The European Commission (EC) has approved fulvestrant for the treatment of oestrogen-receptor positive, locally-advanced or metastatic breast cancer in postmenopausal women not previously treated with endocrine therapy.

The EU approval is based on pivotal data from the Phase III FALCON trial, which demonstrated the superiority of fulvestrant 500mg over anastrozole 1mg as a first-line treatment for postmenopausal women with locally-advanced or HR metastatic breast cancer who had not received prior hormone-based therapy.

In the FALCON trial, median progression-free survival (PFS) was significantly longer with fulvestrant than with the aromatase inhibitor, anastrozole - 16.6 months versus 13.8 months (HR: 0.797; 95% CI: 0.637-0.999; p=0.0486). 

Fulvestrant is the only hormonal medicine for advanced breast cancer that slows tumour growth by binding to and degrading the oestrogen receptor - a key driver of breast cancer progression in some women. 

It is widely approved for the treatment of HR advanced breast cancer in postmenopausal women with disease progression following anti-oestrogen medicine.

Aromatase inhibitors such as anastrozole are the current standard of care for the first-line treatment for postmenopausal women with HR advanced breast cancer.

Dr Matthew Ellis, study investigator, and director of the Lester and Sue Smith Breast Center in the Dan L Duncan Comprehensive Cancer Center at Baylor College of Medicine in Houston, said “A 20% reduction in disease progression or death observed with fulvestrant compared to the current standard therapy is an advance in the management of postmenopausal women diagnosed with previously untreated hormone receptor-positive advanced breast cancer. The study provides evidence that the earlier use of fulvestrant in these patients will prolong the time before the disease progresses, which requires a change to a second line drug.”

The safety and tolerability profiles for fulvestrant and anastrozole reported in the FALCON trial were in line with current experience.

The most-commonly reported adverse events (AEs) in the fulvestrant and anastrozole arms were arthralgia (16.7% vs. 10.3%), hot flush (11.4% vs. 10.3%) and nausea (10.5% vs. 10.3%).

Source: AstraZeneca