Funded Projects

Patients with severe, intractable chronic pain primarily receive treatment with opioids, and non-opioid treatment options are urgently needed. These patients may be candidates for treatment using other types of pain medications administered via intrathecal injection—that is, injection directly into the fluid-filled space between the membranes surrounding the brain and spinal cord. Intrathecal injection requires much lower medication doses than systemic administration. Centrexion Therapeutics Corporation seeks to develop CNTX-3100, a highly selective and highly potent novel small molecule that activates the nociception receptor (NOPr), for intrathecal administration using a pump approved by the U.S. Food and Drug Administration. In animal studies, such NOPr agonists had powerful analgesic effects when delivered directly to the spinal cord by intrathecal administration. CNTX-3100 has ideal properties for intrathecal delivery and in animal studies provided pain relief and a safety profile that was superior to intrathecally administered morphine. This project will scale up the drug, develop a formulation that ensures a stable product for intrathecal delivery, and conduct preclinical toxicity studies to prepare for a Phase 1 clinical trial.

Knee osteoarthritis is one of the leading causes of disability worldwide, particularly among older adults. Despite multiple guidelines for care, most patients do not receive adequate treatment, and about 30% are prescribed long-term opioids. This award will be used to recruit and support an early career faculty member from a group underrepresented in biomedicine. This research, part of the Pain Management Effectiveness Research Network will evaluate conservative and more aggressive treatments for knee osteoarthritis and determine which individual-level factors contribute to treatment outcomes.

The NIH Back Pain Consortium (BACPAC) Research Program brings together leading centers with expertise in studying and treating chronic low back pain to advance understanding of the mechanisms that underlie the condition and to identify novel treatment strategies. BACPAC is undertaking a multisite precision medicine clinical trial taking into account patient-specific information to understand which patients with chronic low back pain respond best to various nonopioid, evidence-based treatments. The trial seeks to enroll a racially, ethnically, and socioeconomically diverse patient population to ensure that the results are applicable to all Americans with chronic low back pain. This project aims to develop comprehensive recruitment and retention plans for study sites that can recruit from historically underrepresented populations in clinical research (e.g., Black and Hispanic populations) and to provide dedicated financial resources to engage patients from these populations using tailored, culturally appropriate strategies.

Cholecystokinin B receptor (CCKBR) is a molecule found in the brain that helps regulate anxiety and depression but also influences the development of tolerance to opioids. CCKBR levels are also increased in models of nerve injury-induced (neuropathic) pain. Therefore, targeting CCKBR may offer a new approach to treating neuropathic pain and the associated anxiety and depression. Researchers have developed mouse antibodies that can inactivate CCKBR. However, to be usable in humans without causing an immune response, these antibodies need to be modified to include more human sequences. This project will use a fragment of the CCKBR antibody, modify it with the addition of human antibody sequences, and then select the clones that bind most strongly and specifically to human CCKBR. These will then be tested in cell and animal models of neuropathic pain to identify the most promising candidates for further evaluation in humans.

People with diabetes are at risk for painful diabetic peripheral neuropathy. This pain may be experienced as burning, aching, hypersensitivity to touch, or simply as pain, and there are no currently FDA-approved medications that reduce its symptoms. This phase 2 clinical trial, through the EPPIC-NET program, will test a potential new treatment for painful diabetic peripheral neuropathy. The molecule, NRD135S.E1, is a lab-made version of a natural substance traditionally used to brew tea to treat a variety of indications, including pain, in a village in Siberia. In clinical studies, NRD135S.E1 was well tolerated by patients and showed clinically relevant pain relief. Testing within EPPIC-Net will use a master protocol, an innovative study design in which multiple treatments can be tested at the same time with fewer research participants.

Chronic overlapping pain conditions represent up to half of all chronic pain cases and can be more debilitating than other forms of chronic pain. These conditions include but are not limited to the following: temporomandibular disorders, fibromyalgia, irritable bowel syndrome, vulvodynia, interstitial cystitis/painful bladder syndrome, painful endometriosis, chronic tension type headache, migraine headache, chronic low back pain, and chronic fatigue syndrome. Common neurobiological mechanisms have been suspected to account for the overlap between these conditions, but until recently it has been difficult to efficiently classify each condition within individual patients. A digital classification tool for clinicians has been developed for this purpose, but access to the tool remains limited. Here we propose converting this chronic overlapping pain conditions classification tool into a common web-based application format.

People with diabetes are at risk for painful diabetic peripheral neuropathy. This pain may be experienced as burning, aching, hypersensitivity to touch, or simply as pain, and there are no currently FDA-approved medications that reduce its symptoms. This phase 2 clinical trial, through the EPPIC-NET program, will test a potential new treatment for painful diabetic peripheral neuropathy. The treatment, WST-057 (topical pirenzepine 4%), is a molecule that was developed in the 1980s and marketed throughout Europe and Asia in an oral form to treat gastric ulcers. Studies show that this type of molecule can increase the density of certain nerve fibers, which has been linked with improve patient-reported outcome measures for painful diabetic peripheral neuropathy.

