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BACKGROUND: We explored the impact of prior Yellow fever (YF) or Japanese encephalitis (JE) vaccination on the efficacy of Takeda's dengue vaccine candidate, TAK-003 (NCT02747927). METHODS: Children 4-16 years of age were randomized 2:1 to receive TAK-003 or placebo and were under active febrile surveillance. Symptomatic dengue was confirmed by serotype-specific RT-PCR. YF and JE vaccination history was recorded. RESULTS: Of the 20,071 children who received TAK-003 or placebo, 21.1% had a YF and 23.9% had a JE vaccination history at randomization. Fifty-seven months after vaccination, vaccine efficacy was 55.7% (95% CI, 39.7%-67.5%) in those with YF vaccination, 77.8% (70.8%-83.1%) for JE vaccination, and 53.5% (45.4%-60.4%) for no prior YF/JE vaccination. Regional differences in serotype distribution confound these results. The apparent higher vaccine efficacy in the JE vaccination subgroup could be largely explained by serotype-specific efficacy of TAK-003. Within 28 days of any vaccination, the proportions of participants with serious adverse events in the YF/JE prior vaccination population were comparable between the TAK-003 and placebo groups. CONCLUSIONS: The available data do not suggest a clinically relevant impact of prior JE or YF vaccination on TAK-003 performance. Overall, TAK-003 was well-tolerated and efficacious in different epidemiological settings.
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BACKGROUND: Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections in infants. This phase 1/2, observer-blind, randomized, controlled study assessed the safety and immunogenicity of an investigational chimpanzee-derived adenoviral vector RSV vaccine (ChAd155-RSV, expressing RSV F, N, and M2-1) in infants. METHODS: Healthy 6- to 7-month-olds were 1:1:1-randomized to receive 1 low ChAd155-RSV dose (1.5 × 1010 viral particles) followed by placebo (RSV_1D); 2 high ChAd155-RSV doses (5 × 1010 viral particles) (RSV_2D); or active comparator vaccines/placebo (comparator) on days 1 and 31. Follow-up lasted approximately 2 years. RESULTS: Two hundred one infants were vaccinated (RSV_1D: 65; RSV_2D: 71; comparator: 65); 159 were RSV-seronaive at baseline. Most solicited and unsolicited adverse events after ChAd155-RSV occurred at similar or lower rates than after active comparators. In infants who developed RSV infection, there was no evidence of vaccine-associated enhanced respiratory disease (VAERD). RSV-A neutralizing titers and RSV F-binding antibody concentrations were higher post-ChAd155-RSV than postcomparator at days 31, 61, and end of RSV season 1 (mean follow-up, 7 months). High-dose ChAd155-RSV induced stronger responses than low-dose, with further increases post-dose 2. CONCLUSIONS: ChAd155-RSV administered to 6- to 7-month-olds had a reactogenicity/safety profile like other childhood vaccines, showed no evidence of VAERD, and induced a humoral immune response. Clinical Trials Registration. NCT03636906.
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Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Humanos , Lactante , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vectores Genéticos , Inmunogenicidad Vacunal , Infecciones por Virus Sincitial Respiratorio/prevención & control , Virus Sincitial Respiratorio Humano/genéticaRESUMEN
BACKGROUND: Dengue is an increasing threat to global health. This exploratory analysis evaluated the immunogenicity, safety, and vaccine efficacy (VE) of a live-attenuated tetravalent dengue vaccine (TAK-003) in participants enrolled in the phase 3 DEN-301 trial (NCT02747927), stratified by baseline age (4-5 years; 6-11 years; or 12-16 years). METHODS: Participants were randomized 2:1 to receive 2 doses of TAK-003, administered 3 months apart, or placebo. Dengue serostatus was evaluated at enrolment. VE against virologically-confirmed dengue (VCD) and hospitalized VCD; immunogenicity (geometric mean titers; GMTs); and safety were evaluated per age group through â¼4 years post-vaccination. RESULTS: VE against VCD across serotypes was 43.5% (95% confidence interval: 25.3%, 57.3%) for 4-5 year-olds; 63.5% (56.9%, 69.1%) for 6-11 year-olds, and 67.7% (57.8%, 75.2%) for 12-16 year-olds. VE against hospitalized VCD was 63.8% (21.1%, 83.4%), 85.1% (77.1%, 90.3%), and 89.7% (77.9%, 95.2%), for the three age groups, respectively. GMTs remained elevated against all four serotypes for â¼4 years post-vaccination, with no evident differences across age groups. No clear differences in safety by age were identified. CONCLUSIONS: This exploratory analysis shows TAK-003 was efficacious in dengue prevention across age groups in children and adolescents 4-16 years of age living in dengue endemic areas. Relatively lower VE in 4-5 year-olds was potentially confounded by causative serotype distribution, small sample size, and VE by serotype, and should be considered in benefit-risk evaluations in this age group.
