A Clinical Trial to Evaluate the Safety and Immunogenicity of ACU-026-001-1-Adjuvanted CH505 Protein Nanoparticles (DV901-NP) Alone or Boosted With CH505 NP (DV902-NP) or CH505 mRNAs in Adults in Overall Good Health Without HIV
试验速览
- 阶段
- 1 期
- 状态
- 尚未招募
- 入组人数
- 54
- 试验地点
- 8
- 主要终点
- Incidence of solicited local reactogenicity
研究概览
简要总结
This Phase 1 study will evaluate the safety, tolerability, and immune responses of investigational CH505 HIV vaccine regimens in adults in overall good health without HIV. Participants will receive CH505 protein nanoparticle vaccines (DV901-NP) formulated with the investigational adjuvant ACU-026-001-1, followed by either CH505 protein nanoparticle (DV902-NP) or CH505 mRNA vaccine boosters. The study will assess the ability of these regimens to induce HIV-specific immune responses, including B-cell responses associated with the development of broadly neutralizing antibodies. An immunology cohort will also evaluate how the location of booster vaccination affects immune responses.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Sequential
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 55 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Demonstrates an understanding of the study and is able and willing to complete the informed consent process.
- •At least 18 years old at screening and up to 55 years old on day of enrollment.
- •Available for clinic follow-up through the last clinic visit and willing to be contacted 12 months after the last study product administration of ACU-026-001-
- •Willing to undergo study procedures as outlined in the schedule of procedures.
- •Agrees not to enroll in another study of an investigational agent during participation in the trial. If a potential participant is already enrolled in another clinical trial, approvals are required prior to enrollment into HVTN
- •In good general health according to the clinical judgment of the site investigator.
- •Physical examination and laboratory results without clinically significant findings that would interfere with assessment of safety or reactogenicity in the clinical judgment of the site investigator.
- •Agrees to discuss their potential for HIV acquisition and agrees to HIV prevention counseling.
- •Hemoglobin (Hgb):
- •≥11.0 g/dL for women
- •≥13.0 g/dL for men Note: If receiving exogenous hormones for more than 6 consecutive months with dosing equivalent to parenteral testosterone ≥1000 mg every 12 weeks or estradiol valerate ≥2 mg/week, determine hemoglobin eligibility based on the exogenous hormone reported.
- •White blood cell (WBC) count of 2,500 to 12,000/mm
- •WBC over 12,000/mm3 is not exclusionary if further evaluation shows general good health and if approval is granted.
- •Platelet count of 125,000 to 550,000/mm
- •Alanine aminotransferase (ALT) <2.5× the upper limit of institutional reference range.
- •Serum creatinine ≤1.1× the upper limit of normal (ULN) based on the institutional normal range.
- •Total measured serum calcium level >8.5 mg/dL (if the participant consented to have leukapheresis as a study procedure).
- •Systolic blood pressure of 90 to <140 mm Hg and diastolic blood pressure of 50 to <90 mm Hg at screening visit. The average blood pressure between the screening visit and the enrollment visit must be below 140 mm Hg systolic and 90 mmHg diastolic. A single measurement of ≥160 mm Hg systolic or ≥100 mm Hg diastolic during the current study evaluation is exclusionary.
- •Negative HIV test results by one of the following options:
- •For US volunteers:
- •Negative US Food and Drug Administration (FDA)-approved enzyme immunoassay (EIA) or chemiluminescent microparticle immunoassay (CMIA) or
- •Negative results on 2 different brands of HIV rapid tests (one of which must be FDA-approved)
- •Negative for anti-hepatitis C virus (HCV) antibodies (Abs) or negative HCV nucleic acid test (NAT) if anti-HCV Abs are detected.
- •Negative for hepatitis B surface antigen (Ag).
- •For women of pregnancy potential:
- •Must agree to use effective means of contraception from at least 21 days prior to enrollment through 8 weeks after their last scheduled vaccination timepoint.
- •Must have a negative beta human chorionic gonadotropin (β-HCG) pregnancy test (urine or serum) on day of enrollment.
