Inovio's first-in-human Zika, MERS vaccines pass early tests

Inovio’s Zika and MERS vaccine candidates, both the first to undergo human testing in those diseases, have turned in some positive early data.

A three-dose regimen of GLS-5700—a leading candidate in the Zika vaccine race—produced high levels of binding antibodies in all 39 subjects of a phase 1 trial, the company reports. The two-dose and single-dose versions also generated antibody response in 82% and 40% of subjects, respectively.

The vaccine was well tolerated, not arousing any significant safety concerns, according to Inovio. Researchers are currently evaluating its T-cell immune responses.

The notorious Zika emergency started in 2015 when the disease resurfaced in South America and quickly spread to about 50 countries, causing thousands of microcephaly cases along the way. In November, the World Health Organization removed the disease's "emergency" designation and shifted to a longer-term response.

Related: WHO: Fighting Zika still requires 'intense action,' but it's an emergency no longer

The Zika vaccine field is quite crowded, given the disease's worldwide attention. As Inovio conducts a second 160-participant trial of its shot, NIH is also testing its own candidate in phase 1. Other major players include Sanofi, GlaxoSmithKline and Takeda. Even though some 40 candidates are currently in development, the WHO said a safe vaccine for use in women of childbearing age is not likely before 2020.

Inovio’s co-founder David Weiner presented the data at the Coalition for Epidemic Preparedness Innovation’s first scientific meeting held in Paris. Launched last month, the initiative aims to raise $1 billion for a collaborative effort against potential infectious disease outbreaks.

Related: Pharma joins Gates Foundation, international governments in $1B outbreak prep group

Outside of Zika, the Plymouth Meeting, PA-based company also presented positive phase 1 numbers on its Middle East Respiratory Syndrome candidate, GLS-5300. In that study, a three-dose regimen induced high levels of binding antibodies in 92% of subjects.

MERS also caught the international community off guard when it first emerged in Saudi Arabia in 2012. Since then, the WHO has tracked about 2,000 cases and nearly 700 deaths around the globe.

But unlike the Zika market, Inovio’s candidate is still the only MERS vaccine being tested in humans. The company recently received funding and technical support from the International Vaccine Institute as part of a $34 million grant from the Samsung Foundation to support vaccine development against the disease.