Development of a vaccine to prevent malaria in African children
Malaria continues to account for approximately half a million deaths each year. Children in highly endemic regions in Africa are the most severely affected. To date, an effective vaccine against malaria does not exist. In Tübingen, a vaccination approach which leads to full immunity against malaria parasites has now been tested in clinical trials on humans. The principle is based on the administration of attenuated pathogens that are recognisable to immune system but do not replicate uncontrollably and hence do not lead to a development of the illness. This promising approach is now being developed further at the Tübingen’s partner institute in Gabon where it is being adapted for use as a vaccination schedule in children. The aim is to protect humans in endemic regions where the disease occurs frequently and to offer travellers optimal malaria prophylaxis.
Although malaria accounts for approximately half a million deaths, usually of young children, it has not been possible to develop a vaccine up to now. A vaccine would much improve protection in the populations affected and could potentially lead to ending malaria in the long-term. Sub-Saharan Africa is particularly affected by malaria.
A series of DZIF trials conducted on healthy adults in Tübingen has shown that triple intravenous administration of attenuated Plasmodium falciparum (PfSPZ) malaria parasites leads to the development of immunity and protection against malaria. The malaria parasites are attenuated either by radiation (medical product name: PfSPZ vaccine) or by simultaneous administration of drugs (PfSPZ CVac). The vaccination schedules that have been developed up to now have proven to be safe and tolerated well in adult volunteers. However, no data on children are currently available. The BONNECHANCE trial investigates how immunisation with attenuated parasites can be simplified in order to develop a practicable vaccination schedule for use in the affected regions and as travel medication. The Institute for Tropical Medicine in Tübingen is consequently collaborating with the African Partner Institute Centre de Recherches Médicales de Lambaréné in Gabon. Vaccinations with the PfSPZ vaccine, PfSPZ CVac and placebo are being conducted on site in order to assess safety, tolerability and efficacy in school-age children. To this end, the vaccine’s side effects are documented and compared to a placebo cohort. In addition, we investigate whether the children acquire immune protection against malaria, for how long this protection lasts and if there are effects on pathogen transmission and how the immune response develops. All trial subjects are followed up for up to two years. As soon as the first findings confirming safety and efficacy in school children become available, the trial will be expanded to include and vaccinate pre-school children starting from the age of one year.
BONNECHANCE is a promising clinical trial that delivers important information on the safety, tolerability and efficacy of the PfSPZ vaccines. The aim of the trial is to deliver critical data for approval of PfSPZ vaccines.
