Efficacy, reactogenicity, and safety of the adjuvanted recombinant zoster vaccine for the prevention of herpes zoster in Chinese adults ≥ 50 years: A randomized, placebo-controlled trial.

Phase III multi-country studies (ZOE-50/70) demonstrated that the adjuvanted recombinant zoster vaccine (RZV) was well tolerated and prevented herpes zoster (HZ) in healthy ≥ 50-year-olds, with a vaccine efficacy (VE) > 90% across age groups. These pivotal trials did not enroll participants from mainland China where RZV is licensed, therefore similar clinical data are missing for this population. In this phase IV observer-blind study (NCT04869982) conducted between 2021 and 2023 in China, immunocompetent and medically stable ≥ 50-year-olds were randomized 1:1 to receive two RZV or placebo doses, 2 months apart. This study assessed the VE (overall, as confirmatory objective, and descriptively by age category [50-69-year-olds/≥ 70-year-olds]), reactogenicity, and safety of RZV in this Chinese population. Of the 6138 enrolled participants, 99.2% completed the study. During a mean follow-up period of 15.2 (±1.1) months, 31 HZ episodes were confirmed (RZV = 0; placebo = 31) for an incidence rate of 0.0 vs 8.2 per 1000 person-years and an overall VE of 100% (89.82-100). The descriptive VE was 100% (85.29-100) for 50-69-year-olds and 100% (60.90-100) for ≥ 70-year-olds. Solicited adverse events (AEs) were more frequent in the RZV vs the placebo group (median duration: 1-3 days for both groups). Pain and fatigue were the most frequent local and general AEs (RZV: 72.1% and 43.4%; placebo: 9.2% and 5.3%). The frequencies of unsolicited AEs, serious AEs, potential immune-mediated diseases, and deaths were similar between both groups. RZV is well tolerated and efficacious in preventing HZ in Chinese ≥ 50-year-olds, consistent with efficacy studies including worldwide populations with similar age and medical characteristics.

What is the context? Herpes zoster, commonly known as shingles, is a painful rash resulting from the reactivation of the dormant virus causing chickenpox.Vaccines preventing shingles, such as Shingrix, were shown to be well tolerated and efficacious in healthy adults over 50 years of age from Europe, North and Latin America, Australia, and Asia (Taiwan, Hong Kong, Korea, Japan).However, data on real-world protective effect of Shingrix are limited in some regions where the vaccine is licensed for use, such as mainland China.What is new? We analyzed data from Chinese adults aged 50 years or older to determine the efficacy and safety of Shingrix.Around 6000 participants were divided in two equal groups to receive two doses of Shingrix or two doses of a placebo, given 2 months apart.We found that, during the study period, the vaccine was 100% efficacious in preventing shingles.We showed that the vaccine had an acceptable safety profile in this Chinese population.What is the impact? Shingrix is efficacious and well tolerated in Chinese adults over 50 years of age, as it is in similarly aged populations from other evaluated regions.

Clinical development of SpikoGen®, an Advax-CpG55.2 adjuvanted recombinant spike protein vaccine.

Recombinant protein vaccines represent a well-established, reliable and safe approach for pandemic vaccination. SpikoGen® is a recombinant spike protein trimer manufactured in insect cells and formulated with Advax-CpG55.2 adjuvant. In murine, hamster, ferret and non-human primate studies, SpikoGen® consistently provided protection against a range of SARS-CoV-2 variants. A pivotal Phase 3 placebo-controlled efficacy trial involving 16,876 participants confirmed the ability of SpikoGen® to prevent infection and severe disease caused by the virulent Delta strain. SpikoGen® subsequently received a marketing authorization from the Iranian FDA in early October 2021 for prevention of COVID-19 in adults. Following a successful pediatric study, its approval was extended to children 5 years and older. Eight million doses of SpikoGen® have been delivered, and a next-generation booster version is currently in development. This highlights the benefits of adjuvanted protein-based approaches which should not overlook when vaccine platforms are being selected for future pandemics.

