Developing recombinant protein pharmaceuticals has proved to be very challenging because of both the complexity of protein production and purification, and the limited physical and chemical stability of proteins. The most commonly used method for preparing improved shelf life solid protein pharmaceuticals is lyophilization.We propose to use OSIRIS to perform measurements on lysozyme, disaccharides (trehalose and sucrose) and lysozyme/disaccharide (trehalose, sucrose) mixtures in their lyophilised form at T=100K, T=300K and T=450K. This study will allow i) to determine the effects of the different degree of amorphisation, in particular comparing lysozyme and lysozyme/trehalose mixtures; ii) to evaluate the effects of trehalose on the stability of lysozyme, which otherwise would denature (at T=428K); iii) to establish the role of trehalose in contrasting the temperature effects.