In conclusion, overlapping yet distinct pharmacological properties of ranibizumab and bevacizumab indicate that safety or efficacy data from one cannot be extrapolated to the other. and properties and preclinical safety data. Materials and methods This review was based on a literature search performed in http://PubMed.gov using two separate searches. cell functioning. Compared with bevacizumab, ranibizumab neutralizes VEGF better at low concentrations, maintains efficacy for longer, and has a higher retinal penetration and potency. Studies in animals demonstrate ranibizumab to be better localized to the injected eye, whereas bevacizumab appears to have a greater effect in the fellow eye. In humans, a localized and systemic effect has been reported for both molecules. In conclusion, overlapping yet distinct pharmacological properties of ranibizumab and bevacizumab indicate that safety or efficacy data from one cannot be extrapolated to the other. and properties and preclinical safety data. Materials and methods This review was based on a literature search performed in http://PubMed.gov using two separate searches. The first search used the terms ranibizumab’ and age-related macular degeneration’. The second search used the terms bevacizumab’ and age-related macular degeneration’. The review focussed upon, but was not limited to, pre-clinical studies in English language retrieved using these criteria. Additional studies, which were deemed relevant to the topic of this review, were also considered for inclusion. Ranibizumab and bevacizumab generation and characteristics Ranibizumab is a Fab of an antibody that was developed as part of an anti-VEGF program in AMD.10 Bevacizumab is a full-length antibody that was developed as a potential therapeutic agent for use in oncology.20 Both ranibizumab and bevacizumab were constructed from the mouse anti-human VEGF monoclonal antibody (mAb) A.4.6.1, which was produced using Chiglitazar hybridoma generated from mice immunized with the predominant VEGF165 isoform conjugated to keyhole limpet hemocyanin. This murine mAb has been shown to recognize all VEGF-A isoforms and inhibit the growth of human tumor cell lines CDR mutation and affinity selection from a different humanized anti-VEGF Fab variant, known as MB1.6.26, 27 Ranibizumab is produced as a 48?kDa Fab in from the expression plasmid pY0317. The heavy and light chains fold into their native confirmation following secretion into the Chiglitazar bacteria periplasmic space and are covalently linked. The resulting Fab-Y0317 is now known as ranibizumab.10, 25, 28 A schematic diagram of ranibizumab VEZF1 and bevacizumab generation is depicted in Figure 1. Open in a separate window Figure 1 Schematic diagram of ranibizumab and bevacizumab generation. CH, constant heavy domain; CL, constant light domain; VH, variable heavy domain; VL, variable light domain; CDR, complimentarity determining region; Fab, fragment antigen Chiglitazar binding; Fc, fragment crystallizable. studies of ranibizumab and bevacizumab Ranibizumab and bevacizumab are both able to bind to all human VEGF-A isoforms.10, 20 Following its generation from Fab-12, bevacizumab was found to inhibit VEGF-induced proliferation of endothelial cells and tumor growth with potency and efficacy similar to those of the parent murine antibody A.184.108.40.206 Ranibizumab (Fab-Y0317) demonstrated a 22-fold improvement in binding affinity over Fab-12 in VEGF competition assays and had 120- to 140-fold improved affinity over Fab-12 in kinetic experiments.10, 25 Furthermore, ranibizumab had a 30- to 100-fold increased potency in bioassays measuring VEGF-induced endothelial cell mitogenesis. On a molar basis, ranibizumab was determined to be 5- to 20-fold more potent than full-length bevacizumab at binding VEGF-A.10, 25 The characteristic properties of ranibizumab and bevacizumab are summarized in Table 1 . Table 1 Characteristic properties of ranibizumab and bevacizumab Fab-12. The majority of studies investigating the efficacy of ranibizumab and bevacizumab were performed in 2006 or later. Before 2009, most of the studies were related to the short-term toxicity of bevacizumab in multiple cell types of the eye. In 2006, the Bevacizumab Study Group demonstrated no significant short-term effects of bevacizumab on retinal function of isolated bovine retina,.