RESUMO
BACKGROUND: Takeda's live attenuated tetravalent dengue vaccine candidate (TAK-003) is under evaluation in a long-term clinical trial across 8 dengue-endemic countries. Previously, we have reported its efficacy and safety in both seronegative and seropositive participants and that its performance varies by serotype, with some decline in efficacy from first to second year postvaccination. This exploratory analysis provides an update with cumulative and third-year data. METHODS: Healthy 4-16 year olds (nâ =â 20099) were randomized 2:1 to receive TAK-003 or placebo (0, 3 month schedule). The protocol included baseline serostatus testing of all participants and detection of all symptomatic dengue throughout the trial with a serotype specific reverse transcriptase-polymerase chain reaction. RESULTS: Cumulative efficacy after 3 years was 62.0% (95% confidence interval, 56.6-66.7) against virologically confirmed dengue (VCD) and 83.6% (76.8-88.4) against hospitalized VCD. Efficacy was 54.3% (41.9-64.1) against VCD and 77.1% (58.6-87.3) against hospitalized VCD in baseline seronegatives, and 65.0% (58.9-70.1) against VCD and 86.0% (78.4-91.0) against hospitalized VCD in baseline seropositives. Efficacy against VCD during the third year declined to 44.7% (32.5-54.7), whereas efficacy against hospitalized VCD was sustained at 70.8% (49.6-83.0). Rates of serious adverse events were 2.9% in TAK-003 group and 3.5% in placebo group during the ongoing long-term follow-up (ie, second half of the 3 years following vaccination), but none were related. No important safety risks were identified. CONCLUSIONS: TAK-003 was efficacious against symptomatic dengue over 3 years. Efficacy declined over time but remained robust against hospitalized dengue. A booster dose evaluation is planned.
Assuntos
Vacinas contra Dengue , Vírus da Dengue , Dengue , Anticorpos Antivirais , Humanos , Sorogrupo , Resultado do Tratamento , Vacinas Atenuadas/efeitos adversos , Vacinas CombinadasRESUMO
BACKGROUND: Takeda's dengue vaccine is under evaluation in an ongoing phase 3 efficacy study; we present a 2-year update. METHODS: Children (20 099, 4-16 years old) were randomized to receive 2 doses of TAK-003 or placebo 3 months apart and are under surveillance to detect dengue by serotype-specific RT-PCR. RESULTS: Cumulative efficacy against dengue approximately 27 months since first dose was 72.7% (95% confidence interval [CI], 67.1%-77.3%), including 67.0% (95% CI, 53.6%-76.5%) in dengue-naive and 89.2% (95% CI, 82.4%-93.3%) against hospitalized dengue. In the second year, decline in efficacy was observed (56.2%; 95% CI, 42.3%-66.8%) with the largest decline in 4-5 year olds (24.5%; 95% CI, -34.2% to 57.5%); efficacy was 60.6% (95% CI, 43.8%-72.4%) in 6-11 year and 71.2% (95% CI, 41.0%-85.9%) in 12-16 year age groups. As TAK-003 efficacy varies by serotype, changes in serotype dominance partially contributed to efficacy differences in year-by-year analysis. No related serious adverse events occurred during the second year. CONCLUSIONS: TAK-003 demonstrated continued benefit independent of baseline serostatus in reducing dengue with some decline in efficacy during the second year. Three-year data will be important to see if efficacy stabilizes or declines further.Clinical Trials Registration. NCT02747927.Takeda's tetravalent dengue vaccine (TAK-003) continued to demonstrate benefit in reducing dengue independent of baseline serostatus up to 2 years after completing vaccination with some decline in efficacy during the second year in 4-16 year olds in dengue-endemic countries.
