HDT Bio Publishes Peer-Reviewed Preclinical Study Demonstrating Robust Immunological Response in Mothers and Newborns Following repRNA/LION™ Vaccination

• LION-formulated, repRNA vaccination against HIV-1 and ZIKV successfully produced a robust immunological response in pregnant rabbits; maternal antibodies were transferred in utero to newborn kits
• Findings published in the peer-reviewed journal Molecular Therapy

SEATTLE, March 24, 2023 /PRNewswire/ -- HDT Bio Corp., a developer of immunotherapies for oncology and infectious diseases, today announced the peer-reviewed publication of preclinical data demonstrating that its self-amplifying replicon mRNA (repRNA) vaccines, delivered via HDT Bio's proprietary LION nanoparticle formulation, provide robust maternal and neonatal immunogenicity against two pathogens with high mother-to-child transmission risk: HIV-1 and Zika virus (ZIKV). The data were published in the journal Molecular Therapy, in the article entitled "Evaluation of repRNA vaccine for induction and in utero transfer of maternal antibodies in a pregnant rabbit model."

"The transmission of certain viruses from mother to developing fetus poses a significant risk to newborns," said Steven Reed, Ph.D., Chief Executive Officer of HDT Bio. "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. 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."

The study, funded by NIAID and led by researchers at HDT Bio in collaboration with Duke University and the Seattle Children's Research Institute, investigated the potential for HDT Bio's repRNA/LION platform technology to elicit an immune response against infectious diseases transmitted from mother to child. Two viruses, HIV-1 and ZIKV, were chosen for the study due to their significant role in causing infections in newborns following mother-to-child transmission. Using a pregnant rabbit model, researchers demonstrated robust induction of antigen-specific antibody responses in pregnant rabbits and a significant correlation between maternal and newborn serum antibody levels indicative of transferal. Furthermore, immunization in rabbit kits also led to a robust immunogenic response, regardless of the maternal vaccination status.

The publication can be found on the Molecular Therapy website and on the Publications page of the HDT Bio website.

About HDT Bio

HDT Bio is a Seattle-based, clinical-stage biopharmaceutical development company. With core technology and expertise in nucleic acid formulation, the company develops products that seek to harness host-directed immune responses. HDT Bio's work focuses on infectious disease and oncology vaccines and therapeutics through early-stage collaborations with partners worldwide. The company's vaccine platforms combine formulation and adjuvant ingredients to stabilize and deliver RNA to the immune system to stimulate responses. HDT Bio's repRNA/LION^™ is the first self-amplifying RNA vaccine platform to ever receive a regulatory authorization.

Learn more at https://www.hdt.bio

SOURCE HDT Bio Corp.