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BACKGROUND: Safe and effective respiratory syncytial virus (RSV) vaccines remain elusive. This was a phase I/II trial (NCT02927873) of ChAd155-RSV, an investigational chimpanzee adenovirus-RSV vaccine expressing 3 proteins (fusion, nucleoprotein, and M2-1), administered to 12-23-month-old RSV-seropositive children followed up for 2 years after vaccination. METHODS: Children were randomized to receive 2 doses of ChAd155-RSV or placebo (at a 1:1 ratio) (days 1 and 31). Doses escalated from 0.5 × 1010 (low dose [LD]) to 1.5 × 1010 (medium dose [MD]) to 5 × 1010 (high dose [HD]) viral particles after safety assessment. Study end points included anti-RSV-A neutralizing antibody (Nab) titers through year 1 and safety through year 2. RESULTS: Eighty-two participants were vaccinated, including 11, 14, and 18 in the RSV-LD, RSV-MD, and RSV-HD groups, respectively, and 39 in the placebo groups. Solicited adverse events were similar across groups, except for fever (more frequent with RSV-HD). Most fevers were mild (≤38.5°C). No vaccine-related serious adverse events or RSV-related hospitalizations were reported. There was a dose-dependent increase in RSV-A Nab titers in all groups after dose 1, without further increase after dose 2. RSV-A Nab titers remained higher than prevaccination levels at year 1. CONCLUSIONS: Three ChAd155-RSV dosages were found to be well tolerated. A dose-dependent immune response was observed after dose 1, with no observed booster effect after dose 2. Further investigation of ChAd155-RSV in RSV-seronegative children is warranted. CLINICAL TRIALS REGISTRATION: NCT02927873.
Respiratory syncytial virus (RSV) is among the main causes of bronchiolitis and pneumonia regularly leading to hospitalization in children. A safe and effective vaccine to prevent RSV infection in this age group has not yet been found, despite great efforts over several decades. This study tested a new candidate RSV vaccine, expressing 3 important pieces of the virus, in toddlers who already had a previous RSV infection. The vaccine was generally well tolerated. Vaccination triggered antibodies against RSV that were able to block the virus in laboratory tests and that persisted for 1 year.
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Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Humanos , Lactante , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Virus Sincitial Respiratorio Humano/genéticaRESUMEN
BACKGROUND: Primary intestinal immunity through viral replication of live oral vaccine is key to interrupt poliovirus transmission. We assessed viral fecal shedding from infants administered Sabin monovalent poliovirus type 2 vaccine (mOPV2) or low and high doses of 2 novel OPV2 (nOPV2) vaccine candidates. METHODS: In 2 randomized clinical trials in Panama, a control mOPV2 study (October 2015 to April 2016) and nOPV2 study (September 2018 to October 2019), 18-week-old infants vaccinated with bivalent oral poliovirus vaccine/inactivated poliovirus vaccine received 1 or 2 study vaccinations 28 days apart. Stools were assessed for poliovirus RNA by polymerase chain reaction (PCR) and live virus by culture for 28 days postvaccination. RESULTS: Shedding data were available from 621 initially reverse-transcription PCR-negative infants (91 mOPV2, 265 nOPV2-c1, 265 nOPV2-c2 recipients). Seven days after dose 1, 64.3% of mOPV2 recipients and 31.3%-48.5% of nOPV2 recipients across groups shed infectious type 2 virus. Respective rates 7 days after dose 2 decreased to 33.3% and 12.9%-22.7%, showing induction of intestinal immunity. Shedding of both nOPV2 candidates ceased at similar or faster rates than mOPV2. CONCLUSIONS: Viral shedding of either nOPV candidate was similar or decreased relative to mOPV2, and all vaccines showed indications that the vaccine virus was replicating sufficiently to induce primary intestinal mucosal immunity.
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Poliomielitis , Poliovirus , Anticuerpos Antivirales , Humanos , Lactante , Vacuna Antipolio de Virus Inactivados , Vacuna Antipolio Oral , Ensayos Clínicos Controlados Aleatorios como Asunto , Vacunas AtenuadasRESUMEN
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.
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Vacunas contra el Dengue , Virus del Dengue , Dengue , Adolescente , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Niño , Preescolar , Virus del Dengue/genética , Método Doble Ciego , Humanos , Vacunación , Vacunas AtenuadasRESUMEN
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.
