RESUMO
BACKGROUND: GSK has modified the licensed monovalent bulk manufacturing process for its split-virion inactivated quadrivalent influenza vaccine (IIV4) to harmonize the process among different strains, resulting in an increased number of finished vaccine doses, while compensating for the change from inactivated trivalent influenza vaccine (IIV3) to IIV4. To confirm the manufacturing changes do not alter the profile of the vaccine, a clinical trial was conducted to compare IIV4 made by the currently licensed process with a vaccine made by the new (investigational) process (IIV4-I). The main objectives were to compare the reactogenicity and safety of IIV4-I versus IIV4 in all age groups, and to demonstrate the non-inferiority of the hemagglutination-inhibition (HI) antibody responses based on the geometric mean titer ratio of IIV4-I versus IIV4 in children. METHODS: The Phase III, randomized, double-blind, multinational study included three cohorts: adults (18-49 years; N = 120), children (3-17 years; N = 821), and infants (6-35 months; N = 940). Eligible subjects in each cohort were randomized 1:1 to receive IIV4-I or IIV4. Both vaccines contained 15 µg of hemagglutinin antigen for each of the four seasonal virus strains. Adults and vaccine-primed children received one dose of vaccine, and vaccine-unprimed children received two doses of vaccine 28 days apart. All children aged ≥9 years were considered to be vaccine-primed and received one dose of vaccine. RESULTS: The primary immunogenicity objective of the study was met in demonstrating immunogenic non-inferiority of IIV4-I versus IIV4 in children. The IIV4-I was immunogenic against all four vaccine strains in each age cohort. The reactogenicity and safety profile of IIV4-I was similar to IIV4 in each age cohort, and there was no increase in the relative risk of fever (≥38 °C) with IIV4-I versus IIV4 within the 7-day post-vaccination period in infants (1.06; 95% Confidence Interval: 0.75, 1.50; p = 0.786). CONCLUSIONS: The study demonstrated that in adults, children, and infants, the IIV4-I made using an investigational manufacturing process was immunogenic with a reactogenicity and safety profile that was similar to licensed IIV4. These results support that the investigational process used to manufacture IIV4-I is suitable to replace the current licensed process. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02207413 ; trial registration date: August 4, 2014.
Assuntos
Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Método Duplo-Cego , Feminino , Febre/etiologia , Testes de Inibição da Hemaglutinação , Humanos , Lactente , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Vacinas de Produtos Inativados/uso terapêuticoRESUMO
BACKGROUND: Almost 700 cases of human infection with avian influenza A/H7N9 have been reported since 2013. Pandemic preparedness strategies include H7N9 vaccine development. METHODS: We evaluated an inactivated H7N9 vaccine in an observer-blind study in healthy adults aged 18-64 years. Participants (420) were randomized to receive 1 of 4 AS03-adjuvanted vaccines (low or medium dose of hemagglutinin with AS03A or AS03B), one nonadjuvanted vaccine, or placebo. The coprimary immunogenicity objective determined whether adjuvanted vaccines elicited an immune response against the vaccine-homologous virus, 21 days after the second vaccine dose per US and European licensure criteria in the per-protocol cohort (n = 389). RESULTS: All adjuvanted vaccines met regulatory acceptance criteria. In groups receiving adjuvanted formulations, seroconversion rates were ≥85.7%, seroprotection rates ≥91.1%, and geometric mean titers ≥92.9% versus 23.2%, 28.6%, and 17.2 for the nonadjuvanted vaccine. The AS03 adjuvant enhanced immune response at antigen-sparing doses. Injection site pain occurred more frequently with adjuvanted vaccines (in ≤98.3% of vaccinees) than with the nonadjuvanted vaccine (40.7%) or placebo (20.0%). None of the 20 serious adverse events reported were related to vaccination. CONCLUSIONS: Two doses of AS03-adjuvanted H7N9 vaccine were well tolerated and induced a robust antibody response at antigen-sparing doses in healthy adults. CLINICAL TRIALS REGISTRATION: NCT01999842.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Subtipo H7N9 do Vírus da Influenza A/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Polissorbatos/administração & dosagem , Esqualeno/administração & dosagem , alfa-Tocoferol/administração & dosagem , Adolescente , Adulto , Anticorpos Antivirais/sangue , Combinação de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Voluntários Saudáveis , Humanos , Esquemas de Imunização , Vacinas contra Influenza/administração & dosagem , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Método Simples-Cego , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adulto JovemRESUMO
