Advancing Outcome Measure Development and Analytical Approaches: Pain in Animals Workshop (PAW) 2023

B. Duncan X. Lascelles^1*Daniel Barratt²Parminder Basran³Dottie Brown⁴Johann (Hans) Coetzee⁵Marie Gill⁶Mark R Hutchinson²Cheryl Johnson⁷Stelio Pacca Loureiro Luna⁸Mohapatra Dp⁶Michael L. Oshinsky⁶Sheilah Robertson⁹Claire Ruberman⁷Emily Smith⁷Qiao Zhang⁷

• ¹North Carolina State University, Raleigh, United States
• ²University of Adelaide, Adelaide, South Australia, Australia
• ³College of Veterinary Medicine, Cornell University, Ithaca, New York, United States
• ⁴Mars Veterinary Health, Vancouver, Kentucky, United States
• ⁵Kansas State University, Manhattan, Kansas, United States
• ⁶National Institute of Neurological Disorders and Stroke (NIH), Bethesda, Maryland, United States
• ⁷Center for Veterinary Medicine, United States Food and Drug Administration, Laurel, Maryland, United States
• ⁸University of São Paulo, São Paulo, Rio Grande do Sul, Brazil
• ⁹Lap of Love, Lutz, United States

Annually, millions of humans and animals suffer from chronic and acute pain, creating welfare and quality of life concerns for both humans and animals who suffer this pain. In developing new therapeutic approaches, the challenge is to accurately measure this pain to ascertain the efficacy of novel therapeutics. Additionally, there is a need to develop new and effective analgesic options that may offer alternatives to using opioids that contribute to the opioid epidemic. The Pain in Animals Workshop (PAW) meetings are held every other year in partnership with the National Institutes of Health (NIH), bringing key stakeholders together to understand pain in humans and animals better. The 2023 workshop focused on presenting and discussing updates on validated approaches to measuring pain, highlighting opportunity areas for additional outcome measure development. It also discussed study design and analytic approaches to the use of outcome measures in clinical trials, including the important concepts of success-failure approaches and the application of multiple endpoints in evaluating analgesic therapies. The workshop also introduced the concept of the biopsychosocial model of pain, broadening the conversation around the impact of pain and thus opportunities to modulate the pain experience. The application of artificial intelligence to the measurement of pain was introduced. The workshop brought together academia, government, and industry experts in human and animal pain assessment and analgesic intervention development. Given the topic’s importance and the meeting’s uniqueness, capturing the thoughts and ideas presented and discussed is critical. This narrative is one product from that meeting, summarizing several presentations from the workshop.