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A significant correlation has been shown between the binding antibody responses against original severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and vaccine efficacy of 4 approved coronavirus disease 2019 vaccines. We therefore assessed the immune response against original SARS-CoV-2 elicited by the adjuvanted S-Trimer vaccine, SCB-2019 + CpG/alum, in the same assay and laboratory. Responses to SCB-2019 were comparable or superior for antibody to original and Alpha variant when compared with 4 approved vaccines. The comparison accurately predicted success of the recently reported efficacy trial of SCB-2019 vaccine. Immunogenicity comparisons to original strain and variants of concern should be considered as a basis for authorization of vaccines., The antibody-binding responses to the adjuvanted S-Trimer vaccine, SCB-2019 + CpG/alum, were compared with approved vaccines and accurately predicted success of the recently reported efficacy trial of SCB-2019 vaccine. Immunogenicity comparisons should be considered as a basis for authorization of vaccines.

Background We report 2-year persistence of immune response to Takeda's prophylactic purified formalin-inactivated whole Zika virus vaccine candidate (TAK-426) compared with that observed after natural infection. Methods A randomized, observer-blind, placebo-controlled, dose-selection, phase 1 trial was conducted in 18–49-year-old adults at 9 centers (7 in the United States, 2 in Puerto Rico) from 13 November 2017 to 24 November 2020. Primary objectives were safety, tolerability, and immunogenicity of 3 increasing doses of TAK-426 administered as 2 doses 28 days apart to flavivirus (FV)–naive and FV-primed adults. Here, we report on safety and persistence of immunity up to 2 years after primary vaccination with 10-μg TAK-426, the highest dose, and compare neutralizing antibody responses with those observed after natural infection. Results TAK-426 at 10-μg had an acceptable safety profile in FV-naive and FV-primed adults up to 24 months after dose 2. Seropositivity for neutralizing antibodies was 100% at 1 year, and 93.8% and 76.2% at 2 years in FV-naive and FV-primed groups, respectively. TAK-426 responses were comparable in magnitude and kinetics with those elicited by natural Zika virus infection. Conclusions These results support the further clinical development of TAK-426 for both FV-naive and FV-primed populations. Clinical Trials Registration NCT03343626

Highlights • A novel IPV vaccine was developed from attenuated Sabin poliovirus strains. • The vaccine was generally well tolerated in adults, toddlers and infants. • The vaccine was immunogenic as a booster in previously polio-vaccinated toddlers. • The vaccine was insufficiently immunogenic from 6 weeks of age in the EPI schedule. • There was evidence of interference of the immune response by maternal antibodies., Background To increase the global supply of affordable IPV vaccine, preferably using Sabin viruses to comply with GAPIII requirements, Takeda has assessed three dosages of a stand-alone sIPV. Methods In this phase I/II study two cohorts of 40 adults and 60 toddlers, respectively, were initially assessed for safety after receiving high-dosage sIPV compared with placebo (adults) or Salk IPV (toddlers). A cohort of 240 infants was then enrolled and randomized (1:1:1:1) to receive low-, medium- or high-dosage sIPV, or a reference Salk IPV in a three-dose primary schedule at 6, 10 and 14 weeks of age. Parents completed safety diaries for 4 weeks after each dose, and immunogenicity was measured as neutralization antibody titers at baseline and four weeks after vaccination. Results All vaccinations were generally well-tolerated and sIPV had a comparable safety profile to the control arm in adults or the reference Salk IPV vaccine in toddlers and infants. Infants displayed dosage-dependent immune responses to sIPV when assayed using Sabin strains, which were equivalent to the reference IPV in the high-dosage sIPV group for serotypes 1 and 2, but not for Sabin and Salk serotype 3. Seroconversion rates (SCR) of the low- and medium-dosage groups were significantly lower than the Salk IPV group for both Sabin and Salk serotypes 1 and type 2 (p

We previously reported the efficacy of the adjuvanted-protein COVID-19 vaccine candidate S-Trimer (SCB-2019) in adults who showed no evidence of previous exposure to SARS-CoV-2. In this study, we aimed to investigate the extent of protection afforded by previous exposure to SARS-CoV-2 on subsequent COVID-19 infection, as well as the efficacy, safety, and reactogenicity of SCB-2019 in participants who were enrolled in the Study evaluating Protective-Efficacy and safety of Clover's Trimeric Recombinant protein-based and Adjuvanted COVID-19 vaccine (SPECTRA) trial who had already been exposed to SARS-CoV-2 before vaccination.In a phase 2 and 3 multicentre, double-blind, randomised, placebo-controlled trial (SPECTRA) done at 31 sites in five countries, participants were randomly assigned 1:1 using the Cenduit Interactive Response Technology system (IQVIA, Durham, NC, USA), with a block size of six, to receive two doses of either SCB-2019 or placebo 21 days apart. The primary outcomes of the SPECTRA trial were vaccine efficacy, measured by real-time PCR (rtPCR)-confirmed COVID-19 of any severity, with onset from 14 days after the second vaccine dose, as well as the safety and solicited local and systemic adverse events in the phase 2 subset. Here, we present secondary analyses to calculate the protective efficacy due to previous exposure to SARS-CoV-2 against reinfection with COVID-19 according to severity in SPECTRA participants who had evidence of exposure to SARS-CoV-2 at baseline, including efficacy against identified viral variants, as well as efficacy of SCB-2019 vaccination in this population.We enrolled 30 174 participants between March 24, 2021, and Aug 10, 2021. In the 14 670 participants who were randomly assigned to receive placebo, there were 418 (2·8%) confirmed cases of COVID-19; 65 (0·9%) of 7339 SARS-CoV-2-exposed participants, and 353 (4·8%) of 7331 SARS-CoV-2-naive participants (attack rates of 5·5 cases per 100 person-years for SARS-CoV-2-exposed participants and 32·4 cases per 100 person-years for SARS-CoV-2-naive participants). Protective efficacy due to previous exposure to SARS-CoV-2 was 83·2% (95% CI 78·0-87·3) against any COVID-19, 92·5% (82·9-97·3) against moderate-to-severe COVID-19, and 100% (59·3-100) against severe COVID-19; no SARS-CoV-2-exposed participants had hospitalisation associated with COVID-19. Protective efficacy against variants were 100% for alpha (B.1.1.7) and lambda (C.37) variants, 88·6% (14·9-99·7) for B.1.623, 93·6% (80·1-98·7) for gamma (P.1), and 92·4% (81·2-97·6) for mu (B.1.621) variants, and lowest against beta (B.1.351; 72·2% [33·1-89·9]) and delta (B.1.617.2; 77·2% [61·3-87·2]) variants. In addition, one dose of SCB-2019 had 49·9% (1·5-75·6) efficacy against any symptomatic COVID-19, and two doses had 64·2% (26·5-83·8) efficacy. SCB-2019 was well tolerated in SARS-CoV-2-exposed participants, but was associated with higher rates of injection site pain (89 [33·8%] of 263 participants) than placebo (16 [6·7%] of 239 participants). Rates of solicited systemic adverse events, severe adverse events, and serious adverse events were similar between vaccine and placebo groups, and with rates in SARS-CoV-2-naive vaccine recipients.Previous exposure to SARS-CoV-2 decreased the risk and severity of subsequent COVID-19 infection, even against newly emerging variants. Protection is further enhanced by one or two doses of SCB-2019.Clover Biopharmaceuticals, The Coalition for Epidemic Preparedness Innovations (CEPI).