BACKGROUND: Commonly used trivalent vaccines contain one influenza B virus lineage and may be ineffective against viruses of the other B lineage. We evaluated the efficacy of a candidate inactivated quadrivalent influenza vaccine (QIV) containing both B lineages. METHODS: In this multinational, phase 3, observer-blinded study, we randomly assigned children 3 to 8 years of age, in a 1:1 ratio, to receive the QIV or a hepatitis A vaccine (control). The primary end point was influenza A or B confirmed by real-time polymerase chain reaction (rt-PCR). Secondary end points were rt-PCR-confirmed, moderate-to-severe influenza and rt-PCR-positive, culture-confirmed influenza. The vaccine efficacy and the effect of vaccination on daily activities and utilization of health care resources were assessed in the total vaccinated cohort (2584 children in each group) and the per-protocol cohort (2379 children in the QIV group and 2398 in the control group). RESULTS: In the total vaccinated cohort, 62 children in the QIV group (2.40%) and 148 in the control group (5.73%) had rt-PCR-confirmed influenza, representing a QIV efficacy of 59.3% (95% confidence interval [CI], 45.2 to 69.7), with efficacy against culture-confirmed influenza of 59.1% (97.5% CI, 41.2 to 71.5). For moderate-to-severe rt-PCR-confirmed influenza, the attack rate was 0.62% (16 cases) in the QIV group and 2.36% (61 cases) in the control group, representing a QIV efficacy of 74.2% (97.5% CI, 51.5 to 86.2). In the per-protocol cohort, the QIV efficacy was 55.4% (95% CI, 39.1 to 67.3), and the efficacy against culture-confirmed influenza 55.9% (97.5% CI, 35.4 to 69.9); the efficacy among children with moderate-to-severe influenza was 73.1% (97.5% CI, 47.1 to 86.3). The QIV was associated with reduced risks of a body temperature above 39°C and lower respiratory tract illness, as compared with the control vaccine, in the per-protocol cohort (relative risk, 0.29 [95% CI, 0.16 to 0.56] and 0.20 [95% CI, 0.04 to 0.92], respectively). The QIV was immunogenic against all four strains. Serious adverse events occurred in 36 children in the QIV group (1.4%) and in 24 children in the control group (0.9%). CONCLUSIONS: The QIV was efficacious in preventing influenza in children. (Funded by GlaxoSmithKline Biologicals; ClinicalTrials.gov number, NCT01218308.).
Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Criança , Pré-Escolar , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/genética , Vírus da Influenza B/imunologia , Vírus da Influenza B/isolamento & purificação , Vacinas contra Influenza/efeitos adversos , Influenza Humana/classificação , Influenza Humana/diagnóstico , Influenza Humana/imunologia , Masculino , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença , Método Simples-Cego , Vacinas de Produtos Inativados/imunologiaRESUMO
BACKGROUND: Cell-culture-derived (CC) influenza vaccine production methods could provide benefits over classical embryonated-egg technology, including a higher production capacity and the faster creation of a supply that meets demand. METHODS: A CC-inactivated split-virus influenza A/Indonesia/5/2005(H5N1) vaccine derived from the EB66 cell line (hereafter, "CC-H5N1") was investigated in a phase 1 randomized, blinded study. Healthy adults (n = 521) received 2 vaccine doses (days 0 and 21) of either investigational CC-H5N1 vaccine (1.9 µg or 3.75 µg of hemagglutinin antigen [HA] with the AS03 adjuvant system or 15 µg of plain HA), embryonated-egg-derived vaccines (3.75 µg of HA with AS03 or 15 µg of plain HA), or placebo. Assessment of the adjuvant effect and immunogenicity was performed using Center for Biologics Evaluation and Research acceptability criteria 21 days after dose 2. Safety was assessed until month 12. RESULTS: AS03-adjuvanted CC-H5N1 elicited a homologous hemagglutination inhibition antibody response that satisfied immunogenicity criteria 21 days after dose 2 and persisted at month 12. Adjuvant effect and immune response against a drift-variant strain were demonstrated. No vaccine-related serious adverse events were reported. The immunogenicity and safety of the CC-H5N1 formulation containing 3.75 µg of HA and AS03 appeared to be similar to those for the licensed egg-derived AS03-adjuvanted control vaccine. CONCLUSIONS: The feasibility of the EB66 cell line to produce an immunogenic influenza vaccine with acceptable safety profile was demonstrated. Antigen sparing was achieved through combination with AS03 adjuvant. This CC-H5N1 might contribute to the rapid access of vaccine in the event of an influenza A(H5N1) pandemic. CLINICAL TRIALS REGISTRATION: NCT01236040.