- •Note: Women who have had a total hysterectomy, bilateral oophorectomy, or bilateral salpingectomy (verified by medical records), tubal ligation, or menopause (no menses for ≥1 year) are not required to undergo pregnancy testing.
- •Women of pregnancy potential must agree to not seek pregnancy through alternative methods, such as oocyte retrieval, artificial insemination, or in vitro fertilization from at least 21 days prior to enrollment through 8 weeks after their last scheduled vaccination timepoint.
排除标准
- •Woman who is breastfeeding or pregnant.
- •Body mass index (BMI) ≥
- •Enrollment of individuals with BMI ≥40 who are in good health, as assessed by the site investigator, may be considered by approval.
- •Diabetes mellitus (DM). Type 2 DM controlled with diet alone (and confirmed by HgbA1c ≤8% within the last 6 months) or a history of isolated gestational diabetes are not exclusionary. Enrollment of individuals with type 2 DM that is well controlled on hypoglycemic agent(s) may be considered on a case-by-case basis, provided that the HgbA1c is ≤8% within the last 6 months (sites may draw these at screening).
- •Previous or current recipient of an investigational HIV vaccine (previous placebo/control recipients are not excluded).
- •Receipt of non-HIV investigational vaccine(s) received within the last 1 year. Exceptions include vaccines that have subsequently undergone licensure or Emergency Use Authorization (EUA) by the FDA or World Health Organization (WHO) Emergency Use Listing (EUL), or if outside the US, by the national Regulatory Authority (RA) authorizing this clinical trial.
- •Congenital or acquired immunodeficiency, including systemic medication use likely to impair immune response to vaccine in the opinion of the site investigator, such as glucocorticoid use or prednisone dose of ≥10 mg/day, within 3 months prior to enrollment.
- •Blood products or immunoglobulin within 16 weeks prior to enrollment; receipt of immunoglobulin within 16 weeks prior to enrollment requires approval.
- •Receipt of any of the following within 4 weeks prior to enrollment:
- •Live replicating vaccine
- •Any mRNA-based vaccine with FDA licensure, FDA EUA, or WHO EUL
- •ACAM2000 vaccine more than 28 days prior with a vaccination scab still present
- •Receipt of any vaccine that is not covered in exclusion criterion #8 within 14 days prior to enrollment. Please note this includes replication-incompetent vaccines such as the Jynneos vaccine for the prevention of mpox (formerly known as monkeypox) disease.
- •History of myocarditis and/or pericarditis.
- •Initiation of Ag-based immunotherapy for allergies within the past year (stable immunotherapy is not exclusionary); inclusion of participants who initiated immunotherapy within the previous year requires approval.
- •Receipt of investigational research agents with a half-life of 7 or fewer days within 4 weeks prior to enrollment. If a potential participant has received investigational agents with a half-life of more than 7 days (or unknown half-life) within the past year, approval is required for enrollment.
- •History of serious reaction (eg, hypersensitivity, anaphylaxis) to any related vaccine, to any mRNA vaccine, including Comirnaty (Pfizer) and Spikevax (Moderna), or to any drug administered systemically as a polyethylene glycol containing LNP, including doxorubicin (Doxil, Caelyx, ThermoDox), cisplatin (Lipoplatin) and irinotecan (Onivyde).
- •Hereditary angioedema, acquired angioedema, or idiopathic forms of angioedema.
- •History of chronic urticaria, urticaria associated with previous vaccination, or any urticarial episode within the past year.
- •Bleeding disorder (eg, factor deficiency, coagulopathy, or platelet disorder requiring special precautions) diagnosed by a clinician, or current therapeutic systemic anticoagulation for any clinical indication. Systemic anticoagulation includes oral anticoagulants (eg, warfarin, dabigatran, rivaroxaban, apixaban, edoxaban), injectable anticoagulants (eg, low-molecular-weight heparin, unfractionated heparin), or other similar prescription anticoagulants.
- •History of seizure(s) within the past 3 years. Also exclude if volunteer has used medications in order to prevent or treat seizure(s) at any time within the past 3 years.
- •Asplenia or functional asplenia.
- •Active duty and reserve US military personnel.
