David Kopsky
Institute for Neuropathic Pain | Netherlands
Title: From case-series to a placebo-controlled n-of-1 ‘clinical trial’ of topical analgesics in the treatment of peripheral neuropathic pain. How to enhance the level of evidence of a case-report?
Biography
Biography: David Kopsky
Abstract
Case reports have been identifi ed as relevant and important elements in advancing medical scientifi c knowledge. At our Institute for Neuropathic Pain, we treat patients suff ering from symmetrical peripheral neuropathic pain, oft en resistant to most therapies. Since 2010, we have developed a number of compounded topical formulations containing classical co-analgesics such as ketamine, baclofen and phenytoin in treatment-resistant patients and reported the results in case-reports and case-series. We were able to optimize dose and formulations based on the feedback given by the patients. Most of our patients reported a quick analgesic effect, within 20-30 minutes after applying analgesic creams. Case-reports or case series are seen as the lowest level of evidence; therefore, we adapted our approach to the n-of-1 ‘clinical trial’, seen as the ultimate strategy for individualizing medicine. This is possible for symmetrical neuropathic pain states, as a patient can compare the analgesic response on treatments (or placebo) between both feet. We developed first a single-blind placebo-controlled responder test, and currently are designing a double-blind placebocontrolled response test. These tests helped us to better identify responders and exclude placebo responders. Using a placebo in a practical setting however is not done frequently, and the ethical justifications of using such placebo will be presented, as well as the results of single-blind and double-blind response test evaluating the safety and efficacy of phenytoin cream in peripheral neuropathic pain. The above serves to underline the importance of case-reports in the emergence of new insights in medicine.