Assuntos
Adjuvantes Imunológicos/farmacologia , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Polissorbatos/farmacologia , Esqualeno/farmacologia , alfa-Tocoferol/farmacologia , Adjuvantes Imunológicos/efeitos adversos , Adolescente , Adulto , Animais , Anticorpos Antivirais/sangue , Linhagem Celular , Combinação de Medicamentos , Patos/embriologia , Células-Tronco Embrionárias , Feminino , Humanos , Vacinas contra Influenza/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polissorbatos/efeitos adversos , Método Simples-Cego , Esqualeno/efeitos adversos , Adulto Jovem , alfa-Tocoferol/efeitos adversosRESUMO
BACKGROUND: This phase 2/3, randomized, placebo-controlled, observer-blinded study assessed the immunogenicity, reactogenicity, and safety of an inactivated, split-virion H5N1 influenza vaccine (A/Indonesia/5/2005) in children aged 6 months through 17 years. METHODS: Children received 2 influenza vaccine doses 21 days apart, each containing 1.9 µg of hemagglutinin and AS03B adjuvant (5.93 mg of α-tocopherol). The randomization ratio was 8:3 for vaccine to placebo, with equal allocation between 3 age strata (6-35 months, 3-8 years, and 9-17 years). Immunogenicity against the vaccine strain was assessed 21 days after the first and second vaccine doses for all vaccinees, at day 182 for half, and at day 385 for the remaining half. Reactogenicity after each dose and safety up to 1 year after vaccination were evaluated. RESULTS: Within each age stratum, the lower limit of the 98.3% confidence interval for the day 42 seroprotection rate was ≥70%, thus fulfilling the US and European licensure criteria. The immune responses elicited by vaccine persisted well above baseline levels for 1 year. The vaccine was more reactogenic than placebo, but no major safety concerns were identified. CONCLUSIONS: AS03B-adjuvanted H5N1 influenza vaccine was immunogenic and showed an acceptable safety profile in all age groups studied. Clinical Trials Registration: NCT01310413.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Polissorbatos/administração & dosagem , Esqualeno/administração & dosagem , alfa-Tocoferol/administração & dosagem , Adolescente , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Combinação de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Lactente , Vacinas contra Influenza/efeitos adversos , Influenza Humana/imunologia , Influenza Humana/virologia , Masculino , Placebos/administração & dosagem , Polissorbatos/efeitos adversos , Método Simples-Cego , Esqualeno/efeitos adversos , Resultado do Tratamento , Vacinação/métodos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , alfa-Tocoferol/efeitos adversosRESUMO
BACKGROUND: Rates of varicella have decreased substantially in countries implementing routine varicella vaccination. Immunisation is possible with monovalent varicella vaccine or a combined measles-mumps-rubella-varicella vaccine (MMRV). We assessed protection against varicella in naive children administered one dose of varicella vaccine or two doses of MMRV. METHODS: This study was done in ten European countries with endemic varicella. Healthy children aged 12-22 months were randomised (3:3:1 ratio, by computer-generated randomisation list, with block size seven) to receive 42 days apart (1) two doses of MMRV (MMRV group), or (2) MMR at dose one and monovalent varicella vaccine at dose two (MMR+V group), or (3) two doses of MMR (MMR group; control). Participants and their parents or guardians, individuals involved in assessment of any outcome, and sponsor staff involved in review or analysis of data were masked to treatment assignment. The primary efficacy endpoint was occurrence of confirmed varicella (by detection of varicella zoster virus DNA or epidemiological link) from 42 days after the second vaccine dose to the end of the first phase of the trial. Cases were graded for severity. Efficacy analyses were per protocol. Safety analyses included all participants who received at least one vaccine dose. This trial is registered with ClinicalTrials.gov, number NCT00226499. FINDINGS: Between Sept 1, 2005, and May 10, 2006, 5803 children (mean age 14·2 months, SD 2·5) were vaccinated. In the efficacy cohort of 5285 children, the mean duration of follow-up in the MMRV group was 36 months (SD 8·8), in the MMR+V group was 36 months (8·5) and in the MMR group was 35 months (8·9). Varicella cases were confirmed for 37 participants in the MMRV group (two moderate to severe), 243 in the MMR+V group, and 201 in the MMR group. Second cases occurred for three participants (all in the MMR+V group). Varicella cases were moderate to severe for two participants in the MMRV group, 37 in the MMR+V group (one being a second case that followed a mild first case); and 117 in the MMR group. Efficacy of two-dose MMRV against all varicella was 94·9% (97·5% CI 92·4-96·6), and against moderate to severe varicella was 99·5% (97·5-99·9). Efficacy of one-dose varicella vaccine against all varicella was 65·4% (57·2-72·1), and against moderate to severe varicella (post hoc) was 90·7% (85·9-93·9). The most common adverse event in all groups was injection-site redness (up to 25% of participants). Within 15 days after dose one, 57·4% (95% CI 53·9-60·9) of participants in the MMRV group reported fever of 38°C or more, by contrast with 44·5% (41·0-48·1) with MMR+V, and 39·8% (33·8-46·1) with MMR. Eight serious adverse events were deemed related to vaccination (three MMRV, four MMR+V, one MMR). All resolved within the study period. INTERPRETATION: These results support the implementation of two-dose varicella vaccination on a short course, to ensure optimum protection from all forms of varicella disease. FUNDING: GlaxoSmithKline Vaccines.
