The present invention relates to a hydroxyalkyl starch conjugate and a method for preparing the same, said hydroxy-yalkyl starch conjugate comprising a hydroxyalkyl starch derivative and a cytotoxic agent, the cytotoxic agent comprising at least one secondary hydroxyl group, wherein the hydroxyalkyl starch is linked via said secondary hydroxyl group to the cytotoxic agent. The conjugate according to the present invention has a structure according to the following formula HAS′(-L-M)n wherein M is a residue of the cytotoxic agent, L is a linking moiety, HAS′ is the residue of the hydroxyalkyl starch derivative, and n is greater than or equal to 1, and wherein the hydroxyalkyl starch derivative has a mean molecular weight (MW) above the renal threshold.
