Chikungunya virus virus-like particle vaccine is well tolerated and immunogenic in chikungunya seropositive individuals.

In a phase 2 safety and immunogenicity study of a chikungunya virus virus-like particle (CHIKV VLP) vaccine in an endemic region, of 400 total participants, 78 were found to be focus reduction neutralizing antibody seropositive at vaccination despite being ELISA seronegative at screening, of which 39 received vaccine. This post hoc analysis compared safety and immunogenicity of CHIKV VLP vaccine in seropositive (n = 39) versus seronegative (n = 155) vaccine recipients for 72 weeks post-vaccination. There were no differences in solicited adverse events, except injection site swelling in 10.

Safety and immunogenicity of PXVX0317, an aluminium hydroxide-adjuvanted chikungunya virus-like particle vaccine: a randomised, double-blind, parallel-group, phase 2 trial.

Background: Chikungunya virus (CHIKV) disease is an ongoing public health threat. We aimed to evaluate the safety and immunogenicity of PXVX0317, an aluminium hydroxide-adjuvanted formulation of a CHIKV virus-like particle (VLP) vaccine.

Methods: This randomised, double-blind, parallel-group, phase 2 trial was conducted at three clinical trial centres in the USA.

Exposure-Response Modeling and Simulation to Support Human Dosing of Botulism Antitoxin Heptavalent Product.

Botulism antitoxin heptavalent (A, B, C, D, E, F, and G - Equine; BAT) product is a sterile solution of F(ab') and F(ab') -related antibody fragments prepared from plasma obtained from horses that have been immunized with a specific serotype of botulinum toxoid and toxin. BAT product is indicated for the treatment of symptomatic botulism following documented or suspected exposure to botulinum neurotoxin serotypes A to G in adults and pediatric patients. Pharmacokinetic and exposure-response models were used to explore the relationship between BAT product exposure and the probability of survival, and the occurrence of relevant moderate clinical signs observed during the preclinical development of BAT product to justify the clinical dose.

Use of Botulism Antitoxin Heptavalent (A, B, C, D, E, F, G)-(Equine) (BAT) in Clinical Study Subjects and Patients: A 15-Year Systematic Safety Review.

Botulism is a rare, sometimes fatal paralytic illness caused by botulinum neurotoxins. BAT (Botulism Antitoxin Heptavalent (A, B, C, D, E, F, G)-(Equine)) is an equine-derived heptavalent botulinum antitoxin indicated for the treatment of symptomatic botulism in adult and pediatric patients. This review assesses the cumulative safety profile for BAT product from 2006 to 2020, using data received from clinical studies, an expanded-access program, a post-licensure registry, spontaneous and literature reports.

Results of a Double-Blind, Randomized, Placebo-Controlled Phase 1 Study to Evaluate the Safety and Pharmacokinetics of Anti-Zika Virus Immunoglobulin.

Zika virus (ZIKV) is transmitted primarily through infected Aedes aegypti or Aedes albopictus mosquitoes. ZIKV infection during pregnancy was linked to adverse fetal/infant outcomes, including microcephaly, brain anomalies, ocular disorders, intrauterine growth restriction, and other congenital malformations. Human anti-Zika virus immunoglobulin (ZIKV-Ig) is being developed for prophylaxis of ZIKV in at-risk populations, including women of childbearing potential and pregnant women.

Cost savings associated with timely treatment of botulism with botulism antitoxin heptavalent product.

Background: Botulism is a rare, serious, and sometimes fatal paralytic illness caused by exposure to neurotoxins produced by Clostridium botulinum bacteria. Patients with documented or suspected exposure to botulinum toxin serotypes A-G can be treated with BAT® [Botulism Antitoxin Heptavalent (A, B, C, D, E, F, G)-(Equine)] product, which was approved in 2013 in the United States (US). Patients with botulism have demonstrated greater clinical benefit with early BAT product treatment (≤2 days from symptom onset) versus late treatment (>2 days).

