection against fentanyl-induced respiratory depression and antinociception for up to 48 h following a single intramuscular injection. These discoveries support further investigation of cNLX-NP as a potential therapeutic to reverse overdose and prevent renarcotization from fentanyl and its potent analogs.