|Articles|March 24, 2023

HIV and Zika Vaccination Produces Robust Immune Response in Mothers and Newborns

Author(s)Nina Cosdon

Using a pregnant rabbit model, investigators found a robust antigen-specific antibody response in pregnant rabbits against HIV and Zika virus.

HDT Bio Corp. announced today that their self-amplifying replicon mRNA (repRNA) vaccine produced a robust maternal and neonatal immune response against the HIV and Zika viruses.

The study, published in the journal Molecular Therapy, evaluated the repRNA/LION vaccine and its induction of in utero transfer of maternal antibodies in a pregnant rabbit model.The research was funded by the National Institute of Allergy and Infectious Diseases (NIAID) and led by investigators at HDT Bio, in collaboration with Duke University and the Seattle Children’s Research Institute.

The HIV and Zika viruses were selected for the repRNS/LION platform due to their ability to cause potentially fatal infection in newborns via mother-to-child (vertical) transmission. Using a pregnant rabbit model, the investigators found a robust antigen-specific antibody response in pregnant rabbits. The association between maternal and newborn serum antibody levels indicated a significant level of transfer.

“Our results support further development of the LION/repRNA vaccine platform for maternal and neonatal settings,” the study authors wrote. Notably, immunizing the neonatal rabbits also induced a robust immune response, regardless of whether the maternal rabbits were vaccinated.

“These data demonstrate that the vaccines derived from our repRNA/LION platform technology have the potential to offer protection not only to the vaccinated individual but also to their offspring,” said Steven Reed, PhD, CEO of HDT Bio. “Moreover, our platform has several advantages, including cost-effectiveness, safety, and stability at refrigeration temperatures. This reduces barriers for distribution of our vaccines to developing nations where these diseases are endemic, making them accessible to those who need them most.”

HDT Bio’s repRNA/LION is the first self-amplifying RNA vaccine platform to ever receive a regulatory authorization. HDT Bio is a developer of immunotherapies for oncology and infectious diseases, based in Seattle, Washington. The clinical-stage biopharmaceutical company focuses on products that harness host-directed immune responses.


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