Patients taking Lilly’s retatrutide shed more than twice the body weight of those on Ozempic, a result that Citi says meaningfully intensifies competitive pressure on Novo Nordisk (NYSE: NVO).
The figures emerged from Lilly’s phase III TRANSCEND-T2D-2 trial, where retatrutide achieved weight reductions of 19.5% at the 9mg dose and 20.9% at the 12mg dose over 80 weeks.
Ozempic, by contrast, produced weight loss of just 9.4% at its highest approved dose of 2mg, less than half the reduction recorded with either retatrutide regimen.
Retatrutide’s advantage extended beyond weight loss, with blood sugar control also superior: HbA1c declined 2.2% among retatrutide patients versus 1.8% for those on Ozempic.
The drug works by targeting three separate receptors simultaneously, combining action on GIP, GLP-1, and glucagon pathways, unlike the more narrowly targeted mechanism behind Ozempic.
Critically for commercial prospects, those efficacy gains did not appear to come with a dramatically worse side effect burden, a finding that Citi flagged as particularly significant for the competitive outlook.
Nausea rates were broadly comparable, running between 21% and 24% for retatrutide against 21% for Ozempic, and constipation was actually lower at 13% to 14% versus 20%.
Some gastrointestinal measures were less favorable for retatrutide, with diarrhoea recorded in 28% to 33% of patients compared with 26% on Ozempic, and vomiting ranging from 10% to 15% against 13%.
Discontinuation due to adverse events was higher on retatrutide, affecting 4.8% to 7.9% of patients versus 2.7% on Ozempic, though Citi described the overall tolerability profile as broadly manageable and in line with earlier retatrutide studies.
Dysaesthesia, a sensory disturbance, was reported in 5% to 7% of retatrutide patients compared with 3% among those taking Ozempic, adding a further differentiator to the two drugs’ safety profiles.
Citi kept its ‘neutral/high risk’ rating and a target price of Dkr296.00 on Novo Nordisk, concluding that the combined efficacy and tolerability results were incrementally negative for the Danish drugmaker.
The bank said the trial outcome further raises the competitive bar in both obesity and type 2 diabetes, two markets where Novo Nordisk has built much of its recent commercial momentum.
