Physicochemical evaluation of lyophilized formulation of p-SCN-Bn-DOTA- and p-SCN-Bn-DTPA-rituximab for NHL radio immunotherapy

Radioimmunotherapy (rit) of non-hodgkin’s lymphoma (nhl) is said to be more advantageous compared to unlabelled therapeutic antibodies. to this date,radiolabelled murine anti-cd20 mabs,zevalin� and bexxar� have been approved for imaging and therapy. a preparation containing rituximab,chimeric mab radio immunoconjugate suitable for lu-177 labeling,could provide better imaging and therapeutic profile at the same time. this study was conducted to evaluate prepared lyophilized formulations of two rituximab immune conjugates,intended for immediate lu-177 labeling,for imaging and therapy. the characterization of the conjugates and demonstration of the integrity of the protein and purity after conjugation and lyophilization was performed by sds-page,ft-ir and maldi-tof-ms. the results showed preserved antibody structure and average of 6.1 p-scn-bn- dota and 8.8 p-scn-bn-dtpa groups per antibody molecule which is suitable for successful labeling. these results support the possibility of developing a “ready-to-label” rituximab immune conjugates for nhl imaging/therapy. � 2016 by school of pharmacy.