Clinically proven specification setting for a meningococcal serogroup a conjugate vaccine.

GSK is currently working to improve the commercial presentation of the licensed quadrivalent conjugate vaccine (Menveo) for use against meningococcal serogroup A, C, W, Y (MenACWY) infections. Menveo consists of a primary, lyophilized vial, containing the serogroup A antigen that is reconstituted with the content of a second, liquid, vial that contains the serogroup C, W, Y antigens, to give the final liquid MenACWY product. Since the MenA structure is prone to hydrolytic degradation in liquid formulations, we used mathematical models to rationally design a clinical Phase 2 development plan and provide end of shelf-life (EoSL) and release specification setting for the MenACWY liquid product.

The Preparation and Physicochemical Characterization of Aluminum Hydroxide/TLR7a, a Novel Vaccine Adjuvant Comprising a Small Molecule Adsorbed to Aluminum Hydroxide.

Adjuvants are necessary to enable vaccine development against a significant number of challenging pathogens for which effective vaccines are not available. We engineered a novel small-molecule immune potentiator, a benzonaphthyridine agonist targeting toll-like receptor 7 (TLR7), as a vaccine adjuvant. TLR7 agonist (TLR7a) was engineered to be adsorbed onto aluminum hydroxide (AlOH), and the resulting AlOH/TLR7a was evaluated as a vaccine adjuvant.

Novel adjuvant Alum-TLR7 significantly potentiates immune response to glycoconjugate vaccines.

Although glycoconjugate vaccines are generally very efficacious, there is still a need to improve their efficacy, especially in eliciting a strong primary antibody response. We have recently described a new type of vaccine adjuvant based on a TLR7 agonist adsorbed to alum (Alum-TLR7), which is highly efficacious at enhancing immunogenicity of protein based vaccines. Since no adjuvant has been shown to potentiate the immune response to glycoconjugate vaccines in humans, we investigated if Alum-TLR7 is able to improve immunogenicity of this class of vaccines.

The preparation and characterization of PLG nanoparticles with an entrapped synthetic TLR7 agonist and their preclinical evaluation as adjuvant for an adsorbed DTaP vaccine.

The design of safe and potent adjuvants able to enhance and modulate antigen-specific immunity is of great interest for vaccine research and development. In the present study, negatively charged poly(lactide-co-glycolide) (PLG) nanoparticles have been combined with a synthetic immunepotentiator molecule targeting the Toll-like receptor 7. The selection of appropriate preparation and freeze-drying conditions resulted in a PLG-based adjuvant with well-defined and stable physico-chemical properties.

Rational design of small molecules as vaccine adjuvants.

Adjuvants increase vaccine potency largely by activating innate immunity and promoting inflammation. Limiting the side effects of this inflammation is a major hurdle for adjuvant use in vaccines for humans. It has been difficult to improve on adjuvant safety because of a poor understanding of adjuvant mechanism and the empirical nature of adjuvant discovery and development historically.

Conjugation of a TLR7 agonist and antigen enhances protection in the S. pneumoniae murine infection model.

Next generation vaccine adjuvants include Toll like receptor agonists, which are mostly extracted from microorganisms, but synthetic small molecule TLR agonists have also been identified. However, their delivery systems have not been optimized for effective administration in conjunction with antigens. Here, we describe a novel approach in which a small molecule TLR agonist was directly conjugated to antigen to ensure effective co-delivery.

Aluminum adjuvant dose guidelines in vaccine formulation for preclinical evaluations.

Aluminum (Al) salt-based adjuvants are present in a large variety of licensed vaccines and their use is widely considered for formulations in clinical trials. Although the regulatory agencies have clearly stated the acceptable levels of Al salts in vaccines for human use, there are no general indications for preclinical research. This brief commentary reviews the current status of Al concentrations in licensed vaccines, the related potential toxicity in preclinical species, and proposes a general guideline for selection of suitable Al salt levels in preclinical models, focusing on the formulation development for recombinant protein antigens.

Flow cytometry: an alternative method for direct quantification of antigens adsorbed to aluminum hydroxide adjuvant.

Flow cytometry (FC) has been widely used in biological research; however, its use for vaccine characterization has been very limited. Here we describe the development of an FC method for the direct quantification of two Neisseria meningitidis vaccine antigens, in mono- and multivalent formulations, while still adsorbed on aluminum hydroxide (AH) suspension. The antibody-based method is specific and sensitive.

Identification of MK-5710 ((8aS)-8a-methyl-1,3-dioxo-2-[(1S,2R)-2-phenylcyclo- propyl]-N-(1-phenyl-1H-pyrazol-5-yl)hexahydro-imidazo[1,5-a]pyrazine-7(1H)-carboxamide), a potent smoothened antagonist for use in Hedgehog pathway dependent malignancies, part 2.

