The composition comprises a dispersion of nanocorpuscles in an aqueous solution as a dispersant and a pharmaceutically acceptable alcohol as co-dispersant or cosolvent, said nanocorpuscles having at least one lipid bilayer comprising at least one biliar salt, e.g. sodium cholate, and at least one phospholipid, e.g. soy lecitine; these nanocorpuscles having an average diameter lower than 500 nm; and including metallothioneine in their interior. The process for obtaining the particles comprises: a) prepare an aqueous solution of at least one biliar salt and metallothioneine; b) prepare an alcoholic solution of the phospholipid; c) jointly homogenise both solutions. This pharmaceutical composition can be used as a medicament, particularly in the treatment of neurodegenerative and neurological disorders, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, etc.