Vishvarani Wanigasekera

Clinical Research Fellow, Nuffield Department of Clinical Neurosciences, University of Oxford, United Kingdom.

Placebo effects in RCTs: Emerging neuroimaging evidence and implications for the additivity model in RCTs.

Chronic pain is poorly managed, lack of effective analgesics being one of the key reasons. Inherent variability in subjective pain reports and the expectation driven effects on pain reports make assessment of analgesics efficacy challenging especially during early analgesic drug development. The current gold standard of demonstrating analgesic efficacy is by using RCTs that include a placebo arm. Here analgesic efficacy is assumed if the drug arm shows pain relief beyond that seen in the placebo arm. The validity of this additivity model is being currently questioned. I will present emerging evidence from neuroimaging studies that support this view



Dr. Wanigasekera is a Clinical Research fellow in the Anaesthesia, Pain and Analgesia Neuroimaging Group lead by Prof. Irene Tracey at the University of Oxford. She is also a practicing clinician at the Oxford University Hospitals Trust with clinical commitments as an intensivist in the Cardio Thoracic Critical Care Unit at the John Radcliffe Hospital.

Her research interests focus on understanding pain and analgesia mechanisms to optimize pain relief in chronic pain. These include validating neuroimaging as a biomarker for early analgesic drug development and characterising the placebo effects in a clinical trial setting. Dr. Wanigasekera received her D.Phil from University of Oxford for her work on the investigation of human brain mechanisms of opioid pharmacodynamics using neuroimaging. In this body of work, she explored the role of reward circuitry in predicting opioid analgesic efficacy and the interaction between expectation and opioid analgesic efficacy.