Funded Projects

Pain is a major problem for spinal cord injury (SCI) patients that tends to persist and even worsen with time. No treatments are currently available to consistently relieve pain in SCI patients. This study will investigate the feasibility of Epidural Electrical Stimulation (EES) using the Abbott Proclaim? SCS system with two electrodes to treat neuropathic pain in patients with thoracic spinal cord injury. In this double-blind, prospective, randomized clinical trial, patients with subacute, traumatic, complete thoracic SCIs with American Spinal Injury Association (ASIA) Impairment Scale A will be randomized to receive either ?EES on? (treatment intervention) or ?EES off? (control intervention) of the target regions for pain control (lead overlying the spinal cord anatomy corresponding with their pain distribution) and neurorestoration (lead overlying the conus medullaris) as an adjunct to physical therapy. This study will help determine whether EES can help patients with SCI neuropathic pain and have more widespread clinical applicability.

There is an unmet need for an effective parenteral/oral analgesic for acute post- operative pain management without the risks of opioid addiction. Salsalate, a dimer or salicylic acid, is currently available in oral dosage for the treatment of osteoarthritis and rheumatoid arthritis. Salsalate works at multiple levels to target multiple steps along the surgical pain pathway. Salsalate through its active metabolite, salicylic acid (SA), reduces NF-?B activation via IKK-kinase beta inhibition, and has no direct binding to cyclooxygenase 1 (Cox-1); therefore, does not affect function of platelets, resulting in a safer hematological and gastrointestinal safety profile. RH Nano proposes a plan for manufacturing and pre- clinical testing of parenteral M-salsalate in two animal models to assess the efficacy and safety in the treatment of acute postoperative pain management. In this proposal, the team will develop the optimal formulation under strict Chemistry Manufacturing and Control guidelines. In Phase II, the team proposes to conduct the pharmacokinetics and toxicology studies of M-salsalate in two species of animals (rodent and non-rodent). Additionally, the project will use an animal pain model for preclinical efficacy studies, and an in vivo Receptor Occupancy assay in animal brain tissues to assess the opioid sparing properties of M-salsalate. 

Voltage-gated sodium channels such as Nav1.7, Nav1.8, and Nav1.9 transmit pain signals in nerve fibers and are molecular targets for pain therapy. While Nav channels have been validated as pharmacological targets for the treatment of pain, available therapies are limited due to incomplete efficacy and significant side effects. Taking advantage of recent advances in structural biology and computational-based protein design, this project aims to develop antibodies to attach to Nav channels and freeze them in an inactive state. These antibodies can then be further developed as novel treatments for chronic pain.

Identification of new targets and mechanisms underlying chronic neuropathic pain is essential for the discovery of novel treatments and preventative tactics for better neuropathic pain management. A recent exploration of next-generation RNA sequencing identified a large, native, full-length long noncoding RNA (lncRNA) in mouse and human dorsal root ganglion (DRG). It was named as nerve injury-specific lncRNA (NIS-lncRNA), since its expression was found increased in injured DRGs, in response to peripheral nerve injury, but not in response to inflammation. Preliminary findings revealed that blocking the nerve injury-induced increases in DRG NIS-lncRNA levels ameliorated neuropathic pain. This project will validate NIS-lncRNA as a therapeutic target in animal models of neuropathic pain and in cell-based functional assays utilizing human DRG neurons. Completion of this proposal will advance neuropathic pain management and might provide a novel, non-opioid pain therapeutic target.

Neck pain is the fourth leading cause of disability and also a significant cause of cervicogenic headaches. Many of the currently available neck pain treatments are invasive with associated risks and complications, particularly because of the complex anatomy. Magnetic resonance guided focused ultrasound, a novel, completely noninvasive technique, can precisely target spinal facet joints to help ameliorate neck pain, potentially transforming the current practices. The goal of this study is to develop a cervical spine-specific device and demonstrate its safety and efficacy on targeting cervical sensory fibers and the third occipital nerve. The results of these studies will provide an understanding on how to best use this technology for chronic neck pain as well as a basis for translation into human use.

Neuropathic pain is characterized by neuronal hyperexcitability and spontaneous activity, properties associated with activity of hyperpolarization-activated, cyclic nucleotide-regulated (HCN1-4) channels, the source of the pacemaker current, Ih. Inhibition of HCN1-mediated Ih elicits marked antihyperalgesia in multiple animal models of neuropathic pain, including models for direct nerve injury and chemotherapy-induced peripheral neuropathy, and does so with little or no disruption to either normal pain processing or baseline behaviors and activities. The overall objective is to develop a peripherally restricted HCN1 inverse-agonist as a therapeutic for neuropathic pain. Researchers have generated a novel small molecule that combines an antihyperalgesic HCN1 inhibitor with a motif that controls distribution and membrane presentation and is a potential non-opioid antihyperalgesic treatment for peripheral neuropathic pain.

Chronic pain from tissue injury often stems from long-term changes in spinal cord circuits that change nerve sensation. Reversing these changes may provide better pain therapeutics. Previous work in animal models showed that activating G protein-coupled receptor 37 (GPR37) dampens nerve signal intensity after long-term stimulation and alleviates pain behavioral responses. This project aims to validate GPR37 in the spinal cord as a useful target for new treatments for neuropathic pain. The work will facilitate screening and identification of new molecules that activate GPR37, which can then be tested for efficacy and safety in further research in animal models of pain.

