Don't confuse Kadcyla with Herceptin, FDA says

The FDA is picky about drug names. It's been known to reject brand monikers because they're too similar to others already out there in the market, worried that harried physicians and pharmacists might accidentally give patients the wrong one.

But this time, the FDA is warning patients and doctors about generic-name confusion. Two Roche ($RHHBY) cancer drugs--the longtime standard-bearer Herceptin and the brand-new Kadcyla-- have similar generic names. That's not too surprising; after all, Kadcyla is an amped-up, "armed antibody" offshoot of the earlier drug. So, Herceptin is trastuzumab, and Kadcyla is ado-trastuzumab emtansine.

Problem is, some drug compendia, websites and electronic health systems have been truncating Kadcyla's name, leaving off that all-important "ado-"--which is, of course, the only syllable separating its first name from Herceptin's full one. And designating Kadcyla as trastuzumab emtansine can mislead people into mistaking it for trastuzumab, period, the FDA says.

"The dosing and treatment schedules for Kadcyla and Herceptin, another breast cancer drug, are quite different, so confusion between these products could lead to dosing errors and potential harm to patients," the FDA said in a statement. No medication errors have been reported to FDA since Kadcyla's approval in February, the agency said.

Roche tells Reuters it discussed the risk of name confusion with the FDA during the agency's review of Kadcyla's application. "To help reduce future risk, the FDA requested that we add a prefix ("ado") to the generic name for Kadcyla," Roche told the news service. The company also developed new packaging for Kadcyla to distinguish it from Herceptin.

FDA is warning healthcare professionals to use both of Kadcyla's official names: the brand name and the full non-proprietary name, ado-trastuzumab emtansine. Medication orders, preprinted order sets, computerized order entry systems and so on should all use both names, the agency said.

- read the FDA statement
- see the Reuters news

Read more on