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Vacunas contra el Dengue , Virus del Dengue , Dengue , Anticuerpos Antivirales , Humanos , Serogrupo , Resultado del Tratamiento , Vacunas Atenuadas/efectos adversos , Vacunas CombinadasRESUMEN
BACKGROUND: Continued emergence and spread of circulating vaccine-derived type 2 polioviruses and vaccine-associated paralytic poliomyelitis from Sabin oral poliovirus vaccines (OPVs) has stimulated development of two novel type 2 OPV candidates (OPV2-c1 and OPV2-c2) designed to have similar immunogenicity, improved genetic stability, and less potential to reacquire neurovirulence. We aimed to assess safety and immunogenicity of the two novel OPV candidates compared with a monovalent Sabin OPV in children and infants. METHODS: We did two single-centre, multi-site, partly-masked, randomised trials in healthy cohorts of children (aged 1-4 years) and infants (aged 18-22 weeks) in Panama: a control phase 4 study with monovalent Sabin OPV2 before global cessation of monovalent OPV2 use, and a phase 2 study with low and high doses of two novel OPV2 candidates. All participants received one OPV2 vaccination and subsets received two doses 28 days apart. Parents reported solicited and unsolicited adverse events. Type 2 poliovirus neutralising antibodies were measured at days 0, 7, 28, and 56, and stool viral shedding was assessed up to 28 days post-vaccination. Primary objectives were to assess safety in all participants and non-inferiority of novel OPV2 day 28 seroprotection versus monovalent OPV2 in infants (non-inferiority margin 10%). These studies were registered with ClinicalTrials.gov, NCT02521974 and NCT03554798. FINDINGS: The control study took place between Oct 23, 2015, and April 29, 2016, and the subsequent phase 2 study between Sept 19, 2018, and Sept 30, 2019. 150 children (50 in the control study and 100 of 129 assessed for eligibility in the novel OPV2 study) and 684 infants (110 of 114 assessed for eligibility in the control study and 574 of 684 assessed for eligibility in the novel OPV2 study) were enrolled and received at least one study vaccination. Vaccinations were safe and well tolerated with no causally associated serious adverse events or important medical events in any group. Solicited and unsolicited adverse events were overwhelmingly mild or moderate irrespective of vaccine or dose. Nearly all children were seroprotected at baseline, indicating high baseline immunity. In children, the seroprotection rate 28 days after one dose was 100% for monovalent OPV2 and both novel OPV2 candidates. In infants at day 28, 91 (94% [95% CI 87-98]) of 97 were seroprotected after receiving monovalent OPV2, 134 (94% [88-97]) of 143 after high-dose novel OPV2-c1, 122 (93% [87-97]) of 131 after low-dose novel OPV2-c1, 138 (95% [90-98]) of 146 after high-dose novel OPV2-c2, and 115 (91% [84-95]) of 127 after low-dose novel OPV2-c2. Non-inferiority was shown for low-dose and high-dose novel OPV2-c1 and high-dose novel OPV2-c2 despite monovalent OPV2 recipients having higher baseline immunity. INTERPRETATION: Both novel OPV2 candidates were safe, well tolerated, and immunogenic in children and infants. Novel OPV2 could be an important addition to our resources against poliovirus given the current epidemiological situation. FUNDING: Fighting Infectious Diseases in Emerging Countries and Bill & Melinda Gates Foundation.
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Seguridad del Paciente , Poliomielitis/prevención & control , Vacuna Antipolio de Virus Inactivados/administración & dosificación , Vacuna Antipolio Oral/administración & dosificación , Poliovirus/inmunología , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Preescolar , Femenino , Humanos , Esquemas de Inmunización , Lactante , Masculino , Panamá , Vacuna Antipolio de Virus Inactivados/inmunología , Vacuna Antipolio Oral/inmunología , Vacunación , Esparcimiento de Virus/inmunologíaRESUMEN
BACKGROUND: Dengue, a mosquito-borne viral disease, was designated a World Health Organization top 10 threat to global health in 2019. METHODS: We present primary efficacy data from part 1 of an ongoing phase 3 randomized trial of a tetravalent dengue vaccine candidate (TAK-003) in regions of Asia and Latin America in which the disease is endemic. Healthy children and adolescents 4 to 16 years of age were randomly assigned in a 2:1 ratio (stratified according to age category and region) to receive two doses of vaccine or placebo 3 months apart. Participants presenting with febrile illness were tested for virologically confirmed dengue by serotype-specific reverse-transcriptase polymerase chain reaction. The primary end point was overall vaccine efficacy in preventing virologically confirmed dengue caused by any dengue virus serotype. RESULTS: Of the 20,071 participants who were given at least one dose of vaccine or placebo (safety population), 19,021 (94.8%) received both injections and were included in the per-protocol analysis. The overall vaccine efficacy in the safety population was 80.9% (95% confidence interval [CI], 75.2 to 85.3; 78 cases per 13,380 [0.5 per 100 person-years] in the vaccine group vs. 199 cases per 6687 [2.5 per 100 person-years] in the placebo group). In the per-protocol analyses, vaccine efficacy was 80.2% (95% CI, 73.3 to 85.3; 61 cases of virologically confirmed dengue in the vaccine group vs. 149 cases in the placebo group), with 95.4% efficacy against dengue leading to hospitalization (95% CI, 88.4 to 98.2; 5 hospitalizations in the vaccine group vs. 53 hospitalizations in the placebo group). Planned exploratory analyses involving the 27.7% of the per-protocol population that was seronegative at baseline showed vaccine efficacy of 74.9% (95% CI, 57.0 to 85.4; 20 cases of virologically confirmed dengue in the vaccine group vs. 39 cases in the placebo group). Efficacy trends varied according to serotype. The incidence of serious adverse events was similar in the vaccine group and placebo group (3.1% and 3.8%, respectively). CONCLUSIONS: TAK-003 was efficacious against symptomatic dengue in countries in which the disease is endemic. (Funded by Takeda Vaccines; TIDES ClinicalTrials.gov number, NCT02747927.).
