FDA warns of medication error BC drug

When I first heard that this emtansine that is added to Herceptin to make T-DM1, I was wondering if this was the incredibly potent poison that was far toxic to be used in people, at least when given in a typical intravenous infusion.

Research To Practice initially stated T-DM1 as trastuzumab maytansine, not emtansine. In an article last September in Medical News Today, it stated T-DM1 contains a chemotherapy agent (maytansine) stably connected to Herceptin. And Dr. Len at ACS thought is was maytansine, not emtansine.

Maytansine was a drug evaluated in the 1970's and found to be effective in treating breast cancer, but its side effects were so severe that it could not be used clinically. As a result, it became a laboratory curiosity, banned from patient care. It is a maytansine derivative, not maytansine.

I can see why the FDA issued the new warning about using the generic name for Kadcyla that may lead to the treatment being confused with an older therapy and cause potential harm to patients. They were required to call it ado-trastuzumab emtansine and not trastuzumab emtansine.

I understand the manufacturer developed a new packaging for Kadcyla to further differentiate it from Herceptin. Physicians should use both the brand name and generic name while communicating medication orders.