Safety and immunogenicity of a heterologous boost with a recombinant vaccine, NVSI-06-07, in the inactivated vaccine recipients from UAE: a phase 2 randomised, double-blinded, controlled clinical trial

Background: The increased coronavirus disease 2019 (COVID-19) breakthrough cases pose the need of booster vaccinations. In this study, we reported the safety and immunogenicity of a heterologous boost with a recombinant COVID-19 vaccine (CHO cells), named NVSI-06-07, as a third dose in participants who have previously received two doses of the inactivated vaccine (BBIBP-CorV) at pre-specified time intervals. Using homologous boost with BBIBP-CorV as control, the safety and immunogenicity of the heterologous boost with NVSI-06-07 against various SARS-CoV-2 strains, including Omicron, were characterized. Methods: This study is a single-center, randomised, double-blinded, controlled phase 2 trial for heterologous boost of NVSI-06-07 in BBIBP-CorV recipients from the United Arab Emirates (UAE). Healthy adults (aged ≥18 years) were enrolled and grouped by the specified prior vaccination interval of BBIBP-CorV, i.e., 1-3 months, 4-6 months or ≥6 months, respectively, with 600 individuals per group. For each group, participants were randomly assigned at 1:1 ratio to receive either a heterologous boost of NVSI-06-07 or a homologous booster dose of BBIBP-CorV. The primary outcome was to comparatively assess the immunogenicity between heterologous and homologous boosts at 14 and 28 days post-boosting immunization, by evaluation of the geometric mean titers (GMTs) of IgG and neutralizing antibodies as well as the corresponding seroconversion rate (≥4-fold rise in antibody titers). The secondary outcomes were the safety profile of the boosting strategies within 30 days post vaccination. The exploratory outcome was the immune efficacy against Omicron and other variants of concern (VOCs) of SARS-CoV-2. This trial is registered with ClinicalTrials.gov, NCT05033847. Findings: A total of 1800 individuals who have received two doses of BBIBP-CorV were enrolled, of which 899 participants received a heterologous boost of NVSI-06-07 and 901 received a homologous boost for comparison. No vaccine-related serious adverse event (SAE) and no adverse events of special interest (AESI) were reported. 184 (20.47%) participants in the heterologous boost groups and 177 (19.64%) in the homologous boost groups reported at least one adverse reaction within 30 days. Most of the local and systemic adverse reactions reported were grades 1 (mild) or 2 (moderate), and there was no significant difference in the overall safety between heterologous and homologous boosts. Immunogenicity assays showed that the seroconversion rates in neutralizing antibodies against prototype SARS-CoV-2 elicited by heterologous boost were 89.96% - 97.52% on day 28 post-boosting vaccination, which was much higher than what was induced by homologous boost (36.80% - 81.75%). Similarly, in heterologous NVSI-06-07 booster groups, the neutralizing geometric mean titers (GMTs) against the prototype strain increased by 21.01 - 63.85 folds from baseline to 28 days post-boosting vaccination, whereas only 4.20 - 16.78 folds of increases were observed in homologous BBIBP-CorV booster group. For Omicron variant, the neutralizing antibody GMT elicited by the homologous boost of BBIBP-CorV was 37.91 (95%CI, 30.35-47.35), however, a significantly higher level of neutralizing antibodies with GMT 292.53 (95%CI, 222.81-384.07) was induced by the heterologous boost of NVSI-06-07, suggesting that it may serve as an effective boosting strategy combating the pandemic of Omicron. The similar results were obtained for other VOCs, including Alpha, Beta and Delta, in which the neutralizing response elicited by the heterologous boost was also significantly greater than that of the homologous boost. In the participants primed with BBIBP-CorV over 6 months, the largest increase in the neutralizing GMTs was obtained both in the heterologous and homologous boost groups, and thus the booster vaccination with over 6 months intervals was optimal. Interpretation: Our findings indicated that the heterologous boost with NVSI-06-07 was safe, well-tolerated and immunogenic in adults primed with a full regimen of BBIBP-CorV. Compared to homologous boost with a third dose of BBIBP-CorV, incremental increases in immune responses were achieved by the heterologous boost with NVSI-06-07 against SARS-CoV-2 prototype strain, Omicron variant, and other VOCs. The heterologous BBIBP-CorV/NVSI-06-07 prime-boosting vaccination may be valuable in preventing the pandemic of Omicron. The optimal booster strategy was the heterologous boost with NVSI-06-07 over 6 months after a priming with two doses of BBIBP-CorV.

