In the Phase III SERENA-6 trial, camizestrant—in combination with CDK-inhibitors—beat out current standard-of-care treatments in terms of progression-free survival, according to AstraZeneca.
AstraZeneca scored a win Wednesday with its oral selective estrogen receptor degrader, reporting positive interim Phase III data for camizestrant in certain forms of breast cancer.
The SERENA-6 trial sought to determine whether switching to camizestrant in combination with CDK-inhibitors improved progression-free survival (PFS)—the study’s primary endpoint—compared to standard-of-care treatment with aromatase inhibitors (anastrozole or letrozole) with CDK-inhibitors, in patients with hormone receptor (HR)-positive, HER2-negative advanced breast cancer whose tumors also carried an estrogen receptor alpha (ESR1) mutation.
BMO Capital Markets analysts said in an investor note that camizestrant was “the first program” to demonstrate significant improvements in PFS in HR-positive breast cancer with ESR1 mutations. BMO added that the results were consistent with its expectations for the estrogen receptor degrader class given prior data from AstraZeneca’s SERENA-2 trial in patients with ESR1 mutations.
AstraZeneca did not release specific data in the announcement. The company stated it did not have mature data on secondary endpoints—time to second disease progression (PFS2) and overall survival (OS)—but said the data “demonstrated a trend toward improvement in PFS2.”
Calling the readout “critical,” Susan Galbraith, executive vice president of oncology hematology research and development at AstraZeneca, said it “moves us one step closer to realizing the potential of camizestrant to become a new standard-of-care as we look to shift the treatment paradigm and establish this new endocrine therapy backbone in HR-positive breast cancer.”
AstraZeneca intends to formally present the SERENA-6 data at an upcoming medical meeting and share the data with regulatory authorities, according to its announcement.
The camizestrant news follows several other recent positive steps in AstraZeneca’s cancer pipeline. In late November the company posted positive Phase III data for Truqap in prostate cancer data—a redemption for the AKT inhibitor, which previously failed in metastatic triple-negative breast cancer. Then in January, AstraZeneca scored the first U.S. approval for antibody-drug conjugate Datroway, developed with Daiichi Sankyo, for previously treated metastatic HR-positive, HER2-negative breast cancer.
