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A Study to Evaluate the Safety and Immunogenicity of a Single Dose of H1ssF-3928 mRNA-LNP in Healthy Adults

A Phase 1, Open-Label, Comparator-Controlled, Dose-Escalation Study to Evaluate the Safety and Immunogenicity of a Single Dose of VRC H1ssF-3928 mRNA-LNP in Healthy Adults

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05755620
Enrollment
50
Registered
2023-03-06
Start date
2023-04-05
Completion date
2025-10-03
Last updated
2025-10-31

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Influenza

Keywords

Comparator-Controlled, Dose-Escalation, H1ssF-3928, Healthy Adults, mRNA-LNP, Phase 1

Brief summary

This is a Phase 1, single-site, open-label, comparator-controlled dose escalating study of an intramuscularly (IM) administered mRNA-LNP vaccine encoding for (Vaccine Research Center) VRC H1ssF 3928 of up to 50 healthy adult volunteers aged 18 to 49 years, inclusive. This study is designed to assess the safety and immunogenicity of one dose of H1ssF 3928 mRNA Vaccine. Eligible participants will be sequentially enrolled into dosing groups (10 mcg, 25 mcg, and 50 mcg, selected optimal dose) to receive the H1ssF 3928 mRNA Vaccine at the specified dose. A separate group of 10 participants will receive licensed quadrivalent influenza vaccine (IIV4). Subjects receiving IIV4 will be followed for safety but only their immune responses will be compared to those of participants receiving H1ssF 3928 mRNA Vaccine. Dosing of H1ssF 3928 mRNA Vaccine will commence at the lowest dose (10 mcg) and only escalate to the next highest dose if safety concerns are not identified. Up to ten subjects will be enrolled per dosing cohort. Reactogenicity and adverse event (AE) information through Day 7 and clinical laboratory results through Day 8 from the first three dosing groups will guide the selection of an optimal dose group to include 10 subjects who will receive the optimal dose of mRNA-LNP. The primary objective of this study is to assess the safety of a single dose of VRC H1ssF 3928 mRNA-LNP vaccine administered IM in healthy adults, 18-49 yrs, at doses of 10 mcg, 25 mcg, and 50 mcg.

Detailed description

This is a Phase 1, single-site, open-label, comparator-controlled dose escalating study of an intramuscularly (IM) administered mRNA-LNP vaccine encoding for (Vaccine Research Center) VRC H1ssF 3928 of up to 50 healthy adult volunteers aged 18 to 49 years, inclusive. This study is designed to assess the safety and immunogenicity of one dose of H1ssF 3928 mRNA Vaccine. Eligible participants will be sequentially enrolled into dosing groups (10 mcg, 25 mcg, and 50 mcg, selected optimal dose) to receive the H1ssF 3928 mRNA Vaccine at the specified dose. A separate group of 10 participants will receive licensed quadrivalent influenza vaccine (IIV4). Subjects receiving IIV4 will be followed for safety but only their immune responses will be compared to those of participants receiving H1ssF 3928 mRNA Vaccine. Dosing of H1ssF 3928 mRNA Vaccine will commence at the lowest dose (10 mcg) and only escalate to the next highest dose if safety concerns are not identified. For each VRC H1ssF 3928 mRNA-LNP (Lipid Nanoparticle) dosing group, the first two subjects enrolled will be considered the sentinel subgroup. After the two subjects in the Low Dose sentinel subgroup are enrolled and given their vaccination, enrollment will then be stopped pending a review of the reactogenicity and safety data collected through Day 3 for both subjects. Approval by the reviewing group will allow for continued enrollment of the remaining Low Dose Group subjects to complete enrollment of 10 participants. After Low Dose Group enrollment is completed, enrollment will be stopped pending an Safety Review Committee (SRC) review of the reactogenicity and adverse event (AE) information through Day 7 and clinical laboratory results through Day 8 for all Low Dose Group subjects. Approval will allow dose escalation and initiation of enrollment of the Medium Dose Group sentinel subgroup. After the two subjects in the Medium Dose sentinel subgroup are enrolled and given their vaccination, enrollment will then be stopped pending a safety review of the sentinel subgroup as specified for the Low Dose Group. Approval will allow for continued enrollment of Medium Dose Group subjects to complete enrollment of 10 participants. After the Medium Dose Group enrollment is completed, enrollment will be stopped pending an SRC review of the reactogenicity and adverse event information through Day 7 and clinical laboratory results through Day 8 for all Medium Dose Group subjects. Approval will allow dose escalation and initiation of enrollment of the High Dose Group sentinel subgroup. After the two subjects in the High Dose sentinel subgroup are enrolled and given their vaccination, enrollment will then be stopped pending a safety review of the sentinel subgroup as specified for the Low and Medium Dose Groups. Approval will allow for continued enrollment of High Dose Group subjects to complete enrollment of 10 participants. After the High Dose Group enrollment is completed, enrollment will be stopped pending an SRC review of the reactogenicity and adverse event information through Day 7 visit and clinical laboratory results through Day 8 for all High Dose Group subjects. Reactogenicity and AE information through Day 7 and clinical laboratory results through Day 8 from the first three dosing groups will guide the selection of an optimal dose group to include an additional 10 subjects who will receive the optimal dose of mRNA-LNP. The primary objective of this study is to assess the safety of a single dose of VRC H1ssF 3928 mRNA-LNP vaccine administered IM in healthy adults, 18-49 yrs, at doses of 10 mcg, 25 mcg, and 50 mcg. The secondary objective of this study is to assess serum antibody responses to a single dose of VRC H1ssF 3928 mRNA-LNP vaccine administered IM in healthy adults at doses of 10 mcg, 25 mcg, and 50 mcg in comparison to a standard dose of IIV4.