A range of safe and effective vaccines against SARS CoV 2 are needed to address the COVID 19 pandemic. We aimed to assess the safety and efficacy of the COVID-19 vaccine SCB-2019.This ongoing phase 2 and 3 double-blind, placebo-controlled trial was done in adults aged 18 years and older who were in good health or with a stable chronic health condition, at 31 sites in five countries (Belgium, Brazil, Colombia, Philippines, and South Africa). The participants were randomly assigned 1:1 using a centralised internet randomisation system to receive two 0·5 mL intramuscular doses of SCB-2019 (30 μg, adjuvanted with 1·50 mg CpG-1018 and 0·75 mg alum) or placebo (0·9% sodium chloride for injection supplied in 10 mL ampoules) 21 days apart. All study staff and participants were masked, but vaccine administrators were not. Primary endpoints were vaccine efficacy, measured by RT-PCR-confirmed COVID-19 of any severity with onset from 14 days after the second dose in baseline SARS-CoV-2 seronegative participants (the per-protocol population), and the safety and solicited local and systemic adverse events in the phase 2 subset. This study is registered on EudraCT (2020-004272-17) and ClinicalTrials.gov (NCT04672395).30 174 participants were enrolled from March 24, 2021, until the cutoff date of Aug 10, 2021, of whom 30 128 received their first assigned vaccine (n=15 064) or a placebo injection (n=15 064). The per-protocol population consisted of 12 355 baseline SARS-CoV-2-naive participants (6251 vaccinees and 6104 placebo recipients). Most exclusions (13 389 [44·4%]) were because of seropositivity at baseline. There were 207 confirmed per-protocol cases of COVID-19 at 14 days after the second dose, 52 vaccinees versus 155 placebo recipients, and an overall vaccine efficacy against any severity COVID-19 of 67·2% (95·72% CI 54·3-76·8), 83·7% (97·86% CI 55·9-95·4) against moderate-to-severe COVID-19, and 100% (97·86% CI 25·3-100·0) against severe COVID-19. All COVID-19 cases were due to virus variants; vaccine efficacy against any severity COVID-19 due to the three predominant variants was 78·7% (95% CI 57·3-90·4) for delta, 91·8% (44·9-99·8) for gamma, and 58·6% (13·3-81·5) for mu. No safety issues emerged in the follow-up period for the efficacy analysis (median of 82 days [IQR 63-103]). The vaccine elicited higher rates of mainly mild-to-moderate injection site pain than the placebo after the first (35·7% [287 of 803] vs 10·3% [81 of 786]) and second (26·9% [189 of 702] vs 7·4% [52 of 699]) doses, but the rates of other solicited local and systemic adverse events were similar between the groups.Two doses of SCB-2019 vaccine plus CpG and alum provides notable protection against the entire severity spectrum of COVID-19 caused by circulating SAR-CoV-2 viruses, including the predominating delta variant.Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations.

A significant correlation has been shown between the binding antibody responses against original SARS-CoV-2-S-protein all performed in one laboratory and vaccine efficacy of four approved COVID-19 vaccines. We therefore assessed the immune response against original SARS-CoV-2 elicited by the adjuvanted S-Trimer vaccine, SCB-2019 + CpG/alum, in the same assay and laboratory. When compared with four approved vaccines immune responses to SCB-2019 predicted 81% − 94% efficacy against the original strain and 75–94% against the Alpha variant (B.1.1.7). Immunogenicity comparisons to original strain and variants of concern (VOC) should be considered as a basis for authorization of vaccines because efficacy studies now have predominantly VOC cases.

Background We have previously reported the safety and immunogenicity 4 weeks after 2 doses of the Clover coronavirus disease 2019 (COVID-19) vaccine candidate, SCB-2019, a stabilized prefusion form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S-trimer). We now report persistence of antibodies up to 6 months after vaccination, and cross-neutralization titers against 3 variants of concern (VoCs). Methods In a phase 1 study, adult (18–54 years of age) and elderly (55–75 years of age) volunteers received 2 vaccinations 21 days apart with placebo or 3-, 9-, or 30-µg. We measured immunoglobulin G (IgG) antibodies against SCB-2019, angiotensin-converting enzyme 2 (ACE2) competitive binding antibodies, and neutralizing antibodies against wild-type SARS-CoV-2 (Wuhan-Hu-1) at days 101 and 184, and neutralizing antibodies against 3 VoCs, Alpha (B.1.1.7), Beta (B.1.351), and Gamma (P.1), in day 36 sera. Results Titers waned from their peak at days 36–50, but SCB-2019 IgG antibodies, ACE2 competitive binding antibodies, and neutralizing antibodies against wild-type SARS-CoV-2 persisted at 25%–35% of their observed peak levels at day 184. Day 36 sera also demonstrated dose-dependent increases in neutralizing titers against the 3 VoCs. Conclusions SCB-2019 dose-dependently induced immune responses against wild-type SARS-CoV-2, which persisted up to day 184. Neutralizing antibodies were cross-reactive against 3 of the most prevalent VoCs., Immune responses to the SCB-2019 COVID-19 vaccine adjuvanted with CpG-1018/alum had waned but were still measurable 180 days after the first vaccination. Early responses showed some cross-protection against variants of concern.

Summary Background As part of the accelerated development of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we report a dose-finding and adjuvant justification study of SCB-2019, a protein subunit vaccine candidate containing a stabilised trimeric form of the spike (S)-protein (S-Trimer) combined with two different adjuvants. Methods Our study is a phase 1, randomised, double-blind placebo-controlled trial at a specialised clinical trials centre in Australia. We enrolled healthy adult volunteers in two age groups: younger adults (aged 18–54 years) and older adults (aged 55–75 years). Participants were randomly allocated either vaccine or placebo using a list prepared by the study funder. Participants were to receive two doses of SCB-2019 (either 3 μg, 9 μg, or 30 μg) or a placebo (0·9% NaCl) 21 days apart. SCB-2019 either had no adjuvant (S-Trimer protein alone) or was adjuvanted with AS03 or CpG/Alum. The assigned treatment was administered in opaque syringes to maintain masking of assignments. Reactogenicity was assessed for 7 days after each vaccination. Humoral responses were measured as SCB-2019 binding IgG antibodies and ACE2-competitive blocking IgG antibodies by ELISA and as neutralising antibodies by wild-type SARS-CoV-2 microneutralisation assay. Cellular responses to pooled S-protein peptides were measured by flow-cytometric intracellular cytokine staining. This trial is registered with ClinicalTrials.gov, NCT04405908; this is an interim analysis and the study is continuing. Findings Between June 19 and Sept 23, 2020, 151 volunteers were enrolled; three people withdrew, two for personal reasons and one with an unrelated serious adverse event (pituitary adenoma). 148 participants had at least 4 weeks of follow-up after dose two and were included in this analysis (database lock, Oct 23, 2020). Vaccination was well tolerated, with two grade 3 solicited adverse events (pain in 9 μg AS03-adjuvanted and 9 μg CpG/Alum-adjuvanted groups). Most local adverse events were mild injection-site pain, and local events were more frequent with SCB-2019 formulations containing AS03 adjuvant (44–69%) than with those containing CpG/Alum adjuvant (6–44%) or no adjuvant (3–13%). Systemic adverse events were more frequent in younger adults (38%) than in older adults (17%) after the first dose but increased to similar levels in both age groups after the second dose (30% in older and 34% in younger adults). SCB-2019 with no adjuvant elicited minimal immune responses (three seroconversions by day 50), but SCB-2019 with fixed doses of either AS03 or CpG/Alum adjuvants induced high titres and seroconversion rates of binding and neutralising antibodies in both younger and older adults (anti-SCB-2019 IgG antibody geometric mean titres at day 36 were 1567–4452 with AS03 and 174–2440 with CpG/Alum). Titres in all AS03 dose groups and the CpG/Alum 30 μg group were higher than were those recorded in a panel of convalescent serum samples from patients with COVID-19. Both adjuvanted SCB-2019 formulations elicited T-helper-1-biased CD4+ T-cell responses. Interpretation The SCB-2019 vaccine, comprising S-Trimer protein formulated with either AS03 or CpG/Alum adjuvants, elicited robust humoral and cellular immune responses against SARS-CoV-2, with high viral neutralising activity. Both adjuvanted vaccine formulations were well tolerated and are suitable for further clinical development. Funding Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations.

