Patent attributes
The invention relates to the discovery that the addition of aromatic carboxylate ions inhibit protein instability caused by aromatic preservatives. Thus, the invention relates to compositions, preferably aqueous compositions, comprising a protein, an aromatic preservative and aromatic carboxylate ions. The proteins remain stable and suitable for storage at ambient temperatures or lower, even in aqueous form. Preferably, the aqueous composition comprises a protein, a phenolic preservative and benzoate ions, wherein the pH of the composition is at least 1 unit greater than the pKa of benzoic acid. The invention also provides methods of reducing protein degradation by aromatic preservatives in an aqueous formulation of a protein susceptible to such degradation, comprising the step of adding aromatic carboxylate ions to the formulation wherein the formulation is maintained at a pH that is at least 1 unit greater than the pKa of the corresponding aromatic carboxylic acid.