SpikoGen is a more traditional COVID-19 vaccine comprising SARS-CoV-2 spike protein extracellular domain formulated with Advax-CpG adjuvantSpikoGen differs from the Novavax vaccine in major ways including its use of the soluble secreted spike protein ECD rather than nanoparticle formulation and the use of a different adjuvantSpikoGen demonstrates robust protection against homologous and heterologous SARS-CoV-2 strains in hamster, ferret and non-human primate challenge modelsSpikoGen induces broadly cross-neutralizing antibodies, but still protects even after these antibody levels waneIn a pivotal Phase 3 clinical trial, SpikoGen reduced the risk of severe infection by 77.5% and was not associated with myocarditis, thrombosis or any other adverse safety signalsSpikoGen received an Emergency Use Authorization in the Middle East on 6 October 2021, making it the first recombinant spike protein vaccine to achieve this milestoneEight million doses of SpikoGen vaccine have been safely delivered to dateProtein-based vaccines have a long history of reliability and safety.

Immunogenicity and safety of a recombinant Omicron BA.4/5-Delta COVID-19 vaccine ZF2202-A in Chinese adults.

BACKGROUND: The Recombinant Omicron BA.4/5-Delta COVID-19 Vaccine (ZF2202-A) is primarily designed for the Delta and Omicron BA.4/5 variants. Our objective was to assess the safety and immunogenicity of ZF2202-A in Chinese adults. METHODS: A total of 450 participants aged ≥ 18 years, who had completed primary or booster vaccination with a COVID-19 vaccine more than 6 months prior, were enrolled in this randomized, double-blind, active-controlled trial. Participants in the study and control groups were administered one dose of ZF2202-A and ZF2001, respectively. Immunogenicity subgroups were established in each group. RESULTS: At 14 days after vaccination, the seroconversion rates of Omicron BA.4/5, BF.7, and XBB.1 in the ZF2022-A group were 67.7 %, 58.6 %, and 62.6 %, with geometric mean titers (GMTs) of neutralizing antibodies at 350.2, 491.8, and 49.5, respectively. The main adverse reactions (ARs) were vaccination site pain, pruritus, fatigue, and asthenia in both the ZF2022-A group and ZF2001 group. CONCLUSIONS: The novel bivalent vaccine ZF2202-A demonstrated satisfactory immunogenicity and safety against Omicron variants as booster dose in adults with prior vaccination of COVID-19 vaccines.

Safety, immunogenicity and efficacy of the self-amplifying mRNA ARCT-154 COVID-19 vaccine: pooled phase 1, 2, 3a and 3b randomized, controlled trials.

Combination of waning immunity and lower effectiveness against new SARS-CoV-2 variants of approved COVID-19 vaccines necessitates new vaccines. We evaluated two doses, 28 days apart, of ARCT-154, a self-amplifying mRNA COVID-19 vaccine, compared with saline placebo in an integrated phase 1/2/3a/3b controlled, observer-blind trial in Vietnamese adults (ClinicalTrial.gov identifier: NCT05012943). Primary safety and reactogenicity outcomes were unsolicited adverse events (AE) 28 days after each dose, solicited local and systemic AE 7 days after each dose, and serious AEs throughout the study. Primary immunogenicity outcome was the immune response as neutralizing antibodies 28 days after the second dose. Efficacy against COVID-19 was assessed as primary and secondary outcomes in phase 3b. ARCT-154 was well tolerated with generally mild-moderate transient AEs. Four weeks after the second dose 94.1% (95% CI: 92.1-95.8) of vaccinees seroconverted for neutralizing antibodies, with a geometric mean-fold rise from baseline of 14.5 (95% CI: 13.6-15.5). Of 640 cases of confirmed COVID-19 eligible for efficacy analysis most were due to the Delta (B.1.617.2) variant. Efficacy of ARCT-154 was 56.6% (95% CI: 48.7- 63.3) against any COVID-19, and 95.3% (80.5-98.9) against severe COVID-19. ARCT-154 vaccination is well tolerated, immunogenic and efficacious, particularly against severe COVID-19 disease.