BackgroundAs part of the accelerated development of prophylactic vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) we report a first-in-human dose-finding and adjuvant justification study of SCB-2019, a novel protein subunit vaccine candidate composed of a stabilised trimeric form of the spike (S)-protein produced in CHO-cells, combined with two different adjuvants.MethodsThis phase 1 study was done in one centre in Western Australia in 151 healthy adult volunteers in two age groups (18–54 and 55–75 years), allocated to 15 groups (nine young and six older adults) to receive two doses, 21 days apart, of placebo, or 3 μg, 9 μg or 30 μg SCB-2019, alone or adjuvanted with AS03 or CpG/Alum. Reactogenicity was assessed for 7 days after each vaccination. Humoral responses were measured as SCB-2019 binding and ACE2-competitive binding IgG antibodies by ELISA, and as neutralising antibodies by wild-type SARS-CoV-2 microneutralisation assay; cellular responses to pooled S-protein peptides were measured by flow-cytometric intracellular cytokine staining.FindingsWe report on 148 participants with at least 4 weeks follow-up post dose 2. Three participants withdrew, two for personal reasons and one with an unrelated SAE (pituitary adenoma). Vaccination was well tolerated, with few Grade 3 solicited adverse events (AE). Most local AEs were mild injection site pain, which were more frequent with formulations containing AS03 than CpG/Alum or unadjuvanted SCB-2019. Systemic AEs, mostly transient headache, fatigue or myalgia, were more frequent in young adults than older adults after the first dose, but similar after second doses. Unadjuvanted SCB-2019 elicited minimal immune responses, but SCB-2019 with fixed doses of AS03 or CpG/Alum induced high titres and seroconversion rates of binding and neutralising antibodies in both young and older adults. Titres were higher than those observed in a panel of COVID-19 convalescent sera in all AS03 groups and high dose CpG/Alum groups. Both adjuvanted formulations elicited Th1-biased CD4+ T cell responses.InterpretationSCB-2019 trimeric protein formulated with AS03 or CpG/Alum adjuvants elicited robust humoral and cellular immune responses against SARS-CoV-2 with high viral neutralising activity. Both adjuvanted formulations were well tolerated and are suitable for further clinical development.Clinical trial registrationClinicalTrials.gov identifier NCT04405908.

Summary Background Zika virus, a flavivirus transmitted by Aedes aegypti and Aedes albopictus mosquitoes, is associated with cases of congenital malformations and neurological complications. Absence of specific treatment makes a prophylactic Zika virus vaccine an unmet medical need. We assessed safety and immunogenicity of three doses of a purified, inactivated, Zika virus vaccine candidate in healthy flavivirus-naive and flavivirus-primed adults. Methods This two-part, multicentre, observer-blind, randomised, placebo-controlled, phase 1 trial was done at seven medical clinics in the USA and two in Puerto Rico. Eligible participants were healthy adults aged 18–49 years. Participants were randomly assigned (1:1:1:1), using a sponsor-supplied randomisation scheme, to four groups to receive two intramuscular injections, 28 days apart, of saline placebo or TAK-426 containing 2 μg, 5 μg, or 10 μg antigen. Participants, investigators, and vaccine administrating personnel were masked to group assignment. Part 1 of the study assessed flavivirus-naive participants and part 2 assessed flavivirus-primed participants. The primary outcomes were safety, tolerability, and immunogenicity based on solicited local reactions and solicited systemic adverse events in the 7 days after each dose; unsolicited adverse events and serious adverse events in the 28 days after each dose; and geometric mean titres (GMTs) of neutralising anti-Zika virus antibodies at 28 days after the second dose. Safety assessments were done in all participants who received at least one dose of vaccine. Immunogenicity assessments were in the per-protocol set, comprising all participants who received at least one dose of vaccine and provided valid serology results at baseline and at least one post-vaccination timepoint, with no major protocol violations. The trial is ongoing and is registered at ClinicalTrials.gov ( NCT03343626 ). Findings Between Nov 13, 2017, and Oct 24, 2018, 894 volunteers were screened and 271 enrolled (125 flavivirus-naive and 146 flavivirus-primed participants). All TAK-426 doses were well tolerated with no deaths, no vaccine-related serious adverse events, and similar rates of mainly mild to moderate adverse events. TAK-426 elicited dose-dependent increases in antibody GMTs in both flavivirus-naive and flavivirus-primed participants. 28 days after dose 2, plaque-reduction neutralisation test GMTs in flavivirus-naive participants were 1130 (95% CI 749–1703) in the 2 μg TAK-426 group, 1992 (1401–2833) in the 5 μg TAK-426 group, and 3690 (2677–5086) in the 10 μg TAK-426 group. In pairwise comparisons, responses after two vaccinations in the 10 μg group were significantly greater than in the 2 μg group (GMT ratio 3·27 [95% CI 1·98–5·39], p Interpretation TAK-426 was well tolerated, with an acceptable safety profile, and was immunogenic in both flavivirus-naive and flavivirus-primed adults. Based on the safety and immunogenicity profiles of all TAK-426 doses assessed, the 10 μg TAK-426 dose was selected for further clinical development. Funding Takeda Vaccines and the US Biomedical Advanced Research and Development Authority. Translation For the Spanish translation of the abstract see Supplementary Materials section.

We conducted 3 phase III, randomized, open-label, clinical trials assessing the safety, reactogenicity (all studies), immunogenicity (Primary vaccination study) and persistence of immune responses (Booster study) to the combined diphtheria, tetanus, pertussis, poliomyelitis, and Haemophilus influenzae type b vaccine (DTPa-IPV/Hib) in Chinese infants and toddlers. In the Pilot study (NCT00964028), 50 infants (randomized 1:1) received 3 doses of DTPa-IPV/Hib at 2–3–4 (Group A) or 3–4–5 months of age (Group B). In the Primary study (NCT01086423), 984 healthy infants (randomized 1:1:1) received 3 doses of DTPa-IPV/Hib at 2–3–4 (Group A) or 3–4–5 (Group B) months of age, or concomitant DTPa/Hib and poliomyelitis (IPV) vaccination at 2–3–4 months of age (Control group); 825 infants received a booster dose of DTPa/Hib and IPV at 18–24 months of age (Booster study; NCT01449812). In the Pilot study, unsolicited symptoms were more frequent in Group A (16 versus 1 infant; mostly upper respiratory tract infection and pyrexia); this observation was attributed to an epidemic outbreak of viral infections. Non-inferiority of 3-dose primary vaccination with DTPa-IPV/Hib over separately administered DTPa/Hib and IPV was demonstrated for Group A (primary objective). Similar antibody concentrations were observed in all groups, except for anti-polyribosyl-ribitol phosphate and anti-poliovirus types 1–3 which were higher in DTPa-IPV/Hib recipients. Protective antibody levels against all vaccine antigens remained high until booster vaccination. Three-dose vaccination with DTPa-IPV/Hib had a clinically acceptable safety profile.

Multivalent combination vaccines have reduced the number of injections and therefore improved vaccine acceptance, timeliness of administration and global coverage. The hexavalent diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus/Haemophilus influenzae type b (DTPa-HBV-IPV/Hib; Infanrix hexa™) vaccine, administered according to various schedules, is widely used for the primary vaccination of infants worldwide. In the current publication, we are presenting the immunogenicity and safety of 3 doses of DTPa-HBV-IPV/Hib vaccine when administered to Indian infants. 224 healthy infants (mean age 6.8 weeks) were vaccinated at 6–10–14 weeks (W) of age (n = 112) or 2–4–6 months (M) of age (n = 112). One month after the third vaccine dose, the seroprotection/seropositivity status against diphtheria, pertussis, tetanus, polio, hepatitis B and Hib antigens ranged from 98.6% to 100% in both groups. The vaccine response rate to the pertussis antigens ranged from 97% to 100%. Pain (6–10–14W group: 25.2%; 2–4–6M group: 13.4%) and fever (15.3% and; 15.2%, respectively) were the most frequently reported solicited local and general symptoms. Unsolicited adverse events were reported for 35.7% (6–10–14W group) and 22.3% (2–4–6M group) of subjects. No vaccine related serious adverse events were reported. In conclusion, the hexavalent DTPa-HBV-IPV/Hib vaccine was immunogenic and well tolerated, irrespective of the dosing schedule.

Despite effective infant immunization against pertussis, the disease continues to circulate due to waning immunity. Booster vaccinations against pertussis beyond infancy are widely recommended. In Vietnam, however, no recommendations for pertussis boosters beyond the second year of life exist. This open-label, single-centre study was designed to assess the safety of a single booster dose of reduced-antigen-content-diphtheria-tetanus-acellular-pertussis vaccine (dTpa) in 300 healthy Vietnamese children (mean age 7.9years), who had completed primary vaccination against diphtheria, tetanus and pertussis. Solicited symptoms were recorded for 4days and unsolicited and serious adverse events (SAEs) for 31days post-vaccination. Pain and fatigue were the most common solicited local and general symptoms in 35.0% and 14.0% of children, respectively. Grade 3 swelling occurred in 3 children; no large injection site reactions or SAEs were reported. The dTpa booster vaccine was well tolerated and this study supports its administration in school age Vietnamese children.

