A Phase 1, Open Label, Dose-Escalation Study to Evaluate the Safety, Reactogenicity and Immunogenicity of a Nanoparticle Carrier-Formulated Self-Amplifying RNA Vaccine Against Crimean-Congo Hemorrhagic Fever (HDT-321) in Healthy Adults
The goal of this clinical trial is to assess the safety, tolerability and immunogenicity of three dosage levels, and a single or two-dose administration regimen, of the investigational HDT-321 product administered intra-muscularly. The main questions it aims to answer are: * Is HDT-321 safe to use * Does HDT-321 provide protection against Crimean-Congo hemorrhagic fever virus (CCHFV) Researchers will record any adverse events and test blood samples to see if HDT-321 is safe and works to protect participants against Crimean-Congo hemorrhagic fever virus (CCHFV) Participants will: * Receive 1 or 2 doses of HDT-321 * Complete a memory aid and measurements for 7 days after receiving each dose of HDT-321 * Be followed throughout the study using phone calls and clinic visits to check for and record adverse events * Provide blood samples at specific study visits
• Males and non-pregnant females 18 to 64 years of age at the time of signing the ICF.
• Body mass index (BMI) 17 to 35 inclusive at screening.
• Considered by the PI or designee to be in good general health as determined by medical history, physical examination, vital sign measurements\*, and clinical laboratory assessments conducted no more than 30 days prior to the first study injection administration.
• Screening laboratory values within the laboratory reference ranges or considered non-clinically significant (NCS) if within Grade 1 severity on the toxicity grading scale.
• Negative human immunodeficiency virus (HIV) 1/2 antibody, hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) antibody.
• Women of childbearing potential must agree to use or have practiced true abstinence or use at least one acceptable primary form of contraception3 for at least 30 days prior to the first injection and for 60 days after the last injection. Female participants of childbearing potential must have a negative serum pregnancy test at screening and a negative urine pregnancy test on the day of and prior to each study injection.
• Able to understand and comply with planned study procedures and willing to be available for all study required procedures, visits, and telephone calls for the duration of the study.
• Provide written informed consent before initiation of any study procedures.
• Willing to abstain from donating whole blood or blood derivatives 30 days prior to screening and for the duration of the study.
⁃ Willing to refrain from receiving any licensed vaccine within 28 days prior to and after scheduled study injections.