FDA last week approved a first-of-its-kind late-stage breast cancer treatment that delivers a potent chemotherapy drug directly to cancer cells, leaving healthy cells relatively intact.
The new Roche drug—commercially known as Kadcyla, but known during clinical trials as T-DM1—is among the first drugs in a new class of "antibody-drug conjugates" that deliver a heavy dose of chemotherapy specifically to cancer cells. This targeted approach to chemotherapy—sometimes referred to as "smart bombs"—is less toxic to patients and helps diminish the traditional side effects associated with chemotherapy.
- From the Oncology Roundtable: Our guide to Next-Generation Breast Cancer Strategy.
How the 'smart bombs' work
T-DM1 is the first "smart bomb" designed to treat breast cancer. "Smart bombs" target specific cell types, such as cancer cells, without causing significant damage to other surrounding cells, tissues, and organs.
Specifically, T-DM1 binds Herceptin—the first gene-targeted therapy for breast cancer—to a highly toxic chemotherapy drug called DM1. The two are chemically linked until Herceptin binds to a breast cancer cell, releasing the toxic complement.
In a trial of nearly 1,000 patients, Duke University researchers found that patients with HER2-positive breast cancer lived an average of six months longer when they took Kadcyla than when they followed traditional chemotherapy regimens.
Analysts: Drug approval was wider than expected
Per the FDA, Kadcyla now can be marketed for initial treatment. According to the Wall Street Journal, the approval is broader than expected; analysts though the agency would allow the drug only for patients who have tried other therapies.
With a $9,800 monthly price tag, a typical course of Kadcyla—just over nine months—is estimated to cost $94,000, CNN reports (Hayes, CNN, 2/22; Corbett Dooren, Wall Street Journal, 2/22; AP/USA Today, 2/22; Leuty, San Francisco Business Times, 2/22).