Safety and immunogenicity of a novel recombinant adenovirus type-5 vector-based Ebola vaccine in healthy adults in China: preliminary report of a randomised, double-blind, placebo-controlled, phase 1 trial.

BACKGROUND: Up to now, all tested Ebola virus vaccines have been based on the virus strain from the Zaire outbreak in 1976. We aimed to assess the safety and immunogenicity of a novel recombinant adenovirus type-5 vector-based Ebola vaccine expressing the glycoprotein of the 2014 epidemic strain. METHODS: We did this randomised, double-blind, placebo-controlled, phase 1 clinical trial at one site in Taizhou County, Jiangsu Province, China. Healthy adults (aged 18-60 years) were sequentially enrolled and randomly assigned (2:1), by computer-generated block randomisation (block size of six), to receive placebo, low-dose adenovirus type-5 vector-based Ebola vaccine, or high-dose vaccine. Randomisation was pre-stratified by dose group. All participants, investigators, and laboratory staff were masked to treatment allocation. The primary safety endpoint was occurrence of solicited adverse reactions within 7 days of vaccination. The primary immunogenicity endpoints were glycoprotein-specific antibody titres and T-cell responses at day 28 after the vaccination. Analysis was by intention to treat. The study is registered with ClinicalTrials.gov, number NCT02326194. FINDINGS: Between Dec 28, 2014, and Jan 9, 2015, 120 participants were enrolled and randomly assigned to receive placebo (n=40), low-dose vaccine (n=40), or high-dose vaccine. Participants were followed up for 28 days. Overall, 82 (68%) participants reported at least one solicited adverse reaction within 7 days of vaccination (n=19 in the placebo group vs n=27 in the low-dose group vs n=36 in the high-dose group; p=0·0002). The most common reaction was mild pain at the injection site, which was reported in eight (20%) participants in the placebo group, 14 (35%) participants in the low-dose group, and 29 (73%) participants in the high-dose vaccine group (p<0·0001). We recorded no statistical differences in other adverse reactions and laboratory tests across groups. Glycoprotein-specific antibody titres were significantly increased in participants in the low-dose and high-dose vaccine groups at both day 14 (geometric mean titre 421·4 [95% CI 249·7-711·3] and 820·5 [598·9-1124·0], respectively; p<0·0001) and day 28 (682·7 [424·3-1098·5] and 1305·7 [970·1-1757·2], respectively; p<0·0001). T-cell responses peaked at day 14 at a median of 465·0 spot-forming cells (IQR 180·0-1202·5) in participants in the low-dose group and 765·0 cells (400·0-1460·0) in those in the high-dose group. 21 (18%) participants had mild fever (n=9 in the placebo group, n=6 in the low-dose group, and n=6 in the high-dose group). No serious adverse events were recorded. INTERPRETATION: Our findings show that the high-dose vaccine is safe and robustly immunogenic. One shot of the high-dose vaccine could mount glycoprotein-specific humoral and T-cell response against Ebola virus in 14 days. FUNDING: China National Science and Technology, Beijing Institute of Biotechnology, and Tianjin CanSino Biotechnology.

Immunogenicity and safety of an enterovirus 71 vaccine in healthy Chinese children and infants: a randomised, double-blind, placebo-controlled phase 2 clinical trial.

