| abstract |
The present invention describes a method for conjugating a cell binding agent, such as an antibody, to an effector group (eg, cytotoxic agent) or reporter group (eg, radionuclide), wherein the reporter or effector group is first isolated. It is reacted with the soluble linker and the mixture is then used for conjugation reaction with the cell binder without purification. The methods described herein are advantageous for the preparation of stably-linked conjugates of cell binders, such as antibodies, and effector or reporter groups. This conjugation method provides a high yield of high purity and homogeneous conjugates free of cross-chain crosslinking and inactivated linker residues in high yield. |