GLAXOSMITHKLINE SATELLITE SESSION
GSK's commitment: past, present and future
Dr Jan Poolman
8:30 DAY ONE
and Dr Lode Schuerman
Modern vaccine strategies have had a dramatic impact on the prevalence, morbidity and mortality of bacterial meningitis and respiratory infections. The introduction of Haemophilus influenzae type b (Hib) conjugated-polysaccharide vaccines has significantly reduced the prevalence of invasive Hib disease. Meningococcal vaccines have evolved from polysaccharide vaccines to the current conjugate multivalent vaccines with improved immunogenicity as well as a vaccine with efficacy against several serogroups. Combination vaccines, including conjugates, are now also available (such as DTPa/HB/IPV/Hib and Hib/MenC ) or in clinical trials with activity against one or more meningococcal serogroups as well as Hib (e.g. Hib-MenCY and ACWY). Pneumococcal vaccines have also progressed from polysaccharide formulations to vaccines conjugated to either CRM197 or protein D derived from Haemophilus influenzae (Hi).
Despite many advances, there are important limitations to the current technologies. Vaccines do not protect against all of the major bacterial species and serotypes implicated in meningitis and respiratory infections. For example, no vaccine is yet available against Men B; Hib vaccines do not protect against non-typeable Haemophilus influenzae (NTHi), Hia and other Hi types; and the current pneumococcal vaccines do not cover all serotypes causing disease. Therefore, further investments in research and development of new vaccines are required.
Download Dr Jan Poolman's presentation
Synflorix: a new pneumococcal conjugate vaccine
The heptavalent pneumococcal vaccine conjugated to CRM197 (PCV7) has demonstrated significant impact on invasive disease and pneumonia. The new PHiD-CV vaccine (Synflorix) launched earlier this year uses the NTHi protein D as the carrier protein for 8 of the 10 serotypes. In addition to the serotypes in PCV7, PHiD-CV covers serotypes 1, 5 and 7F which are associated with severe disease in young children.1 Clinical studies2 are underway to confirm and quantify the impact of the vaccine on NTHi diseases, such as otitis media, respiratory infections and meningitis, resulting from the Protein D carrier used in the vaccine.
Download Dr Lode Schuerman's presentation
Siber G, Klugman K, & Makela P, editors. Pneumococcal Vaccines. Washington (USA): American Society for Microbiology Press; 2008. p141.
2 http://www.clinicaltrials.gov (NCT00466947, NCT00861380 and NCT00839254)
WYETH SATELLITE SESSION
A debate between Professor Adam Finn (for) and Professor Andrew Pollard (against).
13:30 DAY ONE
Chair: Professor David Goldblatt, Institute of Child Health, University College London
‘Polysaccharide-conjugate vaccines offer at best a partial and temporary solution to the problem of pneumococcal disease and available resources should be diverted from deployment of such vaccines and invested instead in development and implementation of protein antigen vaccines without delay.'
The 7-valent pneumococcal conjugate vaccine (PCV7) is in wide use around the world and has been highly effective at reducing the burden of pneumococcal disease in vaccinated children. Reductions in vaccine-type disease in unvaccinated children and adults (“herd” effects) and significant declines in antibiotic-resistant infections have also been reported. Increases in disease due to non-vaccine serotypes (replacement) warrants ongoing vigilance but has not, as yet, significantly impacted the overall observed benefits of the vaccine. Higher valency vaccines have the potential to prevent an additional proportion of disease globally, however, it seems highly unlikely that it will be feasible to develop a conjugate vaccine including all 91 pneumococcal serotypes. As a result efforts are also focused on developing alternative vaccine strategies, especially the development of vaccines based on conserved pneumococcal proteins. These “common proteins” could protect against many types of pneumococcus but a leading candidate hasn’t yet emerged from the pack, and the availability of such a vaccine still appears to be some years off.
Has the time come to divert resources from conjugate vaccine development to hasten the availability of protein-based vaccines?
Join us for this debate to have your say!
NOVARTIS SATELLITE SESSION
New Approaches to Meningococcal Prevention
8:20 DAY TWO
Chair: Dr Chris Worth, UK Medical Director, Novartis Vaccines
Future control of Group C meningococcal disease in the UK
Professor Andrew Pollard, University of Oxford, UK
Meningococcal disease remains one of the leading infectious causes of death in the UK with most cases now caused by serogroup B meningococci but during the 1990s a substantial proportion of cases were caused by group C bacteria. The introduction of the group C meningococcal vaccine (MenC) in 1999 for all children and young people under the age of 19 years led to a dramatic and sustained reduction in disease caused by serogroup C Neisseria meningitidis in the UK. Whilst most age groups received a single dose, the infant programme was initially introduced as a 3 dose priming course with no booster. It was found that antibody persisted poorly after infant immunization and, in 2006, the programme was switched to a 2 dose priming course (at 3 and 4 months of age) with a booster at 12 months of age. The success of this vaccine programme in producing population protection in the UK depends on a combination of herd immunity, direct protection through bactericidal antibody and immunological memory. 10 years on, MenC disease is at an all time low, almost certainly because of the massive reduction in transmission following the catch up campaign in 1999, but population levels of antibody and herd immunity are now waning amongst children, and strategies to prevent a future resurgence of disease should be considered. Since transmission is thought to be driven by adolescents and young adults (including parents), potentially including a teenage booster of MenC or MenACWY vaccine in the UK schedule could secure future disease control.
Broadening meningococcal protection
Dr Rino Rappuoli, Novartis Vaccines, Siena, Italy
The introduction of polysaccharide-protein conjugate vaccines has allowed well-demonstrated improvements in immunogenicity over polysaccharide vaccines to occur. A MenACWY vaccine with diphtheria carrier protein (MenACWY-D) was licensed in North America in 2005. An investigational quadrivalent meningococcal ACWY (Men ACWY-CRM) conjugate vaccine is in the last stages of development using the well-established Corynebacterium diphtheriae cross reactive material (CRM 197). A large clinical database for this latter investigational vaccine now exists with 24 clinical trials completed or ongoing with over 14,000 subjects having received the final formulation of the vaccine. Through its development, the vaccine has been shown to be immunogenic and well tolerated through all age groups including infants ((≥2 months of age). Favourable immunogenicity compared to MenACWY-D was demonstrated in adolescents and adults, with favourable immunogenicity compared to MPSV4 being demonstrated in children, adolescents and adults. The persistence of antibodies has also been shown after vaccination using human and rabbit complement as protective markers. Concomitant administration with other routine vaccines such as combined tetanus, reduced diphtheria, acellular pertussis (Tdap), and HPV did not adversely affect immune response or tolerability. The introduction of a new Men ACWY-CRM conjugated vaccine has the potential for allowing increased flexibility into the current UK vaccination schedule