Investigational malaria vaccine found to be safe and protective

2013

Challenge

Roughly 600,000 people die of malaria each year , most of them infants and children . Malaria transmits to humans through the bite of an infected mosquito, after which infectious malaria parasites travel to the liver, where they multiply and then spread throughout the body. Scientists and healthcare workers have made significant gains in characterizing, treating, and preventing malaria, but a vaccine has remained an elusive goal.

Advance

In a Phase I clinical trial, IRP investigators from the NIAID Vaccine Research Center, in collaboration with Sanaria Inc., the Walter Reed Army Institute of Research, and the Navy Medical Research Center, evaluated the safety and efficacy of a novel investigational malaria vaccine called PfSPZ. This vaccine includes live, but weakened, malaria parasites, called sporozoites, of the species Plasmodium falciparum—the most deadly of the malaria-causing parasites.

Impact

The study showed that a dose-dependent level of protection against malaria can be achieved when the PfSPZ vaccine is administered intravenously. While the results are promising, additional work is required to evaluate the vaccine in more people and to optimize the dose, schedule, and delivery to determine whether it confers long-lasting protection.

Publications

Seder RA, Chang LJ, Enama ME, Zephir KL, Sarwar UN, Gordon IJ, Holman LA, James ER, Billingsley PF, Gunasekera A, Richman A, Chakravarty S, Manoj A, Velmurugan S, Li M, Ruben AJ, Li T, Eappen AG, Stafford RE, Plummer SH, Hendel CS, Novik L, Costner PJ, Mendoza FH, Saunders JG, Nason MC, Richardson JH, Murphy J, Davidson SA, Richie TL, Sedegah M, Sutamihardja A, Fahle GA, Lyke KE, Laurens MB, Roederer M, Tewari K, Epstein JE, Sim BK, Ledgerwood JE, Graham BS, Hoffman SL; VRC 312 Study Team. (2013). Protection against malaria by intravenous immunization with a nonreplicating sporozoite vaccine. Science. 341(6152), 1359-65.