Safety and Clinical Outcomes of an Equine-derived Heptavalent Botulinum Antitoxin Treatment for Confirmed or Suspected Botulism in the United States.

Background: Botulism is a rare, life-threatening paralytic illness. Botulism Antitoxin Heptavalent (A,B,C,D,E,F,G)-(Equine) (BAT) manufactured by Emergent BioSolutions Canada Inc is an equine-derived heptavalent botulinum antitoxin product indicated for the treatment of symptomatic botulism following documented or suspected exposure to botulinum neurotoxin serotypes A-G in adults and pediatric patients. BAT product was US-licensed in 2013.

Adenovirus-Vectored Vaccine Provides Postexposure Protection to Ebola Virus-Infected Nonhuman Primates.

Ebola virus (EBOV) causes lethal disease in up to 90% of EBOV-infected humans. Among vaccines, only the vesicular stomatitis virus platform has been successful in providing postexposure protection in nonhuman primates. Here, we show that an adjuvanted human adenovirus serotype 5 (Ad5)-vectored vaccine (Ad5-Zaire EBOV glycoprotein) protected 67% (6 of 9) and 25% (1 of 4) of cynomolgus macaques when administered 30 minutes and 24 hours following EBOV challenge, respectively.

Intranasal immunization with an adenovirus vaccine protects guinea pigs from Ebola virus transmission by infected animals.

Experimental Ebola virus (EBOV) vaccines have previously been shown to protect animals against a high dose intramuscular (IM) challenge, which is seen as a stringent challenge model. However, the protective efficacy against other modes of infection, such as contact with infectious hosts, is unknown. Using a previously established EBOV transmission animal model, we evaluated the efficacy of an adenovirus-based EBOV vaccine given to guinea pigs (gps) 4weeks before direct contact with untreated, infectious animals.

Ebola virus transmission in guinea pigs.

Unlabelled: Ebola virus (EBOV) transmission is currently poorly characterized and is thought to occur primarily by direct contact with infectious material; however transmission from swine to nonhuman primates via the respiratory tract has been documented. To establish an EBOV transmission model for performing studies with statistical significance, groups of six guinea pigs (gps) were challenged intranasally (i.n.

Airway delivery of an adenovirus-based Ebola virus vaccine bypasses existing immunity to homologous adenovirus in nonhuman primates.

Anti-adenovirus serotype 5 antibodies are capable of neutralizing adenovirus serotype 5-based vaccines. In mice and guinea pigs, intranasal delivery of adenovirus serotype 5-based vaccine bypasses induced adenovirus serotype 5 preexisting immunity, resulting in protection against species-adapted Ebola virus challenge. In this study, nonhuman primates were vaccinated with adenovirus serotype 5-based vaccine either intramuscularly or via the airway route (intranasally/intratracheally) in the presence or absence of adenovirus serotype 5 preexisting immunity.

Immune parameters correlate with protection against ebola virus infection in rodents and nonhuman primates.

Ebola virus causes severe hemorrhagic fever in susceptible hosts. Currently, no licensed vaccines or treatments are available; however, several experimental vaccines have been successful in protecting rodents and nonhuman primates (NHPs) from the lethal Zaire ebolavirus (ZEBOV) infection. The objective of this study was to evaluate immune responses correlating with survival in these animals after lethal challenge with ZEBOV.

Pentamers not found in the universal proteome can enhance antigen specific immune responses and adjuvant vaccines.

Certain short peptides do not occur in humans and are rare or non-existent in the universal proteome. Antigens that contain rare amino acid sequences are in general highly immunogenic and may activate different arms of the immune system. We first generated a list of rare, semi-common, and common 5-mer peptides using bioinformatics tools to analyze the UniProtKB database.

Evaluation of Different Strategies for Post-Exposure Treatment of Ebola Virus Infection in Rodents.

