Hydrogel prodrugs

A process for the preparation of a hydrogel comprising the steps of:

• (a) providing a mixture comprising:
• (a-i) at least one backbone reagent, wherein the at least one backbone reagent has a molecular weight ranging from 1 to 100 kDa, and comprises at least three amines (—NH2 and/or —NH—);
• (a-ii) at least one crosslinker reagent, wherein the at least one crosslinker reagent has a molecular weight ranging from 6 to 40 kDa, the at least one crosslinker reagent comprising:
• (i) at least two carbonyloxy groups (—(C═O)—O— or —O—(C═O)—);
• and
• (ii) at least two activated functional end groups selected from the group consisting of activated ester groups, activated carbamate groups, activated carbonate groups and activated thiocarbonate groups;
• wherein the at least one crosslinker reagent is PEG-based comprising at least 70% PEG;
• and
• (a-iii) a first solvent and at least a second solvent, which second solvent is immiscible in the first solvent;
• wherein a weight ratio of the at least one backbone reagent to the at least one crosslinker reagent is in a range of from 1:99 to 99:1;
• and
• (b) polymerizing the mixture of step (a) in a suspension polymerization to a hydrogel.