BACKGROUND: Enterovirus 71 (EV71) outbreaks are a socioeconomic burden, especially in the western Pacific region. Results of phase 1 clinical trials suggest an EV71 vaccine has a clinically acceptable safety profile and immunogenicity. We aimed to assess the best possible dose and formulation, immunogenicity, and safety profile of this EV71 vaccine in healthy Chinese children. METHODS: This randomised, double-blind, placebo-controlled, phase 2 trial was undertaken at one site in Donghai County, Jiangsu Province, China. Eligible participants were healthy boys or girls aged 6­36 months. Participants were randomly assigned (1:1:1:1:1) to receive either 160 U, 320 U, or 640 U alum-adjuvant EV71 vaccine, 640 U adjuvant-free EV71 vaccine, or a placebo (containing alum adjuvant only), according to a blocked randomisation list generated by SAS 9.1. Participants and investigators were masked to the assignment. The primary endpoint was anti-EV71 neutralising antibody geometric mean titres (GMTs) at day 56, analysed according to protocol. The study is registered with ClinicalTrials.gov, number NCT01399853. FINDINGS: We randomly assigned 1200 participants, 240 (120 aged 6­11 months [infants] and 120 aged 12­36 months [children]) of whom were assigned to each dose. 1106 participants completed the study and were included in the according-to-protocol analysis. The main reasons for dropout were withdrawal of consent and refusal to donate a blood sample. Infants who received the 640 U adjuvant vaccine had the highest GMTs on day 56 (742·2 [95% CI 577·3­954·3]), followed by those who received the 320 U formulation (497·9 [383·1­647·0]). For children, those who received the 320 U formulation had the highest GMTs on day 56 (1383·2 [1037·3­1844·5]). Participants who received the vaccine had significantly higher GMTs than did who received placebo (p<0·0001). For the subgroup of participants who were seronegative at baseline, both infants and children who received the 640 U adjuvant vaccine had the highest GMTs on day 56 (522·8 [403·9­676·6] in infants and 708·4 [524·1­957·6] in children), followed by those who received the 320 U adjuvant vaccine (358·2 [280·5­457·5] in infants and 498·0 [383·4­646·9] in children). 549 (45·8%) of 1200 participants (95 CI 42·9­48·6%) reported at least one injection-site or systemic adverse reaction, but the incidence of adverse reactions did not differ significantly between groups (p=0·36). The 640 U alum-adjuvant vaccine group had a significantly higher incidence of induration than did the 640 U adjuvant-free group (p=0·001). INTERPRETATION: Taking immunogenicity, safety, and production capacity into account, the 320 U alum-adjuvant formulation of the EV71 vaccine is probably the best possible formulation for phase 3 trials. FUNDING: The National Science and Technology Major Project (2011ZX10004-902) of the Chinese Ministry of Science and Technology, China's 12­5 National Major Infectious Disease Program (2012ZX10002-001), and Beijing Vigoo Biological.

Efficacy, safety, and immunology of an inactivated alum-adjuvant enterovirus 71 vaccine in children in China: a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: A vaccine for enterovirus 71 (EV71) is needed to address the high burden of disease associated with infection. We assessed the efficacy, safety, immunogenicity, antibody persistence, and immunological correlates of an inactivated alum-adjuvant EV71 vaccine. METHODS: We did a randomised, double-blind, placebo-controlled, phase 3 trial. Healthy children aged 6-35 months from four centres in China were randomly assigned (1:1) to receive vaccine or alum-adjuvant placebo at day 0 and 28, according to a randomisation list (block size 30) generated by an independent statistician. Investigators and participants and their guardians were masked to the assignment. Primary endpoints were EV71-associated hand, foot, and mouth disease (HFMD) and EV71-associated disease during the surveillance period from day 56 to month 14, analysed in the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT01508247. FINDINGS: 10,245 participants were enrolled and assigned: 5120 to vaccine versus 5125 to placebo. 4907 (with three cases of EV71-associated HFMD and eight cases of EV71-associated disease) versus 4939 (with 30 cases of EV71-associated HFMD and 41 cases of EV71-associated disease) were included in the primary efficacy analysis. Vaccine efficacy was 90·0% (95% CI 67·1-96·9) against EV71-associated HFMD (p=0·0001) and 80·4% (95% CI 58·2-90·8) against EV71-associated disease (p<0·0001). Serious adverse events were reported by 62 of 5117 (1·2%) participants in the vaccine group versus 75 of 5123 (1·5%) in the placebo group (p=0·27). Adverse events occurred in 3644 (71·2%) versus 3603 (70·3%; p=0·33). INTERPRETATION: EV71 vaccine provides high efficacy, satisfactory safety, and sustained immunogenicity. FUNDING: China's 12-5 National Major Infectious Disease Program, Beijing Vigoo Biological.

