Hormone storage stability

Storage stability has generally been the more serious stability issue faced with therapeutic proteins. Storage stability can be extremely formulation-specific [15,30,32,33], and even with a knowledge of the major degradation pathways in solution, selection of the optimum formulation for a solid is far from obvious. We illustrate the sensitivity of stability to formulation details with studies of an important protein product, human growth hormone. 

Figure 5 Effect of excipients on the storage stability of freeze-dried human growth hormone (hGH). Samples were stored for I month at 40°C. Solid bars, aggregation (primarily dimer). Hatched bars, chemical degradation via methionine oxidation and asparagine deamidation. The glass transition temperatures of the initial freeze-dried formulations are given above the bars when a gla.ss transition temperature could be measured by DSC. The glycine mannitol formulation is a weight ratio of hGH glycine mannitol of 1 1 5, the dex-tran formulation is 1 6 hGH dextran 40, none means no stabilizer, and the others are 1 1 hGH stabilizer. All formulations contain sodium phosphate buffer (pH 7.4) at 15% of the hGH content. Initial moisture contents are all ==1%. (Data from [4].)...

Evans MJ, Livesey JH, Ellis MJ, Yandle TG, Effect of anticoagulants and storage temperatures on stability of plasma and serum hormones, Clin. Biochem. 2001 34 107-112. 

K.V. Waite, G.F. Maberly, and C.J. Eastman, Storage conditions and stability of thyrotropin and thyroid hormones on filter paper, Clinical Chemistry 33(6) 853-855(1987). 

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