A safety and immunogenicity study of immunization with hVEGF26-104/RFASE in cynomolgus monkeys. Issue 15 (5th April 2018)

• Record Type: Journal Article
• Authors: Wentink, Madelon Q.; Verheul, Henk M.W.; Griffioen, Arjan W.; Schafer, Kenneth A.; McPherson, Susan; Early, Richard J.; van der Vliet, Hans J.; de Gruijl, Tanja D.
• Is Part Of: Vaccine. Volume 36:Issue 15(2018)
• Page Start: 2025
• Page End: 2032
• Publication Date: 2018-04-05
• Subjects: VEGF -- Vaccine -- Angiogenesis -- Antibodies -- Cynomolgus monkeys; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2018.02.066
• Languages: English
• ISSNs: 0264-410X

Abstract

Abstract: Introduction: Vascular endothelial growth factor (VEGF) is pivotal in tumor angiogenesis and therapies targeting the VEGF axis are widely used in the clinic for the treatment of cancer. We have developed a therapeutic vaccine targeting human (h)VEGF165 . hVEGF26-104 /RFASE is based on the truncated protein hVEGF26-104 as antigen formulated in an oil-in-water emulsion containing the sulpholipopolysaccharide RFASE as adjuvant. Here we describe the toxicity and immunogenicity of this therapeutic vaccine in cynomolgus monkeys. Methods: In total 54 cynomolgus monkeys were used and divided in 7 groups. Groups 1–3 were control groups, either receiving PBS alone (group 1), RFASE alone (group 2) or hVEGF26-104 alone (group 3). Animals allocated to groups 4–7 received hVEGF26-104 together with RFASE, but with varying doses of the antigen or the adjuvant. All animals were immunized four times with 2-week intervals and safety and immunogenicity were monitored until 3 days after the final immunization. Results: Immunization induced an RFASE adjuvant dependent acute phase response. High titers of antibodies against hVEGF26-104 and cross-reactive with hVEGF165, were found in monkey sera, 28 days after primer immunization. These antibodies were able to inhibit the binding of the monoclonal antibody bevacizumab with hVEGF165 in a competition ELISA. Moreover, the biological activity of hVEGF165 could be inhibited by the addition of immunized monkey serum in a VEGF specific bioassay. Importantly, no adverse events commonly observed with VEGF neutralization were observed throughout the study. Conclusion: These data show that hVEGF26-104 /RFASE can be safely administered in cynomolgus monkeys, induces the desired immune response and therefore support the clinical development of this vaccine.