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Vacunas contra el Dengue/inmunología , Virus del Dengue/inmunología , Dengue/prevención & control , Enfermedades Endémicas/prevención & control , Adolescente , Américas/epidemiología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Asia/epidemiología , Niño , Preescolar , Dengue/epidemiología , Dengue/inmunología , Vacunas contra el Dengue/efectos adversos , Virus del Dengue/aislamiento & purificación , Método Doble Ciego , Femenino , Humanos , Incidencia , Masculino , Serogrupo , Resultado del TratamientoRESUMEN
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.
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Vacunas contra el Dengue/efectos adversos , Virus del Dengue/inmunología , Dengue/prevención & control , Inmunogenicidad Vacunal/inmunología , Adolescente , Niño , Preescolar , Dengue/inmunología , Dengue/virología , Vacunas contra el Dengue/administración & dosificación , Virus del Dengue/genética , República Dominicana/epidemiología , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Inmunización Secundaria/métodos , Masculino , Panamá/epidemiología , Filipinas/epidemiología , Placebos/administración & dosificación , Seguridad , Serogrupo , Vacunación/métodosRESUMEN
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.
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Vacunas contra el Dengue/efectos adversos , Virus del Dengue/inmunología , Dengue/prevención & control , Vacunación/efectos adversos , Adolescente , Brasil/epidemiología , Niño , Preescolar , Colombia/epidemiología , Vacunas contra el Dengue/uso terapéutico , Virus del Dengue/genética , República Dominicana/epidemiología , Método Doble Ciego , Hospitalización/estadística & datos numéricos , Humanos , Nicaragua/epidemiología , Panamá/epidemiología , Filipinas/epidemiología , Placebos/administración & dosificación , Serogrupo , Índice de Severidad de la Enfermedad , Sri Lanka/epidemiología , Tailandia/epidemiología , Resultado del Tratamiento , Vacunación/métodosAsunto(s)
Anticuerpos Monoclonales Humanizados , Antivirales , Enfermedades del Recién Nacido , Recien Nacido Prematuro , Infecciones por Virus Sincitial Respiratorio , Humanos , Lactante , Recién Nacido , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antivirales/uso terapéutico , Hospitalización , Palivizumab , Infecciones por Virus Sincitial Respiratorio/prevención & control , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Nacimiento a Término , Enfermedades del Recién Nacido/tratamiento farmacológico , Enfermedades del Recién Nacido/prevención & controlRESUMEN
Background: The impact of inactivated polio vaccines (IPVs) on intestinal mucosal immune responses to live poliovirus is poorly understood. Methods: In a 2014 phase 2 clinical trial, Panamanian infants were immunized at 6, 10, and 14 weeks of age with bivalent oral polio vaccine (bOPV) and randomized to receive either a novel monovalent high-dose type 2-specific IPV (mIPV2HD) or a standard trivalent IPV at 14 weeks. Infants were challenged at 18 weeks with a monovalent type 2 oral polio vaccine (mOPV2). Infants' intestinal immune responses during the 3 weeks following challenge were investigated by measuring poliovirus type-specific neutralization and immunoglobulin (Ig) A, IgA1, IgA2, IgD, IgG, and IgM antibodies in stool samples. Results: Despite mIPV2HD's 4-fold higher type 2 polio D-antigen content and heightened serum neutralization profile, mIPV2HD-immunized infants' intestinal immune responses to mOPV2 challenge were largely indistinguishable from those receiving standard IPV. Mucosal responses were tightly linked to evidence of active infection and, in the 79% of participants who shed virus, robust type 2-specific IgA responses and stool neutralization were observed by 2 weeks after challenge. Conclusions: Enhancing IPV-induced serum neutralization does not substantively improve intestinal mucosal immune responses or limit viral shedding on mOPV2 challenge. Clinical Trials Registration: NCT02111135.
