Vaccine Info

mRNA-1893 Zika Vaccine

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Last reviewed
August 3, 2022

mRNA-1893 Zika Vaccine Description 2022

Moderna's mRNA-1893 vaccine candidate contains an mRNA sequence encoding for the structural proteins of the Zika virus. It is designed to cause cells to secrete virus-like particles, mimicking the cell's response after a natural infection. Preclinical data published in the Journal of Infectious Diseases have shown that vaccination with mRNA-1893 protected against Zika virus transmission during pregnancy in mice.

On August 19, 2019, Moderna, Inc. announced that the U.S. Food and Drug Administration (FDA) had granted Fast Track Designation for its investigational mRNA-1893, currently being evaluated in a Phase 1 study to prevent Zika virus infection in healthy adults. This project has been funded in whole or in part with Federal funds from the Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority (BARDA), under Contract No. HHSO100201600029C.

As of July 12, 2022, the phase 1 study (mRNA-1893-P201) is active in Puerto Rico, with a completion date scheduled for April 26, 2024. On August 3, 2022, Moderna confirmed mRNA-1893 Phase 2 study was ongoing.

Headquartered in Cambridge, Mass., Moderna (Nasdaq: MRNA) currently has strategic alliances for development programs.

mRNA Technology

Recognizing the broad potential of mRNA science, Moderna set out to create an mRNA technology platform that functions very much like an operating system on a computer. It is designed so that it can plug and play interchangeably with different programs. Generally, the only thing that changes from one potential mRNA medicine to another is the coding region – the actual genetic code that instructs ribosomes to make protein. Utilizing these instruction sets gives the investigational mRNA medicines a software-like quality. Moderna also can combine different mRNA sequences encoding for various proteins in a single mRNA investigational medicine.

mRNA-1893 Indication

mRNA-1893 is indicated for avoiding transmission of the Zika disease from a mother to an unborn child.

mRNA-1893 Dosage

Interim Phase 1 Data - All four cohorts (10 µg, 30 µg, 100 µg, 250 µg) of the Phase 1 study of mRNA-1893 have been dosed. An interim study analysis reports safety and immunogenicity data from the ten µg and 30 µg cohorts. In addition, neutralizing antibody titers were assessed using Plaque Reduction Neutralization Test (PRNT50) and microneutralization assays (M.N.), which provide equivalent guidance for interpreting the neutralizing immune response.

mRNA-1893 News 2019 - 2022

May 4, 2022 - Moderna confirmed the Phase 2 study of mRNA-1893 is ongoing in the U.S. and Puerto Rico and is being developed in collaboration with BARDA.

November 10, 2021 - The Hindustan Times reported that ZIKA virus cases had reached over 100 cases. Of the 105 positive cases, 17 are now negative.

November 4, 2021 - Moderna announced that its phase 2 study of mRNA-1893 is ongoing in the U.S. and Puerto Rico. mRNA-1893 is being developed in collaboration with BARDA. 

April 14, 2020 - First interim analysis of the Phase 1 study shows that ten µg and 30 µg dose levels seroconverted 94% and 100% of seronegative participants, respectively, and effectively boosted seropositive participants; both dose levels were generally well-tolerated.

August 19, 2019 - Moderna Inc. announced that the Food and Drug Administration had approved its potential vaccine for the Zika virus for a fast track to approval. Fast Track is designed to facilitate the development and expedite the review of therapies and vaccines for serious conditions and fill an unmet medical need. Programs with Fast Track designation may benefit from early and frequent communication with the FDA, in addition to a rolling submission of the marketing application. 

mRNA-1893 Clinical Trials

mRNA-1893 Zika vaccine is currently being studied in two clinical trials.

Following a two-dose vaccination schedule of mRNA-1893 given 28 days apart in phase 1, the ten µg and 30 µg dose levels were both generally well-tolerated, and there were no vaccine-related serious adverse events or adverse events of particular interest. The most frequent solicited adverse reaction was local pain at the injection site. The safety profile did not appear affected by the second vaccination nor flavivirus-positive baseline serostatus. The analysis also showed that the ten µg and 30 µg dose levels induced a neutralizing antibody response in both flavivirus infection-naïve (seronegative) participants and participants with pre-existing flavivirus antibodies (seropositive), as shown by geometric mean titers and seroconversion rates. Notably, a single vaccination of the 30 µg dose level was sufficient to convert baseline flavivirus seronegative participants.

Clinical Trials

No clinical trials found