Intriguingly, a phase 2B clinical trial of tirzepatide in people with diabetes and obesity suggested that this analogue, at the highest doses tested, has superior effects on glycaemia in comparison to the benchmark GLP-1 analogue dulaglutide (reductions in HbA1c of 1.9% vs. 1.2% when given for 26 weeks) as well as weight loss (reductions of 11.3 kg vs. 2.7 kg) albeit with a worse gastrointestinal side effect profile [57]. This evidence concerns the gene GLP1R and obesity due to melanocortin 4 receptor deficiency.