The Reign of Immunotherapy: Keytruda's Dominance
For years, the anti-inflammatory drug Humira (adalimumab) held the top spot as the world's highest-selling drug. However, this reign ended dramatically due to increased biosimilar competition following its patent expiry in 2023. Humira's annual sales plummeted by nearly 38% in 2024, falling to around $9 billion, paving the way for a new pharmaceutical leader.
The highest-selling drug in the market in 2024 was Merck's immuno-oncology blockbuster, Keytruda (pembrolizumab). With a commanding 18% increase in sales, Keytruda's revenue soared to an estimated $29.5 billion, driven by its extensive range of approved cancer indications, which now number over 40. Keytruda is a PD-1 inhibitor that works by blocking the PD-1 protein on immune cells, essentially taking the 'brakes' off the immune system so it can recognize and attack cancer cells. This broad utility and high efficacy across numerous cancer types, including lung and gynecological cancers, have cemented its status as a cornerstone of modern cancer therapy.
The Rise of Metabolic Blockbusters
While Keytruda dominated the top spot, the pharmaceutical landscape is being rapidly reshaped by a new class of drugs: glucagon-like peptide-1 (GLP-1) receptor agonists. Medications like Novo Nordisk's Ozempic (semaglutide) and Eli Lilly's Mounjaro (tirzepatide) have seen explosive growth not only for their original use in managing type 2 diabetes but also for their potent weight-loss effects.
- Ozempic and Wegovy (semaglutide): Novo Nordisk’s semaglutide products collectively generated significant revenue in 2024, with Ozempic specifically bringing in over $17 billion. The sales were boosted by its effectiveness in reducing cardiovascular risk and a surge in demand for its weight-loss formulation, Wegovy.
- Mounjaro and Zepbound (tirzepatide): Eli Lilly's tirzepatide products also achieved blockbuster status, with Mounjaro hitting $11.54 billion in sales in 2024, a 123.5% increase year-over-year. These GLP-1 drugs are creating a major new therapeutic area and revenue stream, posing a serious future challenge to oncology's dominance.
Market Forces and the Battle for Supremacy
The pharmaceutical market is a dynamic environment where the fate of blockbuster drugs is determined by a complex interplay of innovation, market access, and competitive pressures. The fall of Humira provides a powerful example of how patent expirations can completely redefine the market, with biosimilar versions chipping away at its once-unassailable market share. The impending patent expiration for Keytruda around 2028 is a critical factor that could once again shift the market hierarchy.
Government regulations, such as the Inflation Reduction Act (IRA) in the U.S., are also exerting significant pressure on drug pricing and profits. While designed to lower costs, these measures can dampen future revenue potential for high-cost therapies like Ozempic and Eliquis, which have been selected for price negotiations. Companies are responding by expanding indications, developing new delivery methods (like a subcutaneous version of Keytruda), and investing heavily in pipeline drugs to offset potential revenue losses.
A Comparison of Top-Selling Drugs (2024)
| Rank | Drug Name (Brand) | Manufacturer(s) | Primary Indication | 2024 Sales (approx.) | Key Market Trend |
|---|---|---|---|---|---|
| 1 | Keytruda (pembrolizumab) | Merck & Co. | Oncology | ~$29.5 billion | Market leader with broad cancer indications; facing future patent expiry |
| 2 | Eliquis (apixaban) | Bristol Myers Squibb & Pfizer | Cardiovascular/Hematology | ~$20.7 billion | Strong demand, but facing patent expiration and price negotiation pressures |
| 3 | Ozempic (semaglutide) | Novo Nordisk | Metabolic Diseases | ~$17.5 billion | Explosive growth driven by diabetes and weight-loss demand |
| 4 | Dupixent (dupilumab) | Sanofi & Regeneron | Immunology/Respiratory | ~$14.1 billion | Robust growth fueled by expanding immunology indications |
| 5 | Biktarvy (bictegravir) | Gilead Sciences | HIV | ~$13.4 billion | Cornerstone of HIV therapy; patent protection until 2033 |
| 6 | Mounjaro (tirzepatide) | Eli Lilly | Metabolic Diseases | ~$11.5 billion | Rapidly gaining market share in diabetes and obesity |
| 7 | Skyrizi (risankizumab-rzaa) | AbbVie | Immunology | ~$11.7 billion | Strong growth offsetting declines in former blockbuster Humira |
Conclusion: The Evolving Pharmaceutical Market
The question of what is the highest selling drug in the market is not static; it is a snapshot of an ever-evolving field driven by scientific innovation and market dynamics. In 2024, Keytruda's dominance underscored the immense commercial value of novel cancer treatments, while the meteoric rise of GLP-1 agonists highlighted a transformative shift toward metabolic disorders. The industry faces significant headwinds, including patent expirations and increasing regulatory scrutiny over pricing, which will likely continue to reshape the leaderboard in the years to come.
As pharmaceutical companies race to innovate and protect their intellectual property, the landscape of top-selling drugs will remain a powerful indicator of both medical progress and commercial strategy. For a deeper look into the business side of this dynamic sector, consider reading further industry analysis from leading business publications.
Authoritative Link from BioSpace discussing 2024's top sellers and future challenges.
