The pharmaceutical industry has seen tremendous growth in revenue over the years, with companies like Merck & Co. leading the way with their cancer blockbuster Keytruda. However, as new products enter the market and patents expire, legacy drugs inevitably see a decline in sales. This shift in the market landscape affects the fortunes of the companies that produce these drugs.
One such example is Eli Lilly’s diabetes drug Trulicity, which was once a top-selling product for the company. However, with the approval of the GLP-1 Mounjaro, Trulicity started to see a decline in sales. In the first half of 2025, Trulicity’s sales dropped by 19%, losing over $500 million in revenue. This decline was primarily driven by the introduction of Mounjaro, which showed comparable cardiovascular outcomes to Trulicity.
Johnson & Johnson also faced challenges with their immunology blockbuster, Stelara, as it lost exclusivity and faced competition from biosimilars. Sales of Stelara fell by over 38% in the first half of 2025, but J&J’s overall immunology portfolio saw a 4% increase thanks to other successful products like Remicade and Tremfya.
AbbVie’s once top-selling drug, Humira, also experienced a significant decline in sales, dropping by 55% in the first half of 2025. However, newer immunology drugs like Skyrizi and Rinvoq helped AbbVie offset the loss and bring in over $11 billion in revenue.
Roche’s breast cancer drug, Herceptin, saw a 21% decline in sales in the first half of 2025, but the company managed to introduce a new combination product, Phesgo, which helped boost sales by 55%. Additionally, Roche’s partnership with Sarepta Therapeutics led to a 316% increase in sales of the Duchenne muscular dystrophy therapy Elevidys.
AstraZeneca faced challenges with their RSV monoclonal antibody, Synagis, which saw a significant drop in sales to $162 million in the first half of 2025. Despite this, the company’s portfolio of products like Ultomiris and Symbicort helped offset the decline in sales of other products like Soliris and Pulmicort.
Overall, the pharmaceutical industry is constantly evolving, with new products entering the market and legacy drugs facing challenges. Companies must adapt to these changes to stay competitive and continue to innovate in the ever-changing landscape of healthcare.