Epidural/spinal administration of analgesics such as opioids, ziconotide and local anesthetics have profound efficacy in some of the most intractable pain conditions such as severe neuropathic pain after failed back surgery, cancer pain and post-operative pain after major abdominal/thoracic surgeries. Contulakin G (CGX) is a snail venom derived peptide that has homology with mammalian neurotensin and was shown to be safe in humans in preliminary studies. A small pilot study demonstrated CGX?s analgesic effect in some patients with spinal cord injury-associated pain. Preliminary findings from mechanistic studies in rodents identified neurotensin receptor 2 (NTSR2) as the mediator for analgesic effects of CGX. This project aims to validate spinal NTSR2 as an analgesic target utilizing three species (rat, mice and human), and two pain models (neuropathic pain and post-surgical pain). The project will utilize pharmacological and gene editing tools such as CRISPR-Cas9 and will include assessment of both sensory and affective measures of pain. A two-site parallel confirmation study is designed based on multisite clinical trials to further authenticate spinal NTSR2 as an analgesic target. Successful completion of this project could lead to the development of a non-opioid spinal analgesic that has high translational potential.

Pain associated with surgery is experienced by millions of patients every year. Although post-surgical pain usually resolves as the surgical site heals, up to half of the patients develop chronic pain after surgery. Opioids remain the mainstay treatment for post-surgical pain which are fraught with serious side-effects and abuse liabilities. The endogenous mechanism that leads to the resolution of post-surgical pain remain unclear, specifically the effects of surgery on the metabolism of sensory neurons and how those changes influence the resolution of post-surgical pain are not known. Preliminary findings suggest that surgical trauma suppresses pyruvate oxidation while increased glutamine catabolism was associated with the resolution of post-surgical pain. This project will test the hypothesis that tissue incision and surgery disrupt the expression of the glutamine transporter ASCT2, which then prevents the resolution of post-incisional pain and aims to validate ASCT2 as a therapeutic target. This project will also employ pharmacological, genetic and animal pain model studies test a novel RNA expression-based strategy to enhance ASCT2 expression in DRG sensory neurons and alleviate postoperative pain in animal model systems. Successful completion of this project would validate ASCT2 as a novel endogenous non-opioid and non-addictive mechanism-based target for the resolution of postoperative pain.

A key marker of inflammation in Osteoarthritis (OA) is accompanied by significantly increased sensory innervation within the diseased joint. This study aims to validate the hypothesis that defective bone resorbing cells are responsible for the enlarged bone cavity, giving rise to the inflammatory marker causing further increases in levels sensory innervation and resulting in increased OA pain perception.

As many as 64% of patients with Temporomandibular Joint Disorders (TMJDs) report symptoms consistent with Irritable Bowel Syndrome (IBS). However the underlying connection between these comorbid conditions is unclear and treatment options are poor. As such, pain management for these Chronic Overlapping Pain Conditions (COPCs) is a challenge for physicians and patients. This project will determine whether the convergence of pain from different peripheral tissues and perceived stress occurs in the brain and elicits a change in central neural processing of painful stimuli. This project will identify and validate specific lipids, enzymes and metabolic pathways that change expression in the brain during the transition from acute to chronic overlapping pain that can be therapeutically targeted to treat COPCs. Multi-disciplinary approaches will be used to combine brain imaging, visualization of spatial distribution of molecules, genetics, pharmacological and behavioral research techniques.

Currently, there are no adequate therapies for abdominal pain in patients with Irritable Bowel Syndrome (IBS), a gastrointestinal disorder affecting 14-20% of the US population. More than 40% of IBS patients regularly use opioid narcotics. An alternative treatment for IBS that has been shown to be an effective pain management strategy is electroacupuncture. However its drawbacks include infrequent administration, unclear mechanistic understanding, and lack of methodology optimization. This study will use a noninvasive method of transcutaneous electrical acustimulation (TEA) by replacing needles with surface electrodes and testing acupoints that target peripheral nerves. Based on prior mechanistic and clinical studies, two stimulation parameters and effective acupoints will be tested. In the UG3 phase, the TEA device and a cell phone app will be optimized for use in IBS abdominal pain, and an acute clinical study will determine the best stimulation locations and parameters. During the UH3 phase, an early feasibility clinical study will be performed in 160 IBS patients in treating abdominal pain. Participants will self-administer the therapy at home/work and will be randomized across four treatment groups to determine the therapeutic potential of the TEA system.