Eli Lilly’s strategic moves in the weight-loss market have demonstrated a dominance that leaves its competitors in the dust.
In 2025 alone, Eli Lilly’s flagship drug tirzepatide—which had been on the market for just three years—generated over $36.5 billion in global sales, securing its place as the world’s top-selling drug.
This staggering performance propelled Eli Lilly’s market capitalization to over $1 trillion, making it the first pharmaceutical company in history to surpass the $1 trillion mark.
In contrast to Novo Nordisk’s awkward situation—where, after the overnight success of semaglutide, it lacked a successor product for an extended period—Eli Lilly has already unveiled its next-generation flagship product even before tirzepatide has reached its sales peak.
On March 19, 2026, Eli Lilly officially announced the top-line results of the first Phase 3 clinical trial (TRANSCEND-T2D-1) for its investigational triple receptor agonist, Retatrutide, in the treatment of Type 2 diabetes.
The data indicates that this is a rising star with greater efficacy and a broader scope than tirzepatide.
According to the clinical trial results disclosed by Eli Lilly, Retatrutide reduced participants’ average A1C (glycated hemoglobin) by 1.7% to 2.0%, compared to a 0.8% reduction in the placebo group.
In terms of weight metrics, participants in the 12-mg dose group lost an average of 36.6 pounds (approximately 16.8%) over 40 weeks; when calculated using a treatment regimen more reflective of real-world use, the average weight loss in the 12-mg group was 15.3%.
Eli Lilly also noted that, as of the 40-week observation point, the weight loss trend among participants continued, with no clear weight loss plateau observed.
Retatrutide is the world’s first triple-target GLP-1/GIP/GCG (glucagon) agonist to enter Phase III clinical trials. Compared to Eli Lilly’s already marketed “global blockbuster” tirzepatide (GLP-1/GIP/), Retatrutide introduces the glucagon receptor target, aiming to achieve more potent fat loss by increasing resting energy expenditure.
Results from Eli Lilly’s 2023 SURMOUNT-2 clinical trial showed that tirzepatide achieved a maximum average weight loss of 15.7% over 72 weeks in patients with “obesity/overweight and type 2 diabetes”; In contrast, Retatrutide achieved 16.8% weight loss in just 40 weeks. While direct cross-trial comparisons are not possible, this clearly demonstrates its strong competitive edge in the more challenging “obese/overweight patients with type 2 diabetes” population.
In the previously disclosed TRIUMPH-4 study targeting obese patients without diabetes, Retatrutide achieved a remarkable average weight loss of 28.7% (approximately 71.2 pounds) by week 68, and provided significant relief from knee osteoarthritis pain in 75.8% of patients.
Eli Lilly plans to continue releasing results from the TRIUMPH series of studies in 2026 and expects to submit a New Drug Application to the U.S. FDA by the end of the year.
Now, the pressure is on Novo Nordisk.
In February 2026, Novo Nordisk’s next-generation combination drug CagriSema (a combination of Cagrilin and Semaglutide) achieved a 23% weight loss in a head-to-head trial, falling short of the 25.5% achieved by the comparator drug Tirzepatide, which directly led to a sharp drop in its stock price.
Fortunately, Novo Nordisk has a drug in its pipeline that targets the same receptor as Eli Lilly’s Retatrutide.