A novel influenza A (H1N1) vaccine in various age groups.

BACKGROUND: There is an urgent need for a vaccine that is effective against the 2009 pandemic influenza A (H1N1) virus. METHODS: A split-virus, inactivated candidate vaccine against the 2009 H1N1 virus was manufactured, and we evaluated its safety and immunogenicity in a randomized clinical trial. Subjects were between 3 and 77 years of age, stratified into four age groups. The immunization schedule consisted of two vaccinations, 21 days apart. Subjects were injected with placebo or with vaccine, with or without alum adjuvant, at doses of 7.5 microg, 15 microg, or 30 microg. Serologic analysis was performed at baseline and on days 21 and 35. RESULTS: A total of 2200 subjects received one dose, and 2103 (95.6%) received the second dose, of vaccine or placebo. No severe adverse side effects associated with the vaccine were noted. In the nonadjuvanted-vaccine groups, injection-site or systemic reactions, most mild in nature, were noted in 5.5 to 15.9% of subjects. Among the subjects receiving 15 microg of nonadjuvanted vaccine, a hemagglutination-inhibition titer of 1:40 or more was achieved by day 21 in 74.5% of subjects between 3 and 11 years of age, 97.1% of subjects between 12 and 17 years, 97.1% of subjects between 18 and 60 years, and 79.1% of subjects 61 years of age or older; by day 35, the titer had been achieved in 98.1%, 100%, 97.1%, and 93.3% of subjects, respectively. The proportion with a titer of 1:40 or more was generally highest among the subjects receiving 30 microg of vaccine, with or without adjuvant. Vaccine without adjuvant was associated with fewer local reactions and greater immune responses than was vaccine with adjuvant. CONCLUSIONS: These data suggest that a single dose of 15 microg of hemagglutinin antigen without alum adjuvant induces a typically protective immune response in the majority of subjects between 12 and 60 years of age. Lesser immune responses were seen after a single dose of vaccine in younger and older subjects. (ClinicalTrials.gov number, NCT00975572).

Immunogenicity and safety of human diploid cell vaccine (HDCV) vs. purified Vero cell vaccine (PVRV) vs. purified chick embryo cell vaccine (PCECV) used in post-exposure prophylaxis: a systematic review and meta-analysis.

This study comprehensively evaluated and compared three human rabies vaccines. Seven electronic databases were systematically searched. The Cochrane Handbook v5.1.0 was used to assess the risk of bias. A random-effects model was used to combine individual rates, and network meta-analysis was used for pairwise comparisons. Twenty-seven articles were included, with a total of 18,630 participants. The pooled incidence of the total adverse reaction to HDCV was significantly lower than that of PCECV. HDCV administration resulted in a lower incidence of local pain, fever, and weakness than purified Vero cell vaccine. HDCV caused a lower incidence of local pain and fever than PCECV. No significant difference was observed in terms of the seroconversion rate on day 7 or the rabies virus-neutralizing antibody titer on day 14. HDCV demonstrated superiority in terms of safety compared with the other two rabies vaccines, while the same was not observed in terms of immunogenicity.

Evaluation of a recombinant five-antigen Staphylococcus aureus vaccine: The randomized, single-centre phase 1a/1b clinical trials.

