New Phase 3 Data Show Takeda’s Dengue Vaccine Delivers 7 Years of Sustained Protection Against Infection and Hospitalization

Takeda (TSE:4502/NYSE:TAK) announced the completion of the 7-year pivotal Phase 3 Tetravalent Immunization against Dengue Efficacy Study (TIDES) trial evaluating its dengue vaccine, QDENGA^®▼(Dengue Tetravalent Vaccine [Live, Attenuated]) (TAK-003). These data, including an exploratory analysis of a booster dose, confirm the favorable benefit and risk profile of QDENGA and that the two-dose regimen provides sustained protection against dengue. This is consistent with its approved indications in multiple countries worldwide, which could simplify vaccination schedules and increase adherence.

“We are seeing an unprecedented surge in dengue, with over 14 million cases reported across more than 100 countries in 2024 alone, largely driven by the impacts of climate change and inadequate urbanization. Brazil, consistently among the countries most impacted by dengue, has contributed to the record-breaking number of dengue cases and rise in severity and deaths. This surge highlights the urgent need for prevention methods like QDENGA,” said Edson Moreira, M.D., Senior Researcher at Oswaldo Cruz Foundation, Brazilian Ministry of Health. “The inclusion of QDENGA in Brazil's public vaccination program has reduced symptomatic dengue cases and dengue-related hospitalizations.”

After 4.5 years, two doses of QDENGA provided 61.2% [95% CI: 56.0, 65.8] vaccine efficacy (VE) in preventing virologically confirmed dengue (VCD).¹ A booster dose administered at 4.5 years only marginally increased efficacy to 74.3% [95% CI: 66.7, 80.1] after 2 years.² QDENGA showed 84.1% [95% CI: 77.8, 88.6] VE in preventing dengue-related hospitalizations at 4.5 years, and VE remained consistently high at 90.6% [95% CI: 78.9, 95.8] after the booster dose.^1,2 Overall efficacy was seen across all four dengue virus serotypes through seven years. No new safety signals were observed following the administration of a booster dose.

“QDENGA is the most comprehensively studied dengue vaccine, with more than 60,000 participants globally in the clinical program, and these long-term data highlight the durability of its safety and efficacy profile, across diverse populations worldwide," said Derek Wallace, M.D., president of the Global Vaccine Business Unit at Takeda. “We are proud to have worked hand-in-hand with the clinical trial participants, collaborators and investigators whose contributions have been integral to the success of the TIDES trial and played a role in helping us move closer to a dengue-free world.”

Takeda continues to invest in post-marketing research through real-world evidence generation and ongoing pharmacovigilance to deepen understanding of the vaccine’s safety and impact. This includes an Impact Study in the municipality of Dourados, Brazil in partnership with the Dourados Health Department and a Brazilian researcher, as well as the DEN-401 study, an observational, post-authorization effectiveness study of QDENGA in children and adolescents in Southeast Asia.

Since its first approval in Indonesia in 2022, QDENGA has been authorized in 41 countries and 18.6 million doses have been distributed in 11 endemic countries as of September 2025. The World Health Organization added QDENGA to its List of Prequalified Vaccines underscoring its quality and suitability for public vaccination programs to help address the global dengue threat.

These data were presented at the World Society for Pediatric Infectious Diseases (WSPID) 14th Annual Congress on October 29, 2025.² Takeda plans to share results from additional non-endemic booster studies at the American Society of Tropical Medicine and Hygiene (ASTMH) Annual Congress on November 11, 2025.

About the Phase 3 TIDES (DEN-301) Trial

The double-blind, randomized, placebo-controlled Phase 3 TIDES trial evaluated the safety and efficacy of two doses of TAK-003 in the prevention of laboratory-confirmed symptomatic dengue fever of any severity and due to any of the four dengue virus serotypes in more than 20,000 healthy children and adolescents 4-16 years of age.³ Study participants were randomized 2:1 to receive two doses of TAK-003 0.5 mL or placebo on months 0 and 3, administered subcutaneously.³ The study is comprised of five parts. Part 1 and the primary endpoint analysis evaluated VE and safety through 12 months after the second dose.³ Part 2 continued for an additional six months to complete the assessment of the secondary endpoints of VE by serotype, baseline serostatus and disease severity, including VE against hospitalized dengue.³ Part 3 evaluated VE and long-term safety by following participants for an additional two and a half to three years, as per World Health Organization recommendations.⁴ Part 4 evaluated efficacy and safety for 13 months following booster vaccination, and Part 5 evaluated long-term efficacy and safety for one year following the completion of Part 4.³

