This invention relates to novel conjugates of the DNA-alkylating agent CC-1065. The conjugates are designed to release their (multiple) payload after one or more activation steps and/or at a rate and time span controlled by the conjugate in order to selectively deliver and/or controllably release one or more of said DNA alkylating agents. The conjugates can be used to treat an illness that is characterized by undesired (cell) proliferation. As an example, the conjugates of this invention may be used to treat a tumor.
