Dupilumab

During its first-quarter conference call, Sanofi highlighted its effort to extend its patent protection for Regeneron-partnered Dupixent. The immunology blockbuster accounted for 40% of the company's sales in Q1. Normally on Big Pharma earnings calls, execs are eager to talk up their new launches and tout blockbuster expectations. But during Sanofi’s first-quarter presentation, a patent defense took center stage.The big question looming for the French company is how it will overcome the loss of exclusivity (LOE) for Dupixent when the intellectual property for the immunology superstar expires in the United States.Instead of pointing to pipeline candidates that could potentially fill the void, Sanofi highlighted (PDF) that it has a “vigorous defense planned” to extend Dupixent’s exclusivity beyond March of 2031, when the U.S. patent protecting its compound expires.In its investor presentation, Sanofi said issued patents and pending applications for new formulations could extend its protection for Dupixent all the way out to 2045. The FDA initially approved the Regeneron-partnered treatment in 2017.During a Q&A session, TD Cowen analyst Steve Scala addressed the elephant in the room, asking executives if the sudden emphasis on Dupixent’s patent protection had to do with increased confidence in its ability to extend its LOE, the timing of the LOE, the uncertainty of Sanofi’s pipeline or a change in the company’s communication strategy related to the start of the tenure of incoming CEO Belen Garijo.“There is a very strong appetite from the investor community to understand what’s coming with the LOE of Dupixent,” said Sanofi’s acting CEO, Olivier Charmeil. “This has been done—by the way—perfectly aligned with our partner as well. Regeneron had some communication about it as well at J.P. Morgan.”One way Sanofi is trying to extend Dupixent's patent protection is by developing a new formulation, dubbed Q4, that could extend its dosing interval from two to four weeks. Studies investigating Q4 are on track to begin later this year.“At the moment we’re focused on the Q4 and providing that in multiple indications,” Houman Ashrafian, Sanofi’s R&D chief, said on the call. “And then we’ll move forward on any further innovations and you wouldn’t expect us at this point to show our hand too much on those further innovations.” The emphasis on extending the LOE for Dupixent comes after a series of clinical trial setbacks and the departure of seven-year CEO Paul Hudson. High-profile candidates that flopped in 2025 included anti-OX40L-ligand antibody amlitelimab, which flunked a phase 2 asthma trial; oral TNF inhibitor balinatunfib, which came up short in a midstage psoriasis study; and Regeneron-partnered IL-33 candidate itepekimab, which failed one of a pair of phase 3 studies in COPD.Sanofi’s first-quarter results highlighted its reliance on Dupixent, which generated (PDF) sales of 4.17 billion euros ($4.9 billion), which were up 31% year over year. The figure represents 40% of Sanofi’s revenue for the quarter, which came to 10.51 billion euros ($12.3 billion), a 14% year-over-year increase. Dupixent accounted for more than all the overall revenue bump as its sales were up by 690 million euros ($808 million), compared to an overall sales increase of 614 million euros ($719 million) for the company.  One positive was the performance of rare disease drugs Ayvakit and Altuviiio, which generated combined sales of 1.75 billion euros ($2.05 billion). Meanwhile, vaccine sales were up slightly at constant currencies, landing at 1.3 billion euros during the period.