Research progress on the quality control of mRNA vaccines.

INTRODUCTION: The mRNA vaccine technologies have progressed rapidly in recent years. The COVID-19 pandemic has accelerated the application of mRNA vaccines, with research and development and clinical trials underway for many vaccines. Application of the quality by design (QbD) framework to mRNA vaccine development and establishing standardized quality control protocols for mRNA vaccines are essential for the continued development of high-quality mRNA vaccines. AREAS COVERED: mRNA vaccines include linear mRNA, self-amplifying mRNA, and circular RNA vaccines. This article summarizes the progress of research on quality control of these three types of vaccines and presents associated challenges and considerations. EXPERT OPINION: Although there has been rapid progress in research on linear mRNA vaccines, their degradation patterns remain unclear. In addition, standardized assays for key impurities, such as residual dsRNA and T7 RNA polymerase, are still lacking. For self-amplifying mRNA vaccines, a key focus should be control of stability in vivo and in vitro. For circular RNA vaccines, standardized assays, and reference standards for determining degree of circularization should be established and optimized.

Association between mRNA COVID-19 vaccine boosters and mortality in Japan: The VENUS study.

Although previous studies have shown no increased mortality risk after the primary series of COVID-19 mRNA vaccines, reports on booster doses are lacking. This study aimed to evaluate mortality risk after the mRNA vaccine boosters in addition to the primary series. This nested case-control study included two age-specific cohorts (18-64 and ≥65 years as of February 1, 2021) in two municipalities. All deaths were identified and matched five controls for each case at each date of death (index date) with risk set sampling according to municipality, age, and sex. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for mRNA vaccines (first to fifth doses) were estimated by comparing with no vaccination within 21 and 42 days before the index date using a conditional logistic regression model. The 18-64-years cohort comprised 431 cases (mean age, 57.0 years; men, 58.2%) and 2,155 controls (mean age, 56.0; men, 58.2%), whereas the ≥65-years cohort comprised 12,166 cases (84.0; 50.2%) and 60,830 controls (84.0, 50.2%). The aORs (95% CI) in 0-21 days after the third and fourth doses in the 18-64-years cohort were 0.62 (0.24, 1.62) and 0.38 (0.08, 1.84), respectively. The aORs (95% CI) after the third to fifth doses in the ≥65 years cohort were 0.36 (0.31, 0.43), 0.30 (0.25, 0.37), and 0.26 (0.20, 0.33), respectively. In conclusion, booster doses of mRNA vaccines do not increase mortality risk. These findings could help subsequent vaccine campaigns and alleviate vaccine hesitancy.

New Generation Self-Replicating RNA Vaccines Derived from Pestivirus Genome.

While mRNA vaccines have shown their worth, they have the same failing as inactivated vaccines, namely they have limited half-life, are non-replicating, and therefore limited to the size of the vaccine payload for the amount of material translated. New advances averting these problems are combining replicon RNA (RepRNA) technology with nanotechnology. RepRNA are large self-replicating RNA molecules (typically 12-15 kb) derived from viral genomes defective in at least one essential structural protein gene. They provide sustained antigen production, effectively increasing vaccine antigen payloads over time, without the risk of producing infectious progeny. The major limitations with RepRNA are RNase-sensitivity and inefficient uptake by dendritic cells (DCs), which need to be overcome for efficacious RNA-based vaccine design. We employed biodegradable delivery vehicles to protect the RepRNA and promote DC delivery. Condensing RepRNA with polyethylenimine (PEI) and encapsulating RepRNA into novel Coatsome-replicon vehicles are two approaches that have proven effective for delivery to DCs and induction of immune responses in vivo.