Introduction: This was the first study conducted to evaluate the efficacy of 2 oral doses of the human rotavirus vaccine, RIX4414 in Singaporean infants during the first 3 years of life. Materials and Methods: Healthy infants, 11 to 17 weeks of age were enrolled in this randomised (1:1), double-blinded, placebo-controlled study to receive 2 oral doses of RIX4414 vaccine/placebo following a 0-, 1-month schedule. Vaccine efficacy against severe rotavirus (RV) gastroenteritis (Vesikari score ≥11) caused by wild-type RV strains from a period starting from 2 weeks post-Dose 2 until 2 and 3 years of age was calculated with 95% confidence interval (CI). Immunogenicity and safety of the vaccine were also assessed. Results: Of 6542 infants enrolled, 6466 were included in the efficacy analysis and a subset of 100 infants was included in the immunogenicity analysis. Fewer severe RV gastroenteritis episodes were reported in the RIX4414 group when compared to placebo at both 2 and 3 year follow-up periods. Vaccine efficacy against severe RV gastroenteritis at the respective time points were 93.8% (95% CI, 59.9 to 99.9) and 95.2% (95% CI, 70.5 to 99.9). One to 2 months post-Dose 2 of RIX4414, 97.5% (95% CI, 86.8 to 99.9) of infants seroconverted for anti-RV IgA antibodies. The number of serious adverse events recorded from Dose 1 until 3 years of age was similar in both groups. Conclusion: Two oral doses of RIX4414 vaccine was immunogenic and provided high level of protection against severe RV gastroenteritis in Singaporean children, during the first 3 years of life when the disease burden is highest. Key words: Diarrhoea, G and P types, Gastroenteritis, Intussusception

This study evaluated the immunogenicity of the human rotavirus (RV) vaccine (RIX4414) when co-administered with routine childhood vaccines in Chinese infants (NCT01171963). Healthy infants aged 6–16 weeks received 2 doses of either RIX4414 or placebo according to a 0, 1-month schedule. Infants received routine diphtheria-tetanus-acellular pertussis (DTPa) and oral poliovirus (OPV) vaccines either separately from or concomitantly with RIX4414/placebo (separate and co-administration cohorts, respectively). Anti-RV IgA seroconversion rates (one month post-dose-2) and seropositivity rates (at one year of age) were measured using ELISA. Immune responses against the DTPa and OPV antigens were measured one month post-DTPa dose-3 in the co-administration cohort. Solicited local and general symptoms were recorded for 8-days post-vaccination (total cohort). The according-to-protocol immunogenicity population included 511 infants in the separate cohort and 275 in the co-administration cohort. One month post-RIX4414 dose-2, anti-RV IgA seroconversion rates were 74.7% (95% confidence interval [CI]: 68.9–79.9) and 64.2% (95% CI: 55.4–72.3) in the separate and co-administration cohorts; seropositivity rates at one year of age were 71.5% (95% CI: 65.5–77.1) and 50.0% (95% CI: 40.9–59.1), respectively. One month post-DTPa dose-3, all infants in the co-administration cohort were seroprotected against diphtheria and tetanus, and seropositive for pertussis toxoid, pertactin and filamentous haemaglutinin. Two months post-OPV dose-3, seroprotection rates against anti-poliovirus types 1, 2 and 3 were >99% in the co-administration cohort. Reactogenicity profiles were similar in both cohorts. RIX4414 was immunogenic and well-tolerated in Chinese infants and did not appear to interfere with the immunogenicity and reactogenicity of co-administered routine childhood vaccines.

BACKGROUND: Regular booster vaccination might be necessary throughout life to protect against pertussis infection. Nevertheless the duration of protection after booster vaccination remains unclear. In this study, antibody persistence up to 10 years after previous vaccination of adolescents (N=478) with combined reduced-antigen-content diphtheria-tetanus-acellular pertussis vaccine (dTpa, Boostrix™, GlaxoSmithKline Belgium) containing 0.5mg, 0.3mg or 0.133mg of aluminium was assessed. The immunogenicity, reactogenicity and safety of a decennial booster dTpa dose were also investigated. METHODS: Young adults vaccinated as adolescents in the initial booster study were invited to participate in an assessment of antibody persistence at years 8.5 and 10, and to receive a dTpa booster dose at year 10 with immunogenicity assessment one month later. Those who originally received the 0.5mg or 0.3mg formulations received the same vaccine at year 10. Those in the 0.133mg group received the 0.5mg formulation. Reactogenicity and safety endpoints were captured until 30 days after booster vaccination. RESULTS: Prior to the decennial booster at year 8.5 and year 10, all participants had seroprotective antibodies for diphtheria (ELISA or neutralisation assay) and tetanus. At least 77.8% were seropositive for anti-pertussis toxin (PT) antibodies at year 8.5 and 82.8% at year 10. All participants were seropositive for antibodies for filamentous haemagglutinin and pertactin at both time points. The decennial booster dose induced robust increases in antibody GMCs to all antigens. The post-booster anti-PT geometric mean concentration was 82.5EL.U/ml (95%CI 67.0-101.6) and 124.0 (103.5-148.5) in the 0.3mg and 0.5mg groups, respectively. The reactogenicity and safety profile of the decennial booster dose was consistent with the known safety profile of dTpa. No serious adverse events were reported. CONCLUSIONS: Decennial booster vaccination with either of the two licensed formulations of dTpa was highly immunogenic and well tolerated in young adults. Either formulation could be confidently used as a decennial booster. This study is registered at www.clinicaltrials.govNCT01147900. publisher: Elsevier articletitle: Decennial administration in young adults of a reduced-antigen content diphtheria, tetanus, acellular pertussis vaccine containing two different concentrations of aluminium journaltitle: Vaccine articlelink: http://dx.doi.org/10.1016/j.vaccine.2014.10.049 content_type: article copyright: Copyright © 2014 GlaxoSmithKline and the Authors. Published by Elsevier Ltd. ispartof: Vaccine vol:33 issue:26 pages:3026-3034 ispartof: location:Netherlands status: published

Regulatory bodies in The Philippines, Sri Lanka, and India require post-marketing surveillance to provide additional safety data on Rotarix™ in real-life settings. In such studies conducted in The Philippines (November 2006 to July 2012; NCT00353366), Sri Lanka (November 2008 to August 2009; NCT00779779), and India (August 2009 to April 2010; NCT00938327), 2 doses of Rotarix™ were administered according to the local prescribing information (PI). The occurrence of at least Grade "2"/"3" solicited adverse event (AE) (fever, vomiting, or diarrhea), within 15 days in The Philippines or 8 days in Sri Lanka and India; unsolicited AEs within 31 days and serious adverse events (SAEs) throughout the study were recorded. Of the 1494, 522, and 332 infants enrolled in The Philippines, Sri Lanka, and India, 14.7% 14.9% and 12.7% infants, respectively recorded at least Grade "2"/"3" solicited AEs. The most commonly reported solicited AEs were irritability in The Philippines (32.2% post-Dose-1; 23.5% post-Dose-2) and India (23.0% post-Dose-1; 13.2% post-Dose-2), and fever (18.0% post-Dose-1; 20.2% post-Dose-2) in Sri Lanka. Unsolicited AEs were recorded in 24.5% (The Philippines), 4.8% (Sri Lanka), and 6.9% (India) of infants. Forty-one SAEs were recorded in the Philippines of which 6 (decreased oral intake with increased sleeping time and constipation; pneumonia, urinary tract infection, and intussusception) were considered by the investigators as causally related to vaccination. One vaccine-unrelated SAE occurred in a Sri Lankan infant. All SAEs resolved and the infants recovered. Two doses of Rotarix™, administered to healthy infants according to local PI, were well tolerated in The Philippines, Sri Lanka, and India.

