In early May, Novo Nordisk announced positive topline data from its Phase IIIa study STEP 4, investigating the use of semaglutide in achieving sustained weight reduction for those suffering from obesity. The STEP 4 trial is a randomised, double-blind, multicenter, placebo-controlled, withdrawal trial that explores the use of semaglutide, subcutaneously administered, in comparison to a placebo. This is significant for the global obesity market, where Novo Nordisk drug Saxenda (liraglutide) currently occupies a 55% market share. Semaglutide was designed to be administered once a week, instead of daily as required by Saxenda, which will give the new drug a leg up if approved. With that said, both drugs were developed by Novo Nordisk, so GlobalData is confident that the company will remain a leader in the obesity space, despite semaglutide undoubtedly cannibalising Saxenda sales if the former drug is approved for obesity.
The STEP 4 trial lasted for a period of 68 weeks, with semaglutide 2.4mg administered to 902 people with obesity or overweight with comorbidities. The study reports that following an initial 20-week period, the 803 people who reached the target dose of semaglutide 2.4mg had a reduced mean body weight from 107.2kg to 96.1kg. Patients were then randomised to either continue treatment with once-weekly semaglutide 2.4mg or to receive a placebo for the remaining 48 weeks; those remaining on semaglutide for the entire trial period achieved a total weight loss of 17.4%.
The primary endpoint of the trial was achieved by demonstrating that, of all randomised patients, those who continued with semaglutide 2.4mg for 48 weeks, following the initial 20-week period, achieved an additional mean weight loss of 7.9% from a mean body weight at randomisation of 96.1kg. Those who were in the placebo group regained 6.9% of their body weight, with the treatment difference proving statistically significant. In evaluating the effects of the treatment, those who remained on semaglutide 2.4mg all the way from the start of the trial achieved an additional mean weight loss of 8.8% in comparison to the placebo group, which regained 6.5%. The treatment difference is of statistical significance and patients who remained compliant to semaglutide for 68 weeks, not taking any other anti-obesity therapies, achieved a mean weight loss of 18.2%.
The STEP 4 trial demonstrates that subcutaneously administered semaglutide is highly efficacious in the treatment of obesity and has a safe and well-tolerated profile, with the most common side effect being gastrointestinal events. This side effect is common for patients taking glucagon-like peptide 1 receptor agonists, and the majority of incidents were recorded as mild to moderate in severity. STEP 4 also demonstrated semaglutide 2.4mg induces substantial and sustained weight loss in patients suffering from obesity and presents an increasing trend whereby obesity is considered a chronic disease requiring long-term treatment.
Earlier this year, Ozempic (semaglutide) received a label update towards reducing major adverse cardiovascular event (MACE) risks in patients with type 2 diabetes (T2D) and known heart disease. The drug has a strong reputation in the T2D space, as expressed by key opinion leaders interviewed by GlobalData. Its growing name recognition, combined with positive experience physicians have described from prescribing the drug, will be a key driver for rapid uptake of semaglutide, if approved for obesity. It’s also important to note that 57% of diagnosed T2D patients in the US suffer from obesity, which will likely lead physicians to increasingly favour prescribing semaglutide for treatment.