Safety, immunogenicity and protective effect of sequential vaccination with inactivated and recombinant protein COVID-19 vaccine in the elderly: a prospective longitudinal study.

The safety and efficacy of COVID-19 vaccines in the elderly, a high-risk group for severe COVID-19 infection, have not been fully understood. To clarify these issues, this prospective study followed up 157 elderly and 73 young participants for 16 months and compared the safety, immunogenicity, and efficacy of two doses of the inactivated vaccine BBIBP-CorV followed by a booster dose of the recombinant protein vaccine ZF2001. The results showed that this vaccination protocol was safe and tolerable in the elderly. After administering two doses of the BBIBP-CorV, the positivity rates and titers of neutralizing and anti-RBD antibodies in the elderly were significantly lower than those in the young individuals. After the ZF2001 booster dose, the antibody-positive rates in the elderly were comparable to those in the young; however, the antibody titers remained lower. Gender, age, and underlying diseases were independently associated with vaccine immunogenicity in elderly individuals. The pseudovirus neutralization assay showed that, compared with those after receiving two doses of BBIBP-CorV priming, some participants obtained immunological protection against BA.5 and BF.7 after receiving the ZF2001 booster. Breakthrough infection symptoms last longer in the infected elderly and pre-infection antibody titers were negatively associated with the severity of post-infection symptoms. The antibody levels in the elderly increased significantly after breakthrough infection but were still lower than those in the young. Our data suggest that multiple booster vaccinations at short intervals to maintain high antibody levels may be an effective strategy for protecting the elderly against COVID-19.

A universal recombinant adenovirus type 5 vector-based COVID-19 vaccine.

A universal recombinant adenovirus type-5 (Ad5) vaccine against COVID19 (Ad-US) was constructed, and immunogenicity and broad-spectrum of Ad5-US were evaluated with both intranasal and intramuscular immunization routes. The humoral immune response of Ad5-US in serum and bronchoalveolar lavage fluid were evaluated by the enzyme-linked immunosorbent assay (ELISA), recombinant vesicular stomatitis virus based pseudovirus neutralization assay, and angiotensin-converting enzyme-2 (ACE2) -binding inhibition assay. The cellular immune response and Th1/Th2 biased immune response of Ad5-US were evaluated by the IFN-γ ELISpot assay, intracellular cytokine staining, and Meso Scale Discovery (MSD) profiling of Th1/Th2 cytokines. Intramuscular priming followed by an intranasal booster with Ad5-US elicited the broad-spectrum and high levels of IgG, IgA, pseudovirus neutralizing antibody (PNAb), and Th1-skewing of the T-cell response. Overall, the adenovirus type-5 vectored universal SARS-CoV-2 vaccine Ad5-US was successfully constructed, and Ad5-US was highly immunogenic and broad spectrum. Intramuscular priming followed by an intranasal booster with Ad5-US induced the high and broad spectrum systemic immune responses and local mucosal immune responses.

The potential use of therapeutics and prophylactic mRNA vaccines in human papillomavirus (HPV).

Cervical cancer (CC) and other malignant malignancies are acknowledged to be primarily caused by persistent human papillomavirus (HPV) infection. Historically, vaccinations against viruses that produce neutralizing antibodies unique to the virus have been an affordable way to manage viral diseases. CC risk is decreased, but not eliminated, by HPV vaccinations. Since vaccinations have been made available globally, almost 90% of HPV infections have been successfully avoided. On the lesions and diseases that are already present, however, no discernible treatment benefit has been shown. As a result, therapeutic vaccines that elicit immune responses mediated by cells are necessary for the treatment of established infections and cancers. mRNA vaccines possess remarkable potential in combating viral diseases and malignancy as a result of their superior industrial production, safety, and efficacy. Furthermore, considering the expeditiousness of production, the mRNA vaccine exhibits promise as a therapeutic approach targeting HPV. Given that the HPV-encoded early proteins, including oncoproteins E6 and E7, are consistently present in HPV-related cancers and pre-cancerous lesions and have crucial functions in the progression and persistence of HPV-related diseases, they serve as ideal targets for therapeutic HPV vaccines. The action mechanism of HPV and HPV-related cancer mRNA vaccines, their recent advancements in clinical trials, and the potential for their therapeutic applications are highlighted in this study, which also offers a quick summary of the present state of mRNA vaccines. Lastly, we highlight a few difficulties with mRNA HPV vaccination clinical practice and provide our thoughts on further advancements in this quickly changing sector. It is expected that mRNA vaccines will soon be produced quickly for clinical HPV prevention and treatment.

