In a head-to-head trial, Zepbound from Eli Lilly resulted in more significant weight loss compared to Wegovy from Novo Nordisk.

• In the first head-to-head clinical trial comparing Eli Lilly's Zepbound and Novo Nordisk's Wegovy, Zepbound led to more weight loss than Wegovy.
• On average, patients with obesity or who are overweight lose 20.2% of their body weight after 72 weeks when using Zepbound for weight loss.
• On average, individuals who used Wegovy lost 13.7% of their weight over the same time frame.

In the first head-to-head clinical trial comparing weekly injections of Zepbound and Wegovy, Zepbound led to more weight loss than Wegovy.

On average, patients who took Zepbound lost 50 pounds, while those who took Wegovy lost 33 pounds after 72 weeks in the phase three trial.

Zepbound outperformed Wegovy in a trial, achieving a 47% higher relative weight reduction and having more than 31% of participants lose at least a quarter of their body weight, compared to 16% of those on Wegovy who achieved the same level of weight loss.

Recent research suggests that Zepbound is more effective in weight loss than Wegovy. Specifically, a study on Zepbound found that it helped patients lose an average of more than 22% of their weight over 72 weeks, while a separate study on Wegovy showed that it led to an average weight loss of 15% over 68 weeks.

The Wednesday data is the most concrete evidence of Zepbound's edge, as the trial randomly assigned 751 patients to receive the maximum dose of either drug. The study specifically followed patients who were obese or overweight with at least one weight-related medical condition, not including diabetes.

To aid health care providers and patients in making informed decisions regarding treatment options for obesity, a study was conducted due to the growing interest in obesity medications, as stated by Dr. Leonard Glass, senior vice president of global medical affairs at Eli Lilly Cardiometabolic Health, in a release.

Eli Lilly is yet to release the results, which it intends to publish in a peer-reviewed journal and present at a medical conference next year.

Both drugs commonly cause mild to moderate gastrointestinal side effects.

Eli Lilly's larger market share in the booming weight loss drug market is a huge advantage due to Zepbound's greater weight loss, which is expected to be worth $150 billion a year by the early 2030s.

Although Wegovy entered the market two years before Zepbound, which was approved in the U.S. in late 2023, some analysts believe that Zepbound has a strong chance of becoming the best-selling drug of all time after more years on the market.

According to data from November, GlobalData predicts that Zepbound will generate $27.2 billion in annual sales and Wegovy will achieve $18.7 billion in annual revenue by 2030.

The high demand for Zepbound, Wegovy, and their diabetes equivalents has exceeded their supply over the past year, prompting Eli Lilly and Novo Nordisk to invest billions in increasing their manufacturing capacity for these injections. According to the Food and Drug Administration, all doses of these treatments are now listed as "available" on their drug shortage database.

Despite the inconsistent insurance coverage for weight loss treatments in the U.S., both Zepbound and Wegovy cost approximately $1,000 per month without insurance or savings.

The treatments work differently.

Activating GLP-1 and GIP hormones helps regulate appetite and blood sugar levels, and Wegovy specifically targets GLP-1, while some researchers suggest that targeting GIP may also affect sugar and fat breakdown.