BACKGROUND: Staphylococcus aureus is an important pathogen that causes hospital and community infections. To control Staphylococcus aureus infection and reduce the usage of antibiotics, we evaluated the safety and immunogenicity of a recombinant five-antigen Staphylococcus aureus vaccine (rFSAV) in healthy adults. METHODS: We conducted a randomized, double-blind, placebo-controlled phase 1a study and a randomized, open-label phase 1b study. In phase 1a, we randomly allocated 144 healthy participants in a ratio of 1:1:1:1 to receive the low-(60 µg), middle-(120 µg), and high-dose (240 µg) vaccine or placebo at day 0, 3, 7 and 14. In phase 1b, 144 healthy participants were randomly allocated at a ratio of 1:1:1:1 to receive 0-3-7, 0/0-7, 0/0-3-7, 0/0-7-14 regimens to estimate the optimal strategy. The primary study endpoint was the incidence of solicited adverse events post-vaccination. The immunogenicity endpoints included the level of specific antibodies to five antigens after vaccination, as well as the cellular immune responses and functional antibodies. RESULTS: There were 31 (86%), 30 (83%), and 32 (89%) of 36 participants in the low-, middle-, and high-dose group reported solicited adverse events, respectively, most of the adverse events were mild or moderate. In phase 1b, the dose-adjusted rFSAV (90 µg) showed a better safety profile in the four immune procedures, and no vaccine-related serious adverse events were reported. The antigen-specific binding antibodies started to increase at day 7 and reached the peak around day 14 to 21. The cellular immune responses and functional antibodies also were substantially above background levels. CONCLUSIONS: rFSAV is safe, well tolerated in healthy adults, elicits rapid and robust specific humoral and cellular immune responses with unconventional immunization procedure in phase 1a and 1b. It deserves to be noted and further explored. CLINICAL TRIALS REGISTRATION: NCT02804711 and NCT03966040.

Evolution and spatial heterogeneity patterns of ecological efficiency of resource recycling in China.

Analyzing the evolution and heterogeneity patterns of resources' ecological efficiency in China could provide reference for balancing regional development and improving the ecological efficiency of resource recycling. With the panel data of resource recycling in 26 provinces (cities, regions), we measured the ecological efficiency during 2004 to 2017 by the super efficiency DEA model, and analyzed the evolution of ecological efficiency and heterogeneity patterns based on the regionalization. The results showed that, from 2004 to 2017, the ecological efficiency of resource recycling was increasing yearly, with a mean annual growth potential of 1.5%, showing an spatially increasing trend from inland to coast. The ecological efficiency in China showed significant spatial correlation, with clustering character among provinces. During 2004 to 2017, the overall correlation decreased yearly due to the strong radiation effect of high level provinces. Because of the decrease of differentiation in the north, northeast, east, central, south, southwest and northwest in China, the spatial heterogeneity of ecological efficiency of resource recycling in China turned to relieve, which was weakened by the increasing heterogeneity in the southwest region.

Safety and immunogenicity of a recombinant COVID-19 vaccine (Sf9 cells) in healthy population aged 18 years or older: two single-center, randomised, double-blind, placebo-controlled, phase 1 and phase 2 trials.

COVID-19 vaccines from multiple manufacturers are needed to cope with the problem of insufficient supply. We did two single-center, randomised, double-blind, placebo-controlled phase 1 and phase 2 trials to assess the safety, tolerability and immunogenicity of a recombinant COVID-19 vaccine (Sf9 cells) in healthy population aged 18 years or older in China. Eligible participants were enrolled, the ratio of candidate vaccine and placebo within each dose group was 3:1 (phase 1) or 5:1 (phase 2). From August 28, 2020, 168 participants were sequentially enrolled and randomly assigned to receive the low dose vaccine, high dose vaccine or placebo with the schedule of 0, 28 days or 0, 14, 28 days in phase 1 trial. From November 18, 2020, 960 participants were randomly assigned to receive the low dose vaccine, high dose vaccine or placebo with the schedule of 0, 21 days or 0, 14, 28 days in phase 2 trial. The most common solicited injection site adverse reaction within 7 days in both trials was pain. The most common solicited systematic adverse reactions within 7 days were fatigue, cough, sore throat, fever and headache. ELISA antibodies and neutralising antibodies increased at 14 days, and peaked at 28 days (phase 1) or 30 days (phase 2) after the last dose vaccination. The GMTs of neutralising antibody against live SARS-CoV-2 at 28 days or 30 days after the last dose vaccination were highest in the adult high dose group (0, 14, 28 days), with 102.9 (95% CI 61.9-171.2) and 102.6 (95% CI 75.2-140.1) in phase 1 and phase 2 trials, respectively. Specific T-cell response peaked at 14 days after the last dose vaccination in phase 1 trial. This vaccine is safe, and induced significant immune responses after three doses of vaccination.

