The combination can now be used to treat women with hormone receptor-positive (HR+), HER2-negative, locally advanced or metastatic breast cancer who have received prior hormone therapy.
“For many years fulvestrant has been used as an effective monotherapy treatment for women with hormone receptor positive breast cancer,” David Fredrickson, executive vice president, head of the Oncology Business Unit at AstraZeneca, said in a press release. “The first EU approval of fulvestrant for use in combination with a CDK4/6 inhibitor reinforces the value of fulvestrant as an endocrine agent of choice for advanced breast cancer patients, building on the EU first-line monotherapy approval earlier this year with FALCON.”
Faslodex is a hormonal treatment approach that helps to slow tumor growth by targeting the estrogen receptor — one of the main drivers of disease progression.
Pfizer’s Ibrance is an inhibitor of the cyclin-dependent kinases (CDK) 4 and 6, molecules that regulate cell division and proliferation. CDK4/6 inhibitors prevent cancer cells from multiplying excessively.
Faslodex is already licensed in the U.S. for use with the Ibrance since May 2016. It is also approved for use in combination with any CDK4/6 inhibitor in Japan.
The approvals stemmed from the PALOMA Phase 3 trial (NCT01942135), which examined if adding Ibrance to Faslodex was better at delaying disease progression than Faslodex alone.
The study included 521 women with HR+, HER2- advanced or metastatic breast cancer, regardless of their menopausal status, whose disease progressed after endocrine therapy.
Twenty-five percent of them had not received prior therapy for metastatic disease, and 23% had bone-only metastases.
Participants were randomized to receive Faslodex intramuscularly with or without oral Ibrance, which was given daily for 21 consecutive days followed by seven days without treatment.
The Faslodex/Ibrance treatment delayed cancer progression by 4.9 months —median progression-free survival was 9.5 months in the combination group versus 4.6 months in the group with Faslodex alone.
In the U.S., Faslodex was recently approved for postmenopausal women with HR+ HER2- advanced breast cancer who have not received prior endocrine therapy.