Cross-protective efficacy and safety of an adenovirus-based universal influenza vaccine expressing nucleoprotein, hemagglutinin, and the ectodomain of matrix protein 2.

It is necessary to develop universal vaccines that act broadly and continuously to combat regular seasonal epidemics of influenza and rare pandemics. The aim of this study was to find the optimal dose regimen for the efficacy and safety of a mixture of previously developed recombinant adenovirus-based vaccines that expressed influenza nucleoprotein, hemagglutinin, and ectodomain of matrix protein 2 (rAd/NP and rAd/HA-M2e). The vaccine efficacy and safety were measured in the immunized mice with the mixture of rAd/NP and rAd/HA-M2e intranasally or intramuscularly. The minimum dose that would be efficacious in a single intranasal administration of the vaccine mixture and cross-protective efficacy against various influenza strains were examined. In addition, the immune responses that may affect the cross-protective efficacy were measured. We found that intranasal administration is an optimal route for 107 pfu of vaccine mixture, which is effective against pre-existing immunity against adenovirus. In a study to find the minimum dose with vaccine efficacy, the 106 pfu of vaccine mixture showed higher antibody titers to the nucleoprotein than did the same dose of rAd/NP alone in the serum of immunized mice. The 106 pfu of vaccine mixture overcame the morbidity and mortality of mice against the lethal dose of pH1N1, H3N2, and H5N1 influenza infections. No noticeable side effects were observed in single and repeated toxicity studies. We found that the mucosal administration of adenovirus-based universal influenza vaccine has both efficacy and safety, and can provide cross-protection against various influenza infections even at doses lower than those previously known to be effective.

Decoding trends in mRNA vaccine research: A comprehensive bibliometric study.

BACKGROUND: In recent years, infectious diseases like COVID-19 have had profound global socio-economic impacts. mRNA vaccines have gained prominence due to their rapid development, industrial adaptability, simplicity, and responsiveness to new variants. Notably, the 2023 Nobel Prize in Physiology or Medicine recognized significant contributions to mRNA vaccine research. METHODS: Our study employed a comprehensive bibliometric analysis using the Web of Science Core Collection (WoSCC) database, encompassing 5,512 papers on mRNA vaccines from 2003 to 2023. We generated cooperation maps, co-citation analyses, and keyword clustering to evaluate the field's developmental history and achievements. RESULTS: The analysis yielded knowledge maps highlighting countries/institutions, influential authors, frequently published and highly cited journals, and seminal references. Ongoing research hotspots encompass immune responses, stability enhancement, applications in cancer prevention and treatment, and combating infectious diseases using mRNA technology. CONCLUSIONS: mRNA vaccines represent a transformative development in infectious disease prevention. This study provides insights into the field's growth and identifies key research priorities, facilitating advancements in vaccine technology and addressing future challenges.