Assuntos
Vacina contra Varicela/administração & dosagem , Varicela/imunologia , Varicela/prevenção & controle , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem , Adolescente , Criança , Europa (Continente) , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Resultado do Tratamento , Vacinas Combinadas/administração & dosagem , Adulto JovemRESUMO
BACKGROUND: The vaccine efficacy (VE) of 1 or 2 doses of AS03-adjuvanted influenza A(H1N1) vaccine relative to that of 2 doses of nonadjuvanted influenza A(H1N1) vaccine in children 6 months to <10 years of age in a multinational study conducted during 2010-2011. METHODS: A total of 6145 children were randomly assigned at a ratio of 1:1:1 to receive 2 injections 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine at dose 1 and saline placebo at dose 2, 2 doses 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine (the Ad2 group), or 2 doses 21 days apart of nonadjuvanted A/California/7/2009(H1N1) vaccine (the NAd2 group). Active surveillance for influenza-like illnesses continued from days 14 to 385. Nose and throat samples obtained during influenza-like illnesses were tested for A/California/7/2009(H1N1), using reverse-transcriptase polymerase chain reaction. Immunogenicity, reactogenicity, and safety were assessed. RESULTS: There were 23 cases of confirmed 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09) infection for the primary relative VE analysis. The VE in the Ad2 group relative to that in the NAd2 group was 76.8% (95% confidence interval, 18.5%-93.4%). The benefit of the AS03 adjuvant was demonstrated in terms of the greater immunogenicity observed in the Ad2 group, compared with the NAd2 group. CONCLUSION: The 4-8-fold antigen-sparing adjuvanted pandemic influenza vaccine demonstrated superior and clinically important prevention of A(H1N1)pdm09 infection, compared with nonadjuvanted vaccine, with no observed increase in medically attended or serious adverse events. These data support the use of adjuvanted influenza vaccines during influenza pandemics. Clinical Trials Registration. NCT01051661.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Influenza Humana/epidemiologia , Masculino , Estudos Prospectivos , Vacinação/métodosRESUMO
BACKGROUND: An inactivated quadrivalent influenza vaccine (QIV) was recently licenced in the US as a thimerosal-free formulation presented in a pre-filled syringe. A multidose presentation is preferred in some settings due to reduced acquisition and cold storage costs. We assessed the immunogenicity and safety of a thimerosal-containing QIV formulated using a new manufacturing process for presentation in multidose vials. METHODS: Two Phase III non-randomized studies separately evaluated inactivated trivalent influenza vaccine (TIV; 2010-2011; historical control) and a QIV (2011-2012). The QIV contained the same strains as the TIV plus an additional B strain. Both vaccines contained thimerosal to allow multidose presentation: this preservative was added to the QIV during the final formulation step using a new process, whereas it was added to the TIV early in the manufacturing process using an established method. The TIV study included 50 and 70 subjects aged 18-60 and >60 years, respectively; the QIV study included 56 subjects in each age stratum. Immunogenicity was assessed using hemagglutination-inhibition (HI) assays. Reactogenicity was assessed during the 4-day post-vaccination periods and unsolicited adverse events (AEs) were assessed during the 21-day post-vaccination periods. RESULTS: The TIV and QIV were immunogenic in both age strata. With the QIV and TIV respectively, the seroconversion rates were 48.2-62.7% and 71.4-83.7% for influenza A, and 33.9-62.5% and 67.3-72.9% for influenza B. With the QIV and TIV respectively, the seroprotection rates were 92.9-98.2% and 98.2-100% for influenza A, and 88.6-100% and 95.9-98.6% for influenza B. Pre-vaccination titers were higher in the QIV versus TIV study which confounds a direct comparison and likely explains the lower seroconversion rates observed in the QIV study. There were no safety concerns raised with TIV or QIV. CONCLUSIONS: The thimerosal-containing QIV formulated using a new process was immunogenic, conforming to regulatory acceptance criteria, with a reactogenicity and safety profile in line with the TIV manufactured using a licensed process. These results support acceptability of a manufacturing process change in which the thimerosal preservative is added at the point at which batches are filled into multidose vials. TRIAL REGISTRATION: These trials were registered at ClinicalTrials.gov: NCT01440387; NCT01153685.
Assuntos
Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/química , Influenza Humana/prevenção & controle , Adolescente , Adulto , Composição de Medicamentos , Feminino , Estudo Historicamente Controlado , Humanos , Vacinas contra Influenza/efeitos adversos , Influenza Humana/imunologia , Masculino , Pessoa de Meia-Idade , Timerosal/administração & dosagem , Timerosal/efeitos adversos , Timerosal/química , Adulto JovemRESUMO
BACKGROUND: Two antigenically distinct influenza B lineages have cocirculated since 2001, yet trivalent influenza vaccines (TIVs) contain 1 influenza B antigen, meaning lineage mismatch with the vaccine is frequent. We assessed a candidate inactivated quadrivalent influenza vaccine (QIV) containing both B lineages vs TIV in healthy children aged 3-17 years. METHODS: Children were randomized 1:1:1 to receive QIV or 1 of 2 TIVs (either B/Victoria or B/Yamagata lineage; N = 2738). Hemagglutination-inhibition assays were performed 28 days after 1 or 2 doses in primed and unprimed children, respectively. Immunological noninferiority of QIV vs TIV against shared strains, and superiority against alternate-lineage B strains was based on geometric mean titers (GMTs) and seroconversion rates. Reactogenicity and safety were also assessed (Clinicaltrials.gov NCT01196988). RESULTS: Noninferiority against shared strains and superiority against alternate-lineage B strains was demonstrated for QIV vs TIV. QIV was highly immunogenic; seroconversion rates were 91.4%, 72.3%, 70.0%, and 72.5% against A/H1N1, A/H3N2, B/Victoria, and B/Yamagata, respectively. Reactogenicity and safety of QIV was consistent with TIV. CONCLUSIONS: QIV vs TIV showed superior immunogenicity for the additional B strain without interfering with immune responses to shared strains. QIV may offer improved protection against influenza B in children compared with current trivalent vaccines.
