Experimental Malaria Vaccine Offers Greater Protection in Humans

A new vaccine against malaria strains has shown protection for up to a year, which is better than the currently approved vaccine. The vaccine has been developed by a US-based company, Sanaria. The vaccine contains thousands of malarial parasites weakened with radiation. This PfSPZ vaccine was given to 55 volunteers in different dosages by dividing them into five separate groups.

Five of the 20 volunteers who received intravenous doses of 270,000 weakened parasites remained uninfected even after being bitten by mosquitoes with malaria three weeks after the final inoculation, at six months and again after a year.

Neither very high dosage worked nor small doses. The cumulative efficiency was 55%. This showed that the PfSPZ vaccine provided malaria protection for more than one year in 55 percent of people without prior malaria infection.

"It is now clear that administering the PfSPZ Vaccine intravenously confers long-term, sterile protection in a small number of participants, which has not been achieved with other current vaccine approaches,” said Robert A. Seder, chief of the Cellular Immunology Section of NIAID’s Vaccine Research Center and principal investigator of the trial.

“Based on the favorable safety profile, we’re testing higher doses in larger trials to see if even greater protection can be achieved long-term against other P. falciparum strains different than the vaccine strain,” he added.

Source-Medindia