AstraZeneca PLC (LSE:AZN, NASDAQ:AZN) shares fell 1.9% to 13,688p after the US regulator's advisory panel declined to back its camizestrant treatment in a key breast cancer setting.
The FTSE 100 drugmaker said the Oncologic Drugs Advisory Committee of the Food and Drug Administration (FDA) voted three to six against the benefit-risk profile of camizestrant in combination with a CDK4/6 inhibitor for first-line treatment of advanced hormone receptor-positive breast cancer.
AstraZeneca noted the FDA is not bound by the panel’s recommendation but will take it into account as it reviews the application.
The decision comes despite positive data from the Phase III SERENA-6 trial, which showed a 56% reduction in the risk of disease progression or death compared with standard care.
Median progression-free survival was 16.0 months for patients on the camizestrant combination versus 9.2 months for those on existing treatments.
Susan Galbraith, executive vice president of oncology R&D, said the company was “disappointed with the mixed outcome” but remained confident in the drug’s clinical benefit.
Regulatory reviews are ongoing in other regions including the EU and Japan.
Also on Friday, AstraZeneca saw more positive news elsewhere, with a separate FDA advisory panel voting seven to one in favour of its Truqap combination for a form of prostate cancer.
The treatment showed a 19% reduction in the risk of disease progression or death in late-stage trials, supporting its potential as a targeted option in an area of high unmet need.