The introduction of combination vaccines plays a significant role in increasing vaccine acceptance and widening vaccine coverage. Primary vaccination against diphtheria, tetanus, pertussis, poliomyelitis and Haemophilus influenza type b (Hib) diseases has been implemented in Vietnam. In this study we evaluated the safety and reactogenicity of combined diphtheria-tetanus-pertussis-inactivated polio (DTPa-IPV)/Hib vaccine when administered as a booster dose in 300 healthy Vietnamese children

Clinical trials of the human rotavirus vaccine Rotarix™ (RV1) have demonstrated significant reductions in severe rotavirus gastroenteritis (RVGE) in children worldwide. However, no correlate of vaccine efficacy (VE) has yet been established. This paper presents 2 analyses which aimed to investigate whether serum anti-RV IgA measured by ELISA 1 or 2 mo post-vaccination can serve as a correlate of efficacy against RVGE: (1) In a large Phase III efficacy trial (Rota-037), the Prentice criteria for surrogate endpoints was applied to anti-RV IgA seropositivity 1 mo post-vaccination. These criteria determine whether a significant vaccine group effect can be predicted from the surrogate, namely seropositivity (anti-RV IgA concentration >20 U/mL); (2) Among other GSK-sponsored RV1 VE studies, 8 studies which assessed immunogenicity at 1 or 2 mo post-vaccination in all or a sub-cohort of enrolled subjects and had at least 10 RVGE episodes were included in a meta-analysis to measure the regression between clinical VE and VE predicted from immunogenicity (VE1). In Rota-037, anti-RV IgA seropositivity post-vaccination was associated with a lower incidence of any or severe RVGE, however, the proportion of vaccine group effect explained by seropositivity was only 43.6% and 32.7% respectively. This low proportion was due to the vaccine group effect observed in seronegative subjects. In the meta-analysis, the slope of the regression between clinical VE and VE1 was statistically significant. These two independent analyses support the hypothesis that post-vaccination anti-RV IgA seropositivity (antibody concentration ≥20 U/mL) may serve as a useful correlate of efficacy in clinical trials of RV1 vaccines.

An integrated analysis of safety and reactogenicity data was undertaken for 28 randomized, placebo-controlled, double-blind Phase II and III trials (DBRCTs) of the oral live-attenuated human rotavirus vaccine, Rotarix™ (GlaxoSmithKline Vaccines). Healthy infants aged 6–20 wk received 2 or 3 doses of vaccine (n = 56562) or placebo (n = 45512) at 4- to 8-wk intervals. Solicited adverse events (AEs) were recorded for 8 d after each dose of vaccine or placebo. Unsolicited AEs, serious AEs (SAEs), and deaths were evaluated over 31-d post-vaccination follow-up periods. 95% confidence intervals (CIs) for the relative risk (RR) across studies excluding “1.0” signified potential imbalances between the 2 groups. The incidence of each solicited AE of any or Grade 3 severity was similar between groups. The incidence of all unsolicited AEs of any (RR = 0.99 [95% CI: 0.94–1.04]; P = 0.72) or Grade 3 severity (RR = 0.91 [95% CI: 0.77–1.08]; P = 0.31) was similar between groups. A significantly higher proportion of SAEs were reported in the placebo group compared with the vaccine group (RR = 0.9 [95% CI: 0.82–0.98]; P = 0.01). The incidence of death was low and similar between the 2 groups (0.13% in the vaccine group and 0.11% in the placebo group; RR = 1.14 [95% CI: 0.78–1.68]; P = 0.54). Very few cases of intussusception were reported (11 and 7 in the vaccine and placebo groups, respectively; RR = 1.39 [95% CI: 0.49–4.27]; P = 0.66). In conclusion, results of this analysis of DBRCTs show that the human rotavirus vaccine Rotarix™ has a reactogenicity and safety profile similar to placebo.

Rotaviruses (RV) are a major cause of severe gastroenteritis (GE) in children aged 10%. The number of unsolicited symptoms and SAEs reported was similar between both groups. Thirteen deaths (RIX4414 = 6; placebo = 7) occurred during the study. All SAEs and deaths in the RIX4414 group were considered unrelated to vaccination. Two oral doses of RIX4414 vaccine provided a substantial level of protection against severe RVGE in Chinese children during the first two years of life.

We report the findings of three randomized, double-blind, placebo-controlled Phase I studies undertaken to support licensure of the liquid formulation of the human G1P[8] rotavirus (RV) vaccine (RIX4414; GlaxoSmithKline Biologicals SA) in China. Healthy adults aged 18-45 y (n=48) and children aged 2-6 y (n=50) received a single dose of the human RV vaccine or placebo. Healthy infants (n=50) aged 6-16 weeks at the time of first vaccination received two oral doses of the human RV vaccine or placebo according to a 0, 1 mo schedule. In infants, blood samples were collected prior to vaccination and one month post-dose 2 to assess anti-RV IgA antibody concentrations using ELISA. Stool samples were collected from all infants on the day of each vaccination, at 7 and 15 d after each vaccination and one month post-dose 2. Stool samples were analyzed by ELISA for detection of RV antigen to assess RV antigen excretion. The reactogenicity profile of the human RV vaccine was found to be comparable to that of placebo in all age groups studied. The anti-RV IgA antibody seroconversion rate in infants after two vaccine doses was 86.7% (95% CI: 59.5-98.3). Vaccine take in infants who received the liquid human RV vaccine was 86.7% (95% CI: 59.5-98.3). A Phase III efficacy study of the human RV vaccine in the infant population in China has now been completed (ROTA-075/NCT01171963).

© 2016 The Author(s). Published with license by Taylor & Francis. © GSK Biologicals SA.Variability in rotavirus gastroenteritis (RVGE) epidemiology can influence the optimal vaccination schedule. We evaluated regional trends in the age of RVGE episodes in low- to middle- versus high-income countries in three continents. We undertook a post-hoc analysis based on efficacy trials of a human rotavirus vaccine (HRV; Rotarix™, GSK Vaccines), in which 1348, 1641, and 5250 healthy infants received a placebo in Europe (NCT00140686), Africa (NCT00241644), and Asia (NCT00197210, NCT00329745). Incidence of any/severe RVGE by age at onset was evaluated by active surveillance over the first two years of life. Severity of RVGE episodes was assessed using the Vesikari-scale. The incidence of any RVGE in Africa was higher than in Europe during the first year of life (≤2.78% vs. ≤2.03% per month), but much lower during the second one (≤0.86% versus ≤2.00% per month). The incidence of severe RVGE in Africa was slightly lower than in Europe during the first year of life. Nevertheless, temporal profiles for the incidence of severe RVGE in Africa and Europe during the first (≤1.00% and ≤1.23% per month) and second (≤0.53% and ≤1.13% per month) years of life were similar to those of any RVGE. Any/severe RVGE incidences peaked at younger ages in Africa vs. Europe. In high-income Asian regions, severe RVGE incidence (≤0.31% per month) remained low during the study. The burden of any RVGE was higher earlier in life in children from low- to middle- compared with high-income countries. Differing rotavirus vaccine schedules are likely warranted to maximize protection in different settings.

Purpose: According to regulations from the Ministry of Food and Drug Safety in Korea, additional safety information on the use of Rotarix™ vaccine (RIX4414; GSK, Belgium) in ≥3000 evaluable Korean infants was required following vaccine registration. In order to comply with these regulations, we conducted a 6-year open, non-comparative, multicenter post-marketing surveillance (NCT00750893). Methods: During this time, the original lyophilized vaccine formulation of RIX4414 was replaced by a liquid formulation. Healthy infants aged ≥6 weeks were enrolled and given 2 doses of the RIX4414 vaccine, separated by an interval of ≥4 weeks. The overall incidence of adverse events (AEs) (expected and unexpected) was then assessed for up to 30 days along with the incidence of serious adverse events (SAEs). Adverse drug reactions (ADRs: any AE whose causality to the drug could not be ruled out) were identified. Results: A total of 3040 children (mean age: 9.55 weeks) were analyzed. One or more expected AE was experienced by 30.5% infants and 8.6% had an ADR. The most commonly seen expected AE was irritability (14.0%). One or more unexpected AE was seen in 32.5% infants and 3.1% experienced an ADR. The most commonly seen unexpected AE was upper respiratory tract infection (8.7%). Of 34 SAEs recorded in 24 subjects, none were related to vaccination. Conclusions: We conclude that this 6-year surveillance showed both formulations of RIX4414 to have acceptable safety profiles when administered to Korean infants according to local prescribing recommendations and current clinical practice.