Assuntos
Anticorpos Antivirais/imunologia , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Adolescente , Anticorpos Antivirais/biossíntese , Criança , Pré-Escolar , Estudos de Coortes , Método Duplo-Cego , Europa (Continente) , Feminino , Soropositividade para HIV , Testes de Inibição da Hemaglutinação , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/virologia , Masculino , Filipinas , Segurança , Estados Unidos , Vacinação , Vacinas de Produtos InativadosRESUMO
BACKGROUND: Protection against dengue requires immunity against all 4 serotypes of dengue virus (DENV). Experimental challenge may be useful in evaluating vaccine-induced immunity. METHODS: Ten subjects previously vaccinated with a live attenuated tetravalent dengue vaccine (TDV) and 4 DENV-naive control subjects were challenged by subcutaneous inoculation of either 10(3) plaque-forming units (PFU) of DENV-1 or 10(5) PFU of DENV-3. Two additional subjects who did not develop DENV-3 neutralizing antibody (NAb) from TDV were revaccinated with 10(4) PFU of live attenuated DENV-3 vaccine to evaluate memory response. RESULTS: All 5 TDV recipients were protected against DENV-1 challenge. Of the 5 TDV recipients challenged with DENV-3, 2 were protected. All DENV-3-challenge subjects who developed viremia also developed elevated liver enzyme levels, and 2 had values that were >10 times greater than normal. Of the 2 subjects revaccinated with DENV-3 vaccine, 1 showed a secondary response to DENV-2, while neither showed such response to DENV-3. All 4 control subjects developed dengue fever from challenge. Protection was associated with presence of NAb, although 1 subject was protected despite a lack of measurable NAb at the time of DENV-1 challenge. CONCLUSIONS: Vaccination with TDV induced variable protection against subcutaneous challenge. DENV-3 experimental challenge was associated with transient but marked elevations of transaminases.
Assuntos
Vacinas contra Dengue/administração & dosagem , Vacinas contra Dengue/imunologia , Vírus da Dengue/imunologia , Vírus da Dengue/patogenicidade , Dengue/prevenção & controle , Adulto , Análise Química do Sangue , Dengue/patologia , Feminino , Humanos , Fígado/enzimologia , Testes de Função Hepática , Masculino , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Viremia/patologia , Viremia/prevenção & controle , Adulto JovemRESUMO
BACKGROUND: Mismatch between circulating influenza B viruses (Yamagata and Victoria lineages) and vaccine strains occurs frequently. METHODS: In a randomized controlled trial, immunogenicity and safety of an inactivated quadrivalent influenza vaccine candidate (QIV) versus trivalent inactivated influenza vaccine (TIV)-Victoria(Vic) and TIV-Yamagata(Yam) in children 3-17 years of age was evaluated. In an open-label study arm, QIV only was assessed in children 6-35 months of age. RESULTS: A total of 3094 children (932 QIV, 929 TIV-Vic, 932 TIV-Yam, and 301 QIV only) were vaccinated. QIV was noninferior to the TIVs for shared strains (A/H3N2 and A/H1N1) based on hemagglutination-inhibition (HI) antibodies 28 days after last vaccination, and superior for the unique B strains Victoria and Yamagata (geometric mean titer ratios 2.61, 3.78; seroconversion rate differences 33.96%, 44.63%). Among children in the randomized trial, adverse event rates were similar except for injection site pain (dose 1: 65.4% QIV, 54.6% TIV-Vic, 55.7% TIV-Yam). CONCLUSION: QIV elicited superior HI responses to the added B strains compared to TIV controls, potentially improving its effectiveness against influenza B. HI responses were similar between QIV and TIV controls for the shared strains. QIV had an acceptable safety profile relative to TIVs. CLINICAL TRIALS REGISTRATION: NCT01198756.
Assuntos
Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Adolescente , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Lactente , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/administração & dosagem , Masculino , Dor/epidemiologia , Dor/patologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , VitóriaRESUMO
BACKGROUND: The development of a universal influenza virus vaccine, to protect against both seasonal and pandemic influenza A viruses, is a long-standing public health goal. The conserved stalk domain of haemagglutinin (HA) is a promising vaccine target. However, the stalk is immunosubdominant. As such, innovative approaches are required to elicit robust immunity against this domain. In a previously reported observer-blind, randomised placebo-controlled phase I trial (NCT03300050), immunisation regimens using chimeric HA (cHA)-based immunogens formulated as inactivated influenza vaccines (IIV) -/+ AS03 adjuvant, or live attenuated influenza vaccines (LAIV), elicited durable HA stalk-specific antibodies with broad reactivity. In this study, we sought to determine if these vaccines could also boost T cell responses against HA stalk, and nucleoprotein (NP). METHODS: We measured interferon-γ (IFN-γ) responses by Enzyme-Linked ImmunoSpot (ELISpot) assay at baseline, seven days post-prime, pre-boost and seven days post-boost following heterologous prime:boost regimens of LAIV and/or adjuvanted/unadjuvanted IIV-cHA vaccines. FINDINGS: Our findings demonstrate that immunisation with adjuvanted cHA-based IIVs boost HA stalk-specific and NP-specific T cell responses in humans. To date, it has been unclear if HA stalk-specific T cells can be boosted in humans by HA-stalk focused universal vaccines. Therefore, our study will provide valuable insights for the design of future studies to determine the precise role of HA stalk-specific T cells in broad protection. INTERPRETATION: Considering that cHA-based vaccines also elicit stalk-specific antibodies, these data support the further clinical advancement of cHA-based universal influenza vaccine candidates. FUNDING: This study was funded in part by the Bill and Melinda Gates Foundation (BMGF).