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Anticuerpos Neutralizantes/análisis , Anticuerpos Antivirales/análisis , Heces/química , Mucosa Intestinal/inmunología , Poliomielitis/prevención & control , Vacuna Antipolio de Virus Inactivados/inmunología , Vacuna Antipolio Oral/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Femenino , Humanos , Inmunidad Mucosa , Inmunoglobulina A/análisis , Inmunoglobulina D/análisis , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Lactante , Masculino , Poliomielitis/inmunología , Vacuna Antipolio de Virus Inactivados/administración & dosificación , Vacuna Antipolio Oral/administración & dosificaciónRESUMEN
OBJECTIVE: To identify the main risk factors associated with neonatal candidemia. PATIENTS AND METHOD: A retrospective paired case-control study was conducted from January 2014 to December 2016. The cases were patients with isolation in blood culture and/or cerebrospinal fluid of Candi da spp. after their first 48 hours in the hospital and the controls cases were neonates chosen from the statistical census of neonatology paired according to their admission date (30-day range), birth weight, gestational age, and discharge condition (alive or deceased). For each case, we select two controls. The risk factors evaluated were intrahospital stay over seven days, use of broad-spectrum antibiotics, mechanical ventilation, parenteral nutrition longer than five days, invasive procedures such as central venous access and abdominal and thoracic surgeries, necrotizing enterocolitis and growth of bacterial microorganisms in blood culture before candidemia. RESULTS: During the study period, 141 patients developed candidemia. 49% of the cases corresponded to Candida parapsilosis with the highest associated lethality rate. The multivariate analysis identified as risk factors hospital stay longer than seven days (OR = 17.0, 95% CI = 2.36-122.4), use of umbilical lines (OR = 9.04, 95% CI = 1.55-52.5), abdominal and/or thoracic surgery (OR = 12.4, 95% CI = 1.76-87.3), and treatment with Meropenem (OR = 4.62, 95% CI = 1.34-15.9). CONCLUSION: Prolonged intrahospital stay longer than seven days and thoracic and/or abdominal surgery were the most significant risk factors in this study for the development of neonatal candidemia.
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Candidemia/etiología , Candidemia/diagnóstico , Candidemia/mortalidad , Estudios de Casos y Controles , Femenino , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Modelos Logísticos , Masculino , Oportunidad Relativa , Panamá/epidemiología , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Background: Quantifying interference of maternal antibodies with immune responses to varying dose schedules of inactivated polio vaccine (IPV) is important for the polio endgame as IPV replaces oral polio vaccine (OPV). Methods: Type 2 poliovirus humoral and intestinal responses were analyzed using pre-IPV type 2 seropositivity as proxy for maternal antibodies from 2 trials in Latin America. Infants received 1 or 2 doses of IPV in sequential IPV-bivalent oral polio vaccine (bOPV) or mixed bOPV-IPV schedules. Results: Among infants vaccinated with bOPV at age 6, 10, and 14 weeks of age and IPV at 14 weeks, those with type 2 pre-IPV seropositivity had lower seroprotection rates than seronegative infants at 4 weeks (92.7% vs 83.8%; difference, 8.9% [95% confidence interval, 0.6%-19.9%]; n = 260) and 22 weeks (82.7% vs 60.4%; difference, 22.3 [12.8%-32.4%]; n = 481) post-IPV. A second IPV at age 36 weeks resulted in 100% seroprotection in both groups. Among infants vaccinated with 1 IPV at age 8 weeks followed by 2 doses of bOPV, pre-IPV type 2-seropositive infants had lower seroprotection at age 28 weeks than those who were seronegative (93.0% vs 73.9%; difference, 19.6% [95% confidence interval, 7.3%-29.4%]; n = 168). A second dose of IPV at 16 weeks achieved >97% seroprotection at age 24 or 28 weeks, regardless of pre-IPV status. Poliovirus shedding after challenge with monovalent OPV, serotype 2, was higher in pre-IPV seropositive infants given sequential IPV-bOPV. No differences were observed in the mixed bOPV-IPV schedule. Conclusions: The presence of maternal antibody is associated with lower type 2 post-IPV seroprotection rates among infants who receive a single dose of IPV. This impact persists until late in infancy and is overcome by a second IPV dose.
