Bayer Halts Development of Eliapixant Due to Safety Concerns

Bayer has decided to stop the development of eliapixant, an investigational P2X3 receptor antagonist, after concluding that the risks outweigh the benefits for its intended uses, including refractory chronic cough, endometriosis, overactive bladder, and diabetic neuropathic pain. This decision comes shortly after the FDA rejected Merck & Co's gefapixant, another P2X3 antagonist, due to safety concerns.

Eliapixant, previously known as BAY1817080, showed promising results in reducing the 24-hour cough count in patients with chronic cough and was well-tolerated in clinical trials. However, Bayer's review of the data led to the conclusion that the drug's overall benefit no longer justifies the risk.

Bayer had licensed eliapixant from Evotec and has now returned the rights to the P2X3 program to the German biotech firm, although both companies continue to collaborate on other research and development projects. Evotec plans to evaluate the data and consider all options moving forward.

The discontinuation of eliapixant's development has impacted the stock prices of both Evotec and Bayer, with Evotec's shares falling by approximately 10%. This news also affected Bellus Health, whose P2X3 drug BLU-5937 is next in line in clinical development after gefapixant. BLU-5937 recently showed positive results in a mid-stage trial for refractory chronic cough and is expected to enter phase 3 trials later this year.

Despite the setback for Bayer, Merck remains committed to gefapixant, which has been approved in Japan under the name Lyfnua for chronic cough. Merck is working with the FDA to address the concerns and find a path forward for the drug in the US, where there are currently no approved therapies for refractory chronic cough, a condition affecting an estimated 5% to 10% of the global population.