Assuntos
Anticorpos Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Imunidade Celular , Vacinas contra Influenza , Influenza Humana , Humanos , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/imunologia , Anticorpos Antivirais/imunologia , Feminino , Adulto , Masculino , Linfócitos T/imunologia , Imunização Secundária , Interferon gama/metabolismo , Nucleoproteínas/imunologia , Adulto Jovem , Vírus da Influenza A/imunologiaRESUMO
INTRODUCTION: Recombinant acellular pertussis (ap) vaccines containing genetically inactivated pertussis toxin (PTgen) and filamentous hemagglutinin (FHA) with or without tetanus (TT) and diphtheria (DT) vaccines (Td) were found safe and immunogenic in non-pregnant and pregnant women. We report here maternal antibody transfer and safety data in mothers and neonates. METHODS: This is the follow up of a phase 2 trial in 2019 among 400 pregnant women who randomly received one dose of recombinant pertussis-only vaccine containing 1 µg PTgen and 1 µg FHA (ap1gen), or Td combined with ap1gen (Tdap1gen), or with 2 µg PTgen and 5 µg FHA (Tdap2gen), or with 5 µg PTgen and 5 µg FHA (TdaP5gen, Boostagen®, BioNet, Thailand) or chemically-inactivated acellular pertussis comparator (Tdap8chem, Boostrix™, GSK, Belgium), either in the second or third trimester of gestation. IgG against PT, FHA, TT and DT were assessed by ELISA, PT-neutralizing antibodies (PTNA) by Chinese Hamster Ovary cell assay and safety outcomes at delivery in mothers and at birth. RESULTS: Anti-PT and anti-FHA geometric mean concentration (GMC) ratio between infants at birth and mothers at delivery was above 1 in all groups. PT GMC in infants at birth were ≥30 IU/mL in all groups with the highest titers in infants found in TdaP5gen group at birth (118.8 [95% CI 93.9-150.4]). At 2 months, PT GMC ratio to Tdap8chem (98.75% CI) was significantly higher for TdaP5gen (2.6 [1.7-4.0]) and comparable for other recombinant vaccines. No difference in PTNA titers at birth was observed between all groups nor between time of vaccination. Adverse events were comparable in all vaccine groups. CONCLUSIONS: BioNet licensed (TdaP5gen and Tdap2gen) and candidate vaccines (Tdap1gen and ap1gen) when given to pregnant women in the second or third trimester of gestation are safe and have induced passive pertussis immunity to infants.
Assuntos
Vacinas contra Difteria, Tétano e Coqueluche Acelular , Tétano , Coqueluche , Lactente , Recém-Nascido , Cricetinae , Animais , Humanos , Feminino , Gravidez , Coqueluche/prevenção & controle , Células CHO , Anticorpos Antibacterianos , Cricetulus , Vacina contra Coqueluche , Vacinação , Vacinas Sintéticas , Toxoide Tetânico , Anticorpos Neutralizantes , Mães , Período Pós-PartoRESUMO
BACKGROUND: Two antigenically distinct influenza B lineages have co-circulated since the 1980s, yet inactivated trivalent influenza vaccines (TIVs) include strains of influenza A/H1N1, A/H3N2, and only one influenza B from either the Victoria or Yamagata lineage. This means that exposure to B-lineage viruses mismatched to the TIV is frequent, reducing vaccine protection. Formulations including both influenza B lineages could improve protection against circulating influenza B viruses. We assessed a candidate inactivated quadrivalent influenza vaccine (QIV) containing both B lineages versus TIV in adults in stable health. METHODS: A total of 4659 adults were randomized 5:5:5:5:3 to receive one dose of QIV (one of three lots) or a TIV containing either a B/Victoria or B/Yamagata strain. Hemagglutination-inhibition assays were performed pre-vaccination and 21-days after vaccination. Lot-to-lot consistency of QIV was assessed based on geometric mean titers (GMT). For QIV versus TIV, non-inferiority against the three shared strains was demonstrated if the 95% confidence interval (CI) upper limit for the GMT ratio was ≤1.5 and for the seroconversion difference was ≤10.0%; superiority of QIV versus TIV for the alternate B lineage was demonstrated if the 95% CI lower limit for the GMT ratio was > 1.0 and for the seroconversion difference was > 0%. Reactogenicity and safety profile of each vaccine were assessed. Clinicaltrials.gov: NCT01204671. RESULTS: Consistent immunogenicity was demonstrated for the three QIV lots. QIV was non-inferior to TIV for the shared vaccine strains, and was superior for the added alternate-lineage B strains. QIV elicited robust immune responses against all four vaccine strains; the seroconversion rates were 77.5% (A/H1N1), 71.5% (A/H3N2), 58.1% (B/Victoria), and 61.7% (B/Yamagata). The reactogenicity and safety profile of QIV was consistent with TIV. CONCLUSIONS: QIV provided superior immunogenicity for the additional B strain compared with TIV, without interfering with antibody responses to the three shared antigens. The additional antigen did not appear to alter the safety profile of QIV compared with TIV. This suggests that the candidate QIV is a viable alternative to TIV for use in adults, and could potentially improve protection against influenza B. TRIAL REGISTRATION: Clinical Trials.gov: NCT01204671/114269.