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Immunogenicity and Safety of a Three-Dose Regimen of a SARS-CoV-2 Inactivated Vaccine in Adults: A Randomized, Double-blind, Placebo-controlled Phase 2 Trial

The Journal of Infectious Diseases ◽

10.1093/infdis/jiab627 ◽

2021 ◽

Author(s):

Jiankai Liu ◽

Baoying Huang ◽

Guifan Li ◽

Xianyun Chang ◽

Yafei Liu ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Controlled Trial ◽

Geometric Mean ◽

Inactivated Vaccine ◽

Phase 2 ◽

Igg Antibody ◽

Double Blind ◽

Younger Adults ◽

Live Virus ◽

Double Blind Placebo

Abstract Background Control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic needs effective vaccines. Methods In a phase 2 randomized, double-blind, placebo-controlled trial, 500 adults aged 18-59 years or ≥60 years were randomized in 2:2:1 ratio to receive 3 doses of 5-μg or 10-μg of a SARS-CoV-2 inactivated vaccine, or placebo separated by 28 days. Adverse events (AEs) were recorded through Day 28 after each dosing. Live virus or pseudovirus neutralizing antibodies, and receptor binding domain (RBD-IgG) antibody were tested after the second and third doses. Results Two doses of the vaccine elicited geometric mean titers (GMTs) of 102-119, 170-176, and 1449-1617 for the three antibodies in younger adults. Pseudovirus neutralizing and RBD-IgG GMTs were similar between older and younger adults. The third dose slightly (<1.5 folds) increased GMTs. Seroconversion percentages were 94% or more after two doses, which were generally similar after three doses. The predominant AEs were injection-site pain. All the AEs were grade 1 or 2 in intensity. No serious AE was deemed related to study vaccination. Conclusions Two doses of this vaccine induced robust immune response and had good safety profile. A third dose given 28 days after the second dose elicited limited boosting antibody response.

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Preventive Efficacy of Dried Lime (Citrus aurantifulia) in Common Cold Among Hajj Pilgrims: A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial

Galen Medical Journal ◽

10.31661/gmj.v9i0.1462 ◽

2020 ◽

Vol 9 ◽

pp. e1462

Author(s):

Mehdi Pasalar ◽

Seyed Hamdollah Mosavat ◽

Hossein Molavi Vardanjani ◽

Mohsen Keshavarz ◽

Maryam Mosaffa-Jahromi ◽

...

Keyword(s):

Clinical Trial ◽

Placebo Group ◽

Common Cold ◽

Primary Outcome Measure ◽

Drug Group ◽

Controlled Clinical Trial ◽

Significant Difference ◽

Preventive Efficacy ◽

Double Blinded ◽

Self Administered Questionnaire

Background: Dried lime (Citrus aurantifulia) is one of the herbal preparations used especially by Iranian pilgrims as a preventative agent and self-remedy for respiratory tracts symptoms in folklore medicine. Therefore, we evaluated the preventive efficacy of dried lime preparation in common cold among Iranian pilgrims. Materials and Methods: In this randomized, double-blinded, clinical trial patients in the drug group received dried lime capsules, 500 mg in a single dose per day for four weeks. In the placebo group, the patients received placebo capsules using the same method. The primary outcome measure in this trial was the severity of cold symptoms assessed by a self-administered questionnaire. Results: There were no significant differences between the two groups in terms of the trend of cold symptoms severity during the study period. However, in the second week, the severity of all the cold symptoms in the drug group was less, compared to the placebo, but at the end of the study, comparison of the two groups revealed no significant difference in any of the investigated options. Conclusion: The findings revealed that although the severity of all the cold symptoms in the drug group was less as compared to the placebo group, the dried lime capsule showed no statistically significant effect on the control of these symptoms in Iranian pilgrims. [GMJ.2020;9:e1462]