Zaire Ebola virus (ZEBOV) is a pathogen that causes severe hemorrhagic fever in humans and non-human primates. There are currently no licensed vaccines or approved treatments available against ZEBOV infections. The goal of this work was to evaluate different treatment strategies in conjunction with a replication deficient, recombinant human adenovirus serotype 5-based vaccine expressing the Zaire Ebola virus glycoprotein (Ad-CAGoptZGP) in Ebola infected mice and guinea pigs.

Impact of systemic or mucosal immunity to adenovirus on Ad-based Ebola virus vaccine efficacy in guinea pigs.

Background: Approximately 35% of the North American population and an estimated 90% of the sub-Saharan African population have antibodies against adenovirus serotype 5 (AdHu5) that are capable of neutralizing AdHu5-based vaccines. In mice, intranasal delivery of AdHu5 expressing the Zaire ebolavirus glycoprotein human adenovirus serotype 5 (Ad) containing the genes for the Zaire ebolavirus glycoprotein (ZGP) under the expressional control of a cytomegalovirus immediate early promoter (CMV)) can bypass systemic preexisting immunity, resulting in protection against mouse-adapted Zaire ebolavirus (Mayinga 1976).

Methods: Guinea pigs administered an adenovirus-based Ebola virus vaccine either intramuscularly or intranasally in the presence of systemically or mucosally induced adenovirus immunity were challenged with a lethal dose of guinea pig-adapted Zaire ebolavirus (Mayinga 1976) (GA-ZEBOV).

Replication, pathogenicity, shedding, and transmission of Zaire ebolavirus in pigs.

Unlabelled: (See the editorial commentary by Bausch, on pages 179-81.)

Background: Reston ebolavirus was recently detected in pigs in the Philippines. Specific antibodies were found in pig farmers, indicating exposure to the virus.

Recent advances in Ebolavirus vaccine development.

Ebolavirus is a highly infectious pathogen with a case fatality rate as high as 90%. Currently there is a lack of licensed Ebolavirus vaccines as well as pre- and post-exposure treatments. Recent increases in the frequency of natural human Ebolavirus infections and its potential use as a bioterrorism agent makes vaccine development a priority for many nations.

Enhanced protection against Ebola virus mediated by an improved adenovirus-based vaccine.

Background: The Ebola virus is transmitted by direct contact with bodily fluids of infected individuals, eliciting death rates as high as 90% among infected humans. Currently, replication defective adenovirus-based Ebola vaccine is being studied in a phase I clinical trial. Another Ebola vaccine, based on an attenuated vesicular stomatitis virus has shown efficacy in post-exposure treatment of nonhuman primates to Ebola infection.

RhaU of Rhizobium leguminosarum is a rhamnose mutarotase.

Of the nine genes comprising the L-rhamnose operon of Rhizobium leguminosarum, rhaU has not been assigned a function. The construction of a Delta rhaU strain revealed a growth phenotype that was slower than that of the wild-type strain, although the ultimate cell yields were equivalent. The transport of L-rhamnose into the cell and the rate of its phosphorylation were unaffected by the mutation.

L-Rhamnose transport is sugar kinase (RhaK) dependent in Rhizobium leguminosarum bv. trifolii.

Strains of Rhizobium leguminosarum which are unable to catabolize l-rhamnose, a methyl-pentose sugar, are compromised in the ability to compete for nodule occupancy versus wild-type strains. Previous characterization of the 11-kb region necessary for the utilization of rhamnose identified a locus carrying catabolic genes and genes encoding the components of an ABC transporter. Genetic evidence suggested that the putative kinase RhaK carried out the first step in the catabolism of rhamnose.

A genetic locus necessary for rhamnose uptake and catabolism in Rhizobium leguminosarum bv. trifolii.

Rhizobium leguminosarum bv. trifolii mutants unable to catabolize the methyl-pentose rhamnose are unable to compete effectively for nodule occupancy. In this work we show that the locus responsible for the transport and catabolism of rhamnose spans 10,959 bp.