A-R. Varasteh, M. Hashemi, M. R. Jaafari, M. Moghadassi Risseh
Anti-D IgG is widely used to prevent hemolytic disease of the newborn. Maintenance of the structural integrity of this therapeutic protein is essential for its efficacy in relation to physiological and pharmacological activities. The aim of this study was to formulate the Anti-D IgG as a parenteral dosage form using suitable buffers and different stabilizing agents. Therefore, after purification, the Anti-D IgG preparation was firstly formulated in different buffers including citrate (pH 4.5), acetate (pH 5.5), and phosphate (pH 6.5 and 7.5) with the concentration of 10, 25, 50 and 100 mM. The formulations were then incubated at 57ºC for 4h and the transmittance was measured at 580 nm. Among the different buffers, the acetate buffer with the concentration of 10 mM had the highest stability effect on the Anti-D IgG. Then, Glycine (Gly), polysorbate 80 and mannitol, in different concentrations were incorporated to the acetate buffer (pH 5.5, 10 mM) containing Anti-D IgG, as stabilizing agents and the stability was investigated as before. Among 16 formulations, the formulation containing Gly, 0.3 M; polysorbate 80, 0.1%; and mannitol 7% had the highest stability. The stability of the formulations was also studied according to British Pharmacopeia (BP) based on bilogical activity. The result indicated that the loss of Anti-D potency of the aforementioned formula is only 9.57 ± ۰٫۲۵% of initial value that meets the requirement set by BP.
Conclusion could be made that this formula could be introduced as a candidate formulation of the Anti-D IgG as a parenteral dosage form.
Keywords: Anti-D, Protein Formulation, IgG stability, Glycine, Polysorbate 80, Mannitol.