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Incidence of Infection of Enterovirus 71 and Coxsackieviruses A6 and A16 among Household Contacts of Index Cases in Dong Thap Province, Southern Vietnam

BioMed Research International ◽

10.1155/2020/9850351 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

C. Q. Hoang ◽

H. D. Nguyen ◽

N. X. Ho ◽

T. H. T. Vu ◽

T. T. M. Pham ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Geometric Mean ◽

Age Groups ◽

Enterovirus 71 ◽

Foot And Mouth Disease ◽

Household Contacts ◽

Significant Difference ◽

Antibody Titers ◽

Index Cases

Background. Scarce information exists about immunity to hand, foot, and mouth disease (HFMD) among household contacts of index cases in Vietnam and what that means for reducing ongoing HFMD transmission in the community. Methods. We analyzed neutralizing antibodies (NT) and the incidence of enterovirus (EVs) infection among household contacts of index cases in a province where HFMD remains endemic. Throat swab and 2 mL blood samples from household contacts were collected at enrollment, during and after 2 weeks follow-up. Results. The incidence of EV-A71 infection among household contacts was 40/84 (47.6%, 95% Cl: 36.9-58.3%), compared with 106/336 (31.5%, 95% Cl: 26.6-36.5%) for CV-A6 and 36/107 (33.6%, 95% Cl: 24.7-42.6%) for CV-A16. The incidence of CV-A6 infection was fairly constant across ages; in contrast, CV-A71 and CV-A16 had some variation across ages. At baseline, higher geometric mean titer (GMT) of EV-A71, CV-A6, and CV-A16 antibody titers was found for 25-34-year groups (range 216.3 to 305.0) compared to the other age groups. There was a statistically significant difference in GMT values of CV-A6 and CV-A16 between those who had an infection or did not have infection among households with an index case of these serotypes. Conclusions. Our results indicated that adults were becoming infected with HFMD and could be contributing to the transmission. There is, therefore, a need for considering the household setting as an additional target for intervention programs for HFMD.

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Brain iron chelation by deferiprone in a phase 2 randomised double-blinded placebo controlled clinical trial in Parkinson’s disease

Scientific Reports ◽

10.1038/s41598-017-01402-2 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 103

Author(s):

Antonio Martin-Bastida ◽

Roberta J. Ward ◽

Rexford Newbould ◽

Paola Piccini ◽

David Sharp ◽

...

Keyword(s):

Parkinson’S Disease ◽

Clinical Trial ◽

Parkinson's Disease ◽

Iron Chelation ◽

Controlled Clinical Trial ◽

Phase 2 ◽

Brain Iron ◽

Double Blinded

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Immunogenicity and Safety of 3 Formulations of a Respiratory Syncytial Virus Candidate Vaccine in Nonpregnant Women: A Phase 2, Randomized Trial

The Journal of Infectious Diseases ◽

10.1093/infdis/jiz395 ◽

2019 ◽

Vol 220 (11) ◽

pp. 1816-1825 ◽

Cited By ~ 1

Author(s):

Tino F Schwarz ◽

Roderick A McPhee ◽

Odile Launay ◽

Geert Leroux-Roels ◽

Jaak Talli ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Neutralizing Antibodies ◽