Assuntos
Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adulto JovemRESUMO
INTRODUCTION: Despite a decrease in infections caused by Bordetella pertussis due to COVID-19 pandemic, booster vaccination of pregnant women is still recommended to protect newborns. Highly immunogenic vaccines containing genetically inactivated pertussis toxin (PTgen) and filamentous hemagglutinin (FHA) may generate comparable anti-PT antibody concentrations, even at lower doses, to chemically inactivated acellular pertussis vaccines (Tdapchem) shown effective for maternal immunization. METHODS: This phase 2 randomized, observer-blind, active-controlled non-inferiority trial was conducted in healthy Thai pregnant women randomly assigned to receive one dose of low-dose recombinant pertussis-only vaccine containing 1 µg PTgen and 1 µg FHA (ap1gen), or tetanus, reduced-dose diphtheria combined with ap1gen (Tdap1gen), or combined with 2 µg PTgen and 5 µg FHA (Tdap2gen), or with 5 µg PTgen and 5 µg FHA (TdaP5gen, Boostagen®) or comparator containing 8 µg of chemically inactivated pertussis toxoid, 8 µg FHA, and 2.5 µg pertactin (Boostrix™, Tdap8chem). Blood was collected at Day 0 and Day 28 post-vaccination. The non-inferiority of the study vaccines was assessed based on anti-PT IgG antibody levels on Day 28 pooled with results from a similarly structured previous trial in non-pregnant women. RESULTS: 400 healthy pregnant women received one dose of vaccine. Combined with data from 250 non-pregnant women, all study vaccines containing PTgen were non-inferior to comparator vaccine (Tdap8chem). Both ap1gen and TdaP5gen vaccines could be considered to have superior immunogenicity to Tdap8chem. Local and systemic solicited reactions were similar among all vaccine groups. CONCLUSIONS: Vaccine formulations containing PTgen were safe and immunogenic in pregnant women. The ap1gen vaccine, with the lowest cost and reactogenicity, may be suitable for use in pregnant women when diphtheria and tetanus toxoids are not needed. This study is registered in the Thai Clinical Trial Registry (www. CLINICALTRIALS: in.th), number TCTR20180725004.
Assuntos
COVID-19 , Vacinas contra Difteria, Tétano e Coqueluche Acelular , Difteria , Tétano , Coqueluche , Recém-Nascido , Humanos , Feminino , Toxina Pertussis/genética , Pandemias , Vacina contra Coqueluche , Imunização Secundária/métodos , Toxoide Tetânico , Vacinas Sintéticas , Anticorpos Antibacterianos , Vacina contra Difteria, Tétano e CoquelucheRESUMO
BACKGROUND: Live, multivalent vaccines have historically exhibited interference in humans; live dengue virus (DENV) vaccines have proven no exception. METHODS: To characterize interactions between DENV serotypes in a tetravalent live-attenuated virus vaccine candidate, we analyzed data from a factorial clinical trial in which all combinations of high- and low-dose DENV serotypes were combined in 16 live-attenuated tetravalent vaccine formulations (N = 64) and administered to flavivirus-naive adult volunteers. Regression models considered the outcomes of reactogenicity and seroconversion, controlling for all serotype doses simultaneously. Additionally, results were compared against earlier evaluations of the same viruses administered as monovalent formulations. RESULTS: DENV-1 was immunologically dominant in both monovalent and tetravalent formulations. In tetravalent formulations, DENV-1 and DENV-2 antagonized each other, with a high dose of one decreasing seroconversion to the other. However, high-dose DENV-1 significantly increased seroconversion against 3 or more serotypes, increasing seroconversion to DENV-1, DENV-3, and DENV-4. The highest reactogenicity occurred when DENV-1 was at high dose and all others were low; reactogenicity decreased with the incorporation of other high-dose serotypes. CONCLUSIONS: Interference and facilitation occurred between serotypes in the live vaccine candidate evaluated. These analyses suggest that it may be possible to exploit facilitation to increase overall seroconversion.