Effects of Prior Influenza Exposure on Immunogenicity of Influenza Vaccine.

BACKGROUND: In this study, we investigated the effects of prior influenza exposure on vaccine-elicited humor immune responses to circulating influenza variants. METHOD: We randomly selected 360 participants in previous clinical trials stratified by age. Blood samples were collected and tested by hemagglutination-inhibition tests during the 2015-2016 influenza seasons in China. The antigenic map was plotted and antigenic distance was calculated. RESULTS: Subjects with H1-priming had higher cross-reactive antibodies titers against A/JiangsuTinghu/11019/2015(H3N2) compared with subjects with B-priming did (P adjusted = .038). Subjects with H1-priming also had higher cross-reactive antibodies titers against A/Jiangsu Qinhuai/11059/2015(H3N2) than subjects with both H1 and B priming (P adjusted = .036). Nevertheless, subjects with no H1 and B-priming had higher cross-reactive antibodies titers against A/Jiangsu Qinhuai/11059/2015(H3N2) than subjects with both H1 and B priming (P adjusted = .012). Antigenic distance was well matched with serological results. Moeover, age-specific differences in human postvaccination responses against the identical circulating strain was noted. In addition, children had the most cross-reactive response to both H3N2 and B-yamagata subtypes. CONCLUSIONS: Our results suggest that prior exposure to H1 or B influenza virus may influence cross-reactivity of H3-specific postvaccination responses and consequently could influence the vaccine effectiveness. Our findings also support that there are age-specific differences in human postvaccination responses.

Immunogenicity and safety of an inactivated quadrivalent influenza vaccine candidate versus inactivated trivalent influenza vaccines in participants >/=3 years of age: a double-blind, randomized, parallel-controlled phase III clinical trial in China.

BACKGROUND: Viruses from two antigenically distinct influenza B strains have co-circulated since the mid-1980s, yet inactivated trivalent influenza vaccines (TIVs) with either the Victoria or Yamagata lineage could only provide limited protection from influenza B strain. Quadrivalent influenza vaccine (QIV) including both influenza B lineages can improve protection against circulating influenza B viruses. METHODS: Participants >/ = 3 years of age were recruited, stratified by age, and then randomly allocated at a ratio of 2:1:1 to receive one-injection of the experimental QIV, TIV-Victoria (Vic) or TIV-Yamagata (Yam). The primary objective of this study was to demonstrate that the hemagglutination-inhibition (HI) antibodies induced by the QIV candidate are not inferior to the licensed TIVs. RESULTS: First, 3661 participants received the inoculation. The QIV was found to be non-inferior to TIVs in terms of the geometric mean titers (GMTs) and seroconversion rates (SCRs) of the HI antibodies against shared strains 28 days after completion of inoculation, and was superior to the TIVs against the alternate B strain, which is absent from the TIVs. The occurrences of adverse events (AEs) post-vaccination were similar across the treatment groups. CONCLUSION: The experimental QIV showed good immunogenicity and an acceptable safety profile.

Immunity duration of a recombinant adenovirus type-5 vector-based Ebola vaccine and a homologous prime-boost immunisation in healthy adults in China: final report of a randomised, double-blind, placebo-controlled, phase 1 trial.