Geometric Mean ◽

Neutralizing Antibody ◽

Candidate Vaccine ◽

Phase 2 ◽

Serious Adverse Events ◽

Intramuscular Dose ◽

Syncytial Virus ◽

Neonates And Infants

Abstract Background Respiratory syncytial virus (RSV) is a common cause of respiratory tract illness and hospitalization in neonates and infants. RSV vaccination during pregnancy may protect offspring in their first months of life. Methods This randomized, observer-blind, multicenter, phase 2 study evaluated the immunogenicity and safety of an RSV candidate vaccine in healthy nonpregnant women aged 18–45 years. Four hundred participants were randomized (1:1:1:1) to receive a single intramuscular dose of vaccine containing 30 µg, 60 µg, or 120 µg of RSV fusion protein engineered to preferentially maintain a prefusion conformation (RSV-PreF vaccine) or placebo. Results Thirty days postvaccination, RSV-A neutralizing antibody geometric mean titers (GMTs) increased 3.75-, 4.42- and 4.36-fold; RSV-B neutralizing antibody GMTs 2.36-, 2.54- and 2.76-fold; and palivizumab competing antibody (PCA) concentrations 11.69-, 14.38- and 14.24-fold compared with baseline levels in the 30 µg, 60 µg, and 120 µg RSV-PreF groups, respectively. Antibody titers and PCA concentrations at day 30 were significantly higher with the 120 µg compared to the 30 µg RSV-PreF vaccine. All RSV-PreF vaccine formulations and the placebo had similar reactogenicity profiles. No serious adverse events were considered to be related to the RSV-PreF vaccine. Conclusions The 3 formulations of the investigational RSV-PreF vaccine were well-tolerated and induced RSV-A and RSV-B neutralizing antibodies and PCAs in healthy, nonpregnant women. Clinical Trials Registration NCT02956837.

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Validation Study of Kim's Sham Needle by Measuring Facial Temperature: An N-of-1 Randomized Double-Blind Placebo-Controlled Clinical Trial

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2012/507937 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Sanghun Lee ◽

Nara Lim ◽

Sun Mi Choi ◽

Sungchul Kim

Keyword(s):

Thermal Imaging ◽

Controlled Clinical Trial ◽

Double Blind ◽

Infrared Thermal Imaging ◽

Double Blind Placebo ◽

Control Intervention ◽

Significant Difference ◽

Double Blinded ◽

Stimulation Of

Introduction. In 2008, Kim's sham needle was developed to improve the quality of double-blinded studies. The aim of this study is to validate Kim's sham needle by measuring facial temperature.Methods. We designed “N-of-1” trials involving 7 smokers. One session was composed of 2 stimulations separated by a 2 h washout period. Six sessions were applied daily for all subjects. Infrared thermal imaging was used to examine the effects of acupuncture (HT8, KI2) on facial temperature following smoking-induced decrease.Results. All subjects demonstrated decreased temperatures after sham needle treatment, but 5 of the 7 subjects showed increased temperatures after real needle treatment. 6 of the 7 subjects showed a significant difference(P<0.05)between treatments with real and sham needles. Thus, the physiological stimulation of Kim's sham needle is different from that of a real needle, suggesting that Kim's sham needle is a potential inactive control intervention.

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Neutralization of SARS-CoV-2 Omicron variant by sera from BNT162b2 or Coronavac vaccine recipients

10.1101/2021.12.13.21267668 ◽

2021 ◽

Author(s):

Lu Lu ◽

Bobo Mok ◽

Linlei Chen ◽

Jacky Chan ◽

Owen Tsang ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Geometric Mean ◽

Neutralizing Antibody ◽

World Health ◽

Whole Genome Sequence ◽

Live Virus ◽

Significant Difference ◽

Antibody Titers ◽

Ancestral Virus ◽

Health Organization

Background The SARS-CoV-2 Omicron variant, designated as a Variant of Concern(VOC) by the World Health Organization, carries numerous spike protein mutations which have been found to evade neutralizing antibodies elicited by COVID-19 vaccines. The susceptibility of Omicron variant by vaccine-induced neutralizing antibodies are urgently needed for risk assessment. Methods Omicron variant strains HKU691 and HKU344-R346K were isolated from patients using TMPRSS2-overexpressing VeroE6 cells. Whole genome sequence was determined using nanopore sequencing. Neutralization susceptibility of ancestral lineage A virus and the Omicron, Delta and Beta variants to sera from 25 BNT162b2 and 25 Coronavac vaccine recipients was determined using a live virus microneutralization assay. Results The Omicron variant strain HKU344-R346K has an additional spike R346K mutation, which is present in 8.5% of strains in GISAID database. Only 20% and 24% of BNT162b2 recipients had detectable neutralizing antibody against the Omicron variant HKU691 and HKU344-R346K, respectively, while none of the Coronavac recipients had detectable neutralizing antibody titer against either Omicron isolates. For BNT162b2 recipients, the geometric mean neutralization antibody titers(GMT) of the Omicron variant isolates(5.43 and 6.42) were 35.7-39.9-fold lower than that of the ancestral virus(229.4), and the GMT of both omicron isolates were significantly lower than those of the beta and delta variants. There was no significant difference in the GMT between HKU691 and HKU344-R346K. Conclusions Omicron variant escapes neutralizing antibodies elicited by BNT162b2 or CoronaVac. The additional R346K mutation did not affect the neutralization susceptibility. Our data suggest that the Omicron variant may be associated with lower COVID-19 vaccine effectiveness.