Most of the 200k Americans who undergo thoracotomy each year receive opiates to reduce postoperative pain because clinicians have few non-addictive, cost-effective choices to control the severe pain patients often experience in the first two weeks after surgery. Managing pain post-thoracotomy is critical to enable patients to take deep breaths and remove (via coughing) lung secretions that otherwise significantly increase risk of pneumonia and collapsed lung, hospital re-admission and morbidity. The most severe pain associated with thoracotomy is transmitted along the intercostal nerves, but no long-term analgesic or nerve block device exists that can provide safe and effective long-term reduction of pain. A reversible, patient-controlled, non- addictive, intercostal nerve block device would reduce suffering due to thoracotomy, broken ribs and herpes zoster. In this Phase I project, the team will develop a minimally invasive thermal nerve block device that can control nerve conduction by gently warming and cooling a short nerve segment between room temperature and warm water temperature. This novel approach is based on the discovery that warm and cool temperature mechanisms of nerve block are different and additive, enabling moderate-temperature nerve block by cycling neural tissues slightly above and below body temperature. Reversible thermal nerve blocks represent a completely new approach to managing pain.  

Taxanes are among the most effective chemotherapeutic agents and are frequently used in the treatment of early stage and metastatic breast cancer. However, they are known to produce a pain condition known as Chemotherapy-Induced Peripheral Neuropathic Pain (CIPNP). CIPNP is one of the primary reasons a patient receives a limited dose of taxane. No diagnostic tool exists to identify patients that will develop CIPNP in response to taxane therapy. Biomarker signatures associated with taxane-induced neuropathic pain will be developed to: 1) identify patients at risk for developing debilitating taxane neuropathic pain before chemotherapy is initiated; and 2) to identify patients already on treatment who are at risk of developing neuropathic pain and need dosing adjustments to prevent CIPNP symptoms. This biomarker signature will be used to detect CIPNP-susceptible patients early and personalize their taxane therapy to minimize CIPNP while optimizing the therapeutic taxane dosing.

We propose to develop a safe and effective nonopioid analgesic to treat neuropathic pain that targets an isoform of the voltage-gated sodium ion channel, NaV1.7. Voltage-gated sodium channels are involved in the transmission of nociceptive signals from their site of origin in the peripheral terminals of DRG neurons to the synaptic terminals in the dorsal horn. NaV1.7 is the most abundant tetrodotoxin-sensitive sodium channel in small diameter myelinated and unmyelinated afferents, where it has been shown to modulate excitability and set the threshold for action potentials. Development of systemic NaV1.7 inhibitors has been complicated by the challenge of achieving selectivity over other NaV isoforms expressed throughout the body. We have discovered a series of potent, state-independent NaV1.7 inhibitors that exhibit >1000-fold selectivity over other human isoforms. Work conducted under this program will support advancement of a lead candidate into clinical development as a therapeutic for neuropathic pain.

Effective treatments are elusive for the majority of patients with neuropathic pain. Reactive oxygen and nitrogen species (ROS/RNS) are involved in neuropathic pain, because they drive mitochondrial dysfunction, cytokine production, and neuronal hyperexcitability; therefore, stimulation of endogenous antioxidants is predicted to simultaneously resolve multiple neuropathic pain mechanisms. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that is a potential therapeutic target because it regulates the expression of a large number of endogenous antioxidant-related genes and can be activated with a single drug. This project will test the hypothesis that Nrf2 activation increases multiple endogenous antioxidants, therefore reversing neuropathic pain behaviors and counteracting neuropathic pain mechanisms that are driven by ROS/RNS and could provide an effective pain therapy, with minimal abuse/addictive potential.

There is a continued need to discover and validate new targets for potential therapeutic strategies for effective and safe treatment of pain. This project focuses on the protein metadherin, also known as astrocyte elevated gene-1 protein (AEG-1), as a possible new target for pain treatment. Preliminary studies have shown that mice genetically engineered to lack metadherin had significantly lower inflammation and chronic pain-related behaviors. This project aims to further validate AEG-1 as a pain target and test whether reducing levels in white blood cells called macrophages might work as a therapeutic strategy to reduce chronic inflammatory and/or neuropathic pain using an innovative nanoparticle approach to target specific cells.

Overreliance on opioids to treat chronic pain has been a contributor to the increase in individuals experiencing opioid addiction. This project aims to develop an innovative treatment approach for chronic pain that targets the cannabinoid receptor 1 (CB1R) to block the sensation of pain. The approach seeks to identify molecules that interact with a different part of the CBR1 receptor than do endocannabinoids and the primary active component of cannabis, tetrahydrocannabinol. Molecules that bind to and activate CBR1 in this different way (at an “allosteric” site) may produce nerve signaling that might differ from the effects of cannabis and endocannabinoids. This redirection of signaling pathways could help eliminate the risk of adverse effects observed with natural cannabinoids and other CBR1-binding molecules. The goal of this project is to identify a CB1R allosteric molecule, conduct studies toward obtaining federal permission to develop it as a medication, and to test it in a Phase I clinical study.