CompletedPhase 3

Long-Term Safety and Antibody Persistence of TDV and the Impact of a Booster Dose

United States, Mexico365 participantsStarted 2019-11-12

Plain-language summary

The purpose of this study is to describe antibody persistence for each of the 4 dengue serotypes for up to 63 months after the first vaccination in the primary vaccination series for participants from parent trial DEN-315 (NCT03341637) (Mexico) and for up to 36 months after the first vaccination in the primary vaccination series for participants from parent trial DEN-304 (NCT03423173) (United States \[US\]) and to describe the impact of a tetravalent dengue vaccine (TDV) booster dose vs placebo on antibody response for each of the 4 dengue serotypes at 1 month and 6 months post administration of the TDV booster or placebo.

Who can participate

Age range

13 Years – 63 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Exclusion criteria

. Participants with a prolonged period of habitation (≥1 year) in a dengue endemic area within the 2 years prior to Visit 1 Day 1 (Month 0).
. Previous and planned vaccination (during the trial conduct), against any flavivirus including dengue (other than Takeda's TDV), yellow fever (YF), Japanese encephalitis (JE) viruses or tick-borne encephalitis.
. Participants for whom baseline serostatus is not defined in the parent trials (DEN-304 \[(NCT03423173)\] and DEN-315 \[NCT03341637\]).
. Participants with any history of progressive or severe neurologic disorder, seizure disorder or neuro-inflammatory disease (eg, Guillain-Barré syndrome).
. Known or suspected impairment/alteration of immune function, including:
. Chronic use of oral steroids (equivalent to 20 mg/day prednisone ≥12 weeks/≥2 mg/kg body weight/day prednisone ≥2 weeks) within 60 days prior to Month 42 for participants from parent trial DEN-315 (Mexico)/ Month 15 for participants from parent trial DEN-304 (US); use of inhaled, intranasal, or topical corticosteroids is allowed.

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Geometric Mean Titers (GMTs) of Neutralizing Antibodies for Each of the 4 Dengue Serotypes in the Period Prior to Booster at Visit 1 (Month 0 [Day 1])

Timeframe: Month 0 (Day 1)

Geometric Mean Titers (GMTs) of Neutralizing Antibodies for Each of the 4 Dengue Serotypes in the Period Prior to Booster at Visit 2 (Month 12)

Timeframe: Month 12

Geometric Mean Titers (GMTs) of Neutralizing Antibodies for Each of the 4 Dengue Serotypes in the Period Prior to Booster at Visit 3 (Month 15) (DEN-304)

Timeframe: Month 15 (DEN-304)

Geometric Mean Titers (GMTs) of Neutralizing Antibodies for Each of the 4 Dengue Serotypes in the Period Prior to Booster at Visit 3 (Month 42) (DEN-315)

Timeframe: Month 42 (DEN-315)

Geometric Mean Titers (GMTs) of Neutralizing Antibodies for Each of the 4 Dengue Serotypes in the Period Prior to Booster by Serostatus at Baseline in the Parent Trials at Visit 1 (Month 0 [Day 1])

Timeframe: Month 0 [Day 1)

Geometric Mean Titers (GMTs) of Neutralizing Antibodies for Each of the 4 Dengue Serotypes in the Period Prior to Booster by Serostatus at Baseline in the Parent Trials at Visit 2 (Month 12)

Trial details

NCT IDNCT03999996

SponsorTakeda

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2024-05-25

Results submitted2025-05-23

View on ClinicalTrials.gov More Dengue Fever trials