GDAC statement on Takeda’s announcement about their Dengue vaccine phase 3 efficacy trial
January 30, 2019 - Seoul (South Korea)
Yesterday, Takeda Pharmaceutical Company Limited announced their live-attenuated tetravalent dengue vaccine candidate, designated as TAK-003, had met the primary endpoint in a pivotal Phase 3 clinical trial being conducted in Latin America (Brazil, Colombia, Dominican Republic, Nicaragua and Panama) and Asia (The Philippines, Sri Lanka and Thailand). TAK-003 was found to be efficacious among trial participants in preventing symptomatic dengue of any severity caused by any of the four dengue virus serotypes up to 15 months after administration of the first vaccine dose.
Takeda’s pivotal Phase 3 trial, known as the Tetravalent Immunization against Dengue Efficacy Study (TIDES), evaluated the efficacy and safety of two doses of TAK-003 given subcutaneously three months apart in 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 infection status (i.e., dengue serostatus), and disease severity; Part 3 will evaluate long-term safety for an additional 3 years. The results announced yesterday are from Part 1 of the trial, with results from Part 2 expected later this year. Takeda 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 today’s announcement by Takeda to be an exciting advance in efforts to develop dengue vaccines. Takeda’s Phase 3 trial announcement comes after the only currently licensed dengue vaccine, Sanofi Pasteur’s Dengvaxia®, was found to have an increased risk of hospitalized and severe dengue in vaccine recipients who did not have evidence of dengue infection prior to vaccine administration (i.e., were dengue seronegative), leading to the World Health Organization (WHO) position in September 2018 recommending only those individuals having evidence of previous dengue infection to receive Dengvaxia®. Given the issues highlighted by the experience with Dengvaxia®, the performance of Takeda’s TAK-003 among dengue seronegative vaccine recipients will be critical. With this understanding, Takeda collected baseline blood samples from all TIDES participants to allow for evaluation of safety and efficacy based on serostatus before vaccination. GDAC looks forward to the release of more detailed analysis of Part 1 data in the near future, especially TAK-003’s performance in seronegative vaccine recipients and against different dengue virus serotypes, along with results from Part 2 of TIDES later this year. This more comprehensive analysis of TAK-003’s performance 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.