BACKGROUND & STRATEGY
Malaria infection during pregnancy constitutes a major health problem that can lead to the development of placental malaria (PM), affecting particularly vulnerable demographic groups, pregnant women and babies in Africa.
In 2020, approximately 11 million pregnant women (34%) were exposed to malaria infection, accounting for an estimated 200,000 infant deaths annually and 819,000 children with low birthweight.
Placental malaria causes adverse pregnancy outcomes, including anaemia and high blood pressure in first-time pregnant women, and low birth weight, which are associated with a higher risk of foetal and neonate illness and mortality.
WHO promotes three strategies for the control of PM in Africa, which include provision of intermittent preventive treatment for malaria in pregnancy (IPTp) with sulfadoxine-pyrimethamine (IPT-SP), use of insecticide-treated nets (ITNs), and prompt diagnosis and treatment of confirmed infections.
Even if effective in reducing the malaria burden in pregnant women living in endemic areas, the global implementation of such approaches is threatened by the emergence of widespread resistance of both mosquitoes to insecticides and of parasites to anti-malarial drugs. The development of an effective vaccine would therefore be an excellent tool to reduce the incidence and severity of placental malaria and protect the mother and unborn child during pregnancy.
The two VAR2CSA-based PM vaccine candidates PRIMVAC and PAMVAC, developed by Inserm, FR, and University of Copenhagen, DK respectively, have been previously tested in two independent phase Ia/Ib clinical trials in Europe and Africa,.
The results demonstrated that both vaccines are safe, well-tolerated and induce good homologous immune responses.
Building on these successes, ADVANCE-VAC4PM will further advance the clinical development of these two PM vaccine candidates with the ultimate goal to improve and broaden the vaccine-induced immune response, in preparation of future phase 2/3 clinical trials. This will be achieved by:
Using a novel vaccine platform based on capside-Virus-Like Particles (cVLPs)
Evaluating co-administration of PRIMVAC and PAMVAC-cVLP
The activities funded by ADVANCE-VAC4PM will complement efforts currently undertaken by the consortium partners in the VAC4PM project funded by the Japanese Global Health Innovation Technology (GHIT) Fund.
The clinical trial activities will be embedded in capacity building efforts including workshops, training of MSc/PhD students, a mentorship program for African early career researchers and strengthening of clinical and immunology laboratory capacity. Digital tools will be developed for monitoring pregnancy outcomes in preparation of future efficacy trials. Modelling the cost-effectiveness, feasibility and acceptability of placental malaria vaccines will also be conducted.