Interventions

A seasonal quadrivalent inactivated influenza vaccine (IIV4), prepared from influenza viruses propagated in embryonated chicken eggs, protecting against 2 influenza A subtypes and 2 influenza B subtypes.

0.9% Sodium Chloride Injection

The vaccine consists of modified nucleoside messenger RNA (mRNA) encapsulated in lipid nanoparticles (LNP), comprised of four lipid components: (ALC-307 (ionizable lipid), DSPC, cholesterol, and ALC-0159 \[PEG lipid\]).

Sponsors

National Institute of Allergy and Infectious Diseases (NIAID)
Lead SponsorNIH

Study design

Allocation
NON_RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 49 Years
Healthy volunteers
Yes

Inclusion criteria

1. Provide written informed consent prior to initiation of any study procedure. 2. Are able to understand and comply with planned study procedures and be available for all study visits. 3. Are males or non-pregnant, non-breastfeeding females, 18 to 49 years of age, inclusive at time of screening and enrollment. 4. Must agree to collection of venous blood and nasal absorption specimens per protocol and enrollment in DMID Protocol No. 19-0025 biorepository protocol for secondary research and use of residual biologic specimens. 5. Are in good health\* and do not have clinically significant medical, psychiatric, chronic or intermittent health conditions including those listed in

Exclusion criteria

(Section 1). \*As determined by medical history, medication use, and physical examination to evaluate ongoing chronic medical or psychiatric diagnoses or conditions, defined as those that have been present for at least 90 days, which would not affect the assessment of the safety of subjects or the immunogenicity of study vaccinations. These medical diagnoses or conditions should be stable for the last 60 days (no hospitalizations, emergency room \[ER\] or urgent care for condition \[excluding musculoskeletal conditions\], or invasive medical procedure and no adverse symptoms that need medical intervention such as medication change/supplemental oxygen). This includes no change in chronic prescription medication, dose or in the 60 days prior to enrollment. Any prescription change that is due to change of health care provider, insurance company, etc., or that is done for financial reasons, as long as in the same class of medication, will not be considered a deviation of this inclusion criterion. Subjects may be on chronic or as needed (prn) medications if, in the opinion of the site PI or appropriate sub-investigator, they pose no additional risk to subject safety or assessment of reactogenicity and immunogenicity and do not indicate a worsening or treatment of continued symptoms of medical diagnosis or condition. Note: Low dose topical, corticosteroids as outlined in the Subject

Design outcomes

Primary

MeasureTime frameDescription
Occurrence of solicited reactogenicity adverse events (AEs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 14Both local and systemic adverse events will be assessed
Occurrence of any influenza-like illnesses (ILIs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 366
Occurrence of any new-onset chronic medical conditions (NOCMCs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 366
Occurrence of any serious adverse events (SAEs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 366
Occurrence of any unsolicited adverse events (AEs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 28
Occurrence of clinical laboratory adverse events (AEs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 57
Occurrence of medically attended adverse events (MAAEs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 366
Occurrence of adverse events of special interest (AESIs) corresponding to myocarditis, pericarditis, or myopericarditis with VRC H1ssF_3928 mRNA-LNP vaccineDay 1 through Day 57
Occurrence of any adverse events of special interest (AESIs) with VRC H1ssF_3928 mRNA-LNP vaccine.Day 1 through Day 366adverse events of special interest (AESIs) corresponding to Grade 2 or greater decrease in lymphocyte or neutrophil count

Secondary

MeasureTime frame
Geometric mean fold rise (GMFR) of homologous H1-specific neutralizing antibodies in a reporter microneutralization assay.Day 1 through Day 57
Geometric mean fold rise (GMFR) of homologous H1-specific neutralizing antibodies in a viral microneutralization assay.Day 1 through Day 57
Geometric mean titers (GMT) of homologous H1-specific neutralizing antibodies in a reporter microneutralization assay.Day 1 through Day 57
Geometric mean titers (GMT) Of homologous H1-specific neutralizing antibodies in a viral microneutralization assay.Day 1 through Day 57
Geometric mean titers of anti-stalk serum antibodies measured by enzyme linked immunosorbent assay (ELISA).Day 1 through Day 57
Geometric mean fold rise (GMFR) of anti-stalk serum antibodies measured by enzyme linked immunosorbent assay (ELISA).Day 1 through Day 57

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026