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Poliomielitis/prevención & control , Vacuna Antipolio de Virus Inactivados/administración & dosificación , Vacuna Antipolio Oral/administración & dosificación , Poliovirus/inmunología , Vacunación , Femenino , Humanos , Lactante , Intestinos/inmunología , América Latina , Poliomielitis/inmunología , Poliomielitis/virología , Estudios Seroepidemiológicos , SerogrupoRESUMEN
BACKGROUND: The successful implementation of maternal vaccination relies on results of clinical trials, considering the prenatal and postnatal attendance at selected healthcare institutions. This study evaluated factors influencing maternal/infant access to healthcare facilities to identify potential barriers to participation in future clinical trials on maternal vaccination. METHODS: In this prospective, multi-centre, observational study, pregnant women (N = 3243) were enrolled at ten sites across Panama, the Dominican Republic, South Africa, and Mozambique between 2012 and 2014. They completed questionnaires at enrolment, delivery, and infant follow-up (90 days post-partum) visits, including questions on transportation, phone accessibility, alternative childcare, gestational age at enrolment, delivery location, and health status of their infant. Logistic regression was used to identify factors significantly associated with return to study site for delivery or infant follow-up visits. RESULTS: Among 3229 enrolled women with delivery information, 63.6% (range across sites: 25.3-91.5%) returned to study site for delivery. Older women and those at later gestational age at enrolment were more likely to deliver at the study site. While heterogeneities were observed at site level, shorter travel time at delivery and increased transportation costs at enrolment were associated with increased likelihood of women returning to study site for delivery. Among 3145 women with live-born infants, 3077 (95.3%) provided 90-day follow-up information; of these, 68.9% (range across sites: 25.6-98.9%) returned to study site for follow-up visits. Women with other children and with lower transportation costs at delivery were more likely to return to study site for follow-up visits. Among 666 infants reported sick, 94.3% were taken to a healthcare facility, with only 41.9% (range across sites: 4.9-77.3%) to the study site. CONCLUSION: Although high retention was observed from enrolment through 90 days after delivery, post-partum surveillance should be broadened beyond the study sites and additional follow-up visits should be planned within the neonatal period. The factors influencing maternal/infant access to healthcare facilities and the issues identified in this study should be taken into consideration in planning future clinical studies on maternal immunisation in low- and middle-income countries. TRIAL REGISTRATION: The study was registered at ClinicalTrial.gov ( NCT01734434 ) on November 22, 2012.
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Parto Obstétrico/estadística & datos numéricos , Instituciones de Salud/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Programas de Inmunización/estadística & datos numéricos , Servicios de Salud Materno-Infantil/estadística & datos numéricos , Adulto , República Dominicana , Femenino , Edad Gestacional , Estado de Salud , Humanos , Lactante , Recién Nacido , Edad Materna , Mozambique , Panamá , Embarazo , Estudios Prospectivos , Sudáfrica , Transportes/estadística & datos numéricosRESUMEN
BACKGROUND: Replacement of the trivalent oral poliovirus vaccine (tOPV) with bivalent types 1 and 3 oral poliovirus vaccine (bOPV) and global introduction of inactivated poliovirus vaccine (IPV) are major steps in the polio endgame strategy. In this study, we assessed humoral and intestinal immunity in Latin American infants after three doses of bOPV combined with zero, one, or two doses of IPV. METHODS: This open-label randomised controlled multicentre trial was part of a larger study. 6-week-old full-term infants due for their first polio vaccinations, who were healthy on physical examination, with no obvious medical conditions and no known chronic medical disorders, were enrolled from four investigational sites in Colombia, Dominican Republic, Guatemala, and Panama. The infants were randomly assigned by permuted block randomisation (through the use of a computer-generated list, block size 36) to nine groups, of which five will be discussed in this report. These five groups were randomly assigned 1:1:1:1 to four permutations of schedule: groups 1 and 2 (control groups) received bOPV at 6, 10, and 14 weeks; group 3 (also a control group, which did not count as a permutation) received tOPV at 6, 10, and 14 weeks; group 4 received bOPV plus one dose of IPV at 14 weeks; and group 5 received bOPV plus two doses of IPV at 14 and 36 weeks. Infants in all groups were