The area of genetic causes of syndromic and non-syndromic obesity has a large unmet clinical need to treat underlying hyperphagia. In recent years, improved understanding of underlying mechanisms resulting from the underlying gene(s) defects has revealed potential therapeutic targets, while designation of orphan disease has promoted the interest of biotechnology and pharmaceutical companies for these rare genetic obesities. This talk will review the emerging trial data on the use of Setmelanotide, a melanocortin-4 receptor (MC4R) agonist, to treat genetic obesity due to variants affecting the leptin-pro-opiomelanocortin (POMC)-MC4R pathway, particularly for POMC deficiency, leptin receptor (LEPR) mutations, PCSK1 deficiency, Bardet-Biedel syndrome, and chromosome 16p11.2 deletions involving SH2B1 gene or SH2B1 variants. Meanwhile for Prader-Willi syndrome (PWS), the commonest cause of syndromic obesity, there has been more limited success from clinical trials. No benefit has been evident using Setmelanotide, Livoletide (desacyl ghrelin analogue), nor GLWL-01 a ghrelin-O-acyltransferase (GOAT) inhibitor, but some efficacy in reducing hyperphagia has been seen with Carbetocin/oxytocin and DCCR controlled-release diazoxide. Several ongoing and upcoming trials in PWS are assessing potential for the GLP-1 analogue Liraglutide, and drugs targeting histamine/monoamine systems and potential downstream targets that are more proximal to the underlying PWS genes such as PCSK1. Meanwhile, the benefits of specialist residential homes for adults with PWS remains life-saving by providing an environment with rigorous control of the access to food with promotion of physical activity. However, their limited geographical availability, delays navigating funding pathways between NHS Continuing Healthcare and social care, and issues around capacity and patient/family reluctance to consider such residential options can produce barriers to their utilisation.
30 Jun 2021 - 01 Jul 2021