Study: Breast Cancer Drug Could Have Wider Use

A drug used to fight breast cancer may be effective against other forms of the disease, according to a new study.

Writing in the journal JAMA Oncology, researchers from the Abramson Cancer Center (ACC) in the University of Pennsylvania, say that after reviewing existing literature and doing their own research, palbociclib could attack other types of cancer cells while inflicting little or no harm to healthy cells.

Palbociclib is a CDK4/6 inhibitor, meaning it targets certain enzymes that drive rapid tumor cell division. It was the first such drug approved against breast cancer.

"All living cells undergo cell division and palbociclib's unique capacity to halt the cell division process (also known as the 'cell cycle') therefore has potentially broad applicability," said lead author Amy S. Clark, MD, MSCE, an assistant professor of Hematology/Oncology at Penn's Perelman School of Medicine and ACC. "Pairing palbociclib with other anti-cancer therapies such as endocrine therapy, chemotherapy, and targeted therapy can create a powerful combinatorial effect with real promise for addressing a variety of cancers."

The researchers say the drug has shown promise against lymphoma, sarcoma, and teratoma, which are relatively rare, but often strike young people.

In a phase 2 trial, the drug was used on 17 patients with mantle-cell lymphoma. One patient had a “complete response,” meaning the cancer disappeared for at least some time, while two others had “partial responses.” The drug also appeared to improve survival times among patients with the disease.

Furthermore, researchers said that in other cancer trials, the drug “has been shown to be safe with once-daily dosing,” with the main side effect being lower counts of a certain type of white blood cells that fight infection. That, researchers say, can be reversed by temporarily stopping the drug, then later resuming treatment at a lower dose.