The Food and Drug Administration Tuesday
approved abemaciclib as a maintenance drug for breast cancers that are estrogen receptor positive, which account for two-thirds of all breast cancers, Lustberg said. It can be given along with estrogen blockers that typically are given after surgery, chemotherapy or radiation, she said. It is marketed by Eli Lilly & Co. as Verzenio .
The drug differs from chemotherapy in that it targets a particular mechanism in the cancer cell, rather than all rapidly multiplying cells. “We call them smart pills or targeted therapies because they target a very specific part of tumor growth,” Lustberg said. Abemaciclib targets two enzymes that are “related to the growth machinery of the tumor cells ... They essentially put the brakes on it,” she said.
“This FDA approval is essentially adding a second pill to help the estrogen pill work better,” Lustberg said.
“You had patients who maybe had a higher risk of breast cancer, higher stage, positive lymph nodes,” she said. “They would do everything right. Sometimes years later it would actually present with a more advanced breast cancer or metastatic breast cancer, which is deadly. It’s no longer curable.”
Breast cancer that has metastasized, or spread to other parts of the body, is stage 4.
The approval has “huge ramifications” for cancer treatment, Lustberg said. It is the first of the “next generation of drugs” targeted for a particular type of cancer, allowing for more personalized medicine, she said. Another, ribociclib, trade name Kisqali, still is under study, she said. They are the “new kids on the block” in cancer treatment, she said.