challenged with monovalent type 2 vaccine (mOPV2) at 18 weeks (groups 1, 3, and 4) or 40 weeks (groups 2 and 5). The primary objective was to assess the superiority of bOPV-IPV schedules over bOPV alone, as assessed by the primary endpoints of humoral immunity (neutralising antibodies-ie, seroconversion) to all three serotypes and intestinal immunity (faecal viral shedding post-challenge) to serotype 2, analysed in the per-protocol population. Serious and medically important adverse events were monitored for up to 6 months after the study vaccination. This study is registered with ClinicalTrials.gov, number NCT01831050, and has been completed. FINDINGS: Between May 20, 2013, and Aug 15, 2013, 940 eligible infants were enrolled and randomly assigned to the five treatment groups (210 to group 1, 210 to group 2, 100 to group 3, 210 to group 4, and 210 to group 5). One infant in group 1 was not vaccinated because their parents withdrew consent after enrolment and randomisation, so 939 infants actually received the vaccinations. Three doses of bOPV or tOPV elicited type 1 and 3 seroconversion rates of at least 97·7%. Type 2 seroconversion occurred in 19 of 198 infants (9·6%, 95% CI 6·2-14·5) in the bOPV-only groups, 86 of 88 (97·7%, 92·1-99·4) in the tOPV-only group (p<0·0001 vs bOPV-only), and 156 of 194 (80·4%, 74·3-85·4) infants in the bOPV-one dose of IPV group (p<0·0001 vs bOPV-only). A further 20 of 193 (10%) infants in the latter group seroconverted 1 week after mOPV2 challenge, resulting in around 98% of infants being seropositive against type 2. After a bOPV-two IPV schedule, all 193 infants (100%, 98·0-100; p<0·0001 vs bOPV-only) seroconverted to type 2. IPV induced small but significant decreases in a composite serotype 2 viral shedding index after mOPV2 challenge. 21 serious adverse events were reported in 20 patients during the study, including two that were judged to be possibly related to the vaccines. Most of the serious adverse events (18 [86%] of 21) and 24 (80%) of the 30 important medical events reported were infections and infestations. No deaths occurred during the study. INTERPRETATION: bOPV provided humoral protection similar to tOPV against polio serotypes 1 and 3. After one or two IPV doses in addition to bOPV, 80% and 100% of infants seroconverted, respectively, and the vaccination induced a degree of intestinal immunity against type 2 poliovirus. FUNDING: Bill & Melinda Gates Foundation.
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Anticuerpos Neutralizantes/inmunología , Inmunidad Humoral/inmunología , Inmunidad Mucosa/inmunología , Mucosa Intestinal/inmunología , Poliomielitis/prevención & control , Vacuna Antipolio de Virus Inactivados/uso terapéutico , Vacuna Antipolio Oral/uso terapéutico , Esparcimiento de Virus/inmunología , Colombia , República Dominicana , Quimioterapia Combinada , Heces/virología , Femenino , Guatemala , Humanos , Esquemas de Inmunización , Lactante , América Latina , Masculino , Panamá , Poliomielitis/inmunología , Seroconversión , Método Simple CiegoRESUMEN
BACKGROUND: Group B Streptococcus (GBS) is a leading cause of serious infection in very young infants. Robust incidence data from many geographic regions, including Latin America and Asia, are however lacking. METHODS: A multicenter, hospital-based observational study was performed in Panama, Dominican Republic, Hong Kong and Bangladesh. All represented urban, tertiary referral hospitals, except Bangladesh. GBS cases (microbiological isolation from normally sterile sites in infants aged 0-89 days) were collected over 12 months. RESULTS: At 2.35 (95% CI: 1.74-3.18) cases per 1000 live births, the incidence of early onset GBS disease (EOD) was highest in the Dominican Republic, compared with 0.76 (95% CI: 0.41-1.39) in Hong Kong and 0.77 (95% CI: 0.44-1.35) in Panama, while no cases were identified in Bangladesh. Over 90% of EOD cases occurred on the first day of life, with case fatality ratios ranging from 6.7% to 40%, varying by center, age of onset and clinical presentation. Overall, 90% of GBS (EOD and late onset disease) was due to serotypes Ia, Ib and III. CONCLUSIONS: The incidence rate of early onset GBS infection reported in Dominican Republic was not dissimilar from that described in the United States prior to screening and intrapartum antibiotic prophylaxis, while the incidence in Hong Kong was higher than previously reported in the Asian region. The failure to identify GBS cases in Bangladesh highlights a need to better understand the contribution of population, healthcare and surveillance practice to variation in reported incidence. Overall, the identified disease burden and serotype distribution support the need for effective prevention methods in these populations, and the need for community based surveillance studies in rural areas where access to healthcare may be challenging.
