The U.S. Department of Health and Human Services’ (HHS) Office of the Assistant Secretary for Preparedness and Response (ASPR) today announced a contract to develop an inactivated vaccine candidate to prevent the Zika virus infection and thereby the associated devastating birth defects. Inactivated vaccines have been shown to be safe and effective when given to special populations, including pregnant women and people with immunocompromised conditions.


Under a $43.18 million contract through June 2022 with Sanofi Pasteur of Swiftwater, Pennsylvania, ASPR’s Biomedical Advanced Research and Development Authority (BARDA) is providing funding and technical assistance to support the advanced development of a candidate Zika vaccine whose development was initiated at the Walter Reed Army Institute of Research (WRAIR). The advanced development to be conducted by Sanofi Pasteur will include further process development, scale up, production of clinical trial material, and two Phase I/II clinical trials that are targeted to begin in the first half of 2018.

“Developing safe and effective vaccines is a priority in our strategy to protect the public health against the Zika virus,” said Dr. Richard Hatchett, BARDA’s acting director. “This investment supports clinical trials and manufacturing of an additional Zika vaccine candidate that could help prevent Zika virus infection and the devastating birth defects that Zika virus can cause.”

Work on the vaccine candidate began this past March as a collaborative effort between WRAIR, BARDA and the National Institutes of Health’s (NIH) National Institute of Allergy and Infectious Diseases. WRAIR has signed a Cooperative Research and Development Agreement with Sanofi Pasteur to transfer aspects of the early stage process development and manufacturing to accelerate the development of this vaccine.

If Sanofi Pasteur’s work is successful at meeting data-driven milestones and additional funds are made available, the contract includes an option for up to an additional $130.45 million to fund Phase 3 clinical trials needed in order for the company to submit a license application to the FDA.

The vaccine is made from an inactivated (killed) whole Zika virus formulated with an adjuvant, a substance that enhances the vaccine’s ability to elicit an immune response. The selection of an inactivated vaccine is based on years of research that have led to several effective inactivated vaccines for related flaviviruses, including Japanese encephalitis and tick-borne encephalitis. Inactivated vaccines for various viral pathogens are often more stable than live, attenuated vaccines.

The most common symptoms of Zika are fever, rash, joint pain, and conjunctivitis. The illness usually is mild with symptoms lasting for several days to a week. People typically do not get sick enough to go to the hospital, and they rarely die of Zika. For this reason, many people might not realize they have been infected. However, Zika virus infection during pregnancy can cause certain birth defects including a severe birth defect called microcephaly.

With today’s award, BARDA has obligated $128.1 million out of its total of $132.4 million in repurposed funds for Zika. These funds are being used to develop Zika vaccines, diagnostics tests, blood screening tests, and pathogen reduction technologies through private sector partners. In addition, ASPR is providing Zika-positive blood samples to developers to validate the accuracy of new diagnostic tests.

As of September, HHS agencies across the department have obligated at least $433 million of repurposed funds to support Zika response and preparedness activities.