- •Any other chronic or clinically significant condition that, in the clinical judgment of the investigator, would jeopardize the safety or rights of the study participant, including but not limited to clinically significant forms of substance use or alcohol use disorder(s), serious psychiatric disorders, any recent suicide attempt, or cancer that, in the clinical judgment of the site investigator, has potential for recurrence (excluding basal cell carcinoma).
- •Asthma is excluded if the volunteer meets any of the following criteria:
- •Required either oral or parenteral corticosteroids for an exacerbation 2 or more times within the past year
- •Needed emergency care, urgent care, hospitalization, or intubation for an acute asthma exacerbation within the past year (eg, would not exclude individuals with asthma who meet all other criteria but sought urgent/emergent care solely for asthma medication refills or coexisting conditions unrelated to asthma)
- •Uses a short-acting rescue inhaler more than 2 days per week for acute asthma symptoms (ie, not for preventive treatment prior to athletic activity)
- •Uses medium- to high-dose inhaled corticosteroids (>250 mcg fluticasone or therapeutic equivalent per day), whether in single-therapy or dual-therapy inhalers (ie, with a long-acting beta agonist [LABA])
- •Uses more than 1 medication for maintenance therapy daily. Inclusion of anyone on a stable dose of more than 1 medication for maintenance therapy daily for greater than 2 years requires approval.
- •A volunteer with a history of a potential immune-mediated medical condition (PIMMC), either active or remote. Specific examples are listed in Appendix I (AESI index). Not exclusionary: (1) remote history of Bell's palsy (>2 years ago) not associated with other neurologic symptoms; (2) mild psoriasis or other mild, uncomplicated, localized, or dermatologic condition that does not require ongoing systemic treatment; (3) remote history (>10 years ago) of Kawasaki disease without sequelae; (4) celiac disease well controlled for 6 months with diet only.
- •History of allergy to local anesthetic (Novocaine, Lidocaine).
- •Investigator concern for difficulty with venous access based on clinical history and physical examination. For example, persons with a history of intravenous drug use or substantial difficulty with previous blood draws.
研究组 & 干预措施
Group 1: DV901-NP Low-Dose Prime/DV902-NP Low-Dose Boost
Participants receive DV901-NP (100 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral intramuscular (IM) injection at Weeks 0 and 8, followed by DV902-NP (100 mcg) adjuvanted with ACU-026-001-1 (2 mg) at Weeks 16 and 24.
干预措施: DV901-NP (Biological)
Group 1: DV901-NP Low-Dose Prime/DV902-NP Low-Dose Boost
Participants receive DV901-NP (100 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral intramuscular (IM) injection at Weeks 0 and 8, followed by DV902-NP (100 mcg) adjuvanted with ACU-026-001-1 (2 mg) at Weeks 16 and 24.
干预措施: DV902-NP (Biological)
Group 1: DV901-NP Low-Dose Prime/DV902-NP Low-Dose Boost
Participants receive DV901-NP (100 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral intramuscular (IM) injection at Weeks 0 and 8, followed by DV902-NP (100 mcg) adjuvanted with ACU-026-001-1 (2 mg) at Weeks 16 and 24.
干预措施: ACU-026-001-1 (Biological)
Group 2: DV901-NP High-Dose Prime/DV902-NP High-Dose Boost
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by DV902-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) at Weeks 16 and 24.
干预措施: DV901-NP (Biological)
Group 2: DV901-NP High-Dose Prime/DV902-NP High-Dose Boost
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by DV902-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) at Weeks 16 and 24.
干预措施: DV902-NP (Biological)
Group 2: DV901-NP High-Dose Prime/DV902-NP High-Dose Boost
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by DV902-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) at Weeks 16 and 24.
干预措施: ACU-026-001-1 (Biological)
Group 3: DV901-NP Prime/CH505 mRNA Boosts
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by CH505 TF mRNA-gp160 (100 mcg) at Weeks 16 and 24 and CH505 w24 mRNA-gp160 (100 mcg) at Week 32.
干预措施: DV901-NP (Biological)
Group 3: DV901-NP Prime/CH505 mRNA Boosts
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by CH505 TF mRNA-gp160 (100 mcg) at Weeks 16 and 24 and CH505 w24 mRNA-gp160 (100 mcg) at Week 32.
