Therapeutic dendrimer

A dendrimer comprising:

• i) a core unit (C) which is
• and
• ii) building units (BU), which are
• wherein the acyl group of each building unit provides a covalent attachment point for attachment to the core or to a previous generation building unit;
• and wherein each nitrogen atom provides a covalent attachment point for covalent attachment to a subsequent generation building unit, a first terminal group or a second terminal group;
• wherein the core unit is covalently attached to two building units via amide linkages, each amide linkage being formed between a nitrogen atom present in the core unit and the carbon atom of an acyl group present in a building unit;
• the dendrimer being a five generation building unit dendrimer;
• wherein building units of different generations are covalently attached to one another via amide linkages formed between a nitrogen atom present in one building unit and the carbon atom of an acyl group present in another building unit;
• the dendrimer further comprising:
• iii) a plurality of first terminal groups (T1) each comprising a residue of a nucleoside analogue, which nucleoside analogue has a hydroxyl group, covalently attached to a diacyl linker group of formula:
• and
• iv) a plurality of second terminal groups (T2) each comprising a hydrophilic polymeric group which is a polyethylene glycol (PEG) group;
• or
• a pharmaceutically acceptable salt thereof.