Sanofi,Regeneron Stocks Plunge 6.17%,13.77% on Mixed COPD Drug Trial Results

On Friday, before the U.S. stock market opened, shares of Sanofi (SNY.US) and Regeneron (REGN.US) experienced notable declines. Sanofi's stock price fell by 6.17%, while Regeneron's stock price dropped by 13.77%. The decline was attributed to the mixed results of a clinical trial for an experimental drug aimed at treating a fatal lung disease.

The experimental drug, Itepekimab, was jointly developed by Sanofi and Regeneron to treat chronic obstructive pulmonary disease (COPD) in former smokers. The trial results were contradictory: one late-stage trial showed a 27% reduction in disease progression, while another did not demonstrate the same efficacy, despite early indications of success.

Sanofi and Regeneron are currently evaluating the data and will discuss the findings with regulatory authorities. Houman Ashrafian, the head of Sanofi's research and development department, stated that the results of the two studies warrant further exploration to fully understand how the drug interacts with a protein called IL33, which contributes to the inflammation associated with this complex disease. IL33 levels are elevated in the lungs of former smokers.

Analysts are closely monitoring the trial data for Itepekimab, as Sanofi's blockbuster drug Dupixent is nearing the end of its patent protection. Dupixent is approved for treating multiple conditions, including COPD, and has been a significant driver of Sanofi's growth. Other pharmaceutical companies, such as GlaxoSmithKline, are also developing treatments for COPD. GlaxoSmithKline's Nucala was recently approved in the U.S. for treating COPD.

The mixed results of the Itepekimab trial present a significant setback, potentially delaying the drug development process by at least three years. Analysts note that while many COPD drugs initially failed to show benefits for some patients in detailed analyses, there is still hope for this potential drug. Other applications are still under investigation.