干预措施: CH505 TF mRNA-gp160 (Biological)
Group 3: DV901-NP Prime/CH505 mRNA Boosts
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by CH505 TF mRNA-gp160 (100 mcg) at Weeks 16 and 24 and CH505 w24 mRNA-gp160 (100 mcg) at Week 32.
干预措施: CH505 w24 mRNA-gp160 (Biological)
Group 3: DV901-NP Prime/CH505 mRNA Boosts
Participants receive DV901-NP (300 mcg) adjuvanted with ACU-026-001-1 (2 mg) by bilateral IM injection at Weeks 0 and 8, followed by CH505 TF mRNA-gp160 (100 mcg) at Weeks 16 and 24 and CH505 w24 mRNA-gp160 (100 mcg) at Week 32.
干预措施: ACU-026-001-1 (Biological)
Group 4: Ipsilateral Prime/Contralateral Boost Immunology Cohort
Participants receive DV901-NP (150 mcg) adjuvanted with ACU-026-001-1 (1 mg) by IM injection at Weeks 0, 4, and 28. The Week 0 and Week 4 vaccinations are administered in the same deltoid (ipsilateral), and the Week 28 vaccination is administered in the opposite deltoid (contralateral).
干预措施: DV901-NP (Biological)
Group 4: Ipsilateral Prime/Contralateral Boost Immunology Cohort
Participants receive DV901-NP (150 mcg) adjuvanted with ACU-026-001-1 (1 mg) by IM injection at Weeks 0, 4, and 28. The Week 0 and Week 4 vaccinations are administered in the same deltoid (ipsilateral), and the Week 28 vaccination is administered in the opposite deltoid (contralateral).
干预措施: ACU-026-001-1 (Biological)
Group 5: Ipsilateral Prime/Ipsilateral Boost Immunology Cohort
Participants receive DV901-NP (150 mcg) adjuvanted with ACU-026-001-1 (1 mg) by IM injection at Weeks 0, 4, and 28, with all vaccinations administered in the same deltoid (ipsilateral).
干预措施: DV901-NP (Biological)
Group 5: Ipsilateral Prime/Ipsilateral Boost Immunology Cohort
Participants receive DV901-NP (150 mcg) adjuvanted with ACU-026-001-1 (1 mg) by IM injection at Weeks 0, 4, and 28, with all vaccinations administered in the same deltoid (ipsilateral).
干预措施: ACU-026-001-1 (Biological)
结局指标
主要结局
Incidence of solicited local reactogenicity
时间窗: Through 14 days after each study vaccination
Incidence and severity of solicited local reactogenicity following study vaccination.
Incidence of solicited systemic reactogenicity
时间窗: Through 14 days after each study vaccination
Incidence and severity of solicited systemic reactogenicity following study vaccination.
Incidence of adverse events
时间窗: Through 30 days after each study vaccination
Incidence of adverse events following study vaccination.
Incidence of serious adverse events
时间窗: Through 52 weeks after the last study vaccination
Incidence of serious adverse events (SAEs).
Incidence of medically attended adverse events
时间窗: Through 52 weeks after the last study vaccination
Incidence of medically attended adverse events (MAAEs).
Incidence of adverse events of special interest
时间窗: Through 52 weeks after the last study vaccination
Incidence of adverse events of special interest (AESIs)
Incidence of adverse events leading to permanent discontinuation of study product or participant withdrawal
时间窗: Through 52 weeks after the last study vaccination
Incidence of adverse events resulting in permanent discontinuation of study product administration or participant withdrawal.
Frequency of CH505M5.G458Y/GnT1neg-specific IgG+ memory B cells
时间窗: Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3)
Frequency of CH505M5.G458Y/GnT1neg-specific IgG+ memory B cells measured by flow cytometry.
Response rate of precursor-specific serum neutralizing antibodies
时间窗: Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3)
Response rate of differential serum neutralizing antibody activity against precursor detection viruses and corresponding epitope knockout viruses measured by TZM-bl assay.
Magnitude of precursor-specific serum neutralizing antibodies
时间窗: Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3)
Magnitude of differential serum neutralizing antibody activity against precursor detection viruses and corresponding epitope knockout viruses measured by TZM-bl assay.