The trial took place at sites across 8 dengue-endemic countries in Latin America (Brazil, Colombia, Panama, the Dominican Republic and Nicaragua) and Asia (Philippines, Thailand and Sri Lanka) where there are unmet needs in dengue prevention and where severe dengue is a leading cause of serious illness and death among children.⁵ Baseline blood samples were collected from all individuals participating in the trial to allow for evaluation of safety and efficacy based on serostatus.³ The Phase 3 TIDES trial is Takeda’s largest interventional clinical trial to date. Takeda and an independent Data Monitoring Committee of experts are actively monitoring safety on an ongoing basis.

About QDENGA^®▼ (Dengue Tetravalent Vaccine [Live, Attenuated])

QDENGA^® (TAK-003) is a dengue vaccine that is based on a live-attenuated dengue serotype 2 virus, which provides the genetic “backbone” for all four dengue virus serotypes and is designed to help protect against any of these serotypes.⁶

In the European Union (EU) Member States, QDENGA is indicated for the prevention of dengue disease in individuals from four years of age and should be administered subcutaneously as a 0.5 mL dose at a two-dose (0 and 3 months) schedule pursuant to approved dosing regimen.⁷

Always consult your local prescribing information before prescribing. The local label may vary.

Important Safety Information

Please consult the Summary of Product Characteristics (SmPC) before prescribing.

Guidance for use: QDENGA should be administered by subcutaneous injection preferably in the upper arm in the region of deltoid. QDENGA must not be injected intravascularly, intradermally or intramuscularly. Vaccination should be postponed in subjects suffering from an acute severe febrile illness. The presence of a minor infection, such as a cold, should not result in a deferral of vaccination. Vaccination should be preceded by a review of the individual’s medical history (especially with regards to previous vaccination and possible hypersensitivity reactions which occurred after vaccination). Appropriate medical treatment and supervision must always be readily available in the event of a rare anaphylactic reaction following administration of the vaccine. Anxiety-related reactions, including vasovagal reactions (syncope), hyperventilation or stress-related reactions may occur in association with vaccination as a psychogenic response to the needle injection. It is important that precautions are in place to avoid injury from fainting. A protective immune response with QDENGA may not be elicited in all vaccinees against all serotypes of dengue virus and may decline over time. It is currently unknown whether a lack of protection could result in an increased severity of dengue. It is recommended to continue personal protection measures against mosquito bites after vaccination. Individuals should seek medical care if they develop dengue symptoms or dengue warning signs.

Contraindications: Hypersensitivity to the active substances or to any of the excipients listed in section 6.1 or hypersensitivity to a previous dose of QDENGA. Individuals with congenital or acquired immune deficiency, including those receiving immunosuppressive therapies such as high doses of systemic corticosteroids (e.g. 20 mg/day or 2 mg/kg body weight/day of prednisone for 2 weeks or more) within 4 weeks prior to vaccination, or any other medicinal product with known immunosuppressive properties including chemotherapy. The time to avoid vaccination after immunosuppressive treatment should be considered on an individual basis. Individuals with symptomatic HIV infection or with asymptomatic HIV infection when accompanied by evidence of impaired immune function. Pregnant women (see section 4.6). Breast-feeding women (see section 4.6).

▼ This medicinal product is subject to additional monitoring. This will allow quick identification of new safety information. Healthcare professionals are asked to report any suspected adverse reactions. See section 4.8 for how to report adverse reactions.

Adverse Reactions: Most frequently reported reactions in subjects 4 to 60 years of age were injection site pain (50%), headache (35%), myalgia (31%), injection site erythema (27%), malaise (24%), asthenia (20%), and fever (11%). Very common: (≥1/10 of subjects): upper respiratory tract infection,^a decreased appetite,^c irritability,^c headache, somnolence^c, myalgia, injection site pain, injection site erythema, malaise, asthenia, fever. Common (≥1/100 to <1/10): nasopharyngitis, pharyngotonsillitis,^b arthralgia, injection site swelling, injection site bruising,^e injection site pruritus,^e influenza like illness.^a Includes upper respiratory tract infection and viral upper respiratory tract infection.^b Includes pharyngotonsillitis and tonsillitis.^c Collected in children below 6 years of age in clinical studies.^d Includes rash, viral rash, rash maculopapular, and rash pruritic.^e Reported in adults in clinical studies. Refer to the SmPC for details on full side effect profile and interactions.