RIX4414 (Rotarix™), has shown high efficacy during the first 2-years of life. A 2-year randomized, double-blind, placebo-controlled trial in Singapore, Hong Kong, and Taiwan was extended for another year. Infants (6-17 weeks) received 2-doses (1-2 months apart) of RIX4414 (n=5359) or placebo (n=5349). During the third-year follow-up, 4359 (RIX4414) and 4328 (placebo) infants were monitored. 64 (1.2%) and 2 (0.04%) infants in the placebo and RIX4414 groups, respectively, reported severe rotavirus-gastroenteritis (RVGE), resulting in a vaccine efficacy of 96.9% (95% CI [88.3-99.6]). Efficacy was 100% (67.5-100) in the third-year. RIX4414 was efficacious against G1 (100.0% [84.8-100]) and pooled non-G1 RV types (94.9% [80.2-99.4]). This study shows that the vaccine is highly efficacious, regardless of circulating RV-types, up to the first 3 years of life in affluent Asian urban populations.

Rotavirus is the main cause of severe gastroenteritis and diarrhea in infants and young children less than 5 years of age. Potential impact of breast-feeding on the efficacy and immunogenicity of human rotavirus G1P[8] vaccine was examined in this exploratory analysis.Healthy infants (N = 3994) aged 6-14 weeks who received 2 doses of human rotavirus vaccine/placebo according to a 0-1 or 0-2 month schedule were followed for rotavirus gastroenteritis during 2 epidemic seasons. Rotavirus IgA seroconversion rate (anti-IgA antibody concentration ≥ 20 mIU/mL) and geometric mean concentrations were measured prevaccination and 1-2 months post-dose 2. Vaccine efficacy against any and severe rotavirus gastroenteritis was analyzed according to the infants being breast-fed or exclusively formula-fed at the time of vaccination.Antirotavirus IgA seroconversion rate was 85.5% (95% confidence interval [CI]: 82.4-88.3) in breast-fed and 89.2% (95% CI: 84.2-93) in exclusively formula-fed infants; geometric mean concentrations in the respective groups were 185.8 U/mL (95% CI: 161.4-213.9) and 231.5 U/mL (95% CI: 185.9-288.2). Vaccine efficacy was equally high in breast-fed and exclusively formula-fed children in the first season but fell in breast-fed infants in the second rotavirus season. During the combined 2-year efficacy follow-up period, vaccine efficacy against any rotavirus gastroenteritis was 76.2% (95% CI: 68.7-82.1) and 89.8% (95% CI: 77.6-95.9) and against severe rotavirus gastroenteritis 88.4% (95% CI: 81.6-93) and 98.1% (95% CI: 88.2-100) in the breast-fed and exclusively formula-fed infants, respectively.The difference in immunogenicity of human rotavirus vaccine in breast-fed and exclusively formula-fed infants was small. Vaccine efficacy was equally high in breast-fed and exclusively formula-fed children in the first season. Breast-feeding seemed to reduce slightly the efficacy in the second season.

Transmission of excreted vaccine-derived infectious virus from vaccinated to unvaccinated individuals is possible within close contacts. This randomized (1:1), double-blind study evaluated the potential for transmission of human rotavirus vaccine strain, HRV (Rotarix™) from vaccine recipients to unvaccinated close contacts (twins). 100 pairs of healthy twins aged 6–14 weeks at the time of Dose 1 of HRV vaccine/placebo were enrolled and one randomly selected twin from each pair received two vaccine doses and the other received placebo doses (at 2 and 4 months of age). Presence of vaccine strain in the stool samples of placebo recipients was an indicator of transmission. Serial stool samples were tested for rotavirus using ELISA at pre-determined time points; rotavirus positive stool samples were tested with RT-PCR and reverse hybridization assay to identify G1P[8] vaccine strain. If G1P[8] vaccine strain was detected, the complete genome was sequenced to assess the similarity between viral isolates. Immunogenicity and safety of HRV vaccine in transmission cases was assessed. 15 transmission cases were reported in 80 evaluable twins who received placebo and the transmission rate was 18.8% (95% CI: 10.9–29.0%). None of the transmission cases was associated with gastroenteritis symptoms. Anti-rotavirus IgA seroconversion was 62.5% (95% CI: 51.0–73.1%) (HRV) and 21.3% (95% CI: 12.9–31.8%) (placebo) 7-weeks post-Dose 2; seroconversion in transmission cases was 26.7% (95% CI: 7.8–55.1%). Genetic variations or amino acid substitutions in transmission cases were similar to that seen in corresponding vaccine recipients. Transmission of HRV vaccine strain to unvaccinated twins living in close contact occurred, however, they were not associated with increased of gastroenteritis. Whether transmission leads to indirect protection among unvaccinated individuals remains unknown at this stage.

A phase III, randomized, double-blind study evaluated the efficacy, reactogenicity, safety and immunogenicity of a human rotavirus vaccine, RIX4414 in Japanese infants aged 6-14 weeks when administered as two doses (0, 1-month schedule). Efficacy against any and severe rotavirus gastroenteritis leading to medical intervention caused by circulating wild-type rotavirus from two weeks post-Dose 2 until two years of age was 79.3% (95% CI: 60.5-89.8%) and 91.6% (95% CI: 62.4-99.1%), respectively. Solicited, unsolicited symptoms and serious adverse events were reported at a similar frequency in both groups. Serum anti-rotavirus antibody seroconversion rate one-month post-Dose 2 was 85.3% (95% CI: 68.9-95%) in RIXX4414 group. RIX4414 was efficacious, well-tolerated and immunogenic in Japanese infants and introduction of vaccination could help in reducing the disease burden.

BACKGROUND: Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. METHODS: We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:1:1 ratio to receive two doses of vaccine (in addition to one dose of placebo) or three doses of vaccine--the pooled vaccine group--or three doses of placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were graded with the use of the Vesikari scale. RESULTS: A total of 4939 infants were enrolled and randomly assigned to one of the three groups; 1647 infants received two doses of the vaccine, 1651 infants received three doses of the vaccine, and 1641 received placebo. Of the 4417 infants included in the per-protocol efficacy analysis, severe rotavirus gastroenteritis occurred in 4.9% of the infants in the placebo group and in 1.9% of those in the pooled vaccine group (vaccine efficacy, 61.2%; 95% confidence interval, 44.0 to 73.2). Vaccine efficacy was lower in Malawi than in South Africa (49.4% vs. 76.9%); however, the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa (6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year). Efficacy against all-cause severe gastroenteritis was 30.2%. At least one serious adverse event was reported in 9.7% of the infants in the pooled vaccine group and in 11.5% of the infants in the placebo group. CONCLUSIONS: Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life. (ClinicalTrials.gov number, NCT00241644.)

This study was undertaken to assess the immunogenicity, reactogenicity and safety of two doses of an oral live-attenuated human rotavirus vaccine, strain RIX4414 (Rotarix()) in an Indian setting.The seroconversion rate observed one month post-dose 2 in the RIX4414 group 58.3% [95% CI: 48.7; 67.4] was significantly higher when compared to the placebo group 6.3%; [95% CI: 2.5; 12.5]. The reactogenicity and safety profile was similar for both groups.Healthy infants (N = 363), approximately eight weeks of age were enrolled to receive two doses of RIX4414 vaccine (n = 182) or placebo (n = 181) separated by one month. To assess the immune response, blood samples were taken before vaccination and one month post-dose 2 of RIX4414/placebo. Solicited symptoms were collected for eight-days post each dose and safety data was collected throughout the study.Two doses of RIX4414 (Rotarix()) were immunogenic, had a good safety profile and were well-tolerated when administered to healthy Indian infants.ClinicalTrials.gov; NCT00289172; eTrack 103792.

The 2-dose, oral live attenuated human G1P[8] rotavirus vaccine (RIX4414) is highly effective against rotavirus gastroenteritis caused by circulating G1 and non-G1 types. An integrated analysis on vaccine efficacy was undertaken to obtain more precise estimates of the overall protective effect of the RIX4414 vaccine against rotavirus gastroenteritis due to common rotavirus types (G1, G3, G4, G9, P[8]) and less commonly encountered strains such as G2P[4] across heterogenous settings.: The studies used in the integrated analysis were all previously reported randomized, double-blind, placebo-controlled, phase II and III trials with at least 1 report of rotavirus gastroenteritis in the efficacy follow-up period (up to 1 year of age or end of first RV epidemic season after vaccination). The integrated analysis was performed for all circulating rotavirus strains sharing G and/or P genotype and not sharing G or P genotype with the vaccine strain. Vaccine efficacy was estimated as 1 minus rate of rotavirus gastroenteritis relative to placebo, using exact Poisson rate ratio stratified by study.: The integrated estimates for vaccine efficacy against severe rotavirus gastroenteritis were 87.43% (95% confidence interval [CI]: 78.89-92.86) for G1P[8] strains, 71.42% (95% CI: 20.12-91.11) for G2P[4] strains, 90.19% (95% CI: 55.51-98.94) for G3P[8] strains, 93.37% (95% CI: 51.50-99.85) for G4P[8] strains, and 83.76% (95% CI: 71.18-91.28) for G9P[8] strains. The integrated estimates for vaccine efficacies against rotavirus gastroenteritis of any severity were 82.57% (95% CI: 73.91-88.56) for G1P[8] strains, 81.04% (95% CI: 31.58-95.76) for G2P[4] strains, 87.66% (95% CI: 34.57-98.76) for G3P[8] strains, 84.86% (95% CI: 50.92-96.41) for G4P[8] strains, and 60.64% (95% CI: 38.15-74.96) for G9P[8] strains.: Two doses of RIX4414 provide overall good clinical protection against all cases of rotavirus gastroenteritis and comparable, high clinical protection against severe rotavirus gastroenteritis caused by circulating rotavirus strains with and without G and P genotypes shared with the vaccine strain, such as G2P[4].

