(CNN) -- A drug that presents a new way to knock out cancer cells was approved Friday to treat patients with a certain type of late-stage metastatic breast cancer. The drug, referred to as T-DM1 during clinical research, will now be known by the brand name Kadcyla, the Food and Drug Administration said in its approval announcement. It's a new therapy for women with HER2-positive breast cancer. Kadcyla is a combination of the targeted drug trastuzumab -- better known by the brand name Herceptin -- and a powerful chemotherapy drug called DM1. It's designed to work when Herceptin alone can no longer keep cancer in check.
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The drug, Kadcyla, presents a new way to knock out cancer cells
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It's meant for some patients with a certain type of metastatic breast cancer
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The drug should be available to patients within two weeks
HER2
The drug is the fourth approved to target the @placeholder protein.
T-DM1
Kadcyla
Kadcyla
DM1
Kadcyla
The estimated cost of a course of @placeholder -- 9Â½ months -- is about $94,000.
HER2
Nearly 20% of breast cancers have increased amounts of @placeholder.
Herceptin
Herceptin
It's important to note, however, that Kadcyla is not the same as @placeholder and could cause serious side effects including liver problems and heart problems such as congestive heart failure or even death.