SNY

Sanofi's experimental drug, amlitelimab, failed to meet investor expectations despite positive data from its phase III COAST 1 study. The drug is being developed as a potential successor to Dupixent, Sanofi's blockbuster eczema drug, which is set to lose patent protection in 2031. The market had high hopes for amlitelimab to meet the performance of Dupixent, but the results raised concerns about Sanofi's ability to sustain its dermatology franchise post-patent expiry.

The market perceived that Sanofi's pipeline was weak, especially in comparison to its flagship drug Dupixent. The disappointing results of amlitelimab's trial led to doubts about the company's future revenue streams, as it needs a successor to Dupixent to maintain its position in the eczema market.