Modulation of innate immune response to mRNA vaccination after SARS-CoV-2 infection or sequential vaccination in humans.

mRNA vaccines are likely to become widely used for the prevention of infectious diseases in the future. Nevertheless, a notable gap exists in mechanistic data, particularly concerning the potential effects of sequential mRNA immunization or preexisting immunity on the early innate immune response triggered by vaccination. In this study, healthy adults, with or without documented prior SARS-CoV-2 infection, were vaccinated with the BNT162b2/Comirnaty mRNA vaccine. Prior infection conferred significantly stronger induction of proinflammatory and type I IFN-related gene signatures, serum cytokines, and monocyte expansion after the prime vaccination. The response to the second vaccination further increased the magnitude of the early innate response in both study groups. The third vaccination did not further increase vaccine-induced inflammation. In vitro stimulation of PBMCs with TLR ligands showed no difference in cytokine responses between groups, or before or after prime vaccination, indicating absence of a trained immunity effect. We observed that levels of preexisting antigen-specific CD4 T cells, antibody, and memory B cells correlated with elements of the early innate response to the first vaccination. Our data thereby indicate that preexisting memory formed by infection may augment the innate immune activation induced by mRNA vaccines.

A SARS-CoV-2 recombinant spike protein vaccine (S-268019-b) for COVID-19 prevention during the Omicron-dominant period: A phase 3, randomised, placebo-controlled clinical trial.

Clinical trials of new vaccines based on existing variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) are often impacted by the emergence of new virus variants. We evaluated the efficacy, immunogenicity, and safety of S-268019-b, a recombinant spike protein subunit vaccine based on the ancestral strain, for preventing symptomatic coronavirus disease 2019 (COVID-19) during the Omicron (BA.2)-dominant period in Vietnam. In this multicentre, phase 3, randomised (2:1), observer-blind, placebo-controlled crossover study, participants received 2 intramuscular doses (28 days apart) of either 10 µg of S-268019-b (Recombinant S-protein vaccine) or placebo. The primary endpoint was incidence of laboratory-confirmed symptomatic COVID-19 before crossover, with onset within 14 days following the second dose, in participants who were seronegative and reverse transcription polymerase chain reaction (RT-PCR)-negative at baseline. The secondary endpoints included immunogenicity and safety. In total, 8,594 participants were randomised (S-268019-b [n = 5,727]; placebo [n = 2,867]). Vaccine efficacy versus placebo was 39·1 % (95 % confidence interval [CI]:26·6-49·5; one-sided P = 0·0723). The incidence rate (95 % CI) of symptomatic COVID-19 was 776·41/1,000 person-years (682·04-880·19) in the S-268019-b group and 1272·87/1,000 person-years (1101·32-1463·57) in the placebo group. The geometric mean titres (95 % CI) of the SARS-CoV-2 neutralising antibody increased on Day 57 versus baseline with S-268019-b (34·66 [27·04-44·41] versus 2·50 (non-estimable) but not with placebo. There were no safety concerns regarding S-268019-b. S-268019-b did not demonstrate the targeted efficacy threshold against symptomatic COVID-19; however, findings were comparable with other prophylactic vaccines based on ancestor strain during the Omicron-dominant period. S-268019-b demonstrated immunogenicity and was well-tolerated. ClinicalTrials.gov identifier: NCT05212948.

Long-term stability and immunogenicity of lipid nanoparticle COVID-19 mRNA vaccine is affected by particle size.

Messenger ribonucleic acid (mRNA) technology has been rapidly applied for the development of the COVID-19 vaccine. However, naked mRNA itself is inherently unstable. Lipid nanoparticles (LNPs) protect mRNAs from extracellular ribonucleases and facilitate mRNA trafficking. For mRNA vaccines, antigen-presenting cells utilize LNPs through uptake to elicit antigen-specific immunity. There are reports on the impact of various physical characteristics of LNPs, particularly those with sizes less than 200 nm, especially 50 to 150 nm, on the overall stability and protective efficacy of mRNA vaccines. To address this, a single change in the size of LNPs using the same mRNA stock solution was assessed for the physicochemical characterization of the resulting mRNA-LNPs vaccine, along with the evaluation of their protective efficacy. Particles of smaller sizes generally disperse more effectively in solutions, with minimized occurrence of particle precipitation and aggregation. Here, we demonstrate that the vaccine containing 80-100 nm mRNA-LNPs showed the best stability and protection at 4°C and -20°C. Furthermore, we can conclude that freezing the vaccine at -20°C is more appropriate for maintaining stability over the long term. This effort is poised to provide a scientific basis for improving the quality of ongoing mRNA vaccine endeavors and providing information on the development of novel products.

