A DNA-based Zika vaccine from Inovio Pharmaceuticals Inc. (Plymouth Meeting PA) and South Korea’s GeneOne Life Science Inc. induced anti-Zika immune responses in an early stage human trial, US researchers reported last week.
Unlike conventional vaccines, which often use inactivated or killed versions of a virus, the Inovio-GeneOne shot is a synthetic vaccine made by reproducing sections of the Zika virus genome in a lab, and then loading them onto a ring of genetic material called a plasmid, Reuters reports. This vaccine is then injected beneath the skin and followed up with a device that generates electrical impulses, creating small pores in cells that allow the DNA to pass into cells.
After three doses of the Zika vaccine known as GLS-5700, all 40 healthy volunteers in the study developed Zika-specific antibodies.
“Everybody made antibodies,” said Dr. Pablo Tebas, an infectious disease expert at the University of Pennsylvania who led the study.
To see if these antibodies could be protective against the virus, blood from immunized study participants was injected into mice who were then exposed to Zika. Animals that had received the Zika-specific antibodies were protected.
“When we gave mice serum from the same people before they got the vaccine, they were not protected. The mice died,” Tebas said.
Tebas said the study shows how nimble synthetic DNA vaccines can be, noting that it took just seven months from the time the vaccine was first designed until the start of the clinical trial.
“This technique of making DNA vaccines is very fast,” Tebas said.
More testing will be needed to show the vaccine is effective at protecting people from Zika, and that could prove challenging given that the once explosive epidemic has slowed and there are few large populations now at risk for Zika infection.
Zika caused thousands of cases of the birth defect known as microcephaly in Brazil in 2015, prompting the World Health Organization to declare Zika a public health emergency in February 2016. Last November, the WHO dropped the emergency designation, but stressed that the virus, found in at least 60 countries, will keep spreading where mosquitoes that carry the virus are present.
Last month, Sanofi SA (Paris) ended development efforts on its Zika vaccine, based on an inactivated or killed Zika virus. Takeda Pharmaceutical Co. Ltd. (Tokyo) is still working on a Zika vaccine using this approach.
Yahoo. Great news on the medicine front. And it’s not in the category of a cure for something like, well, cancer.Steve's Take: @InovioPharma's #Zika breakthrough is great news, albeit early in the ballgame Click To Tweet
Most of us who follow the progress of new treatments for disease have been blown away this year with the steady drumbeat of breakthrough treatments for primarily cancer. Some are even being called “personalized medicine” and “cures” for a type of cancer that not that long ago was a certain death sentence. Terms like PARP inhibitors, CAR-T cell therapies, checkpoint inhibitors; names like Opdivo, Keytruda, Kymriah and Gleevec, just to name a few.
Now, an early stage clinical study of a Zika vaccine from Inovio Pharmaceuticals and GeneOne Life Science showed promise, inducing an immune response to the virus in all of the study participants. Not, nearly all. ALL.
I liked what Sy Mukherjee at Forbes had to say about this development. He believes it’s not exactly a cause for celebration quite yet:
“The trial only included 40 participants. But progress on fighting Zika, which can cause horrible birth defects in infected pregnant women, is always noteworthy–and the experimental treatment, GLS-5700, is a pretty unique vessel for combating the mosquito-borne virus that some researchers hope could surpass the more traditional approaches.”
The treatment differs from the typical vaccine because it’s synthetic. It doesn’t have a slain version of Zika virus, or one that’s been weakened to prompt the immune system to wage war. Rather, it’s lab-created using genomic Zika fragments, heaped onto a DNA fragment agreeable to humans, inserted into the body, and nudged into cell entrance and propagation by electrical shock.
Although not brand-spanking new to the vaccine realm, success with the DNA-based Zika serum sets bells, whistles and sirens off in my editorial brain. There are so many plusses and so few minuses relative to a candidate vaccine’s efficacy, it’s mind boggling. It either works or it doesn’t.
What’s still “out there” for me as a veteran observer is, safety. Is there something untoward in using an injection of synthetic DNA from a virus that staves off infection from a live virus but which alters something else in the human biology down the road with catastrophic ramifications?
As I wrote last week, we just learned from a study in the BMJ this past week that over half of new “breakthrough” cancer meds actually don’t work–four to five years down the road–in extending life span and/or quality of life. That was a wake-up call if there ever was one.
That doesn’t mean we punt on the Zika DNA vaccine by any means. Just don’t expect to see it in your Walgreen’s or Walmart’s pharmacy anytime soon.
Although the verdict is out how widespread the Zika virus ultimately will be, we know that wherever the infecting mosquitos breed, the virus will spread. And that’s a lot of the southern half of the US, despite the pervasive attitude of public complacency; despite sustained warnings we get from the CDC. (Obviously, sexual transmission of Zika doesn’t matter where one lives.)
“Synthetic DNA vaccines are an ideal approach for emerging infectious diseases like Zika,” said David B. Weiner, Ph.D., executive vice president of The Wistar Institute, director of Wistar’s Vaccine & Immunotherapy Center, developer of the Zika vaccine and collaborating author on the study.
“This new generation of DNA vaccines can be designed and manufactured rapidly,” Weiner continued. “They appear to be highly predictable for the generation of immunity in humans, have significant conceptual safety advantages, and they are more stable than most traditional vaccines, making them exceptionally practical to distribute during outbreaks, especially in regions where resources are limited and we need to be able to respond quickly to curb an emerging epidemic.”
Again, the results are still very early. But, if this sort of technique continues to succeed, there might be a way to speed up other critical vaccine development, and make a tidy profit in the stock market, too.
This Innovio name is out in front right now. I say it’s a Buy for the highly risk-tolerant portion of your portfolio.