Inovio Pharmaceuticals, Inc. announced that testing of its synthetic vaccine for the Zika virus induced robust antibody and T cell responses in non-human primates (monkeys), demonstrating the product’s potential to prevent infection from this harmful pathogen.
Inovio synthetically generated DNA vaccine constructs targeting multiple Zika virus antigens using its SynCon vaccine technology. These SynCon constructs were administered using Inovio's Cellectra electroporation delivery technology. Two doses of the Zika DNA vaccine delivered either intramuscularly or intradermally resulted in seroconversion, or the development of detectable specific antibodies in the blood, in all vaccinated non-human primates. Researchers also observed that vaccination generated robust and broad T cell responses as analyzed by the standardized T cell ELISPOT assay. These findings are vital given the potential importance of neutralizing antibodies in preventing infection and the role T cells play in clearing infection by killing cells that harbor the virus.
Dr. J. Joseph Kim, Inovio’s president & CEO, said, “With positive large animal results in hand we are moving aggressively to initiate and conduct our first Zika vaccine human trial in 2016.”
Dr. Kim will discuss Inovio’s Zika vaccine preclinical developments at an international forum hosted and organized by the Foundation for Vaccine Research and The National Academy of Medicine called “Ebola, SARS, MERS, Nipah, Zika Virus and Beyond: Challenges and Opportunities for Vaccine Development” in Washington DC. This high-level international forum is an invitation-only 1½ day event for decision-makers from the public and private sectors.
Inovio is developing its Zika vaccine, GLS-5700, with GeneOne Life Sciences (KSE:011000) and academic collaborators with whom Inovio has previously collaborated to advance its vaccines for Ebola and MERS into clinical development.
First identified in Uganda, Zika virus subsequently spread to equatorial Asia and over the past two years has rapidly spread through the South Pacific, including Hawaii, and to South America, Central America, and the Caribbean. Zika virus is a flavivirus, a family of viruses including yellow fever, dengue, and West Nile virus, which are introduced to people through mosquito bites. Because the Aedes species of mosquitoes that spread Zika virus is found throughout the world there is concern that outbreaks will spread to new countries. There is also concern that Zika can spread sexually, as has been reported for some returning travelers. In May, 2016, WHO stated that 58 countries and territories report continuing mosquito-borne transmission of Zika. Geographical distribution of the virus has steadily expanded.
The most common symptoms of Zika virus are fever, rash, joint pain, and conjunctivitis. More seriously, a possible link to a severe birth defect called microcephaly has recently been observed resulting from infected mothers. Microcephaly is a rare condition marked by an abnormally small head and incomplete brain development. There may also be a link with Guillain-Barré syndrome, a disease in which the body's immune system mistakenly attacks peripheral nerves. Symptoms start with muscle weakness. In severe cases the person is almost totally paralyzed and the disorder can be life threatening.
No vaccine or therapy currently exists for the Zika virus.