Optimizing immunogenicity and product presentation of a SARS-CoV-2 subunit vaccine composition: effects of delivery route, heterologous regimens with self-amplifying RNA vaccines, and lyophilization.

Introduction: Dozens of vaccines have been approved or authorized internationally in response to the ongoing SARS-CoV-2 pandemic, covering a range of modalities and routes of delivery. For example, mucosal delivery of vaccines via the intranasal (i.n.

Concordance of in vitro and in vivo measures of non-replicating rotavirus vaccine potency.

Rotavirus infections remain a leading cause of morbidity and mortality among infants residing in low- and middle-income countries. To address the large need for protection from this vaccine-preventable disease we are developing a trivalent subunit rotavirus vaccine which is currently being evaluated in a multinational Phase 3 clinical trial for prevention of serious rotavirus gastroenteritis. Currently, there are no universally accepted in vivo or in vitro models that allow for correlation of field efficacy to an immune response against serious rotavirus gastroenteritis.

Animal testing for vaccines. Implementing replacement, reduction and refinement: challenges and priorities.

Transition to in vitro alternative methods from in vivo in vaccine release testing and characterization, the implementation of the consistency approach, and a drive towards international harmonization of regulatory requirements are most pressing needs in the field of vaccines. It is critical for global vaccine community to work together to secure effective progress towards animal welfare and to ensure that vaccines of ever higher quality can reach the populations in need in the shortest possible timeframe. Advancements in the field, case studies, and experiences from Low and Middle Income Countries (LMIC) were the topics discussed by an international gathering of experts during a recent conference titled "Animal Testing for Vaccines - Implementing Replacement, Reduction and Refinement: Challenges and Priorities".

Effect of Aluminum Adjuvant and Preservatives on Structural Integrity and Physicochemical Stability Profiles of Three Recombinant Subunit Rotavirus Vaccine Antigens.

A nonreplicating rotavirus vaccine (NRRV) containing 3 recombinant fusion proteins adsorbed to aluminum adjuvant (Alhydrogel [AH]) is currently in clinical trials. The compatibility and stability of monovalent NRRV antigen with key components of a multidose vaccine formulation were examined using physicochemical and immunochemical methods. The extent and strength of antigen-adjuvant binding were diminished by increasing phosphate concentration, and acceptable levels were identified along with alternate buffering agents.