For full prescribing information, please see the Summary of Product Characteristics(SmPC) for QDENGA^®▼.

Please consult with your local regulatory agency for any approved labeling in your country.

The drug information contained herein is intended to disclose corporate information. Nothing contained in this document should be considered a solicitation, promotion, or indication for any prescription drug, including those currently under development.

About Dengue

Dengue is a rapidly spreading mosquito-borne viral disease that is now endemic in more than 100 countries on all continents.⁸ Dengue is mainly spread by Aedes aegypti mosquitoes and, to a lesser extent, Aedes albopictus mosquitoes.⁸ It is caused by any of four dengue virus serotypes, each of which can cause dengue fever or severe dengue.⁸ The prevalence of individual serotypes varies across different geographies, countries, regions, seasons and over time.⁸ Infection by one can provide lifelong protection against that one dengue serotype and temporary immunity against the three other serotypes.⁸ A second infection with a different serotype can be worse in some cases.⁸

Takeda’s Commitment to Vaccines

Vaccines prevent 3.5 to 5 million deaths each year and have transformed global public health.⁹ For more than 70 years, Takeda has supplied vaccines to protect the health of people in Japan. Today, Takeda’s global vaccine business is applying innovation to tackle some of the world’s most challenging infectious diseases, such as dengue, COVID-19 and pandemic flu. Takeda’s team brings an outstanding track record and a wealth of knowledge in vaccine development and manufacturing to advance a pipeline of vaccines to address some of the world’s most pressing public health needs.

About Takeda

Takeda is focused on creating better health for people and a brighter future for the world. We aim to discover and deliver life-transforming treatments in our core therapeutic and business areas, including gastrointestinal and inflammation, rare diseases, plasma-derived therapies, oncology, neuroscience and vaccines. Together with our partners, we aim to improve the patient experience and advance a new frontier of treatment options through our dynamic and diverse pipeline. As a leading values-based, R&D-driven biopharmaceutical company headquartered in Japan, we are guided by our commitment to patients, our people and the planet. Our employees in approximately 80 countries and regions are driven by our purpose and are grounded in the values that have defined us for more than two centuries. For more information, visit www.takeda.com.

Important Notice

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Medical Information

This press release contains information about products that may not be available in all countries, or may be available under different trademarks, for different indications, in different dosages, or in different strengths. Nothing contained herein should be considered a solicitation, promotion or advertisement for any prescription drugs including the ones under development.

References

¹ Tricou, V. Efficacy and Safety of Takeda’s Tetravalent Dengue Vaccine Candidate (TAK-003) After 4.5 Years of Follow-Up. Presented at the 8 Northern European Conference of Travel Medicine; June 2022.
² Escudero, I. Evaluation of a Booster Dose of the Tetravalent Dengue Vaccine, TAK-003, in Healthy Children in Dengue-Endemic Regions (DEN-301). Oral presentation at: World Congress of the World Society for Pediatric Infectious Diseases (WSPID 2025), October 29, 2025. Bangkok, TH. OP010.
³ ClinicalTrials.Gov. Efficacy, Safety and Immunogenicity of Takeda’s Tetravalent Dengue Vaccine (TDV) in Healthy Children (TIDES). Retrieved November 2025.
⁴ World Health Organization (WHO) Technical Report Series No. 979, 2013 Annex 2. Guidelines on the quality, safety and efficacy of dengue tetravalent vaccines (live, attenuated). https://cdn.who.int/media/docs/default-source/biologicals/vaccine-standardization/dengue/trs-979-annex-2-dengue.pdf?sfvrsn=bd659777_2&download=true.
⁵ Murray, et al. Epidemiology of dengue: past, present and future prospects. Clin Epidemiol. 2013 Aug 20;5:299-309. doi: 10.2147/CLEP.S34440.
⁶ Huang CY-H, et al. Genetic and phenotypic characterization of manufacturing seeds for tetravalent dengue vaccine (DENVax). PLoS Negl Trop Dis. 2013;7:e2243
⁷ Takeda. QDENGA Summary of Product Characteristics. Retrieved November 2025.
⁸ World Health Organization. Dengue. Published August 21, 2025.
⁹ World Health Organization. Vaccines and immunization. Retrieved November 2025.

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