The invention relates to a sustained drug release nanocomposite, comprising a) a charge carrying core of primary protein particles reversibly precipitated in an ionic procedure from solutions containing at least one cytokine drug and b) a polyelectrolyte shell comprised of 3 to 5 alternate layers of two oppositely charged polyelectrolytes, the dissociation state of one of the polyelectrolytes being varied with pH of the aqueous medium while the other polyelectrolyte is fully dissociated, irrespective of the pH of the medium. There is also provided a process for producing the said nanocomposite and the use of the same for producing sustained release drug formulations.
