Deliberately inflicting carefully controlled painful stimuli on human volunteers and seeing how well specific drugs reduce the feeling of pain can be an effective way of testing new drugs, according to a new literature review study published in the British Journal of Pharmacology.
“We thought that if a pain-relieving drug was effective in a particular experimental pain model and also in a specific type of clinical pain, then the experimental model should be predictive for the particular clinical setting,” said Jörn Lötsch, study author from the Institute of Clinical Pharmacology at the Goethe-University, Germany.
The researchers found that overall, human experimental pain models were able to predict how well a drug worked in patients better than previously realised. “Not using these pain models in drug development seems to be unjustified in fact they should be used routinely in drug development programmes,” said Bruno Georg Oertel, study author from the Fraunhofer Project Group for Translational Medicine and Pharmacology (TMP), an initiative supported by the Hessian Excellence Initiative (LOEWE) that runs at the junction between pharmacological research in academia and in the pharmaceutical industry.
The process is not simple though as not every model can predict every clinical setting. “However, by analysing the way that drugs work in experimental and clinical settings, we identified that different sets of experimental pain models, rather than single models, may be best suited to provide cost-effective yet predictive studies in analgesic drug development,” said Lötsch.
“It is difficult and unusual to undertake truly translational research in pharmacology. Here, Jörn Lötsch and Bruno G. Oertel have focused on experiments on humans to bridge the gap between animal research and clinical pharmacology. The review examines how well clinical analgesia is predicted by human experimental pain models, with a view to guiding model selection in phase I studies. The authors identify important disparities between drug effects on experimental and clinical pain. This will help inform thinking on the refinement of human and animal models of pain, ultimately helping the pharmaceutical industry bridge the translational gap in the pain field,” said Ian McGrath, editor-in-chief of the British Journal of Pharmacology.
More work is needed before this approach is fully ready to use, but the researchers believe this could lead to a more cost effective approach that can help scientists gain valuable information about the ways new drugs are working.