NHP Pain Models: Accelerating Analgesic Drug Development At Prisys Biotech

Pain is a major global health challenge, ranking it as the third largest health issue after cardiovascular diseases and cancer. Pain is broadly categorized into acute pain, a protective mechanism against injury, and chronic pain, which includes debilitating conditions like migraines, osteoarthritis, and diabetic neuropathy.

Current analgesics, such as opioids and nonsteroidal anti-inflammatory drugs (NSAIDs), provide relief but are fraught with significant side effects and a high risk of abuse. This creates a critical unmet need and a vast market opportunity for developing safer, more effective pain medications targeting novel mechanisms.

Voltage-gated sodium (NaV) channels, fundamental to electrical signaling in neurons, have emerged as highly promising targets for new analgesics. Of the nine NaV channel subtypes, NaV1.7, NaV1.8, and NaV1.9 are primarily expressed in peripheral sensory neurons. Notably, individuals with a loss-of-function mutation in the NaV1.7 channel are congenitally unable to feel pain, making it a prime target for drug development.

Recent breakthroughs have validated this approach. In early 2025, the FDA approved Vertex Pharmaceuticals' Journavx™ (suzetrigine), the first-in-class NaV1.8 inhibitor for moderate-to-severe acute pain. This milestone, along with major acquisitions in the NaV1.8 inhibitor space, underscores the immense potential of this target class.

However, a significant translational challenge has emerged: many small molecule inhibitors that potently block human NaV1.8 show a dramatic loss of potency against rodent channels. This species-specific difference limits the predictive value of rodent models for this class of drugs. Non-human primates (NHPs), with their high genetic similarity to humans, offer a superior and more clinically relevant platform for in-vivo screening. Prisys Biotech leverages this advantage to provide robust and predictive preclinical data.

Prisys Biotech has developed a comprehensive portfolio of innovative and validated cynomolgus monkey pain models, providing precise solutions for neuroscience drug development.

Acute Pain Models

• Capsaicin-Induced Pain Model: This model uses intradermal capsaicin injection to induce cutaneous vasodilation, a quantifiable pain biomarker measured with Laser Speckle Contrast Imaging (LSCI). The model's validity is confirmed using lidocaine as a positive control to inhibit vasodilation. Pain responses can be further assessed with tail-flick tests and BOLD functional MRI (fMRI), which detects pain-related activity in brain regions like the insula, primary motor cortex (M1), and somatosensory cortex (S1).
• Formalin-Induced Acute Pain Model: Following formalin injection, acute pain behaviors are meticulously quantified using our 3D behavioral analysis system, which detects increases in specific postures like hanging and sitting. This system captures the characteristic biphasic pain response over time.

• Partial Sciatic Nerve Ligation (PSNL) Model: This model simulates chronic neuropathic pain. Assessment includes:
• Mechanical & Thermal Hypersensitivity: A reduced pain threshold (hyperalgesia) is observed in the early post-operative phase (<10 days), which can evolve to tolerance at later stages.
• Cold Allodynia: Sustained hypersensitivity to cold stimuli (0/10/15°C) is consistently observed.
• Sensory Nerve Conduction Velocity (SCV): Post-operative measurements show significant nerve damage, evidenced by decreased velocity, prolonged latency, and reduced amplitude.
• 3D Behavioral Analysis: An increase in hanging behavior is observed in the early post-operative phase (0-11 days).

Models in Development

Prisys Biotech is continuously expanding its capabilities with new models, including:

• Spinal Nerve Ligation (SNL) for neuropathic pain.
• Chemotherapy-Induced Peripheral Neuropathy (CIPN), such as oxaliplatin-induced pain.
• These models focus on assessing spontaneous pain, mechanical/thermal hyperalgesia, and cold allodynia.

Prisys Biotech integrates cutting-edge technology to move beyond subjective scoring and provide objective, quantitative data.

AI-Powered Behavioral Analysis: Our proprietary BehaviorAtlas™ system uses high-definition cameras for 3D motion capture and skeletal reconstruction, enabling automated classification and quantification of animal behaviors. This provides precise data on events like scratching and pain-related posturing, supporting efficacy, safety, and disease characterization.

Exploratory Endpoints: We offer a range of advanced endpoints, including:

• Pain Scoring: Quantifying time spent in pain-related behaviors.
• Tail-Flick Test: A classic acute thermal pain assessment.
• Place Preference Test: Assessing pain by observing an animal's preference for different surfaces.
• Pupillometry: Measuring pupil response to noxious stimuli.
• Deep Brain EEG: Detecting pain-induced responses (~8Hz and ~80Hz for acute pain) and shifts in brainwave power associated with chronic pain.
• Precision CNS Delivery: Our real-time intraoperative MRI (RT-iMRI) navigation system ensures high-precision, safe delivery of therapeutics to the brain, which is crucial for gene therapies and other innovative treatments targeting central pain pathways.

Conclusion: Your Partner for Accelerating Analgesic Innovation

By targeting sodium channels and other novel mechanisms, the next generation of analgesics holds the promise of transforming pain management. Prisys Biotech stands at the forefront of this effort, providing a validated and efficient experimental platform for preclinical drug screening. Our comprehensive suite of NHP pain models, combined with advanced, objective assessment technologies, delivers the critical scientific evidence needed for early-stage efficacy evaluation.

Partner with Prisys Biotech to de-risk your pipeline, generate clinically relevant data, and accelerate the development of groundbreaking pain therapies.