次要结局
- Epitope specificity of HIV Env-specific serum IgG binding antibodies(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of HIV Env-specific serum IgG binding antibodies(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of HIV Env-specific serum IgG binding antibodies as measured by binding Ab multiplex assay (BAMA)(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of ferritin-specific serum IgG binding antibodies(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of ferritin-specific serum IgG binding antibodies as measured by binding Ab multiplex assay (BAMA)(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3))
- Epitope specificity of ferritin-specific serum IgG binding antibodies(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); baseline and 2 weeks after the second, fourth, and fifth vaccinations (Group 3))
- Epitope-specific antibody responses measured by EMPEM(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of antibodies blocking soluble CD4 binding to HIV Env(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of antibodies blocking soluble CD4 binding to HIV Env as measured by competition ELISA(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of antibodies blocking CH235.12 binding to HIV Env(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of antibodies blocking CH235.12 binding to HIV Env as measured by competition ELISA(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of serum neutralization against the broadly neutralizing antibody maturation panel(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of serum neutralization against the broadly neutralizing antibody maturation panel as measured by TZM-bl assay(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of serum neutralization against heterologous Tier 2 HIV-1 strains(Two weeks after the fourth vaccination (Groups 1 and 2); two weeks after the fourth and fifth vaccinations (Group 3))
- Magnitude of serum neutralization against heterologous Tier 2 HIV-1 strains(Two weeks after the fourth vaccination (Groups 1 and 2); two weeks after the fourth and fifth vaccinations (Group 3))
- Frequency of CH235-like B-cell receptor sequences(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Frequency of other CD4 binding site-like B-cell receptor sequences(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of heterologous CD4 binding site Env-specific IgG+ B cells(Baseline and 2 weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of antibodies blocking DH1029 binding to HIV Env(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of antibodies blocking DH1029 binding to HIV Env as measured by competition ELISA(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Response rate of antibodies blocking RM19R binding to HIV Env(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Magnitude of antibodies blocking RM19R binding to HIV Env as measured by competition ELISA(Two weeks after the second and fourth vaccinations (Groups 1 and 2); two weeks after the second, fourth, and fifth vaccinations (Group 3))
- Plasmablast response using B-cell sorting, single-cell RT-PCR, 10x genomics RNA sequencing(One week after the second and third vaccinations (Groups 4 and 5))
- Vaccine-specific Germinal center B-cell clonality using single cell sorting against vaccine antigen and determination of BCR sequences(One week after the second vaccination and 3 weeks after the third vaccination (Groups 4 and 5))
- Vaccine-specific Germinal center relative B-cell receptor somatic hypermutation using single cell sorting against vaccine antigen and determination of BCR sequences(One week after the second vaccination and 3 weeks after the third vaccination (Groups 4 and 5))
- Vaccine-specific Peripheral B-cell clonal diversity using single-cell sorting against vaccine antigen and determination of BCR sequences via NGS(Prior to and 9 weeks after the third vaccination (Groups 4 and 5))
- Vaccine-specific Peripheral relative B-cell receptor somatic hypermutation using single-cell sorting against vaccine antigen and determination of BCR sequences via NGS(Prior to and 9 weeks after the third vaccination (Groups 4 and 5))
- Response rate of HIV Env-specific serum IgG binding antibodies following homologous boosting(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Magnitude of HIV Env-specific serum IgG binding antibodies following homologous boosting as measured by BAMA(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Epitope specificity of HIV Env-specific serum IgG binding antibodies following homologous boosting(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Response rate of ferritin-specific serum IgG binding antibodies following homologous boosting(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Magnitude of ferritin-specific serum IgG binding antibodies following homologous boosting as measured by BAMA(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Epitope specificity of ferritin-specific serum IgG binding antibodies following homologous boosting(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Response rate of precursor-specific serum neutralizing antibodies following homologous boosting(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))
- Magnitude of precursor-specific serum neutralizing antibodies following homologous boosting as measured by TZM-bl assay(Baseline and 2 weeks after the second and third vaccinations (Groups 4 and 5))