Assuntos
Vacinas contra Dengue , Vírus da Dengue , Dengue , Adolescente , Anticorpos Neutralizantes , Anticorpos Antivirais , Criança , Pré-Escolar , Vírus da Dengue/genética , Método Duplo-Cego , Humanos , Vacinação , Vacinas AtenuadasRESUMO
OBJECTIVE: To describe the immunogenicity and safety of a tetravalent dengue vaccine (TAK-003) in healthy adolescents living in Mexico City, an area considered non-endemic for dengue (NCT03341637). METHODS: Participants aged 12-17 years were randomized 3:1 to receive two doses (Month 0 and Month 3) of TAK-003 or placebo. Immunogenicity was assessed by microneutralization assay of dengue neutralizing antibodies at baseline, Months 4 and 9. Solicited and unsolicited adverse events (AEs) were recorded after each vaccination. Serious (SAEs) and medically-attended AEs (MAAEs) were recorded throughout the study. RESULTS: 400 adolescents were enrolled, 391 (97.8%) completed the study. Thirty-six (9%) were baseline seropositive to ≥1 serotypes (reciprocal titer ≥10). Geometric mean titers (GMTs) in baseline seronegative TAK-003 recipients were 328, 1743, 120, and 143 at Month 4, and 135, 741, 46, and 38 at Month 9 against DENV-1, -2, -3, and -4, respectively. Placebo GMTs remained <10. Tetravalent seropositivity rates in vaccine recipients were 99.6% and 85.8% at Months 4 and 9, respectively. One MAAE in each group was considered treatment-related (TAK-003: injection-site erythema, and placebo: pharyngitis). CONCLUSION: TAK-003 was immunogenic against all four serotypes and was well tolerated in dengue-naïve adolescents living in Mexico City.
RESUMO
[ABSTRACT]. Objective. To describe the immunogenicity and safety of a tetravalent dengue vaccine (TAK-003) in healthy adolescents living in Mexico City, an area considered non-endemic for dengue (NCT03341637). Methods. Participants aged 12–17 years were randomized 3:1 to receive two doses (Month 0 and Month 3) of TAK-003 or placebo. Immunogenicity was assessed by microneutralization assay of dengue neutralizing antibodies at baseline, Months 4 and 9. Solicited and unsolicited adverse events (AEs) were recorded after each vaccination. Serious (SAEs) and medically-attended AEs (MAAEs) were recorded throughout the study. Results. 400 adolescents were enrolled, 391 (97.8%) completed the study. Thirty-six (9%) were baseline seropositive to ≥1 serotypes (reciprocal titer ≥10). Geometric mean titers (GMTs) in baseline seronegative TAK-003 recipients were 328, 1743, 120, and 143 at Month 4, and 135, 741, 46, and 38 at Month 9 against DENV-1, -2, -3, and -4, respectively. Placebo GMTs remained <10. Tetravalent seropositivity rates in vaccine recipients were 99.6% and 85.8% at Months 4 and 9, respectively. One MAAE in each group was considered treatment-related (TAK-003: injection-site erythema, and placebo: pharyngitis). Conclusion. TAK-003 was immunogenic against all four serotypes and was well tolerated in dengue-naïve adolescents living in Mexico City.
[RESUMEN]. Objetivo. Describir la inmunogenicidad y la seguridad de una vacuna tetravalente contra el dengue (TAK-003) en adolescentes sanos residentes en Ciudad de México, considerada un área no endémica de dengue (NCT03341637). Métodos. Se asignó de manera aleatoria a un grupo de participantes de 12 a 17 años en una proporción 3:1 para que recibieran dos dosis (en el mes 0 y en el mes 3) de la vacuna TAK-003 o de un placebo. Se evaluó la inmunogenicidad mediante un análisis de microneutralización de anticuerpos neutralizantes del virus del dengue al inicio del estudio y en los meses 4 y 9. Se registraron los eventos adversos de notificación solicitada y los referidos por iniciativa propia después de cada vacunación. A lo largo del estudio se registraron los eventos adversos graves y los que requirieron atención médica. Resultados. Participaron 400 adolescentes y 391 (97,8%) finalizaron el estudio. 36 adolescentes (9%) fueron seropositivos a ≥1 serotipos (título recíproco ≥10) al inicio del estudio. La media geométrica de los títulos en las personas seronegativas vacunadas con TAK-003 al inicio del estudio fue de 328, 1743, 120 y 143 en el mes 4 y 135, 741, 46 y 38 en el mes 9 en relación con DENV-1, -2, -3 y -4, respectivamente. La media geométrica de los títulos de las personas que recibieron un placebo se mantuvo en <10. Las tasas de seropositividad tetravalente en los vacunados fueron 99,6% y 85,8% a los meses 4 y 9, respectivamente. Se consideró relacionado con el tratamiento un evento adverso con atención médica que tuvo lugar en cada grupo (TAK-003: eritema en el lugar de la inyección; placebo: faringitis). Conclusiones. TAK-003 fue inmunogénica ante los cuatro serotipos y bien tolerada en los adolescentes sin exposición previa al dengue que vivían en Ciudad de México.
