Towards achieving the goal of eliminating epidemic outbreaks of meningococcal disease in the African meningitis belt, a pentavalent glycoconjugate vaccine (NmCV-5) has been developed to protect against Neisseria meningitidis serogroups A, C, Y, W and X. MenA and X polysaccharides are conjugated to tetanus toxoid (TT) while MenC, Y and W polysaccharides are conjugated to recombinant cross reactive material 197 (rCRM₁₉₇), a non-toxic genetic variant of diphtheria toxin. This study describes quality control testing performed by the manufacturer, Serum Institute of India Private Limited (SIIPL), and the independent control laboratory of the U.K. (NIBSC) on seven clinical lots of the vaccine to ensure its potency, purity, safety and consistency of its manufacturing. In addition to monitoring upstream-manufactured components, samples of drug substance, final drug product and stability samples were evaluated. This paper focuses on the comparison of the vaccine’s critical quality attributes and reviews key indicators of its stability and immunogenicity. Comparable results were obtained by the two laboratories demonstrating sufficient levels of polysaccharide O-acetylation, consistency in size of the bulk conjugate molecules, integrity of the conjugated saccharides in the drug substance and drug product, and acceptable endotoxin content in the final drug product. The freeze-dried vaccine in 5-dose vials was stable based on molecular sizing and free saccharide assays. Lot-to-lot manufacturing consistency was also demonstrated in preclinical studies for polysaccharide-specific IgG and complement-dependent serum bactericidal activity for each serogroup. This study demonstrates the high quality and stability of NmCV-5, which is now undergoing Phase 3 clinical trials in Africa and India.

Background/Objective: Apart from the attributes such as cost, yields and consistency that define the feasibility of a manufacturing process, physicochemical and immunological quality traits equally signify the functionality of a biological product. The present study investigates one such promising Meningococcal B vaccine candidate, a chimeric fHbp-PorA protein in Escherichia coli. Methods: The chimeric fHbp–PorA protein, expressed with an N-terminal tag of HIS-MBP-TEV was produced in a 10 L fermenter under two different media and induction strategies: chemically defined (CD) media with lactose induction and complex media (CM) with galactose-mediated autoinduction. Comparative analysis was carried out between the two approaches for cell growth, protein expression, and purification, and the final chimeric proteins were characterized to evaluate for their biochemical, structural, in vitro and in vivo immunochemical properties. Results: Growth in the CD media resulted in several-fold-higher biomass compared to that in CM media in a short cultivation time; however, more than a third of the expressed protein remained in an insoluble state. Meanwhile, almost all of the expressed protein with CM media was recovered in soluble form. Moreover, purification of the unprocessed tagged protein and recovery of chimeric protein (tag removed) resulted in 75% greater yield in CM media when compared to CD media. The final chimeric proteins obtained from each medium varied significantly in their physicochemical characteristics, including their epitope projection and CD spectra. The results of in vivo animal immunogenicity response also showed higher serum bactericidal activity associated with chimeric protein obtained from CM media compared to CD media. Conclusions: The outcomes demonstrate that complex media with galactose-induced expression not only show higher productivity but also exhibit superior quality attributes, qualifying their reliable use in the manufacturing process of this promising vaccine candidate.

There is current interest in the group A streptococcal carbohydrate as a vaccine antigen, and previous studies have suggested that it may induce host tissue cross-reactive autoantibodies which react with heart and brain autoantigens and which are present in streptococcal sequelae, including rheumatic heart disease, Sydenham chorea, and pediatric autoimmune neuropsychiatric disorder associated with streptococci (PANDAS)