Inovio’s Zika virus vaccine candidate has demonstrated “robust and durable immune responses” in mice, raising hopes for a way to tackle the rapid spread of the disease.

The DNA vaccine resulted in the development of detectable specific antibodies in the blood in all vaccinated mice. The company says it is now looking to test it in non-human primates and hopes to initiate Phase I human testing before the end of 2016.

Inovio is developing its Zika vaccine with GeneOne Life Sciences and academic collaborators. It builds on the company’s previous work in dengue and West Nile virus vaccines, diseases which are in the same family as Zika.

The rapid spread of the Zika virus across South and Central America, as wall as its apparent association with an increase in the number of babies being born with small heads, or microcephaly, led the World Health Organisation to declare it a public health emergency of international concern on February 1st. 

The WHO has since called for $56 million to help fast-track vaccines, carry out diagnostics, and research the disease.

Sanofi, which also has experience with dengue vaccines, announced that they would be launching a project to find a Zika vaccine earlier this month. Meanwhile, GSK has said it is investigating whether its own vaccine technology is suitable.