GlycoVaxyn Phase I Clinical Study Shows Positive Data with Shigella dysenteriae Vaccine Candidate
First important step towards the development of a multivalent Shigella vaccine against severe diarrheal disease
SCHLIEREN, Switzerland--(BUSINESS WIRE)--Oct 8, 2010 - GlycoVaxyn AG, a leader in the development of innovative vaccines, announced today that the Phase I study of its Shigella dysenteriae bioconjugate vaccine has been completed and met the primary and secondary endpoints: demonstration of safety and immunogenicity.
The study in forty healthy volunteers assessed the safety, tolerability and antibody response to the bioconjugate vaccine and was conducted at the Institute for Social and Preventive Medicine of the University of Zürich, Switzerland, under the supervision of principal investigators Professors Hatz and Steffen. The female and male subjects were randomly assigned to one of the four groups receiving ascending antigen dose with or without adjuvant. Two vaccinations were given at 60 days interval.
The candidate vaccine exhibited a good safety profile. No significant adverse reactions were observed at any of the vaccine dose levels.
In addition, the results showed that the majority of the volunteers achieved robust immune response. Eighty percent of the volunteers exhibited a minimum of a four-fold increase of their antibody levels compared to their own pre-vaccination level. All vaccine dose levels tested elicited significant IgG as well as IgA antibody responses.
“We are very pleased with these Phase I data,” said Philippe Dro, CEO of GlycoVaxyn. “This is the first time that a biologically synthesized conjugate vaccine has been tested in humans. Our vaccine shows a higher percentage of seroconversion compared to previous Shigella dysenteriae vaccines tested in clinical trials.” [1-3]
Shigellosis is a severe diarrheal condition resulting from bacterial infection. Each year, 1 million people are estimated to die from Shigella infection and 580,000 cases of shigellosis are reported among travellers from industrialized countries. 
“This is a first step towards the development of a multivalent Shigella vaccine where additional serotypes will be included to provide a broad coverage against this severe diarrheal disease. It opens up significant partnering opportunities for the company.” said Michel Greco, Chairman of GlycoVaxyn.
About Conjugate Vaccines
Conjugate vaccines are largely used to prevent important invasive bacterial diseases such as bacteraemia (bloodstream infection), pneumonia, and meningitis, with the market leader achieving nearly USD3 billion in annual sales in 2009. Conjugate vaccines are produced by linking a bacterial sugar antigen to a carrier protein. The current process used to develop and manufacture marketed conjugate vaccines is very complex, variable and expensive. GlycoVaxyn's novel technology allows the synthesis of complex immunogenic bioconjugates in a biological process in E. coli rendering both development and production significantly shorter and more controllable.
GlycoVaxyn is developing a portfolio of novel bio-conjugate vaccines against common severe bacterial infections produced with its unique, proprietary in-vivo glycosylation platform. With this platform, the company can develop and produce immunogenic glycoproteins in a simplified biological process that circumvents many of the challenges and uncertainties involved in currently used methods. In addition to the clinical stage Shigella vaccine, lead programs in preclinical stage are aimed at the prevention of hospital acquired Staphylococcus aureus infections, as well as pneumococcal invasive diseases and meningococcal group B meningitis. For further information, visit www.glycovaxyn.com.
1. Taylor, D.N., et al., Synthesis, characterization, and clinical evaluation of conjugate vaccines composed of the O-specific polysaccharides of Shigella dysenteriae type 1, Shigella flexneri type 2a, and Shigella sonnei (Plesiomonas shigelloides) bound to bacterial toxoids. Infect Immun, 1993. 61(9): p. 3678-87.
2. McKenzie, R., et al., Safety and immunogenicity of WRSd1, a live attenuated Shigella dysenteriae type 1 vaccine candidate. Vaccine, 2008. 26(26): p. 3291-6.
3. Launay, O., et al., Safety and immunogenicity of SC599, an oral live attenuated Shigella dysenteriae type-1 vaccine in healthy volunteers: results of a Phase 2, randomized, double-blind placebo-controlled trial. Vaccine, 2009. 27(8): p. 1184-91.
4. [cited; Available from: http://www.who.int/vaccine_research/diseases/shigella/en/.
Posted: October 2010