The European Commission’s (EC) authorization of Eli Lilly’s Mounjaro (tirzepatide) for treating type 2 diabetes (T2D) is of paramount interest to patients as the drug has the potential to address a key unmet need by introducing a new mechanism of action into the T2D space—which is expected to reach $91.6 billion by 2029 as forecasted by leading data and analytics company GlobalData in 2021—and potentially the obesity space.

Mounjaro is a glucagon like peptide 1 (GLP-1) receptor agonist, similar to many other treatments for T2D and obesity on the market, including Novo Nordisk’s Wegovy (semaglutide) and Saxenda (liraglutide). However, Mounjaro stands out by offering a unique feature unlike other GLP-1 receptor agonists; it is also a gastric inhibitory polypeptide (GIP) receptor agonist, thereby working in a dual receptor agonist fashion. This has many implications for patients; in SURPASS-2 (NCT03987919), a head-to-head comparison study of tirzepatide against semaglutide as a once weekly add-on therapy to metformin, tirzepatide outperformed the latter across all dose groups in patients with T2D.

Sara Reci, Pharma Analyst at GlobalData, comments: “Hope for Mounjaro’s approval for obesity proceeding follows suit of Novo Nordisk’s course of action with semaglutide, which was originally approved in 2017 for its use in patients with T2D, marketed under the name Ozempic, and later followed by its approval for obesity in 2021, marketed under the name Wegovy and available at higher doses.”

In the Phase III trial SURMOUNT-1 (NCT04184622), which was conducted in patients with overweight and obesity, Mounjaro demonstrated a mean weight reduction of 13kg in pooled data from the 10mg and 15mg treatment arms by week 72 of the study, whereas a mean weight reduction of 24kg was reached in the 15mg treatment study group alone. With respect to its safety profile, adverse events ranged from mild to moderate among subjects, and treatment discontinuation due to adverse events was 6.2% in the 15mg dose group. Overall, Mounjaro’s safety and efficacy results were promising.

Reci concludes: “There is no doubt that Mounjaro has overwhelming potential to be favored among many patients and clinicians alike should it be approved for obesity. Following the promising results of Phase III studies, this new therapy may be on a trajectory to compete directly with GLP-1 agonists across the obesity space.”