Development of a SARS Coronavirus Vaccine from Recombinant Spike Protein Plus Delta Inulin Adjuvant.

Given periodic outbreaks of fatal human infections caused by coronaviruses, development of an optimal coronavirus vaccine platform capable of rapid production is an ongoing priority. This chapter describes the use of an insect cell expression system for rapid production of a recombinant vaccine against severe acute respiratory syndrome coronavirus (SARS). Detailed methods are presented for expression, purification, and release testing of SARS recombinant spike protein antigen, followed by adjuvant formulation and animal testing. The methods herein described for rapid development of a highly protective SARS vaccine are equally suited to rapid development of vaccines against other fatal human coronavirus infections, e.g., the MERS coronavirus.

Improved stability of recombinant hemagglutinin using a formulation containing sodium thioglycolate.

This study was designed to improve the stability of liquid formulations of recombinant influenza hemagglutinin (rHA) and to understand the mechanism of early loss of potency for rHA. The potency of rHA derived from several influenza strains was determined using single radial immunodiffusion (SRID), and the structure of the rHA was characterized using SDS-PAGE and dynamic light scattering. rHA formed disulfide cross-linked multimers, and potency decreased during extended storage. To reduce disulfide-mediated cross-linking and early potency loss, rHA was formulated with sodium thioglycolate (STG) and citrate. Addition of 80 mM STG and 55 mM sodium citrate inhibited disulfide-mediated cross-linking without affecting protein function for each rHA tested. The shelf life of the rHA formulation with STG-citrate, based on potency as determined by SRID, was extended as much as 20-fold, compared to a control formulation without STG-citrate. STG-citrate did not have a significant effect on the immunogenicity of H1 A/California/7/2009 rHA in mice.

Technology transfer and scale-up of the Flublok recombinant hemagglutinin (HA) influenza vaccine manufacturing process.

Multiple different hemagglutinin (HA) protein antigens have been reproducibly manufactured at the 650L scale by Protein Sciences Corporation (PSC) based on an insect cell culture with baculovirus infection. Significantly, these HA protein antigens were produced by the same Universal Manufacturing process as described in the biological license application (BLA) for the first recombinant influenza vaccine approved by the FDA (Flublok). The technology is uniquely designed so that a change in vaccine composition can be readily accommodated from one HA protein antigen to another one. Here we present a vaccine candidate to combat the recently emerged H7N9 virus as an example starting with the genetic sequence for the required HA, creation of the baculovirus and ending with purified protein antigen (or vaccine component) at the 10L scale accomplished within 38 days under GMP conditions. The same process performance is being achieved at the 2L, 10L, 100L, 650L and 2500L scale. An illustration is given of how the technology was transferred from the benchmark 650L scale facility to a retrofitted microbial facility at the 2500L scale within 100 days which includes the time for facility engineering changes. The successful development, technology transfer and scale-up of the Flublok process has major implications for being ready to make vaccine rapidly on a worldwide scale as a defense against pandemic influenza. The technology described does not have the same vulnerability to mutations in the egg adapted strain, and resulting loss in vaccine efficacy, faced by egg based manufacture.