Cytotoxic agents comprising maytansinoids and their therapeutic use

Abstract

A cytotoxic agent comprising one or more maytansinoids linked to a cell binding agent. A therapeutic agent for killing selected cell populations comprising: (a) a cytotoxic amount of one or more maytansinoids linked to a cell binding agent, and (b) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting a cell population or tissue suspected of containing cells from said selected cell population with a cytotoxic amount of a cytotoxic agent comprising one or more maytansinoids linked to a cell binding agent. An N-methyl-alanine-containing ester of maytansinol or an analogue of maytansinol, said N-methyl-alanine-containing ester comprising a linking group capable of linking an N-methyl-alanine-containing maytansinoid ester to a chemical moiety. N-methyl-cysteine-containing ester of maytansinol or an analogue of maytansinol.

Dependencies are inferred from the claim text.