Local researchers race to develop Zika vaccine

A small biotech company and a global vaccine maker in Southeastern Pennsylvania are among those racing to come up with a vaccine to combat the rise in the spread of the Zika virus in Brazil and other countries.

The United States has yet to face a major outbreak, but concern is growing, and the Centers for Disease Control and Prevention said Friday that the number of pregnant women in the U.S. infected with the Zika virus had tripled - from 48 to 157 - due to a change in the way the government counts cases.

Inovio Pharmaceuticals in Blue Bell is developing a DNA-based vaccine - using DNA sequences of the Zika virus - in a collaboration with the Wistar Institute in University City. Inovio has been working on the vaccine since late last year, and has tested it in mice and monkeys with positive results.

"I am very confident that we will be the first company with a Zika vaccine in the clinic," said Joseph Kim, Inovio CEO, who founded the company with immunologist and vaccine expert David Weiner, now at Wistar. Inovio expects to begin clinical tests in people in the next few months.

French-based Sanofi Pasteur, with U.S. headquarters in Swiftwater, in the Poconos, also is developing a Zika vaccine.

Sanofi currently has vaccines on the market for yellow fever, Japanese encephalitis, and dengue, which are in the same family, called flaviviruses, as Zika, and are spread by the same species of mosquito. Sanofi hopes its approach to the dengue vaccine can be leveraged to tackle Zika.

"We're moving as quickly as we can to get into clinical development," said Jon Heinrichs, who heads vaccine projects in predevelopment and early development for Sanofi in Swiftwater.

Sanofi will begin testing in animals in the next month or two, and hopes to begin Phase One tests in people by the end of the year.

The World Health Organization has reported that 14 companies globally are working on Zika vaccines, including Bharat, an Indian biotech; the U.S. National Institutes of Health; and Novavax, in Rockville, Md.

Several large pharmaceutical companies have said they are looking at whether their vaccine technologies could be used, including GlaxoSmithKline, Johnson & Johnson, Merck, and Pfizer.

Inovio said its DNA-based vaccine, which does not use traditional live or killed viruses, is quicker to develop, because it creates a synthetic DNA sequence in a lab that triggers the body to create the same antigens as from a killed or weakened virus, Kim said.

Inovio used the same DNA approach with an Ebola vaccine, which received $45 million from the U.S. Defense Advanced Research Projects Agency last year, and completed Phase One testing last year. The company is also working on a DNA-based vaccine for MERS, and is developing other cancer immunotherapies.

Inovio said the Zika testing in mice, which was done at Wistar, and in monkeys at a lab in Maryland generated "very robust" antibody and T-cell responses that showed the potential to prevent infection, Kim said.

The CDC said this month that 48 countries and territories have reported mosquito-borne transmission of Zika. The virus causes mild flulike symptoms in most infected people, but has been linked to an increase in babies born with microcephaly, which results in abnormally small heads and impaired brain development. Health authorities have also seen an increase in Guillain-Barre syndrome, a neurological disorder, in areas affected by Zika.

Sanofi's Zika vaccine studies in animals will be conducted in Cambridge, Mass., and Marcy-I'Etoile, France. The clinical testing in humans will be managed in Swiftwater, where the drugmaker has more than 70 buildings, 400 acres, and 2,500 employees.

Sanofi's technology uses the "backbone" of the long-established yellow fever virus to "express the surface proteins from other flaviviruses" - in the past for dengue and Japanese encephalitis, and now for Zika, Heinrichs said.

"We swap out the genes from yellow fever for those surface molecules of the virus and swap in the same genes from Zika in this case," he said.

Sanofi is looking to collaborate with smaller companies, academic institutions, and government agencies such as the NIH.

"Swiftwater is very involved right now. I am based in Swiftwater, as is much of the leadership team of R&D," Heinrichs said. "We are running the program at this time. Those individuals who will be running the clinical development are also based in Swiftwater. Everybody is working as quickly as they possibly can."

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