A Phase I Study to Evaluate the Safety, Tolerability, and Immunogenicity of an mRNA Vaccine Against Herpes Simplex Virus Type 2 (HSV-2) Post-Vaccination

A Phase I, Dose-escalation Study to Evaluate the Safety, Tolerability, and Immunogenicity of an mRNA Vaccine Against Herpes Simplex Virus Type 2 (HSV-2) in Healthy Participants Aged 18-55 Years, Stratified by Serostatus

A Preliminary Evaluation of the Safety and Immunogenicity Post-Vaccination with Different Doses of an mRNA Vaccine against Herpes Simplex Virus Type 2 (HSV-2) in Populations with Different Serostatus

Study Overview

• Status: Enrolling by invitation
• Conditions: Genital Herpes
• Intervention / Treatment: Biological: Placebo Group; Biological: Low-Dose Cohort; Biological: Mid-Dose Cohort; Biological: High-Dose Cohort

• Study Type: Interventional
• Enrollment (Estimated): 144
• Phase: Phase 1

Contacts and Locations

Study Locations

• China
  • Beijing, China
    • Beijing Jishuitan Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Is a healthy male or female aged 18 to 55 years (inclusive) at the time of screening.
• Has provided written informed consent prior to performing any study-specific procedure.
• Is available and willing to comply with all study procedures for the entire duration of the study.
• For participants of childbearing potential: agrees to practice highly effective contraception for the required period and has no plans for reproduction or gamete donation.
• Provides consent for HSV-1/HSV-2 serology testing at screening.

Exclusion Criteria:

• Axillary temperature >37.0°C during screening and/or on the day of vaccination.
• History of clinically diagnosed genital herpes within 6 months prior to the first vaccination.
• Acute infectious disease or acute exacerbation of a chronic condition within 3 days prior to screening/vaccination.
• Positive blood pregnancy test at screening or currently breastfeeding (for female participants).
• History of severe allergic reactions requiring medical intervention (e.g., anaphylaxis, angioedema, Arthus reaction, allergic purpura), severe adverse reactions to previous vaccinations, or known hypersensitivity to any component of the investigational vaccine (e.g., lipid nanoparticles).
• Known or suspected malignancy, autoimmune disease, immunodeficiency, organ transplantation, or immunosuppression (e.g., HIV infection, systemic lupus erythematosus [SLE], rheumatoid arthritis).
• Use of immunosuppressants or immunomodulators (e.g., systemic corticosteroids for >14 consecutive days) or cytotoxic therapy within 6 months prior to the first vaccination, or planned use during the study.
• Congenital anomalies or developmental disorders affecting organ function.
• History of cardiovascular diseases (e.g., myocardial ischemia, myocardial infarction, myocarditis, pericarditis, idiopathic cardiomyopathy, arrhythmias), or any condition increasing the risk of myocarditis/pericarditis; QTcF >450 ms for males or >470 ms for females; or uncontrolled hypertension (systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg despite medication).
• For HSV-1/HSV-2 seronegative participants: clinically significant abnormalities in hematology, blood biochemistry, coagulation, or urinalysis parameters at screening.
• For HSV-1/HSV-2 seropositive participants: hematology, blood biochemistry, coagulation, or urinalysis parameters ≥ Grade 1 per the study-specific toxicity grading scale and deemed clinically significant by the investigator.
• Contraindications to intramuscular injection (e.g., thrombocytopenia, coagulation disorders).
• Medical conditions requiring intervention affecting the endocrine, hematologic, hepatic, renal, respiratory, metabolic, or skeletal systems.
• History of convulsions (excluding febrile seizures in childhood), epilepsy, encephalopathy, psychiatric disorders, or other neurological conditions; or family history of psychiatric disorders.
• Positive markers for HBV, HCV, HIV, or syphilis infection.
• Administration of blood products or immunoglobulins within 3 months prior to the first vaccination or planned use during the study.
• Treatment with anti-herpetic drugs (e.g., acyclovir, valacyclovir, famciclovir, ganciclovir) for genital herpes within 6 months prior to the first vaccination.
• Receipt of live-attenuated vaccines within 14 days, or subunit/inactivated vaccines within 7 days prior to vaccination.
• Participation in another clinical trial (drug, device, or vaccine) within 3 months prior to the first vaccination or concurrent enrollment in any interventional study.
• Any other condition deemed by the investigator to compromise participant safety or interfere with study objectives.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo	Biological: Placebo Group; Each human dose: 0.25 mL, 0.5 mL, or 1.0 mL
Experimental: Low-Dose; HSV-2 mRNA Vaccine	Biological: Low-Dose Cohort; Each human dose is 0.25 mL
Experimental: Mid-Dose; HSV-2 mRNA Vaccine	Biological: Mid-Dose Cohort; Each human dose is 0.5 mL
Experimental: High-Dose; HSV-2 mRNA Vaccine	Biological: High-Dose Cohort; Each human dose is 1.0 mL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety Endpoints	Incidence of Adverse Events within 30 Days After Each Vaccination	Up to 30 days after each dose

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety Endpoints	The incidence of all Serious Adverse Events (SAEs)、Adverse Events of Special Interest (AESIs) from Day 0 until 12 months after the final vaccination	from Day 0 up to 540 days
Safety Endpoints	Incidence of clinically significant abnormal electrocardiogram (ECG) findings after each vaccination.	up to 14 days

Collaborators and Investigators

• Sponsor: Changchun BCHT Biotechnology Co.

Study record dates

Study Major Dates

• Study Start (Actual): October 13, 2025
• Primary Completion (Estimated): March 4, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: September 23, 2025
• First Submitted That Met QC Criteria: January 4, 2026
• First Posted (Actual): January 9, 2026

Study Record Updates

• Last Update Posted (Actual): January 9, 2026
• Last Update Submitted That Met QC Criteria: January 4, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Genital Diseases, Male; Male Urogenital Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Infections; Virus Diseases; Genital Diseases, Female; Communicable Diseases; Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; DNA Virus Infections; Herpesviridae Infections; Herpes Simplex; Herpes Genitalis; Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Epidemiologic Studies; Epidemiologic Study Characteristics; Cohort Studies
• Other Study ID Numbers: B2101-F20240206-1

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No