The US Centres for Disease Control and Prevention has granted clinical trial approval for an experimental Zika vaccine. The drug, which will be tested on a small sampling of human participants, arrives a mere five months after the World Health Organisation declared Zika a public health emergency. Image: pahowho/Flickr, CC BY-ND 2.0
The vaccine, named GLS-5700, is a collaborative effort between Inovio Pharmaceuticals of Pennsylvania and GeneOne Life Science of South Korea. Yesterday, the companies announced a phase I study with 40 healthy subjects to evaluate the safety, tolerability and efficacy of the drug.
"We are proud to have attained the approval to initiate the first Zika vaccine study in human volunteers," noted Inovio CEO J. Joseph Kim in a statement. "As of May 2016, 58 countries and territories reported continuing mosquito-borne transmission of the Zika virus; the incidences of viral infection and medical conditions caused by the virus are expanding, not contracting."
The company plans to start clinical trials in a few weeks and expects to report the results later this year. Should things go well, the vaccine will be promoted to phase II clinical trials. It certainly appears that things are moving quickly — and they most certainly are as far as these things go — but it could still take years before GLS-5700 can be used in the field.
During preclinical testing, this vaccine proved its worth in animal models, "demonstrating the product's potential to prevent infection from this harmful pathogen in humans".
It's pretty remarkable that clinical testing for a disease that only attained emergency status a few months ago has already been slated for clinical testing. Up until recently, scientists knew very little about this obscure virus that was deemed largely harmless. But as we now know, Zika can cause severe birth defects, including microcephaly. Clearly, the urgency of the situation has prompted the pharmaceutical industry to push things forward.
It also helps that Zika, as a mosquito-spread flavivirus, is similar to Dengue and West Nile — disease for which vaccines are already under development. Scientists did not have to start this experimental new Zika vaccine from scratch.