[RESUMO]. Objetivo. Descrever a imunogenicidade e a segurança de uma vacina tetravalente contra dengue (TAK-003) em adolescentes saudáveis residentes da Cidade do México, área considerada não endêmica para dengue (ClinicalTrials.gov: NCT03341637). Métodos. Participantes com idade entre 12 e 17 anos foram randomizados a uma proporção de 3:1 para receber duas doses da vacina TAK-003 ou placebo (no mês 0 e no mês 3). A imunogenicidade foi avaliada pelos títulos de anticorpos neutralizantes contra dengue determinados em ensaio de microneutralização ao início do estudo, no mês 4 e no mês 9. A ocorrência de eventos adversos solicitados ou espontâneos foi registrada após cada rodada de vacinação. Eventos adversos graves e eventos adversos que exigiram atendimento médico foram monitorados ao longo de todo o estudo. Resultados. De 400 adolescentes incluídos na amostra estudada, 391 (97,8%) completaram o estudo. Trinta e seis (9%) apresentaram positividade basal a um ou mais sorotipos virais da dengue (título recíproco ≥10). A média geométrica dos títulos de anticorpos nos vacinados com TAK-003 que eram soronegativos ao início do estudo foi de 328, 1743, 120 e 143 no mês 4 e 135, 741, 46 e 38 no mês 9, contra os sorotipos virais DENV-1, DENV-2, DENV-3 e DENV-4, respectivamente. A média geométrica dos títulos de anticorpos no grupo placebo se manteve abaixo de 10. A taxa de soropositividade tetravalente nos vacinados foi de 99,6% no mês 4 e 85,8% no mês 9. Um único evento adverso que exigiu atendimento médico em cada grupo foi considerado relacionado ao tratamento (eritema no local de aplicação no grupo TAK-003 e faringite no grupo placebo). Conclusão. A vacina TAK-003 demonstrou ser imunogênica contra os quatro sorotipos virais da dengue e foi bem tolerada em adolescentes residentes da Cidade do México sem história pregressa de infecção pela dengue.
Assuntos
Vacinas , Adolescente , Imunogenicidade da Vacina , Segurança , Dengue , México , Vacinas , Adolescente , Imunogenicidade da Vacina , Segurança , México , Vacinas , Imunogenicidade da Vacina , SegurançaRESUMO
BACKGROUND: A substantial unmet need remains for safe and effective vaccines against dengue virus disease, particularly for individuals who are dengue-naive and those younger than 9 years. We aimed to assess the efficacy, safety, and immunogenicity of a live attenuated tetravalent dengue vaccine (TAK-003) in healthy children aged 4-16 years. METHODS: We present data up to 18 months post-vaccination from an ongoing phase 3, randomised, double-blind trial of TAK-003 in endemic regions of Asia and Latin America (26 medical and research centres across Brazil, Colombia, Dominican Republic, Nicaragua, Panama, Philippines, Sri Lanka, and Thailand). Healthy children aged 4-16 years were randomly assigned 2:1 (stratified by age and region) to receive two doses of TAK-003 or two doses of placebo, 3 months apart. Investigators, participants and their parents or guardians, and sponsor representatives advising on trial conduct were masked to trial group assignments. Participants presenting with febrile illness were tested for virologically confirmed dengue (VCD) by serotype-specific RT-PCR. In timeframes beginning 30 days post-second dose, the primary endpoint (overall vaccine efficacy) was assessed in the first 11 months, and the secondary endpoints (efficacy by baseline serostatus, serotype, hospitalised dengue, and severe dengue) in the first 17 months. This study is registered with ClinicalTrials.gov, NCT02747927. FINDINGS: 20â099 participants were randomly assigned and vaccinated between Sept 7, 2016, and Aug 18, 2017; 19â021 (94·6%) were included in the per protocol analysis, and 20â071 (99·9%) in the safety set. The primary endpoint was achieved with an overall vaccine efficacy of 80·2% (95% CI 73·3 to 85·3; 61 cases of VCD in the TAK-003 group vs 149 