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Safety and immunogenicity of inactivated SARS-CoV-2 vaccine in high-risk occupational population: a randomized, parallel, controlled clinical trial

Infectious Diseases of Poverty ◽

10.1186/s40249-021-00924-2 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Yongliang Feng ◽

Jing Chen ◽

Tian Yao ◽

Yue Chang ◽

Xiaoqing Li ◽

...

Keyword(s):

Clinical Trial ◽

High Risk ◽

Neutralizing Antibodies ◽

Health Care Systems ◽

Controlled Trial ◽

Geometric Mean ◽

Neutralizing Antibody ◽

Shanxi Province ◽

Controlled Clinical Trial ◽

Clinical Trial Registry

Abstract Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the resulting coronavirus disease 2019 (COVID-19) have a substantial burden on health-care systems around the world. This is a randomized parallel controlled trial for assessment of the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine, aiming to determine an appropriate vaccination interval of the vaccine for high-risk occupational population. Methods In an ongoing randomized, parallel, controlled phase IV trial between January and May 2021 in Taiyuan City, Shanxi Province, China, we randomly assigned the airport ground staff and public security officers aged 18 to 59 years to receive two doses of inactivated SARS-CoV-2 vaccine at 14 days, 21 days, or 28 days. The serum neutralizing antibody to live SARS-CoV-2 was performed at baseline and 28 days after immunization. Long-term data are being collected. The primary immunogenicity endpoints were neutralization antibody seroconversion and geometric mean titer (GMT) at 28 days after the second dose. Analysis of variance (ANOVA), chi-square, and logistic regression analysis were used for data analysis. Results A total of 809 participants underwent randomization and received two doses of injections: 270, 270, 269 in the 0–14, 0–21, and 0–28 vaccination group, respectively. By day 28 after the second injection, SARS-CoV-2 neutralizing antibody of GMT was 98.4 (95% CI: 88.4–108.4) in the 0–14 group, which was significantly lower compared with 134.4 (95% CI: 123.1–145.7) in the 0–21 group (P < 0.001 vs 0–14 group) and 145.5 (95% CI: 131.3–159.6) in the 0–28 group (P < 0.001 vs 0–14 group), resulting in the seroconversion rates to neutralizing antibodies (GMT ≥ 16) of 100.0% for all three groups, respectively. The intention-to-treat (ITT) analysis yielded similar results. All reported adverse reactions were mild. Conclusions Both a two-dose of inactivated SARS-CoV-2 vaccine at 0–21 days and 0–28 days regimens significantly improved SARS-CoV-2 neutralizing antibody level compared to the 0–14 days regimen in high-risk occupational population, with seroconversion rates of 100.0%. Trial registration Chinese Clinical Trial Registry, ChiCTR2100041705, ChiCTR2100041706. Registered 1 January 2021, www.chictr.org.cn. Graphical Abstract

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Synbiotics and Treatment of Asthma: A Double-Blinded, Randomized, Placebo-Controlled Clinical Trial

10.31661/gmj.v8i0.1350 ◽

2019 ◽

Vol 8 ◽

pp. 1350

Author(s):

Maryam Hassanzad ◽

Keyvan Maleki Mostashari ◽

Hosseinali Ghaffaripour ◽

Habib Emami ◽

Samane Rahimi limouei ◽

...

