Study freeze-dried of bevacizumab and labeling with 99mTc for tumor radioimmunoscintigraphy

Abstract

Objective: Bevacizumab, a humanized monoclonal antibody against VEGF was lyophilized and labeled with radioisotope 99mTc using in tumor radioimmunoscintigraphy. The purpose of the study is to develop a formulation and process for lyophilization of bevacizumab.
Methods: Bevacizumab was studied on the lyophilization at the difference of buffers, pH, temperature and time. The antibody lyophilized compound was tested on the stable with time, radiolabeled with 99mTc radioisotope, radiochemical purity examination and stability of radioimmunoconjugates.
Results: The results of the study showed that bevacizumab was lyophilized to form a white porous dry form under optimal conditions, as a phosphate buffer 0.5 M, pH 7.4 at - 40°C and a time of 24 hours. The lyophilized bevacizumab was stable after 6 months of follow-up. Radiochemical purity of 99mTc-bevacizumab has been reached more than 98% and passed the test for sterility, bacterial endotoxin.
Conclusion: Bevacizumab was prepared in a lyophilized formulation, can be used for radiolabeling with 99mTc, which met radiopharmaceutical
criteria, and could be used in preclinical evaluations.