cases of VCD in the placebo group). In the secondary endpoint assessment timeframe, an overall vaccine efficacy of 73·3% (95% CI 66·5 to 78·8) was observed. Analysis of secondary endpoints showed efficacies of 76·1% (95% CI 68·5 to 81·9) in individuals who were seropositive at baseline, 66·2% (49·1 to 77·5) in individuals who were seronegative at baseline, 90·4% (82·6 to 94·7) against hospitalised dengue, and 85·9% (31·9 to 97·1) against dengue haemorrhagic fever. Efficacy varied by individual serotypes (DENV 1, 69·8% [95% CI 54·8 to 79·9]; DENV 2, 95·1% [89·9 to 97·6]; DENV 3, 48·9% [27·2 to 64·1]; DENV 4, 51·0% [-69·4 to 85·8]). Cumulative rates of serious adverse events were similar in TAK-003 (4·0%) and placebo (4·8%) recipients, and were consistent with expected medical disorders in the study population. Infection was the most frequent reason leading to serious adverse events. 20 participants (<0·1% of the safety set) were withdrawn from the trial due to 21 adverse events by the end of part two; 14 of these participants received TAK-003 and six received placebo. INTERPRETATION: TAK-003 was well tolerated and efficacious against symptomatic dengue in children regardless of serostatus before immunisation. Vaccine efficacy varied by serotype, warranting continued follow-up to assess longer-term vaccine performance. FUNDING: Takeda Vaccines.
Assuntos
Vacinas contra Dengue/efeitos adversos , Vírus da Dengue/imunologia , Dengue/prevenção & controle , Vacinação/efeitos adversos , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Colômbia/epidemiologia , Vacinas contra Dengue/uso terapêutico , Vírus da Dengue/genética , República Dominicana/epidemiologia , Método Duplo-Cego , Hospitalização/estatística & dados numéricos , Humanos , Nicarágua/epidemiologia , Panamá/epidemiologia , Filipinas/epidemiologia , Placebos/administração & dosagem , Sorogrupo , Índice de Gravidade de Doença , Sri Lanka/epidemiologia , Tailândia/epidemiologia , Resultado do Tratamento , Vacinação/métodosRESUMO
BACKGROUND: An unmet clinical need remains for an effective tetravalent dengue vaccine suitable for all age groups, regardless of serostatus. We assessed the immunogenicity and safety of three different dose schedules of a tetravalent dengue vaccine (TAK-003) over a 48-month period in children living in dengue-endemic countries. METHODS: We did a large, phase 2, double-blind, placebo-controlled trial at three sites in the Dominican Republic, Panama, and the Philippines. Healthy participants aged 2-17 years were randomly assigned 1:2:5:1 using an interactive web response system with stratification by age to receive either a two-dose primary series (days 1 and 91), one primary dose (day 1), one primary dose plus booster (days 1 and 365), or placebo. Participants and relevant study personnel were masked to the random assignment until completion of the study at month 48. To maintain masking, TAK-003 recipients were administered placebo doses when appropriate. The primary objective was assessment of neutralising geometric mean titres for each serotype to month 48 assessed in the per-protocol immunogenicity subset. Secondary safety endpoints included proportions of participants with serious adverse events and symptomatic virologically confirmed dengue. This study is registered with ClinicalTrials.gov, NCT02302066. FINDINGS: Between Dec 5, 2014, and Feb 13, 2015, 1800 children were randomly assigned to the following groups: two-dose primary series (n=201), one primary dose (n=398), one primary dose plus 1-year booster (n=1002), and placebo (n=199). Of them, 1479 (82%) participants completed the 48-month study. Immunogenicity endpoints were assessed in 562 participants enrolled in the immunogenicity subset, of whom 509 were included in the per-protocol subset. At month 48, antibody titres remained elevated in all TAK-003 groups