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Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae , Profilaxis Antibiótica , Bangladesh/epidemiología , República Dominicana/epidemiología , Femenino , Hong Kong/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Masculino , Panamá/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/prevención & control , Factores de Riesgo , Serogrupo , Infecciones Estreptocócicas/prevención & control , Infecciones Estreptocócicas/transmisión , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/genéticaRESUMEN
BACKGROUND: The relationship between pneumococcal conjugate vaccine-induced antibody responses and protection against community-acquired pneumonia (CAP) and acute otitis media (AOM) is unclear. This study assessed the impact of the ten-valent pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) on these end points. The primary objective was to demonstrate vaccine efficacy (VE) in a per-protocol analysis against likely bacterial CAP (B-CAP: radiologically confirmed CAP with alveolar consolidation/pleural effusion on chest X-ray, or non-alveolar infiltrates and C-reactive protein ≥ 40 µg/ml); other protocol-specified outcomes were also assessed. METHODS AND FINDINGS: This phase III double-blind randomized controlled study was conducted between 28 June 2007 and 28 July 2011 in Argentine, Panamanian, and Colombian populations with good access to health care. Approximately 24,000 infants received PHiD-CV or hepatitis control vaccine (hepatitis B for primary vaccination, hepatitis A at booster) at 2, 4, 6, and 15-18 mo of age. Interim analysis of the primary end point was planned when 535 first B-CAP episodes, occurring ≥2 wk after dose 3, were identified in the per-protocol cohort. After a mean follow-up of 23 mo (PHiD-CV, n = 10,295; control, n = 10,201), per-protocol VE was 22.0% (95% CI: 7.7, 34.2; one-sided p = 0.002) against B-CAP (conclusive for primary objective) and 25.7% (95% CI: 8.4%, 39.6%) against World Health Organization-defined consolidated CAP. Intent-to-treat VE was 18.2% (95% CI: 5.5%, 29.1%) against B-CAP and 23.4% (95% CI: 8.8%, 35.7%) against consolidated CAP. End-of-study per-protocol analyses were performed after a mean follow-up of 28-30 mo for CAP and invasive pneumococcal disease (IPD) (PHiD-CV, n = 10,211; control, n = 10,140) and AOM (n = 3,010 and 2,979, respectively). Per-protocol VE was 16.1% (95% CI: -1.1%, 30.4%; one-sided p = 0.032) against clinically confirmed AOM, 67.1% (95% CI: 17.0%, 86.9%) against vaccine serotype clinically confirmed AOM, 100% (95% CI: 74.3%, 100%) against vaccine serotype IPD, and 65.0% (95% CI: 11.1%, 86.2%) against any IPD. Results were consistent between intent-to-treat and per-protocol analyses. Serious adverse events were reported for 21.5% (95% CI: 20.7%, 22.2%) and 22.6% (95% CI: 21.9%, 23.4%) of PHiD-CV and control recipients, respectively. There were 19 deaths (n = 11,798; 0.16%) in the PHiD-CV group and 26 deaths (n = 11,799; 0.22%) in the control group. A significant study limitation was the lower than expected number of captured AOM cases. CONCLUSIONS: Efficacy was demonstrated against a broad range of pneumococcal diseases commonly encountered in young children in clinical practice. TRIAL REGISTRATION: www.ClinicalTrials.gov NCT00466947.
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Proteínas Bacterianas/inmunología , Proteínas Portadoras/inmunología , Haemophilus influenzae/inmunología , Inmunoglobulina D/inmunología , Lipoproteínas/inmunología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/inmunología , Streptococcus pneumoniae/inmunología , Vacunación , Vacunas Conjugadas/inmunología , Anticuerpos Antibacterianos/sangre , Preescolar , Método Doble Ciego , Infecciones por Haemophilus/microbiología , Humanos , Inmunización Secundaria , Lactante , Análisis de Intención de Tratar , América Latina , Otitis Media/inmunología , Otitis Media/microbiología , Otitis Media/prevención & control , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/microbiología , Resultado del TratamientoRESUMEN
INTRODUCTION: Dengue disease represents a large and growing global threat to public health, accounting for a significant burden to health systems of endemic countries. The World Health Organization's (WHO) Strategic Advisory Group of Experts (SAGE) and the European Medicines Agency (EMA) currently recommend the use of TAK-003 dengue vaccine in high dengue burden and transmission settings for countries considering vaccination as part of their integrated management strategy for prevention and control of Dengue. AREAS COVERED: This paper describes the main conclusions of a workshop held by the Arbovirus Committee of the Latin American Society of Pediatric Infectious Diseases (SLIPE) in November 2024, to generate consensus recommendations on the introduction of this new vaccine in the region. Considerations were made regarding the molecular epidemiology of dengue infection in the Americas and the need for more precise phylogenetic classification and correlation with clinical outcome and disease severity. EXPERT OPINION: Introduction of dengue vaccine should be considered as an strategy for health entities in the region, with participation of social sectors, scientific societies, and ministries of health that could be able to create a successful vaccination program.