Introduction: In recent years, acellular pertussis combination vaccines have facilitated compliance with and coverage of the national immunisation programme in Singapore. This phase-II study (Rota-007) evaluated the immunogenicity, reactogenicity and safety of a DTPaIPV/Hib combined vaccine when co-administered with a rotavirus vaccine. Materials and Methods: A total of 2464 children aged 3 months were vaccinated with DTPa-IPV/Hib together with a randomised 1:3 ratio of either placebo (n = 653) or 1 of 3 different formulations of a rotavirus vaccine. Blood samples were collected for immunogenicity analysis 1 month after the third DTPa-IPV/Hib vaccine dose in a subset of subjects (n = 640). Local and general reactogenicity and unsolicited adverse events were recorded during the follow-up after each vaccination. Results: Serological analysis showed >95% response for all antigens in the co-administered DTPa-IPV/Hib vaccine, with no difference between the rotavirus vaccine and placebo groups. No differences in adverse events and reactogenicity were reported in the rotavirus vaccine and placebo groups. Only 0.2% of the subjects reported Grade 3 adverse events. Three subjects (from the vaccine groups) died during the study, which were assessed by the investigators as unrelated to vaccination. No deaths were reported in the placebo group. Conclusion: The combined DTPaIPV/Hib vaccine is safe, well tolerated and highly immunogenic when given alone or coadministered with the rotavirus vaccine for infants in Singapore. Key words: Paediatric, Vaccination

The response to booster vaccination at 15-18 months of age and the presence of immune memory in 10-month old children, primed with a new combined diphtheria-tetanus-hepatitis B-whole cell pertussis vaccine extemporaneously mixed with Haemophilus influenzae type b-tetanus toxoid conjugate (DTPw-HBV/Hib) from new antigen sources and containing 2.5 microg polyribosyl-ribitol-phosphate (PRP) was assessed. Primary vaccination with the new DTPw-HBV/Hib vaccine was immunogenic and of comparable tolerability to commercially available Tritanrix HepB/Hiberix. Children were boosted with DTPw-HBV, DTPw-HBV/Hib or separate DTPw-HBV+Hiberix. Immune memory was assessed through administration of 10 microg PRP polysaccharide. Anti-PRP antibody GMCs increased substantially after the challenge in DTPw-HBV/Hib-primed subjects indicating the presence of immune memory. One month after the booster dose, 100% of subjects had seroprotective antibody concentrations against PRP, diphtheria and tetanus, >95% were seroprotected against hepatitis B, > or =94.0% had a pertussis booster response. Substantial increases in antibody GMCs against all antigens were observed. Swelling >20 mm was the most common Grade 3 solicited symptom reported (up to 26.0% of subjects). Fever >39.5 degrees C was uncommon (>2.5%). Eleven large swelling reactions were reported; none involved an adjacent joint. One serious adverse event occurred that was considered unrelated to vaccination. This new DTPw-HBV/Hib vaccine with new vaccine components and 2.5 microg PRP induced effective priming against Hib evidenced by a vigorous anamnestic response on exposure to PRP polysaccharide. The booster dose was immunogenic and the safety profile was acceptable. Combined DTPw-HBV and DTPw-HBV/Hib vaccines using new vaccine antigen sources will promote continued supply of combined DTPw-based vaccines to global mass vaccination campaigns.

Introduction: The world’s first rotavirus vaccine, Rotashield® or RRV-TV, was registered in the US in 1998, but withdrawn within a year because of an observed association with intussusception (IS). Surveillance for IS has consequently become important in safety monitoring of new-generation rotavirus vaccines during development. Post-marketing surveillance is also important, and requires the availability of local baseline epidemiology data on IS. Materials and Methods: An eight-year study of IS in children under 2 years of age in Singapore was performed by retrospective review of admissions to KK Women’s and Children’s Hospital, the main paediatric hospital, from 1997 to 2001, followed by prospective surveillance of all hospitals from 2001 to 2004, using the case definition of the Brighton Collaboration Intussusception Working Group. Results: The average IS incidence was 60 per 100,000 in under-ones, and 32 per 100,000 in under-twos, with a downward trend between 1999 and 2004. Ninety-two per cent of subjects were aged below one year, with 51% aged 6 months to 11 months. The mean age at which IS occurred increased from 6.4 months to 12.5 months over the study period. The male-to-female ratio was 1.3:1. No trend in IS numbers was observed over different months of the year. Conclusion: IS in Singapore shows no seasonality, but has demonstrated a trend of decreasing incidence in recent years. While highest in the first year of life, the risk of IS is increasing in the second year of life. Males have a slightly higher risk. Key words: Adverse effects, Rotavirus vaccines

Background At present, no rotavirus vaccine is commercially available for use worldwide. Hence, a live, attenuated monovalent vaccine was developed with human strain RIX4414 (G1P1A P[8] specificity). Vaccination trials involving infants are ongoing in developed and developing countries. Methods This study was a randomized, double-blind, placebo-controlled trial conducted at pediatric hospitals and polyclinics in Singapore for the evaluation of the immunogenicity, reactogenicity, and efficacy of 2 oral doses of RIX4414. In total, 2464 healthy infants (who were 11-17 weeks old when the first dose was administered, which is in accordance with the local immunization schedule) were enrolled to receive RIX4414 at 3 concentrations of virus (10(4.7), 10(5.2), or 10(6.1) focus-forming units) or placebo at 1-month intervals, concomitantly with routinely administered infant vaccines. Results The RIX4414 vaccine was highly immunogenic, and virtually all vaccine recipients (98%-100%) experienced "vaccine take" (i.e., a combined immunogenicity end point based on seroconversion and/or shedding of RIX4414 in postvaccination stool samples) after receipt of 2 doses at all 3 dosage levels. Depending on the virus concentration, the anti-rotavirus IgA seroconversion rate varied from 76% (95% confidence interval [CI], 68%-83%) to 91% (95% CI, 85%-95%). Two doses of RIX4414 were well tolerated, with no increase in high fever, severe diarrhea, or vomiting after either dose or with increased viral concentration, compared with placebo. There was no observed interference with routine vaccinations of infants when RIX4414 was coadministered. The calculated efficacy of RIX4414 against rotavirus gastroenteritis was 82% (P = .046); however, this result was considered to be of limited conclusive value because of the low number of rotavirus gastroenteritis episodes identified during the follow-up period. Conclusions The live, attenuated rotavirus vaccine (RIX4414) was well tolerated and highly immunogenic in Singaporean infants. The immunogenicity of routinely administered infant vaccines was not impaired by concomitant administration of RIX4414 vaccine.

Maternal immunization is an effective strategy to prevent and/or minimize the severity of infectious diseases in pregnant women and their infants. Based on the success of vaccination programs to prevent maternal and neonatal tetanus, maternal immunization has been well received in the United States and globally as a promising strategy for the prevention of other vaccine-preventable diseases that threaten pregnant women and infants, such as influenza and pertussis. Given the promise for reducing the burden of infectious conditions of perinatal significance through the development of vaccines against relevant pathogens, the Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH) sponsored a series of meetings to foster progress toward clinical development of vaccines for use in pregnancy. A multidisciplinary group of stakeholders convened at the NIH in December 2013 to identify potential barriers and opportunities for scientific advancement in maternal immunization.

