Vaxcyte announces publication of preclinical PoC data of VAX-A1

Vaxcyte announced the publication of preclinical data for VAX-A1, the Company's novel Group A Streptococcus conjugate vaccine candidate, in the journal Infectious Microbes & Diseases. In the study, a novel protein and polysaccharide conjugate of the Group A Strep polysaccharide was constructed for inclusion in a universal subunit vaccine against infections by the pathogen. The study demonstrated that active immunization of mice with the vaccine protected against a Group A Strep challenge in systemic infection and localized skin infection models. Moreover, the antibodies induced by the vaccine bound to a wide array of genetically distinct circulating strains of Group A Strep, without evidence of cross-reactivity to human heart or brain tissue antigens. The study referenced in the paper, "Site-Specific Conjugation of Cell Wall Polyrhamnose to Protein SpyAD Envisioning a Safe Universal Group A Streptococcal Vaccine," was carried out in collaboration with researchers at the Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California School of Medicine and the Skaggs School of Pharmacy and Pharmaceutical Sciences at UC San Diego. Highlights of Findings from the Preclinical Study: The study examined the efficacy of a novel polysaccharide protein conjugate for a vaccine covering all serotypes of Group A Strep. The vaccine elicited antibodies that were protective in systemic and soft tissue mouse models of infection. Broad-based cross-reactivity with multiple M-protein serotypes of Group A Strep was observed in the serum of vaccinated animals. No cross-reactivity was detected with human heart or brain proteins.