Researchers at Penn Medicine are leading efforts to develop a Zika virus vaccine. The phase 1 clinical trial is the first Zika vaccine study in humans.
Pablo Tebas, M.D.
Principal investigator Pablo Tebas, M.D., a professor of infectious diseases at the University of Pennsylvania’s Perelman School of Medicine, said approximately 40 participants have received the vaccine since July.
The vaccine injects DNA into the skin, where it is uptaken by cells that will produce a Zika virus protein. Researchers hope participants’ bodies will then develop antibodies against the protein, which will prevent Zika infection.
“We do not inject the virus itself, so there is no risk of participants becoming infected with Zika from the vaccine,” Dr. Tebas said. “Our goal with this phase 1 study is to make sure that the vaccine is safe.”
Participants at three sites – including the Perelman School of Medicine – received the DNA vaccine injection. The vaccine was administered using electroporation, where a small current of electricity briefly opens the cells, accelerating the uptake of DNA.
“The participants have tolerated the vaccine well,” Dr. Tebas said. “We expected that, because we have used this type of vaccine before. We knew it was going to be safe.”
Penn is conducting the study in partnership with Inovio/GeneOne Pharmaceuticals. Researchers will follow the participants for one year to determine how many antibodies participants develop after vaccination and how long the antibodies last.
Once a smaller study demonstrates the vaccine’s safety, larger studies will follow in the Caribbean and other areas with a higher risk of Zika infection to see if it has the ability to prevent infection, Dr. Tebas said.
“We want to see whether the vaccine is protective, and if so, how long that protection lasts,” he said. “That’s what we’re waiting for. We’re crossing our fingers to see if it will work.”