Assuntos
Vacinas contra Dengue/administração & dosagem , Vírus da Dengue/classificação , Anticorpos Antivirais/sangue , Ensaios Clínicos como Assunto , Vacinas contra Dengue/efeitos adversos , Vacinas contra Dengue/imunologia , Relação Dose-Resposta Imunológica , Humanos , Modelos Logísticos , Sorotipagem , Vacinação/efeitos adversosRESUMO
BACKGROUND: Decisions regarding the evaluation of children with influenza infection rely on the likelihood of severe disease. The role of early vital signs as predictors of severe influenza infection in children is not well known. Our objectives were to determine the value of vital signs in predicting hospitalization/recurrent emergency department (ED) visits due to influenza infection in children. METHODS: We conducted a prospective study of children aged 6 months to 8 years of age with influenza like illness evaluated at an ED/UC from 2016-2018. All children underwent influenza testing by PCR. We collected heart rate, respiratory rate and temperature, and converted heart rate (HR) and respiratory rate (RR) to z-scores by age. HR z scores were further adjusted for temperature. Our primary outcome was hospitalization/recurrent ED visits within 72 hours. Vital sign predictors with p< 0.2 and other clinical covariates were entered into a multivariable logistic regression model to determine odds ratios (OR) and 95% CI; model performance was assessed using the Brier score and discriminative ability with the C statistic. RESULTS: Among 1478 children, 411 (27.8%) were positive for influenza, of which 42 (10.2%) were hospitalized or had a recurrent ED visit. In multivariable analyses, adjusting for age, high-risk medical condition and school/daycare attendance, higher adjusted respiratory rate (OR 2.09, 95%CI 1.21-3.61, p = 0.0085) was a significant predictor of influenza hospitalization/recurrent ED visits. CONCLUSIONS: Higher respiratory rate adjusted for age was the most useful vital sign predictor of severity among young children with PCR-confirmed influenza.
Assuntos
Influenza Humana , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Hospitalização , Humanos , Lactente , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Estudos Prospectivos , Sinais Vitais/fisiologiaRESUMO
BACKGROUND: Data from a randomized controlled efficacy trial of an inactivated quadrivalent influenza vaccine in children 6-35 months of age were used to determine whether hemagglutination inhibition (HI) antibody titer against A/H1N1 and A/H3N2 is a statistical correlate of protection (CoP) for the risk of reverse-transcription polymerase chain reaction (RT-PCR)-confirmed influenza associated with the corresponding strain. METHODS: The Prentice criteria were used to statistically validate strain-specific HI antibody titer as a CoP. The probability of protection was identified using the Dunning model corresponding to a prespecified probability of protection at an individual level. The group-level protective threshold was identified using the Siber approach, leading to unbiased predicted vaccine efficacy (VE). A case-cohort subsample was used for this exploratory analysis. RESULTS: Prentice criteria confirmed that HI titer is a statistical CoP for RT-PCR-confirmed influenza. The Dunning model predicted a probability of protection of 49.7% against A/H1N1 influenza and 54.7% against A/H3N2 influenza at an HI antibody titer of 1:40 for the corresponding strain. Higher titers of 1:320 were associated with >80% probability of protection. The Siber method predicted VE of 61.0% at a threshold of 1:80 for A/H1N1 and 46.6% at 1:113 for A/H3N2. CONCLUSIONS: The study validated HI antibody titer as a statistical CoP, by demonstrating that HI titer is correlated with clinical protection against RT-PCR-confirmed influenza associated with the corresponding influenza strain and is predictive of VE in children 6-35 months of age. CLINICAL TRIALS REGISTRATION: NCT01439360.
RESUMO
BACKGROUND: A phase 2 randomized-controlled safety and immunogenicity trial evaluating different doses of recombinant acellular pertussis vaccine containing genetically-inactivated pertussis toxin (PTgen) was conducted in women of childbearing age in Thailand to identify formulations to advance to a trial in pregnant women. METHODS: A total of 250 women were randomized 1:1:1:1:1 to receive one dose of one of three investigational vaccines including low-dose recombinant pertussis-only vaccine containing 1 µg PTgen and 1 µg FHA (ap1gen), tetanus, reduced-dose diphtheria (Td) combined to ap1gen (Tdap1gen) or combined to recombinant pertussis containing 2 µg PTgen and 5 µg FHA (Tdap2gen), or one dose of licensed recombinant TdaP vaccine containing 5 µg PTgen and 5 µg FHA (Boostagen®, TdaP5gen) or licensed Tdap vaccine containing 8 µg of chemically inactivated pertussis toxoid (PTchem), 8 µg FHA, and 2.5 µg pertactin (PRN) (BoostrixTM, Tdap8chem). Serum Immunoglobulin G (IgG) antibodies against vaccine antigens were measured before and 28 days after vaccination by ELISA. To advance to a trial in pregnant women, formulations had to induce a PT-IgG seroresponse rate with a 95% confidence interval (95% CI) lower limit of ≥ 50%. RESULTS: Between 5 and 22 July 2018, a total of 250 women with median age of 31 years were enrolled. Post-vaccination PT-IgG seroresponse rates were 92% (95% CI 81-98) for ap1gen, 88% (95% CI 76-95) for Tdap1gen, 80% (95% CI 66-90) for Tdap2gen, 94% (95% CI 83-99) for TdaP5gen, and 78% (95% CI 64-88) for Tdap8chem. Frequencies of injection site and systemic reactions were comparable between the groups. No serious adverse events were reported during the 28-day post-vaccination period. CONCLUSIONS: All recombinant acellular pertussis vaccines were safe and immunogenic in women of childbearing age, and all met pre-defined immunogenicity criteria to advance to a trial in pregnant women. CLINICAL TRIAL REGISTRATION: Thai Clinical Trial Registry, TCTR20180321004.