A cytotoxic agent comprising one or more taxanes linked to a cell binding agent.
A therapeutic composition for killing selected cell populations comprising: (A)
a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent
through a linking group, and (B) a pharmaceutically acceptable carrier, diluent
or excipient. A method for killing selected cell populations comprising contacting
target cells or tissue containing target cells with an effective amount of a cytotoxic
agent comprising one or more taxanes linked to a cell binding agent. Novel sulfur-containing taxanes.