compared with placebo, irrespective of baseline serostatus. At month 48, geometric mean titres were 378 (95% CI 226-632) in two-dose, 421 (285-622) in one-dose, 719 (538-960) in one-dose plus 1-year booster, and 100 (50-201) in placebo recipients against DENV 1; 1052 (732-1511), 1319 (970-1794), 1200 (927-1553), and 208 (99-437) against DENV 2; 183 (113-298), 201 (135-298), 288 (211-392), and 71 (37-139) against DENV 3; and 152 (97-239), 164 (114-236), 219 (165-290), and 46 (26-82) against DENV 4; and tetravalent seropositivity rate was 89% (79-96), 86% (80-92), 97% (93-99), and 60% (47-72), respectively. Virologically confirmed dengue was recorded in 37 (2%) TAK-003 and 13 (7%) placebo participants, with a relative risk of 0·35 (0·19-0·65). No vaccine-related serious adverse events or severe dengue virus disease were reported. INTERPRETATION: TAK-003 elicited antibody responses against all four serotypes, which persisted to 48 months post-vaccination, regardless of baseline serostatus. No important safety risks were identified. We observed a long-term reduction in risk of symptomatic dengue virus disease in vaccinees. Results from this study provide a long-term safety database and support assessment of the vaccine in the ongoing phase 3 efficacy study. FUNDING: Takeda Vaccines.
Assuntos
Vacinas contra Dengue/efeitos adversos , Vírus da Dengue/imunologia , Dengue/prevenção & controle , Imunogenicidade da Vacina/imunologia , Adolescente , Criança , Pré-Escolar , Dengue/imunologia , Dengue/virologia , Vacinas contra Dengue/administração & dosagem , Vírus da Dengue/genética , República Dominicana/epidemiologia , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Imunização Secundária/métodos , Masculino , Panamá/epidemiologia , Filipinas/epidemiologia , Placebos/administração & dosagem , Segurança , Sorogrupo , Vacinação/métodosRESUMO
BACKGROUND: Diphtheria-tetanus-whole-cell pertussis (DTPw)-based combination vaccines are an attractive option to rapidly achieve high coverage and protection against other important pathogens, such as hepatitis B virus (HBV) and Haemophilus influenzae type B (Hib). To ensure adequate antigen supply, GlaxoSmithKline Biologicals has introduced a new DTPw antigen source and developed a new DTPw-HBV/Hib combination vaccine containing a reduced amount of Hib polyribosylribitol phosphate (PRP). This study was undertaken to compare the immunogenicity and reactogenicity of this new DTPw-HBV/Hib vaccine with a licensed DTPw-HBV/Hib vaccine (Tritanrix™-HBV/Hib). METHODS: This was a randomized, partially-blind, multicenter study in three countries in Latin America (Argentina, Chile and Nicaragua). Healthy children received either the new DTPw-HBV/Hib vaccine (1 of 3 lots; n = 439; double-blind) or Tritanrix™-HBV/Hib (n = 146; single-blind) co-administered with oral poliovirus vaccine (OPV) at 2, 4 and 6 months, with a booster dose at 18-24 months. RESULTS: One month after the end of the 3-dose primary vaccination course, the new DTPw-HBV/Hib vaccine was non-inferior to Tritanrix™-HBV/Hib in terms of seroprotection/vaccine response rates for all component antigens; ≥97.3% and ≥93.9% of subjects in the two groups, respectively, had seroprotective levels of antibodies against diphtheria, tetanus, hepatitis B and Hib and a vaccine response to the pertussis component. Persistence of antibodies against all vaccine antigens was comparable between groups, with marked increases in all antibody concentrations after booster administration in both groups. Both vaccines were generally well-tolerated as primary and booster doses. CONCLUSIONS: Results confirm the suitability of this new DTPw-HBV/Hib vaccine comprising antigens from a new source and a reduced PRP content for inclusion into routine childhood vaccination programs. TRIAL REGISTRATION: http://www.clinicaltrials.gov NCT00332566.