Comparison of the effectiveness four years after Homo/Hetero prime-boost with 10 µg HP and 20 µg CHO recombinant hepatitis B vaccine at 1 and 6 months in maternal HBsAg-negative children.

Introduction: Limited data were available on the effectivenessfour years after Homo or Hetero prime-boost with 10 µg Hansenulapolymorpha recombinant hepatitis B vaccine (HepB-HP) and 20 µgChinese hamster ovary cell HepB (HepB-CHO). Methods: A crosssectional study was performed in maternalhepatitis B surface antigen (HBsAg)-negative children whoreceived one dose of 10 µg HepB-HP at birth, Homo or Heteroprime-boost with 10 µg HepB-HP and 20 µg HepB-CHO at 1 and 6months. HBsAg and hepatitis B surface antibody (anti-HBs) fouryears after immunization were quantitatively detected by achemiluminescent microparticle immunoassay (CMIA). Results: A total of 359 children were included; 119 childrenreceived two doses of 10 µg HepB-HP and 120 children receivedtwo doses of 20 µg HepB-CHO, called Homo prime-boost; 120children received Hetero prime-boost with 10 µg HepB-HP and 20µg HepB-CHO. All children were HBsAg negative. The geometricmean concentration (GMC) and overall seropositivity rate (SPR) ofanti-HBs were 59.47 (95%CI: 49.00 - 72.16) mIU/ml and 85.51%(307/359). Nearly 15% of the study subjects had an anti-HBsconcentration < 10 mIU/ml and 5.01% had an anti-HBsconcentration ≤ 2.5 mIU/ml. The GMC of the 20 µg CHO Homoprime-boost group [76.05 (95%CI: 54.97 - 105.19) mIU/ml] washigher than that of the 10 µg HP Homo group [45.86 (95%CI:31.94 - 65.84) mIU/ml] (p = 0.035). The GMCs of the Heteroprime-boost groups (10 µg HP-20 µg CHO and 20 µg CHO-10 µgHP) were 75.86 (95% CI: 48.98 - 107.15) mIU/ml and 43.65(95%CI: 27.54 - 69.18) mIU/ml, respectively (p = 0.041). Aftercontrolling for sex influence, the SPR of the 20 µg CHO Homoprime-boost group was 2.087 times than that of the 10 µg HPHomo group. Discussion: The HepB booster was not necessary in the generalchildren, Homo/Hetero prime-boost with 20 µg HepB-CHO wouldincrease the anti-HBs concentration four years after immunization,timely testing and improved knowledge about the self-pay vaccinewould be good for controlling hepatitis B.

A phase 3 randomized controlled trial of a COVID-19 recombinant vaccine S-268019-b versus ChAdOx1 nCoV-19 in Japanese adults.