The Hedgehog (Hh-) signaling pathway is a key developmental pathway which gets reactivated in many human tumors, and smoothened (Smo) antagonists are emerging as novel agents for the treatment of malignancies dependent on the Hh-pathway, with the most advanced compounds demonstrating encouraging results in initial clinical trials. A novel series of potent bicyclic hydantoin Smo antagonists was reported in the preceding article, these have been resolved, and optimized to identify potent homochiral derivatives with clean off-target profiles and good pharmacokinetic properties in preclinical species. While showing in vivo efficacy in mouse allograft models, unsubstituted bicyclic tetrahydroimidazo[1,5-a]pyrazine-1,3(2H,5H)-diones were shown to epimerize in plasma.

DPP-IV-resistant, long-acting oxyntomodulin derivatives.

Obesity is one of the major risk factors for type 2 diabetes, and the development of agents, that can simultaneously achieve glucose control and weight loss, is being actively pursued. Therapies based on peptide mimetics of the gut hormone glucagon-like peptide 1 (GLP-1) are rapidly gaining favor, due to their ability to increase insulin secretion in a strictly glucose-dependent manner, with little or no risk of hypoglycemia, and to their additional benefit of causing a modest, but durable weight loss. Oxyntomodulin (OXM), a 37-amino acid peptide hormone of the glucagon (GCG) family with dual agonistic activity on both the GLP-1 (GLP1R) and the GCG (GCGR) receptors, has been shown to reduce food intake and body weight in humans, with a lower incidence of treatment-associated nausea than GLP-1 mimetics.

ApoA-I mimetic peptides promote pre-β HDL formation in vivo causing remodeling of HDL and triglyceride accumulation at higher dose.

Reverse cholesterol transport promoted by HDL-apoA-I is an important mechanism of protection against atherosclerosis. We have previously identified apoA-I mimetic peptides by synthesizing analogs of the 22 amino acid apoA-I consensus sequence (apoA-I(cons)) containing non-natural aliphatic amino acids. Here we examined the effect of different aliphatic non-natural amino acids on the structure-activity relationship (SAR) of apoA-I mimetic peptides.

Surface characterization of carbohydrate microarrays.

Carbohydrate microarrays are essential tools to determine the biological function of glycans. Here, we analyze a glycan array by time-of-flight secondary ion mass spectrometry (ToF-SIMS) to gain a better understanding of the physicochemical properties of the individual spots and to improve carbohydrate microarray quality. The carbohydrate microarray is prepared by piezo printing of thiol-terminated sugars onto a maleimide functionalized glass slide.

Determination of carbohydrate-binding preferences of human galectins with carbohydrate microarrays.

Galectins are a class of carbohydrate-binding proteins named for their galactose-binding preference and are involved in a host of processes ranging from homeostasis of organisms to immune responses. As a first step towards correlating the carbohydrate-binding preferences of the different galectins with their biological functions, we determined carbohydrate recognition fine-specificities of galectins with the aid of carbohydrate microarrays. A focused set of oligosaccharides considered relevant to galectins was prepared by chemical synthesis.

Natural Sphingomonas glycolipids vary greatly in their ability to activate natural killer T cells.

Mouse natural killer T (NKT) cells expressing an invariant T cell antigen receptor (TCR) recognize glycosphingolipids (GSLs) from Sphingomonas bacteria. The synthetic antigens previously tested, however, were designed to closely resemble the potent synthetic agonist alpha-galactosyl ceramide (alphaGalCer), which contains a monosaccharide and a C18:0 sphingosine lipid. Some Sphingomonas bacteria, however, also have oligosaccharide-containing GSLs, and they normally synthesize several GSLs with different sphingosine chains including one with a cyclopropyl ring-containing C21:0 (C21cycl) sphingosine.

Effect of tryptophan oligopeptides on the size distribution of POPC liposomes: a dynamic light scattering and turbidimetric study.

A chemical regulation of POPC liposome size distribution was investigated, based on the affinity of indole-containing compounds for phosphocholine membranes. In particular, tryptophan oligopeptides have shown interesting properties of size regulation, both when liposomes were formed in their presence and when the peptides were added to a preformed liposome suspension. Combining dynamic light scattering (DLS) and turbidimetric data, it was possible to show how such peptides had an influence on the size distribution of spontaneously formed liposomes prepared by the thin film hydration, reverse-phase evaporation and ethanol (or methanol) injection methods.

Novel camptothecin analogue (gimatecan)-containing liposomes prepared by the ethanol injection method.

Small-sized liposomes have several advantages as drug delivery systems, and the ethanol injection method is a suitable technique to obtain the spontaneous formation of liposomes having a small average radius. In this paper, we show that liposomal drug formulations can be prepared in situ, by simply injecting a drug-containing lipid(s) organic solution into an aqueous solution. Several parameters should be optimized in order to obtain a final suitable formulation, and this paper is devoted to such an investigation.

Activation and stabilization of alpha-chymotrypsin by cationic additives.

alpha-Chymotrypsin activity was tested with N-glutaryl-l-phenylalanine p-nitroanilide (GPNA) in aqueous media in the presence of synthetic surfactants, which differ in the flexibility of their bulky head groups. Superactivity can be ascribed to the presence of the tributylammonium residue on the surfactant head group, as in p-octyloxybenzyltributylammonium bromide (pOOTBABr), while in the presence of a more rigid moiety, i.e.