“Eli Lilly and Company (NYSE: LLY) today announced that results from the Phase 3 MONARCH 2 study showed that abemaciclib, a cyclin-dependent kinase (CDK)4 & 6 inhibitor, in combination with fulvestrant, significantly improved progression-free survival (PFS) compared to treatment with fulvestrant alone in women with hormone-receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), advanced breast cancer who have relapsed or progressed after endocrine therapy (median PFS, 16.4 vs. 9.3 months, respectively, HR: 0.553; 95% CI: 0.449, 0.681, P < .0000001). The data were presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract #1000) and simultaneously published online in the Journal of Clinical Oncology.”
Mutations in the gene that encodes the KRAS protein are frequently encountered in various human cancers. They are found in about 30% of non-small cell lung cancers (NSCLCs), making KRAS the single most common gene mutated in this cancer. The rate of KRAS mutations in other cancers, such as pancreatic or colorectal, is even higher.
A mutant KRAS protein that is always in the “on” position activates many signaling pathways, many of which lead to unrestrained growth and proliferation of cancer cells. This makes KRAS an appealing treatment target. However, challenges abound, and researchers are exploring several different approaches to treating KRAS-mutant cancers.
Unlike mutations in proteins known as receptor tyrosine kinases, like EGFR or ALK, mutated KRAS is a very difficult protein to target with cancer drugs. (So much so that the National Institutes of Health (NIH) has undertaken a special effort to intensify the effort towards successful targeting of mutant KRAS, known as the RAS Initiative.) Continue reading…
“Adding abemaciclib to letrozole or anastrozole improved progression-free survival (PFS) compared with either aromatase inhibitor alone in women with HR+/HER2-negative breast cancer enrolled in the phase III MONARCH 3 study, according to Eli Lilly and Company, the manufacturer of the CDK4/6 inhibitor.
“MONARCH 3 (NCT02246621) is the second phase III trial of abemaciclib to demonstrate improved PFS in patients with HR+/HER2-negative breast cancer. In March, Lilly announced that in the MONARCH 2 study, combining abemaciclib with fulvestrant extended PFS compared with fulvestrant alone in patients who had progressed during or within 1 year of receiving endocrine therapy in the neoadjuvant or adjuvant setting, or during frontline endocrine treatment for metastatic disease.”
“About one in five patients with post-chemotherapy metastatic breast cancer attained an objective response to single-agent therapy with the cyclin-dependent kinase (CDK)4/6 inhibitor abemaciclib, results of a phase II trial showed.
“Responses were durable, lasting an average of almost 9 months, and more than 40% of patients obtained clinical benefit. Abemaciclib’s safety and tolerability were consistent with previous clinical experience, as no new or unexpected adverse events occurred among 132 patients who received the drug.”
“Eli Lilly and Co’s combination of its experimental breast cancer drug and another widely used treatment slowed disease progression in patients who relapsed or did not benefit enough when treated with the anti-estrogen therapy.
“In August, an independent data monitoring committee recommended the late-stage study continue without modification, even though interim evaluation suggested the combination treatment was not delaying cancer progression.
“Lilly’s drug, abemaciclib, is part of the same new class of breast cancer treatments as Pfizer Inc’s Ibrance, and Novartis AG’s newly approved Kisqali.”
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…
“A neoadjuvant regimen combining the CDK4/6 inhibitor abemaciclib with anastrozole induced a response rate of 54.7% in patients with HR+/HER2-negative early-stage breast cancer, according to findings from the phase II neoMONARCH trial presented at the 2016 San Antonio Breast Cancer Symposium.
“The study also met its primary endpoint of reduction in Ki67 expression level at week 2. The abemaciclib combination yielded a geometric mean change in Ki67 from baseline to day 15 of -92.6%.”
“Neoadjuvant abemaciclib with or without anastrozole led to significantly greater reductions in tissue Ki67 after 2 weeks of treatment than anastrozole alone among postmenopausal women with hormone receptor–positive, HER-2–negative breast cancer, according to interim phase 2 study results presented at the European Society for Medical Oncology Congress.”
“U.S. drugmaker Eli Lilly and Co on Wednesday said it would continue a late-stage trial of its experimental breast cancer drug in combination with a widely used treatment even though an independent panel determined the combination therapy failed to meet its interim effectiveness goal.
“The independent data monitoring committee recommended the trial continue without modification through the first half of 2017 despite the fact that its interim look at the data suggested the combination treatment was not delaying progression of the disease.”
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