Chasing the Dream: The World’s Most Powerful Malaria Vaccine

“You have to give Steve Hoffman credit” for picking up the idea again, says Sherman, the retired professor from the University of California, Riverside. “The bitter irony is that after all of these years, … we’ve come full circle with Sanaria. I call this ‘back to the future.’”

While Hoffman says that Vanderberg “played a major role at the outset of the entire process in the late ’60s and early ’70s,” he never talked to the senescent researcher, 14 years his senior, before establishing Sanaria. “I would have told him he was wasting his time,” Vanderberg says, at the time still thinking that the vaccine was never going to fly. But over the years, Vanderberg has gone from dubiety to hopefulness, and he now eagerly follows Hoffman’s progress.

Video: Inside the lab, NYU researchers hunt for an effective malaria vaccine.

In 2007, Sanaria left the strip mall and moved into a larger biotech facility, but the company still operates like something out of a 1960s sci-fi flick. In a high-security environment, workers raise mosquitoes and feed them human donor blood infected with malaria. The parasites then grow and invade the insects’ salivary glands. After irradiating the mosquitoes, workers armed with a microscope and some sophisticated cutlery patiently dissect the glands to harvest the parasites. The weakened, live sporozoites are then purified and frozen until they can be injected into humans with a normal syringe.

“Everybody said you can’t make it,” Hoffman says tersely. “Then they said you can’t make it pure; then they said you can’t make it sterile; then they said you can’t bottle it. We have systematically overcome all of those problems.”

Sanaria’s success has drawn attention, and money, from many people in the field. “Over the past two years, I’ve seen tremendous progress in the manufacturing process,” says Dr. Christian Loucq, director of The PATH Malaria Vaccine Initiative, a global organization that supports the development of malaria vaccines and has administered a $29-million grant to Sanaria from the Bill and Melinda Gates Foundation. While scaling up production is always a hurdle, Loucq continues, “Sanaria has achieved so much, they’re the kind of people who could eventually make it.”

But not everyone is that optimistic. Dr. Robert Ménard, a malaria expert at the Pasteur Institute in Paris, points out that Hoffman has been overeager before and failed with a crash. In the mid-1980s, for instance, Hoffman allowed infected mosquitoes to bite him after injecting himself with a molecular vaccine he had developed. A few days later, he developed a full-blown malaria attack while giving a speech at a conference.

“He’s very, very upbeat, as Steve Hoffman has always been for all the previous approaches,” Ménard says. He remains skeptical about the sporozoite vaccine, but says lack of data for the revamped vaccine makes it hard to assess. In contrast to the most advanced molecular vaccine, developed from a sporozoite protein by GlaxoSmithKline and about to be tested in 16,000 African children, Sanaria’s vaccine has yet to go through a single clinical trial. It is unclear how long protection will last, how many injections are needed and how they should be given, since the weakened sporozoites still cannot be injected directly into the blood. The answers to these questions will be vital to the vaccine’s success in the field.

Earlier this year, however, the U.S. Food and Drug Administration determined that Sanaria’s product was safe enough to be tried on humans, and about 100 volunteers received a first dose of the vaccine in May. If it works anything like its mosquito-based predecessor, it will do what no other malaria vaccine has ever done: It will make sure that not a single parasite survives in the body of an immunized person. “Ours is the gold standard,” Hoffman says. “All we have to do is figure out how to best administer it now.”

For that, he turns to Vanderberg, the sole survivor of the original research group at the prison. After almost a half-century of studying the intricate mechanics of parasite invasions and how to thwart them, Vanderberg can help Hoffman determine where and how the vaccine should be injected to make it maximally protective. In return, Hoffman could be the one to make the aging professor’s 40-year-old dream come true.

Perhaps one day millions of African children will owe their lives to a hardened bunch of malaria-ridden inmates from the Maryland House of Correction.

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