Abstract: Stable pharmaceutical compositions suitable for parenteral administration to animals or humans are prepared comprising a therapeutically effective amount of a recombinant IFN-.beta. protein dissolved in an inert carrier medium comprising as solubilizer/stabilizer(s) one or more biocompatible non-ionic polymeric detergents or a combination of one or more biocompatible non-ionic polymeric detergents with an additional solubilizing and/or stabilizing agent, such as sodium dodecyl sulfate or glycerol. The compositions are in liquid form or lyophilized.

Abstract: Stable pharmaceutical compositions suitable for parenteral administration to mammals are prepared which are in a pH range of about 2 to about 4 and comprise a therapeutically effective amount of a recombinant interferon-.beta. protein (IFN-.beta.) dissolved in an inert carrier medium comprising as a stabilizer/solubilizer an effective amount either of glycerol or of polyethylene glycol polymers having an average molecular weight from about 190 to about 1600 daltons. Further disclosed and claimed are methods for extracting IFN-.beta. from a microbial host transformed to produce it and then purifying and formulating said IFN-.beta. and methods for screening for other polyhydric non-detergent stabilizer/solubilizers or combinations thereof as solubilizer/stabilizers for pharmaceutical compositions of IFN-.beta..

Abstract: An approved procedure for the purification and renaturation of biologically active, bacterially produced IFN-.beta. is described. The partially purified material obtained by solubilization of isolated refractile bodies from the recombinant cells is treated to obtain reduction of the protein in the presence of a chaotropic environment and then oxidized after removal of the reducing agent. However, the chaotropic environment is retained during the oxidation. Upon removal of the chaotropic environment, a solubilizing additive is supplied to maintain the IFN-.beta. in solution. Further purification by conventional means may also be effected.