Repurposing and re-positioning of old treatments for new indications: A focus on addictive disorders

Abstract

Introduction and Aims There are a plethora of biomedical treatments used in mainstream medical practice, for many well‐known diagnoses, some dating back for centuries. Despite the aging of most populations worldwide and the increasing global burdens of various diseases in recent decades, there has been a relative paucity in development of new treatments for neuropsychiatric conditions in particular. This is potentially due to big pharma retreating, microeconomic and macroeconomic constraints and the fastidious process of developing and then testing new molecules or treatments on a complex human brain. The benefits of psychological, behavioural, mutual help and other treatments are generally well known and accepted; however, limitations for their use exist also. The author aims to summarise how some older medications are being used for new indications, in particular relating to addictive disorders.

Design and Methods A précis of relevant literature and anecdotes is presented. The author presents an opinion on current trends in ‘off label’ medication use, and offer a glimpse into potential future applications.

Results Numerous novel ways of repurposing treatments were discovered, including oxytocin for alcohol use disorder, lisdexamfetamine for stimulant use disorder and N‐acetyl cysteine for cannabis use disorder. A case series on subcutaneous flumazenil infusions for benzodiazepine use disorder was outlined.

Discussion and Conclusions The modern era of medicine comes with it hope but also a degree of constriction which conflates to drive flexible and creative ways of treating refractory conditions. Amongst addictive disorders alone, there are a number of potentially beneficial repositioned treatments for which little or no research/consensus exists. The reasons driving a request (or behest), acceptance or reluctance to trial old approaches for novel reasons is often not congruent with evidence or based on biological plausibility. The scope for further research with many of these treatments is limited due to lack of financial incentives, but potentially less onerous if safety has been established in previous Phase I and II trials for other conditions.

Disclosure of Interest Statement The author declares no conflict of interests related to this manuscript. TM has received honoraria, fees and/or provision of professional development resources from Servier, Otsuka/Lundbeck, Australian and New Zealand Mental Health Association, and Healthe Care. He works in the private sector and receives income for clinical services provided.