Top 10 Best-Selling Drugs Globally in 2025 Forecast: K Drug Leads, GLP-1 Drugs Rise

The journal Nature Reviews Drug Discovery recently published a predictive analysis of the top 10 best-selling drugs globally in 2025. Pembrolizumab, commonly known as "K Drug," is expected to become the leading drug for the year, followed closely by semaglutide and its competitor tirzepatide, excelling in the weight loss sector. This prediction aligns with the sales performance of these drugs in the first three quarters of the year.

Among the top ten best-selling drugs forecasted, four belong to the GLP-1 class, all of which fall under metabolic therapy. Additionally, two autoimmune drugs, Dupixent (dupilumab) and Skyrizi (risankizumab), remain regulars on the best-seller list, ranking fourth and fifth, respectively.

In the 2025 forecast, "K Drug" continues to hold its top position. In 2023, pembrolizumab's global sales reached $25.011 billion, marking its first year as the world's best-selling drug and earning it the title of "king of drugs." In the first half of 2024, "K Drug" maintained this status with sales of $14.217 billion. According to Merck's financial report, in the first three quarters of 2024, pembrolizumab contributed $21.646 billion, an 18% increase year-on-year.

The strong growth in pembrolizumab's sales is attributed to the continuous expansion of its indications. Since its launch in 2014, the drug has received approval for 40 indications worldwide, covering various cancer types. Since 2023, it has added ten new indications, including cervical cancer.

GLP-1 class drugs, as one of the three popular targets for non-insulin antidiabetic drug development, show significant potential and broad market prospects in the weight loss drug sector. In this forecast list, four GLP-1 products made the cut, with two being semaglutide from Novo Nordisk and the other two being tirzepatide from Eli Lilly.

In December 2017, the FDA approved semaglutide for treating type 2 diabetes under the brand name Ozempic. In June 2021, a higher dosage of semaglutide was approved for weight loss under the brand name Wegovy. Novo Nordisk's financial report indicates that in 2023, Ozempic's sales reached 65.653 billion Danish kroner (approximately 69 billion RMB), a 53% year-on-year increase, while Wegovy's sales reached 21.729 billion Danish kroner (approximately 22.839 billion RMB), a staggering 481% year-on-year increase.

Its competitor Eli Lilly is also making strides. In November 2023, Eli Lilly's weight loss drug tirzepatide (brand name: Zepbound) received FDA approval for obesity or overweight indications. Unlike semaglutide, tirzepatide is a dual-target agonist for GLP-1R/GIPR. In May 2022, the FDA approved it for improving blood sugar control in adults with type 2 diabetes under the brand name Mounjaro. Eli Lilly announced in October 2023 that results from the SURMOUNT-3 phase III clinical trial showed tirzepatide's weight loss effect was superior to semaglutide, drawing widespread attention.

Since its launch in 2023, Zepbound has achieved $483 million (approximately 3.429 billion RMB) in sales in less than nine months. In the first three quarters of 2023, the drug's sales reached $2.96 billion (approximately 21.016 billion RMB), a year-on-year increase of 1354%.