The story

AstraZeneca's breast cancer pill camizestrant failed to meet the primary endpoint of progression-free survival in a late-stage trial, the company said on Friday. The drug, in combination with palbociclib, was tested as a first-line treatment for patients whose breast cancer had come back or spread but had not yet received any treatment for their advanced disease. The drug combination showed a numerical improvement in delaying cancer progression compared with standard therapy, but it was not statistically significant, according to AstraZeneca.

Camizestrant works as a hormone therapy to stop estrogen from attaching to cancer cells and helping them grow. The medicine, sold with the brand name Etcamah, is approved in the European Union and received approval from the U.S. Food and Drug Administration on September 4 based on a different trial in a narrower set of patients.

AstraZeneca believes the drug could bring in over $5 billion in annual sales. Current estimates from analysts surveyed by Bloomberg put sales in 2031 at around $2 billion, and success in this group of patients could have opened up nearly $2 billion in additional sales, according to Bloomberg Intelligence.