Since the World Health Organization declared an international health emergency due to the Zika virus, at least a dozen companies have announced plans to develop a vaccine. Many are basing their research on prior work done on West Nile virus and dengue, which are related to Zika.
Dr. J. Joseph Kim, co-founder and CEO of Inovio Pharmaceuticals, thinks he can beat all of them. "Clinical product manufacturing will begin within the month," says Kim. "Our goal is to have a clinical supply of vaccines for human clinical testing by the end of the year." Inovio began work on a Zika vaccine in the fourth quarter of 2015, when it also began testing in animals. An Indian biotech company, Bharat Biotech, also says that it has a vaccine candidate.
About 80 percent of people who get Zika don't show any symptoms, which can include a fever and rash. But Zika in pregnant women has recently been linked to a serious birth defect called microcephaly, in which a baby is born with a small head and brain.
Kim co-founded VGX Pharmaceuticals about 15 years ago, after working in vaccine development for Merck. VGX later merged with Inovio. Kim says he co-founded his company precisely for opportunities like this--to be able to tackle a problem more quickly than could a giant pharmaceutical company.
The biotechnology Kim is using has the potential to work more quickly than traditional routes to vaccine development. Essentially, Inovio creates DNA sequences that look like pathogens, and uses them to alert the immune system. When the actual pathogens do show up, the immune system is then primed to fight them. "All of our products are just DNA sequences formulated in pure water," says Kim. "We're cutting through a lot of potential pitfalls of the safety or toxicity concerns of a traditional vaccine."
So far, Inovio has made the most progress with a so-called therapeutic vaccine--one that helps defeat a disease even after a patient has been diagnosed--for human papilloma virus, or HPV. The company chose HPV for its flagship efforts, says Kim, because about 25 percent of women who get cervical dysplasia as a result of HPV have immune systems strong enough to defeat the virus without outside help. So it was at least theoretically possible that the immune systems of other women could also learn to successfully fight the virus.
Inovio's vaccine against HPV is currently in Phase II clinical studies, and Kim says "about 50 percent" of the subjects in that trial are defeating the disease. "In Phase III, hopefully, we will get that higher," he says. He's optimistic that a Zika vaccine would come closer to providing blanket protection. He says that in animal trials, a vaccine against dengue protected "a hundred percent of animals from a pathogenic dengue challenge."
Kim seems unconcerned about the challenges of developing a vaccine for Zika. "We have a consistent record and successes across animals and early-to-mid human studies," he says. His worry is actually about human testing in the field, but, he says, he's already talking to WHO about how those studies would be done. Assuming, of course, Inovio gets there first.