BACKGROUND: The 2013-15 Ebola virus disease epidemic in west Africa greatly accelerated the development of Ebola vaccine. We aimed to analyse the immune persistence induced by one shot of an adenovirus type-5 vector-based Ebola virus vaccine up to 6 months and the effect of boosting with a homologous vector in healthy adults in China. METHODS: In a randomised, double-blind, placebo-controlled, phase 1 clinical trial in one site in Jiangsu Province, China, 120 healthy adults aged 18-60 years received an initial dose of intramuscular adenovirus type-5 Ebola virus vaccine of 4·0 × 1010 viral particles, 1·6 × 1011 viral particles, or placebo, and were followed up to day 168. Participants were subsequently re-recruited to receive a booster dose of the same vaccine or placebo, in the same dose, at month 6. Women who were pregnant, breastfeeding, or planned to become pregnant during the next month were excluded. Randomisation was conducted by computer-generated block randomisation. Randomisation data were unmasked for interim analysis of the data obtained between days 0-28 but not disclosed to participants or site staff. Safety and immunogenicity analysis were done on the intention-to-treat population. We aimed to assess the safety profile of the experimental vaccine and the immunity responses to a single-dose immunisation or a homologous prime-boost regimen. Primary outcomes were Ebola glycoprotein-specific ELISA antibody responses 28 days post-boost and the occurrences of adverse reactions post-boost. The original trial and the extended booster study were registered with ClinicalTrials.gov, numbers NCT02326194 and NCT02533791, respectively. FINDINGS: Between Dec 28, 2014, and Jan 9, 2015, we enrolled 210 volunteers. 90 participants were not randomised due to not meeting inclusion criteria (61), meeting exclusion criteria (4), or withdrawal of consent (25). 120 people were randomly assigned to receive intramuscular Ebola vaccine at 4·0 × 1010 viral particles (low dose, n=40), Ebola vaccine at 1·6 × 1011 viral particles (high dose, n=40), or placebo (n=40, in two groups of 20). After prime vaccination, the geometric mean titer (GMT) of ELISA EC90 peaked at 682·7 (95% CI 424·3-1098·5) in the low-dose vaccine group and 1305·7 (970·1-1757·2) in the high-dose vaccine group at day 28, and then fell gradually through the next a few months to 575·5 (394·8-838·8) in the high-dose vaccine group and 197·9 (107·9-362·7) in the low-dose vaccine group at day 168. No specific response was recorded in the placebo group with a GMT of 5·0. Of the 120 participants involved in the initial trial, ten participants declined to participate, and 110 were included in the boost immunisation: 38 received the low dose, 35 received the high dose, and 37 received the placebo. At day 28 after boost vaccination, the ELISA EC90 titres rapidly rose to 6110 (95% CI 4705-7935) in the low-dose group and to 11825 (8904-15705) in the high dose group. 78 of 110 participants reported at least one solicited adverse reaction within the first 7 days after booster administration. Both of the groups who received vaccine showed significantly higher incidence of mild or moderate solicited adverse reactions than did the placebo group. INTERPRETATION: The adenovirus 5-vectored Ebola vaccine of 1·6 × 1011 viral particles was highly immunogenic and safe. The lower dose of 4·0 × 1010 viral particles was also safe, but immunogenicity seemed to be more vulnerable to the pre-existing immunity of adenovirus 5. A homologous priming-boosting regimen with adenovirus type-5 Ebola vaccine at 6 months interval was able to elicit greater antibody responses with longer duration. These results support an immunisation strategy to implement a booster injection for a more durable protection against Ebola virus disease. FUNDING: Chinese Ministry of Science and Technology and The National Health and Family Planning Commission, Beijing Institute of Biotechnology, and Tianjin CanSino Biotechnology.

How to understand the efficacy measurements for enterovirus type 71 vaccine?

