Interferon-beta formulations HSA-free

A stabilized pharmaceutical composition free of HSA comprising interferon-beta (IFN-β) substantially monomer or a biologically active variant of this solubilised in a formulation of low ionic strength, wherein said formulation of low ionic concentration is a solution comprising a buffer in an amount sufficient to maintain the pH of said composition within plus or minus 0.5 pH units of a specified pH, where the specified is about 3.0 to about 5.0, said formulation having an ionic strength amount not greater than about 20 mM.