Funded Projects

Chemotherapy-induced peripheral neuropathy (CIPN) is detected in 64% of cancer patients during all phases of cancer. CIPN can result in chemotherapy dose reduction or discontinuation, and can also have long-term effects on the quality of life. Taxanes (like Paclitaxel) may cause structural damage to peripheral nerves, resulting in aberrant somatosensory processing in the peripheral and/or central nervous system. Dorsal root ganglia (DRG) sensory neurons as well as neuronal cells in the spinal cord are key sites in which chemotherapy induced neurotoxicity occurs. T-type Ca2+ channels are critical determinants of increased neuronal excitability and neurotransmission accompanying persistent neuropathic pain. Though Cav3.2 has been targeted clinically with small molecule antagonists, no drugs targeting these channels have advanced to phase II human clinical trials. This proposal aims to explore multicomponent reaction products, for the rapid identification of potent and selective T-type Ca2+ channel antagonists. The work proposed here is the first step in developing non-opioid pain treatments for CIPN. The team anticipates success against paclitaxel-induced chronic pain will translate into other chronic pain types as well, but CIPN provides focus for early stage proof-of-concept.

This project will use state-of-the-art technologies to analyze individual cells to characterize how human pain receptors communicate pain between the human dorsal root ganglia and the brain – including how the signals vary across diverse populations. This research will generate useful, high-quality human data about pain for further analysis and re-use by other scientific teams, toward identifying and prioritizing novel therapeutic targets for pain.

Natural products, which are substances found in nature and made by living organisms, have been used in the past as good sources for developing new medications. Natural products isolated from marine bacteria that attach to the pain-signaling protein sigma-2 receptor (also known as transmembrane protein 97 [TMEM97]), may serve as a starting point to create new, non-opioid pain medications. This project will use chemistry and biology approaches to refine such natural products as a treatment for neuropathic pain.

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.

Chronic low back pain affects millions of people in the United States, resulting in high medical costs and lost productivity. New opioid-free treatments are needed to help people with chronic low back pain, but not all people respond equally to a given approach. IMPACT aims to use machine learning to analyze data such as physical activity, sleep, emotions, and pain levels and identify markers that can help predict how effective a mindfulness-based treatment approach (Mindfulness-Based Stress Reduction) can be for people with chronic low back pain.

Head and neck cancer is particularly susceptible to nociceptive and neuropathic pains because it is dense with sensitive anatomic structures and richly innervated. Transcranial magnetic resonance imaging–guided focused ultrasound (FUS) is a new stereotactic modality capable of delivering high-intensity energy through the intact human skull with submillimeter precision. This clinical trial will target the spinothalamic and spinoreticular pain circuits by unilateral FUS mesencephalotomy, an effective procedure for cancer pain but limited by the accuracy of its era. The primary aim is to assess the safety and preliminary effectiveness in six head and neck cancer patients with opioid-resistant pain. Researchers will investigate the potential mechanism of pain relief as the mesencephalotomy target involves the confluence of the ascending and descending pain systems. Aims 2 and 3 will investigate these systems with electrophysiology specific for the spinothalamic tract and carfentenil positron emission tomography imaging that measures the brain’s endogenous opioids.

Many chronic pain conditions are dependent upon activity of the sympathetic nervous system. Sympathetic blockade is used clinically in chronic pain conditions, but the clinical and preclinical evidence for this practice is incomplete. We propose that certain pathological pain conditions require intact sympathetic innervation of the sensory nervous system at the level of the dorsal root ganglion (DRG) and that release of sympathetic transmitters enhances local inflammation and leads to pain. Our preliminary data show large, rapid, and long-lasting reduction of pain behaviors and inflammatory responses following a"microsympathectomy" (mSYMPX) in both neuropathic and inflammatory pain models. Our aims are to: 1) characterize the effects of mSYMPX on pain and on local inflammation in the DRG; 2) explore the molecular mechanisms for sympathetic regulation of inflammatory responses in the DRG; and 3) assess the functional role of sympathetic transmitters in the sympathetically mediated inflammatory responses in the DRG.