Keyword(s):

Clinical Trial ◽

Side Effects ◽

Control Group ◽

Controlled Clinical Trial ◽

Positive Effects ◽

Outpatient Visits ◽

Significant Difference ◽

Asthma In Children ◽

Double Blinded ◽

Experimental Group

Background: We examined the efficiency and safety of a specific synbiotic compound, brand name Kidilact®, in the treatment of asthma in children 12 years of age or younger. Materials and Methods: This double-blinded, randomized, placebo-controlled clinical trial was conducted in Tehran, Iran, from May 22, 2016, to May 21, 2017. One hundred children, 12 years of age or younger, who suffered from mild to moderate asthma were recruited in this study. The subjects were randomly divided into two groups; the experimental group received a sachet of Kidilact®, and the control group received a sachet of placebo once a day for six months. Both groups were compared in terms of the frequency of asthma attacks that were severe enough to require administration of fast-acting medications, the number of outpatient visits for asthma-related problems, and the frequency of hospitalization due to exacerbated symptoms of asthma. Results: There were fewer complaints of drug-induced side effects, e.g., vomiting, headache, stomachache, and diarrhea, exacerbated cough, and constipation in the experimental group than in the control group. Overall, a significantly greater number of participants in the experimental group were satisfied with the therapeutic intervention than those in the control group, as verified by the participants and their parents/guardians self-report. There was no significant difference between both groups in the frequency of asthma attacks and hospitalization due to exacerbated symptoms of asthma. The only significant difference between both groups was the count of outpatient visits. While the control group made 55 outpatient visits to the hospital, participants in the experimental group visited the hospital only 19 times (P=0.001). Conclusion: Results of our study indicates that synbiotic compound Kidilact® generally alleviates the symptoms of asthma in children of 12 years of age or younger, resulting in less frequent outpatient visits to the hospital due to asthma-related problems while rarely causing any side effects. Due to ease of use, the rarity of side effects, and their indirect positive effects on quality of life of asthmatic patients, we recommend that synbiotics be incorporated in regular treatment and management of children with asthma. [GMJ.2019;8:e1350]

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Early immune response in mice immunized with a semi-split inactivated vaccine against SARS-CoV-2 containing S protein-free particles and subunit S protein

10.1101/2020.11.03.366641 ◽

2020 ◽

Author(s):

Marek Petráš ◽

Petr Lesný ◽

Jan Musil ◽

Radomíra Limberková ◽

Alžběta Pátíková ◽

...

Keyword(s):

Cellular Immunity ◽

Neutralizing Antibodies ◽

Immune Cell ◽

Geometric Mean ◽

Inactivated Vaccine ◽

S Protein ◽

Humoral And Cellular Immunity ◽

Wide Range ◽

Immune Cell Response ◽

Th1 And Th2 Lymphocytes

AbstractThe development of a vaccine against COVID-19 is a hot topic for many research laboratories all over the world. Our aim was to design a semi-split inactivated vaccine offering a wide range of multi-epitope determinants important for the immune system including not only the spike (S) protein but also the envelope, membrane and nucleocapsid proteins. We designed a semi-split vaccine prototype consisting of S protein-depleted viral particles and free S protein. Next, we investigated its immunogenic potential in BALB/c mice. The animals were immunized intradermally or intramuscularly with the dose adjusted with buffer or addition of aluminum hydroxide, respectively. The antibody response was evaluated by plasma analysis at 7 days after the first or second dose. The immune cell response was studied by flow cytometry analysis of splenocytes. The data showed a very early onset of both S protein-specific antibodies and virus-neutralizing antibodies at 90% inhibition regardless of the route of vaccine administration. However, significantly higher levels of neutralizing antibodies were detected in the intradermally (geometric mean titer - GMT of 7.8 ± 1.4) than in the intramuscularly immunized mice (GMT of 6.2 ± 1.5). In accordance with this, stimulation of cellular immunity by the semi-split vaccine was suggested by elevated levels of B and T lymphocyte subpopulations in the murine spleens. These responses were more predominant in the intradermally immunized mice compared with the intramuscular route of administration. The upward trend in the levels of plasmablasts, memory B cells, Th1 and Th2 lymphocytes, including follicular helper T cells, was confirmed even in mice receiving the vaccine intradermally at a dose of 0.5 μg.We demonstrated that the semi-split vaccine is capable of eliciting both humoral and cellular immunity early after vaccination. Our prototype thus represents a promising step toward the development of an efficient anti-COVID-19 vaccine for human use.

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