Table 3.
Potential pain biomarkers used in clinical trials
| Pain disease state | Biomarker | Correlation to disease | Correlation with pharmacodynamic outcome | Correlation with pain state | Clinical efficacy shown |
|---|---|---|---|---|---|
| Rheumatoid arthritis and neuropathic pain | CCL concentration in cerebrospinal fluid and plasma | CCL in neuropathic pain | Highly efficient antagonism of CCR2 | No | No236,237 |
| Inflammatory pain | TRPV expression | TRPV elevated | TRPV antagonism leads to reduction in inflammation | Yes | No238,239 |
| Chronic back pain | Nerve growth factor | High | High | Yes | Yes240 |
| Migraine | CGRP concentration | Elevated in disease state | Yes | Yes | Yes241 |
| Neuropathic pain | Resting-state functional connectivity, temporal summation of pain | No specific correlation | Unknown | Yes | Yes148 |
| Painful diabetic neuropathy | Conditioned pain modulation | No specific correlation | Yes | Yes | Yes242 |
| Migraine, fibromyalgia (nociplastic pain) | Conditioned pain modulation | Poor conditioned pain modulation capacity | Yes | Yes | Yes183,243–245 |
CCL, CC-chemokine ligand; CCR2, CC-chemokine receptor 2; CGRP, calcitonin gene-related peptide; TRPV, transient receptor potential cation channel subfamily V.