Browsing by Author "López-Medina, E."

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Efficacy of a dengue vaccine candidate (TAK-003) in healthy children and adolescents two years after vaccination
(University of Chicago Press, 2022) López-Medina, E.; Biswal, S.; Saez-Llorens, X.; Borja-Tabora, C.; Bravo, L.; Sirivichayakul, C.; Vargas, L.M.; Alera, M.T.; Velásquez, H.; Reynales, H.; Rivera, L.; Watanaveeradej, V.; Rodriguez-Arenales, E.J.; Yu, D.; Espinoza, F.; Dietze, R.; Fernando, L.; Wickramasinghe, P.; Moreira Jr, E.D.; Fernando, A.D.; Gunasekera, D.; Luz, K.; da Cunha, R.V.; Tricou, V.; Rauscher, M.; Liu, M.; LeFevre, I.; Wallace, D.; Kosalaraksa, P.; Borkowski, A.; TIDES study group.
BACKGROUND: Takeda's dengue vaccine is under evaluation in an ongoing Phase 3 efficacy study; we present an update after 2 years. METHODS: 20,099 children (4-16 years old) were randomized to receive two doses of TAK-003 or placebo three months apart and are under long-term febrile surveillance to detect dengue by serotype-specific RT-PCR. (NCT02747927). RESULTS: Cumulative efficacy against dengue over ~27 months since first dose was 72.7% (95% CI: 67.1 - 77.3), which included efficacy of 67.0% (95% CI: 53.6 - 76.5) in dengue-naïve and 89.2% (82.4 - 93.3) against hospitalized dengue. In the second year after vaccination, a decline in efficacy was observed [56.2% (42.3 - 66.8)] with the largest decline in 4 - 5 year-old children [24.5% (-34.2 - 57.5)]; efficacy was 60.6% (43.8 - 72.4) in 6 - 11 year and 71.2% (41.0 - 85.9) in 12 - 16 year age groups. As TAK-003 efficacy varies by serotype, changes in serotype dominance partially contributed to the efficacy differences in year by year analysis. No related serious adverse events occurred during the second year. CONCLUSION: 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. KEYWORDS: Dengue; TAK-003; efficacy; immunogenicity; persistence; safety; vaccine.
Efficacy of a tetravalent dengue vaccine in healthy children aged 4-16 years: A Randomised, placebo-controlled, phase 3 trial
(J. Onwhyn, 2020) Biswal, S.; Borja-Tabora, C.; Martinez Vargas, L.; Velásquez, H.; Theresa Alera, M.; Sierra, V.; Johana Rodriguez-Arenales, E.; Yu, D.; Wickramasinghe, V.P.; Duarte Moreira, E. Jr.; Fernando, A. D.; Gunasekera, D.; Kosalaraksa, P.; Espinoza, F.; López-Medina, E.; Bravo, L.; Tuboi, S.; Hutagalung, Y.; Garbes, P.; Escudero, I.; Rauscher, M.; Bizjajeva, S.; LeFevre, I.; Borkowski, A.; Saez-Llorens, X.; Wallace, D.; TIDES study group
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: 20 099 participants were randomly assigned and vaccinated between Sept 7, 2016, and Aug 18, 2017; 19 021 (94·6%) were included in the per protocol analysis, and 20 071 (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. INTERPRITATION: 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.
Three years efficacy and safety of Takeda's dengue vaccine candidate (TAK-003)
(Oxford University Press, 2022) Rivera, L.; Biswal, S.; Sáez-Llorens, X.; Reynales, H.; López-Medina, E.; Borja-Tabora, C.; Bravo, L.; Sirivichayakul, C.; Kosalaraksa, P.; Vargas, L.M.; Yu, D.; Watanaveeradej, V.; Espinoza, F.; Dietze, R.; Fernando, L.; Wickramasinghe, P.; Duarte Moreira, E. J.; Fernando, A. D.; Gunasekera, D.; Luz, K.; Venâncio da Cunha, R.; Rauscher, M.; Zent, O.; Liu, M.; Hoffman, E.; LeFevre, I.; Tricou, V.; Wallace, D.; Alera, M.T.; Borkowski, A.
Background: Takeda's live attenuated tetravalent dengue vaccine candidate (TAK-003) is under evaluation in a long-term clinical trial across eight 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 post-vaccination. This exploratory analysis provides an update with cumulative and third year data. Methods: Healthy 4-16 year-olds (n=20,099) 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 RT-PCR. Results: Cumulative efficacy after three 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 seropositives. Efficacy against VCD during the third year declined to 44.7% (32.5%, 54.7%), while 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 (i.e. second half of the three years following vaccination), but none were related. No important safety risks were identified. Conclusions: TAK-003 was efficacious against symptomatic dengue over three years. Efficacy declined over time but remained robust against hospitalized dengue. A booster dose evaluation is planned.