In January 2010, porcine circovirus type 1 (PCV1) DNA was unexpectedly detected in the oral live-attenuated human rotavirus vaccine, Rotarix™ (GlaxoSmithKline [GSK] Vaccines) by an academic research team investigating a novel, highly sensitive analysis not routinely used for adventitious agent screening. GSK rapidly initiated an investigation to confirm the source, nature and amount of PCV1 in the vaccine manufacturing process and to assess potential clinical implications of this finding. The investigation also considered the manufacturer’s inactivated poliovirus (IPV)-containing vaccines, since poliovirus vaccine strains are propagated using the same cell line as the rotavirus vaccine strain. Results confirmed the presence of PCV1 DNA and low levels of PCV1 viral particles at all stages of the Rotarix™ manufacturing process. PCV type 2 DNA was not detected at any stage. When tested in human cell lines, productive PCV1 infection was not observed. There was no immunological or clinical evidence of PCV1 infection in infants who had received Rotarix™ in clinical trials. PCV1 DNA was not detected in the IPV-containing vaccine manufacturing process beyond the purification stage. Retrospective testing confirmed the presence of PCV1 DNA in Rotarix™ since the initial stages of its development and in vaccine lots used in clinical studies conducted pre- and post-licensure. The acceptable safety profile observed in clinical trials of Rotarix™ therefore reflects exposure to PCV1 DNA. The investigation into the presence of PCV1 in Rotarix™ could serve as a model for risk assessment in the event of new technologies identifying adventitious agents in the manufacturing of other vaccines and biological products.

Rotavirus (RV) infection is the primary cause for childhood gastroenteritis worldwide. In Korea, RV infection is most common among children less than 5 years of age. This post-licensure study was conducted to further evaluate the RV vaccine (RIX4414) to provide additional local clinical data to the Korean Food and Drug Association. Healthy infants aged 6-12 weeks were enrolled to receive two doses of either RIX4414 or placebo as per 0, 1-2 month schedule. Blood samples were collected before dose-1 and one month post-dose-2 of RIX4414/placebo to assess serum anti-RV IgA antibody concentrations using ELISA. Gastroenteritis stool samples were tested for the presence of RV using ELISA. RV positive samples were subjected to further analysis for G and P typing. Among 684 infants enrolled and vaccinated, 432 infants (RIX4414=318; placebo=114) were included in the according-to-protocol cohort for immunogenicity. The anti-RV IgA antibody seroconversion rates in the RIX4414 group following one month post-dose-2 were 88.1% (95% CI: 84.0-91.4) and the corresponding geometric mean concentration in the RIX4414 group was 208.5 U/ml (95% CI: 174.2-249.5). Occurrence of solicited and unsolicited adverse events were similar in both, RIX4414 and placebo groups. None of the gastroenteritis stool samples tested positive for RV and no fatal SAEs were reported in either groups. The two-dose regimen of RIX4414 was observed to be immunogenic with a similar safety profile as compared to the placebo group, when administered to healthy Korean infants.

The efficacy of a rotavirus vaccine against severe rotavirus gastroenteritis when coadministered with routine Expanded Program on Immunization (EPI) vaccines including oral polio vaccine (OPV) was evaluated in this study.Double-blind, randomized (2:1), placebo-controlled study conducted across 6 Latin American countries. Healthy infants (N = 6568) 6 to 12 weeks of age received 2 doses of RIX4414 vaccine or placebo following a 0, 1- to 2-month schedule. Routine vaccines including OPV were coadministered according to local EPI schedule. Vaccine efficacy (VE) against severe rotavirus gastroenteritis caused by circulating wild-type rotavirus from 2 weeks post-Dose 2 until 1 year of age was calculated with 95% confidence interval [CI]. Safety was assessed during the entire study period. Immunogenicity of RIX4414 and OPV was also assessed.During the efficacy follow-up period (mean duration = 7.4 months), 7 and 19 cases of severe rotavirus gastroenteritis were reported in the vaccine and placebo groups, respectively, with a VE of 81.6% (95% CI: 54.4-93.5). VE against severe rotavirus gastroenteritis caused by G1 type was 100% (95% CI:0-100) and 80.6% (95% CI: 51.4-93.2) against the pooled non-G1 rotavirus types, respectively. There was no difference (P = 0.514) in the incidence of serious adverse events reported in the 2 groups. Antirotavirus IgA seropositivity rate at 1 to 2 months post-Dose 2 was 61.4% (95% CI: 53.7-68.6) in the RIX4414 group; similar seroprotection rates (≥96.0%) against the 3 antipoliovirus types was observed 1 month post-Dose 3 of OPV in both groups.RIX4414 was highly efficacious against severe rotavirus gastroenteritis caused by the circulating wild-type rotavirus (G1 and non-G1) when coadministered with routine EPI vaccines including OPV.

Combination vaccines have been shown to improve the timeliness of vaccination and vaccine coverage. Safety and reactogenicity of combined diphtheria-tetanus-acellular pertussis-inactivated poliovirus and Haemophilus influenzae type b vaccine (DTPa-IPV/Hib, Infanrix IPV+Hib, GlaxoSmithKline Biologicals) was assessed in two clinical studies. In Study A, 2,590 subjects received DTPa-IPV/Hib at 3, 4 and 5 months of age with a booster at 18 months. In Study B, 702 subjects received the same schedule but with DTPa-hepatitis B-IPV/Hib (DTPa-HBV-IPV/Hib, Infanrix hexa, GlaxoSmithKline Biologicals) vaccine administered at 5 months of age. Reactogenicity was assessed for four days after each dose using diary cards. Serious adverse events (SAEs) were assessed until 24 months of age. The vaccines were well tolerated. After primary vaccination, irritability was the most frequently reported grade 3 general symptom (0.8% of doses in both studies). Fever (axillary)39 degrees C was infrequent (0.3% of doses in Study A; 0.5% of doses in Study B). After the booster dose, the most frequently reported grade 3 symptom was redness (5%) in Study A and pain (0.5%) in Study B. An axillary temperature39 degrees C was reported in 1.1% of subjects. Throughout the study period, 646 SAEs were reported, of which 6 SAEs were considered to be vaccination-related. The reactogenicity and safety profile of the combined DTPa-IPV/Hib vaccine was good when used for primary and booster vaccinations in over 3,000 Singaporean infants. Substitution of DTPa-IPV/Hib with DTPa-HBV-IPV/Hib at Month 5 reduced the number of injections required at this age by one.

BACKGROUND: rotavirus and human immunodeficiency virus (HIV) infections are a cause of great public health concern in developing countries. The current study evaluated the safety reactogenicity and immunogenicity of RIX4414 vaccine in asymptomatic or mildly symptomatic (clinical stages I and II according to WHO classification) HIV-infected South African infants. METHODS: a total of 100 HIV-positive infants aged 6 to 10 weeks enrolled in this double-blind 1:1 randomized placebo-controlled study were allocated into 2 groups to receive 3 doses of RIX4414 vaccine/placebo according to a 0- 1- and 2-month schedule. Routine vaccines were concomitantly administered. Solicited and unsolicited symptoms were recorded for 15 and 31 days after each dose respectively. Serious adverse events were recorded throughout the study period. Serum antirotavirus IgA concentrations (enzyme-linked immunosorbent assay cut-off >/= 20 U/mL) and the immunodeficiency status were determined at screening and 2 months post-Dose 3. Stool samples were analyzed for rotavirus using enzyme-linked immunosorbent assay at predetermined points and during diarrhea episodes. RESULTS: all symptoms (solicited and unsolicited) occurred at a similar frequency in both groups. Six fatal serious adverse events in RIX4414 and 9 in placebo groups were reported. At 2 months post-Dose 3 the seroconversion rates were 57.1% (95% CI: 34-78.2) in RIX4414 and 18.2% (95% CI: 5.2-40.3) in the placebo group. The mean absolute CD4 cell count CD4 percentage and HIV-1 viral load were comparable in both groups at screening and 2 months post-Dose 3. Rotavirus shedding peaked at Day 7 after Dose 1 of RIX4414 with prolonged shedding was observed in 1 infant only. CONCLUSIONS: : Three doses of RIX4414 vaccine was tolerated well by the South African HIV-positive infants. A satisfactory immune response was mounted without aggravating their immunologic or HIV condition.

Rotavirus gastroenteritis causes more than half a million deaths annually among children aged