Testing of a malaria vaccine gets the green light

Researchers at Radboud university medical center and Leiden University Medical Center (LUMC) have been given the green light to deliberately infect volunteers with malaria in order to test a highly promising vaccine on them.

“‘That’s terrible. Who does that?’ That is often how people respond when I tell them about our research,” says Meta Roestenberg, researcher at the Department of Parasitology and Infectious Diseases at LUMC. “It gets stressful, but it may also be a huge step forward,” says Jona Walk, doctor and researcher at the Department of Medical Microbiology at Radboud university medical center. Together, Radboud university medical center and LUMC are going to test a promising malaria vaccine by utilizing controlled human infections, a method in which healthy, volunteer test subjects are deliberately infected with the disease in order to test the vaccine quickly and cheaply.

Green light

“We had already received a permit from the government, but last month, we also received permission from the Central Committee for Research Involving Human Subjects (Dutch: CCMO), so we were able to begin our research,” says Roestenberg. “We are still waiting on FDA approval from the US, where the vaccine is produced,” adds Walk. According to plan, the researchers will be able to begin recruiting healthy test subjects in the spring of 2017.

Weakened, live parasites as a vaccine

For years, the research groups at Radboud university medical center and LUMC have been working on this vaccine in which a weakened form of the malaria parasite is administered. During animal testing, researchers showed that the vaccine provided animals with safe, complete protection. “That is very promising, since the malaria vaccine which is currently available only provides limited, temporary protection. A vaccine that offers complete protection can prevent half a million deaths each year,” says Walk.

Getting bitten by mosquitoes

The testing of the vaccine consists of two phases. “During the safe phase, we make sure that the weakened parasites in the vaccine do not cause malaria in the test subjects,” explains Roestenberg. “We start with a low dosage and, if no problems occur, we inject the next test subject with a higher dosage.” If the results of the first phase are good, the second phase of the research will begin, during which it will be observed whether the vaccine provides the proper protection. The vaccinated subjects are infected with malaria by mosquitoes carrying the disease, which have been bred in the Nijmegen laboratory. The test subjects are closely monitored and receive complete and immediate curative medicine if malaria is detected.

Update

In the research that will take place this year, the vaccine will only be tested in the Netherlands. If the research results show that the vaccine works well, the two university medical centers will continue testing in Africa.