The choice of endpoint was most important for an efficacy vaccine trial. The objective of this paper is to gear toward answering questions about the rationality and scientificity of the primary endpoints choosing, case capturing and diagnosis strategy in our recently reported EV71 vaccine efficacy phase 3 trial. In order to obtain both high sensitivity and specificity in the case detecting, EV71-associated disease had been chosen as primary endpoint, a broad spectrum of clinical symptoms was surveyed, both the real-time RT-PCR and virus isolation were combined for the laboratory diagnosis, and serial specimens since disease onset were collected for assays. Though, the EV71 vaccine efficacy was well measured in the phase 3 trial, several potential factors could also have influences on the cases confirming. More evidence of EV71 vaccine efficacy will be demanded in post-marketing studies in the future.

Clinical evaluation for batch consistency of an inactivated enterovirus 71 vaccine in a large-scale phase 3 clinical trial.

The demonstration of batch-to-batch consistency to confirm the reliability of the manufacturing process has become a mandatory step in vaccine development. This is a post-hoc analysis aimed to provide more solid evidence on the immunogenicity and consistency of 3 consecutive batches of a novel inactivated enterovirus 71 (EV71) vaccine. In total 10 245 healthy Chinese children aged 6-35 months had been recruited and randomized to receive one of 3 batches of EV71 vaccine or placebo according to a two-dose immunization schedule in a phase 3 clinical trial. Blood samples were taken just before and 28 days after vaccinations for serological tests of EV71 neutralizing antibody (NTAb) titer from the subjects. Among them, 7263 (70.9%) subjects with seronegative EV71 NTAb at baseline and the data of serological tests post-vaccination available were included for the analysis. The results showed that EV71 vaccine elicited high geometric mean titers (GMTs) of 407.0 U/mL (95% CI, 373.5-443.6) for batch 1, 468.1 U/mL (95% CI, 432.2-507.0) for batch 2, and 520.6 U/mL (95% CI, 481.2-563.3) for batch 3. The two-sided 95% confidence intervals (CIs) for the GMT ratios between each pair of vaccine batches were all within an interval of [0.67, 1.5]. Subjects who received EV71 vaccines demonstrated significant higher GMTs than those received placebos did (P<0.001). In terms of incidence of both local and general adverse reactions, no differences were found among 3 vaccine batches and placebos. EV71 vaccine was highly immunogenic in children, and the 3 consecutive batches were well consistent.

Tolerability and immunogenicity of an inactivated enterovirus 71 vaccine in Chinese healthy adults and children: an open label, phase 1 clinical trial.

In this open labeled phase 1 clinical trial with enterovirus 71 (EV71) vaccine (ClinicalTrials.gov number: NCT01267903) performed in Donghai County, Jiangsu Province, China, in January 2011. A total of 100 healthy participants, stratified by age (40 adults aged 16-22 y and 60 children aged 6-15 y), were enrolled from volunteers and sequentially received EV71 vaccines of 160U (only for children), 320U, or 640U on day 0 and 28, in a manner of dose escalation. All the participants were followed for 28 d after each shot. During the study period, 37 participants reported at least one injection-site or systemic adverse reaction. No case of grade 3 adverse reaction or serious adverse event (SAE) was observed. Also no dose-related increase in reaction rate was noticed. Pain at injection-site and fever were the most frequently reported local and systematic reaction, respectively. The studied EV71 vaccines demonstrated acceptable tolerability and no anti-nuclear antibody (ANA) seropositive was detected pre or post vaccinations in participants. Also, no clinically significant abnormal change for the liver or kidney function indexes was found. In the according-to-protocol cohort for immunogenicity, it was observed one dose of EV71 vaccine elicited good immune response in the participants, especially for the ones with sero-positive baseline. No obvious dose-response relationship for immunogenicity was found.

Retrospective study of the incidence of HFMD and seroepidemiology of antibodies against EV71 and CoxA16 in prenatal women and their infants.

