The invention relates to a method for obtaining formulations which improve the binding capacity of siRNAs in relation to plasma components, which promote the transport of siRNA in the blood, which increase the passage of siRNA through the cell membrane and, consequently, which increase the inhibitory activity of siRNA. The invention also relates to a method for obtaining a formulation comprising siRNA associated with plasma components, characterised in that the method includes a step in which the plasma components are dispersed in an aqueous medium.