We assessed S-268019-b, a recombinant spike protein vaccine with a squalene-based adjuvant, for superiority in its immunogenicity over ChAdOx1 nCoV-19 vaccine among adults in Japan. In this multicenter, randomized, observer-blinded, phase 3 study, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-naïve participants (aged ≥ 18 years, without prior infection or vaccination against SARS-CoV-2) were randomized (1:1) to receive either S-268019-b or ChAdOx1 nCoV-19 as two intramuscular injections given 28 days apart. Participants who provided consent for a booster administration received S-268019-b at Day 211. The primary endpoint was SARS-CoV-2 neutralizing antibody (NAb) titer on Day 57; the key secondary endpoint was the seroconversion rate for SARS-CoV-2 NAb titer on Day 57. Other endpoints included anti-SARS-CoV-2 S-protein immunoglobulin (Ig)G antibody titer and safety. The demographic and baseline characteristics were generally comparable between S-268019-b (n = 611) and ChAdOx1 nCoV-19 (n = 610) groups. S-268019-b showed superior immunogenicity over ChAdOx1 nCoV-19, based on their geometric mean titers (GMTs) and GMT ratios of SARS-CoV-2 NAb on Day 57 by cytopathic effect assay (GMT [95% confidence interval {CI}] 19.92 [18.68, 21.23] versus 3.63 [3.41, 3.87]; GMT ratio [95% CI] 5.48 [5.01, 6.00], respectively; two-sided p-values < 0.0001). Additionally, NAb measured using a cell viability assay also showed similar results (GMT [95% CI] 183.25 [168.04, 199.84] versus 24.79 [22.77, 27.00]; GMT ratio [95% CI] 7.39 [6.55, 8.35] for S-268019-b versus ChAdOx1 nCoV-19, respectively; p < 0.0001). The GMT of anti-SARS-CoV-2 S-protein IgG antibody was 370.05 for S-268019-b versus 77.92 for ChAdOx1 nCoV-19 on Day 57 (GMT ratio [95% CI] 4.75 [4.34, 5.20]). Notably, immune responses were durable through the end of the study. S-268019-b elicited T-helper 1 skewed T-cell response, comparable to that of ChAdOx1 nCoV-19. After the first dose, the incidence of solicited systemic treatment-related adverse events (TRAEs) was higher in the ChAdOx1 nCoV-19 group, but after the second dose, the incidence was higher in the S-268019-b group. Headache, fatigue, and myalgia were the most commonly reported solicited systemic TRAEs, while pain at the injection site was the most frequently reported solicited local TRAE following both doses in both groups. No serious treatment-related adverse serious TRAEs events were reported in the two groups. S-268019-b was more immunogenic than ChAdOx1 nCoV-19 vaccine and was well tolerated (jRCT2051210151).

Transplacental transfer of maternal antibodies following immunization with recombinant pertussis vaccines during pregnancy: Real-world evidence.

AIM/OBJECTIVE: This study investigates placental antibody transfer following recombinant pertussis vaccination in pregnancy in a real-world setting. METHODS: This postmarketing observational study recruited pregnant women vaccinated with monovalent recombinant acellular pertussis (aP) vaccine (aPgen; n = 199) or combined to tetanus-diphtheria (TdaPgen; n = 200), or Td-vaccine only (n = 54). Pregnancy, delivery, and neonatal outcomes were assessed. Cord blood was collected postdelivery and pertussis toxin (PT)-IgG, filamentous hemagglutinin (FHA)-IgG, and PT-neutralizing antibodies (PT-Nab) were assessed. RESULTS: No adverse pregnancy, delivery, or neonatal outcomes attributed to aPgen, TdaPgen, or Td vaccination were reported. High anti-PT antibody levels were detected in cord samples from women vaccinated with aPgen (geometric mean concentration [GMC] PT-IgG 206.1 IU/ml, 95% confidence intervals [CI]: 164.3-258.6; geometric mean titer [GMT] PT-Nab 105.3 IU/ml, 95% CI: 81.7-135.8) or TdaPgen (GMC PT-IgG 153.1 IU/ml, 95% CI: 129.1-181.5; GMT PT-Nab 81.5 IU/ml, 95% CI: 66.4-100.0). In the Td-only group, anti-PT antibodies were low (GMC PT-IgG 6.5 IU/ml, 95% CI: 4.9-8.8; GMT PT-Nab 3.8 IU/ml, 95% CI: 2.8-5.1). The same was found for FHA-IgG. Recombinant pertussis vaccination at <27 or 27-36 weeks gestation induced similar cord pertussis antibody levels. CONCLUSION: This first real-world study confirms that recombinant pertussis vaccination in the second or third trimester of pregnancy results in high levels of passive immunity in infants. Thai Clinical Trial Registry: TCTR20200528006.