BACKGROUND: Hand, foot, and mouth disease (HFMD) has been emerging as an important public problem over the past few decades, especially in Asian and Pacific regions. A national program on EV71 vaccine development against HFMD was initiated in China, in 2008, which called for a need for seroepidemiological study for the target population. METHODOLOGY/PRINCIPAL FINDINGS: This was a retrospective study conducted in Jiangsu Province, in October, 2010. We measured the neutralizing antibodies against EV71 and CoxA16 in a cohort of infants aged of 2, 7, 12, and 27-38 months and their mothers just before delivery. Series sera samples from 975 infants and 555 mothers were collected and analyzed. Questionnaires on the history of HFMD were completed in the survey. A total of 143 HFMD cases were collected, but only 11.2% were reported to the National Infectious Disease Information Management System. The level of maternal antibody titers decreased dramatically during the first 7 month and remained at a relatively low level thereafter. But it increased significantly from month 12 to months 27-38. The accumulate incidence density of HFMD demonstrated a significant increase after 14 months of age, resulting in a accumulate incidence density of 50.8/1000 person-years in survey period. Seropositivity of EV71 antibody in infants at the age of 2 months seems to demonstrate a protective effect against HFMD. CONCLUSIONS AND SIGNIFICANCE: High seropositive rate of EV71 and CoxA16 antibody was found in prenatal women in mainland China, and there is a need to enhance the HFMD case management and the current surveillance system. We suggest that infants aged between 6 to 14 months should have the first priority to receive EV71 vaccine.

Reactogenicity and immunogenicity of an enterovirus 71 vaccine in Chinese healthy children and infants.

BACKGROUND: Enterovirus 71 (EV71) is highly contagious and can cause severe complications. A safe and effective vaccine is needed. We assessed the reactogenicity and immunogenicity of an inactivated, alum-adjuvanted EV71 vaccine in this study. METHODS: A randomized, double-blind, placebo-controlled clinical trial was undertaken in 360 healthy participants who were stratified into 2 age groups (6-12 and 13-60 months), and randomly allocated to receive placebo or the investigational vaccine containing 160 U, 320 U or 640 U antigen per dose by the ratio of 1:1:1:1 at days 0 and 28. Reactogenic data within 28 days after each vaccination were recorded. Blood samples were obtained on days 0, 28 and 56 for neutralizing antibody assay. RESULTS: Overall, 193 participants reported at least 1 injection-site or systemic adverse reaction with 53.3% and 54.4% participants receiving the study vaccine and placebo, respectively. Most of the reactions were mild or moderate. Three serious adverse events were observed, but none was related to vaccination. In the participants with seronegative baseline, after 2 doses all the participants receiving EV71 vaccines were seropositive and the seroconversion rates were more than 98.1%. In the participants with seropositive baseline, 1 dose induced good seroconversion rates of more than 64.3% in participants receiving EV71 vaccines. CONCLUSIONS: This study found that the inactivated EV71 vaccine was well tolerated and had good immunogenicity in healthy children and infants. A single dose induced typical booster response in the participants with a seropositive baseline, and 2 doses were needed for the immunologically naive participants.

[Safety and immunogenicity of rabies vaccine (chick embryo cell) for human use produced in Germany and India].

OBJECTIVE: To evaluate the safety and immunogenicity of Rabipur produced in India. METHODS: A random and single-blind study was conducted to compare the safety, effect and sero conversion rates. Rabipur produced in Germany used as control group. RESULTS: The results showed that they were no severe systemic and local reaction occurred in trial group (Rabipur produced in India). The difference between trial group and control group was not significant. 14 day and 45 days after the first dose, the seroconversion rates of the two groups were 100%. 14 day and 45 days after the first dose, GMC of the two groups increased obviously and highly beyond 0.5TU/ml. CONCLUSION: Rabipur produced in India has excellent safety and immunogenicity. Trial Registration National Food Drugs Surveillance Administrative Bureau, "Medicine Clinical Experiment Written directive from a superior" 2005L04184.