Complex regional pain syndrome is a difficult-to-treat chronic condition that causes excess and prolonged pain and inflammation after injury to an arm or leg and includes damage to skin of affected limbs. Although it is known that aberrant immune system function plays a role in this condition, the details remain unclear about how this occurs – in particular, through the adaptive immune system that relies on specialized immune cells and antibodies to protect the body from harm.  This project will study the role of certain immune cells (T cells) that circulate throughout the body or reside in bone using both rat or human bone samples from patients with complex regional pain syndrome.

Oral cancer pain is debilitating and difficult to treat, in part because even the most effective available pain remedies are limited by side effects. Opioid-based pain medications have several side effects including dependence and tolerance, in which the body gets used to a medicine so that either more medicine is needed or different medicine is needed. Another side effect is hyperalgesia, in which people taking opioids become more sensitive to certain painful stimuli and may misuse the drugs and risk addiction. This project will evaluate lab-made versions of cannabinoid molecules known to block pain signals in nerve cells, but which cannot enter the brain to cause neurological side effects. The research aims to advance promising versions of the molecules to testing in human research participants.

Recent studies have reported that neuropathic pain involves changes in the central nervous system that are linked to necroptosis (programmed necrotic cell death) and release of cellular components that create neuroinflammation. Necroptosis is a type of necrotic cell death affected by the protein receptor-interacting serine/threonine-protein kinase 1 (RIPK1 or RIP1). Preliminary studies also indicate that pain increases levels of RIPK1 in key brain regions implicated in pain processing. This project aims to further validate RIPK1 as a target for neuropathic pain using a newly developed positron emission tomography imaging approach. The work will pave the way for new brain-penetrant RIPK1 inhibitors as a safe, effective, and nonaddictive treatment approach for neuropathic pain.

The Data Coordinating Center (DCC) of the Early Phase Pain Investigation Clinical Network (EPPIC-Net) will be the data and biospecimen manager for pain research within the HEAL Partnership. As such, it will host, manage, standardize, curate, and provide a sharing platform for data and biospecimens for HEAL initiatives, such as the Acute to Chronic Pain Signatures initiative and the BACPAC, in addition to EPPIC-Net studies. The DCC will develop and maintain a databank for depositing data, will link these data with a repository for biological samples, and will create a platform for teams to work together to analyze and interpret data. Further, the DCC will provide leadership in the statistical design and analysis of EPPIC-Net studies and will deploy advanced systems and processes for data collection, management, quality assurance, and reporting. The DCC will create, sustain, and continually advance a robust organization for the rapid design, implementation, and performance of high-quality rigorous Phase II clinical trials to test promising therapeutics for pain.

Disruptions in make-up of the microbiome are associated with disorders characterized by chronic pain and inflammation, such as rheumatoid arthritis and fibromyalgia. The gut microbiome has immune and metabolic effects, and human gut-derived bacteria may be a source of novel, safe, and non-addictive pain treatments. However, connections between gut and pain signals, known as the “gut–pain axis,” are still poorly understood. This study aims to identify human-gut-native bacteria that i) interact with known pain targets in lab studies, ii) test their activity and analgesic/anti-inflammatory potential in an animal model, and iii) develop a computational approach to predict microbial-genetic effects on pain signals.

The proposed Fast Track SBIR effort will develop and validate the reliable, low-cost KnowPain instrument. KnowPain will objectively and quantitatively assess the functional impact of chronic pain using measures derived from six degrees-of-freedom motion, heart rate, skin surface temperature, and skin conductivity collected via a specially designed, ergonomic wrist-worn biometric sensing instrument. The new assessment instrument will apply advanced psychometric methods to both physiologic and kinematic data to provide precise scores for functional impairment due to chronic pain. The assessment results will be presented to the clinician in an easy-to-understand report and will include longitudinal results, confidence estimates, and normative data to enable comparisons both within and between patients. The system will include provision to interface with electronic medical records. Accurate functional assessment is a crucial component in the effective treatment of chronic pain. The proposed approach will supplement existing methods for assessing patient function by providing novel and highly complementary information for a more complete (and often unobserved) picture of the impact of chronic pain on patient function. KnowPain measures will provide important data on the practical consequences of pain and on treatment efficacy.