Global Dengue & Aedes-Transmitted Diseases Consortium (GDAC) statement on publication of Part 1 results from Takeda’s dengue vaccine Phase 3 efficacy trial
November 19, 2019 - Singapore
The results from Part 1 of Takeda’s Phase 3 clinical trial of TAK-003, a live-attenuated tetravalent dengue vaccine candidate, were recently published in the New England Journal of Medicine. The vaccine was found to be efficacious up to 15 months after administration of the first vaccine dose in trial participants regardless of pre-vaccination dengue infection status (i.e., serostatus) for dengue virus serotypes 1 and 2, and only in dengue seropositive participants for serotype 3. Too few DENV-4 infections were seen to draw any conclusion. TAK-003 performed especially well against serotype 2.
Takeda’s pivotal Phase 3 trial, known as the Tetravalent Immunization against Dengue Efficacy Study (TIDES) conducted in Latin America (Brazil, Colombia, Dominican Republic, Nicaragua and Panama) and Asia (The Philippines, Sri Lanka and Thailand), evaluated the efficacy and safety of two doses of TAK-003 given subcutaneously three months apart to over 20,000 children and adolescents aged 4 to 16 years. The trial is being undertaken in three stages: Part 1 evaluates vaccine efficacy up to 15 months after the first dose; Part 2 will obtain an additional 6 months of data to assess efficacy by dengue virus serotype, pre-vaccination dengue serostatus, and disease severity; Part 3 will evaluate long-term safety for an additional 3 years. The results published on November 6, 2019 are from Part 1 of the trial, with results from Part 2 to be presented later this month at the annual meeting of the American Society of Tropical Medicine and Hygiene. Takeda has stated that data from Part 1 and Part 2 will form the basis for filing for licensure.
The Global Dengue & Aedes-Transmitted Diseases Consortium (GDAC) considers the published results of Part 1 to be an important and incremental development after the results of Sanofi Pasteur’s Dengvaxia®, which was found to have an increased risk of hospitalized and severe dengue in vaccine recipients who were dengue seronegative prior to vaccination. The performance of Takeda’s TAK-003 among dengue seronegative vaccine recipients against serotypes 1 and 2 is encouraging. Although limited to a 15-month follow up of per-protocol results, the preliminary data show an overall efficacy against virologically confirmed dengue of 80.2% and a 95.4% decrease in hospitalization. The data further suggest that a single dose of TAK003 provides protection, indicating that the vaccine may be useful as an emergency response tool to control epidemics. The numbers of recipients who developed severe disease were too small to draw any conclusions about preventing severe disease. GDAC looks forward to the release of Part 2 data in the near future, especially TAK-003’s further evaluation of performance in seronegative vaccine recipients and against serotypes 3 and 4. Additional data from Parts 2 and 3 will help clarify the potential utility of TAK-003 as a public health tool.
Dengue is the most common vector-borne viral disease of humans. Dengue causes an estimated 390 million infections per year in over 120 countries, threatening the health of over 50% of the global population. Comprehensive prevention and control measures are urgently needed, including safe and effective vaccines and vector control methods.
GDAC is an international consortium that seeks to promote the development and implementation of innovative and synergistic approaches for prevention and control of dengue and other diseases transmitted by Aedes mosquitoes. GDAC is supported in part by the Bill & Melinda Gates Foundation and unrestricted grants from industry sponsors including Takeda and Sanofi Pasteur.