METHOD FOR PREPARING MAYTANSINOID-ANTIBODY CONJUGATE

摘要

PROBLEM TO BE SOLVED: To provide a method for preparing a conjugate comprising a cell binding agent chemically conjugated to a drug and having sufficiently high purity and stability.SOLUTION: A method for preparing an antibody-maytansinoid conjugate comprises the steps of: contacting an antibody with a bifunctional crosslinking reagent to covalently attach a linker to the antibody thereby to prepare a first mixture containing the antibody having a linker bound thereto; conjugating maytansinoid to the antibody having the linker bound thereto in the first mixture by reacting the first mixture with maytansinoid in a solution of pH4-9 to prepare a second mixture containing the antibody chemically coupled to maytansinoid through the linker, free maytansinoid and reaction by-products; and purifying the antibody chemically coupled to maytansinoid from the second mixture, with the proviso that the first mixture is not subjected to purification.