“Novartis’ CDK4/6 inhibitor Kisqali has picked up Breakthrough status in the US as an initial endocrine-based treatment in certain patients with breast cancer.
“The US Food and Drug Administration has awarded the designation for of pre- or perimenopausal women with hormone-receptor positive, human epidermal growth factor receptor-2 negative (HR+/HER2-) advanced or metastatic breast cancer in combination with tamoxifen or an aromatase inhibitor.”
“At this year’s San Antonio Breast Cancer Symposium, several reports on new treatments for advanced breast cancer caught my attention. In an impressive analysis presented by Dr. Debu Tripathy, ribociclib (Kisqali, Novartis) extended progression-free survival (PFS) and improved the quality of life in young women with metastatic hormone receptor (HR) positive, HER2 negative tumors.
“Ribociclib meets ‘a clear and unmet need for premenopausal patients with HR positive, HER2 negative advanced breast cancer,’ Tripathy said at the press meeting in San Antonio. Novartis sponsored the MONALEESA-7 trial in which 672 eligible women with metastatic disease were randomized to receive hormone-blocking agents with either ribociclib or a placebo. The study registered women between age 25 and 58; the median age was around 44 years; the groups were divided evenly. The international study includes metastatic breast cancer patients in North and South America, Europe, Asia and Australia.”
“The FDA has approved co-packaging of the oral medications ribociclib (Kisqali) and letrozole (Femara) for the treatment of postmenopausal women with HR-positive, HER2-negative advanced breast cancer.
“With the new Kisqali Femara Co-Pack, patients can obtain a full 28-day cycle of the 2 medicines in 1 package with 1 prescription and 1 copay, and the cost will be the same as that for Kisqali alone, according to Novartis, which manufactures both medications.”
“The FDA recently approved ribociclib (Kisqali) for use in combination with an aromatase inhibitor as initial therapy for treatment of postmenopausal women with HR+/HER2-negative advanced or metastatic breast cancer.
“Ribociclib, an inhibitor of CDK4/6, was approved based on data from the phase III MONALEESA-2 trial, which was ended early following the first preplanned interim analysis. In this analysis, the combination of ribociclib and the aromatase inhibitor letrozole met the trial’s primary endpoint by demonstrating statistically significant improvement in progression-free survival (PFS) compared to letrozole alone.”
“The US Food and Drug Administration (FDA) has approved Kisqali®(ribociclib, formerly known as LEE011) in combination with an aromatase inhibitor as initial endocrine-based therapy for treatment of postmenopausal women with hormone receptor positive, human epidermal growth factor receptor-2 negative (HR+/HER2-) advanced or metastatic breast cancer.
“Kisqali is a CDK4/6 inhibitor approved based on a first-line Phase III trial that met its primary endpoint early, demonstrating statistically significant improvement in progression-free survival (PFS) compared to letrozole alone at the first pre-planned interim analysis. Kisqali was reviewed and approved under the FDA Breakthrough Therapy designation and Priority Review programs.”
Doctors prescribe drugs known as CDK inhibitors to treat some women with estrogen-receptor-positive (ER+) metastatic breast cancer. Research into these drugs is ongoing, and new, promising CDK inhibitor options are on the horizon. Here, I address the current outlook for CDK inhibitors in ER+ breast cancer.
First, some background: ER+ breast cancers comprise about 70% of all breast cancers. The name reflects the fact that cells of these cancers express estrogen receptors (ERs), which are protein features targeted by many treatment strategies for this cancer type. The estrogen receptor (ER) protein is a treatment target not only because “it is there,” but mainly because it drives tumor cell proliferation in ER+ breast cancer. The activity of the ER depends on its binding to the hormone estrogen, and treatments known as endocrine drugs aim to prevent this interaction. Some endocrine drugs inhibit the synthesis of estrogen in the body (e.g., aromatase inhibitors, such as letrozole and anastrozole), and others prevent the interaction of estrogen with ERs (e.g., ER modulators such as tamoxifen, or the pure anti-estrogen drug fulvestrant). The problem of course is that, in metastatic breast cancer, resistance develops to each and every endocrine drug used. Continue reading…
“The addition of a targeted agent to endocrine therapy for metastatic breast cancer led to unprecedented improvement in progression-free survival (PFS) that will have a ‘paradigm changing’ effect on clinical management, an investigator said here.
“Patients who received the cyclin-dependent kinase (CDK)4/6 inhibitor ribociclib in addition to letrozole (Femara) had a 44% reduction in the PFS hazard compared with patients treated with letrozole alone. The median PFS (primary endpoint) was 14.7 months with letrozole but had yet to be reached with letrozole plus ribociclib, ‘but it is expected to far exceed what the control arm did,’ Gabriel N. Hortobagyi, MD, reported at the European Society for Medical Oncology (ESMO) conference.”
“Continuous low-dose ribociclib shows preliminary activity, and has an acceptable safety profile as an alternative to intermittent ribociclib dosing when combined with fulvestrant in the treatment of postmenopausal women with hormone receptor (HR)-positive, HER2-negative advanced breast cancer.
“A phase Ib study, presented at the 2016 San Antonio Breast Cancer Symposium, demonstrated a confirmed partial response (PR) of 13.3% in the continuous ribociclib arm, compared with 23.1% in the intermittent ribociclib arm, but a lower rate of high-grade neutropenia in patients receiving continuous dosing of ribociclib.”
“The FDA granted a priority review to a new drug application (NDA) for ribociclib (LEE011) for use in combination with letrozole as a frontline therapy for patients with hormone-receptor (HR)–positive, HER2-negative advanced breast cancer.
“The NDA for the CDK 4/6 inhibitor is primarily based on findings from the phase III MONALEESA-2 trial, in which combining ribociclib with letrozole reduced the risk of progression or death by 44% compared with letrozole alone in the first-line setting for HR+/HER2- advanced breast cancer (HR, 0.556; 95% CI, 0.43-0.72; P = .00000329). Under the priority designation, the NDA will be reviewed within 6 months, compared with the standard 10-month review.”