Abstract: A nanoparticulate composition for the targeted therapeutic treatment of tumors. The stable self assembled nanocomposition according to the invention comprises (i) a carrier and targeting system comprising an optionally modified polyanion, and optionally a polycation, which may also be modified; at least one targeting agent which is linked to either the polycation/modified polycation or the polyanion/modified polyanion, or both, or to the surface of the nanoparticle; (ii) an active compound selected from the group of doxorubicin and its pharmaceutically acceptable salts, especially hydrochloride; and optionally (iii) at least one complexing agent, a metal ion, a stabilizer/formulating agent, or a PEGylating agent. The present invention furthermore relates to a process for the preparation of the above-mentioned composition, the therapeutic uses thereof, and pharmaceutical compositions containing the nanocomposition according to the invention.