An experimental malaria vaccine has shown promising results in early-stage clinical trials, raising hopes of a new tool to battle the deadly disease.
The vaccine, which was developed by the US biotech company Sanaria, protected 12 out of 15 participants from malaria when delivered in high doses, researchers reported in the journal Science. “While we’re still in the early stages of testing, we believe this vaccine will be used to eliminate malaria,” said Stephen L. Hoffman, CEO of Sanaria. “It’s reasonable to suggest that within three to five years, a safe, reliable vaccine could be a commercial reality and provide medical benefit to a huge population.” Malaria, commonly spread by mosquitoes, infected 219 million people in 2010 and killed an estimated 660,000, according to the World Health Organisation. Ninety per cent of all malaria deaths occurred in the African region, mostly among children under five years of age. “The global burden of malaria is extraordinary and unacceptable,” said Dr Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health in Maryland where the clinical evaluation took place. “Scientists and healthcare providers have made significant gains in characterising, treating and preventing malaria; however, a vaccine has remained an elusive goal. We are encouraged by this important step forward.” The study looked at 57 healthy participants aged 18 to 45, none of whom had contracted malaria before. Of these, 40 received the vaccine, given by injecting live but weakened malaria-causing parasites into patients to trigger immunity. The remaining 17 were not vaccinated. All the participants were then exposed to malaria-carrying mosquitoes. Those not given the vaccine and those given low doses almost all became infected after exposure to malaria. Among the group given the highest dosage of the vaccine, only three of 15 participants became infected. “Scientists have struggled to produce an effective malaria vaccine for more than three decades,” Hoffman said. “These results show that we have a safe, successful, injectable vaccine that has the potential to save millions of lives.” There are a number of experimental malaria vaccines in clinical trials. The most advanced is GlaxoSmithKline’s RTS,S, which is currently being evaluated in a large Phase-3 clinical trial in Africa.