ClinicalTrials.gg
Not yet recruitingNCT06908018DHIT-ImmuneUpdated Apr 3, 2025

Safety, Virological and Immunological Assessment of the Controlled Dengue Human Infection Model in Dengue-Immune Participants in Thailand (DHIT-Immune)

An Early Phase 1 interventional study of rDEN2Δ30-7169 in Safety Issues, Dengue and Viremia, sponsored by Mahidol University. Not yet recruiting. Open to participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-04-03.

Sponsored by Mahidol University · Early Phase 1, Interventional, and Other

From the registry’s dates

  • Primary completion was expected by Jun 2026, 5 months ago, but the record still lists the study as not yet recruiting.
Phase
Early Phase 1
Study type
Interventional
Enrollment
12
Allocation
Not applicable
Ages
18 Years to 40 Years
Sex
All
01

Study summary

rDEN2Δ30-7169 is a dengue challenge strain that previously reports its viremia induction effect in participants with minimal symptoms in US flavivirus naïve participants. Moreover, preliminary result of five Thai dengue naïve participants from previous project (registered number NCT05476757) demonstrated 100% viremia status without severe adverse event after 60 days post-virus challenge. However, result from previous project may not fully represent the clinical manifestation and immunological responses of major population of endemic areas, where most people in endemic area have dengue immune status. Therefore, this controlled human infection model protocol proposes to challenge the attenuated virus in 12 dengue-immune participants recruited from Bangkok metropolitan area, Thailand. We aim to assess the safety, viremia, NS1 antigenemia profile, and immunogenicity of the challenge virus in the dengue immune participants. After finish safety assessment, all participants will be vaccinated with a full course of dengue vaccines to prevent recurrent dengue infection. Immunological responses after vaccination will be also evaluated the vaccine efficacy.

Our expected outcomes are all participants present viremia profiles after virus challenge without serious adverse events (SAE). The exploratory profiles include assesment of immune profiles and parameters comparison with the other dengue challenge study.

02

Conditions studied

  • Safety Issues
  • Dengue
  • Viremia
  • Immune-related Adverse Event

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03

In context

Dengue

283 studies on the registry are indexed under Dengue; 44 are open to participants now.

This study's planned enrollment of 12 is below the median of 132 across 197 interventional studies indexed under Dengue.

Browse Dengue studies →

Lead sponsor

Mahidol University is the lead sponsor of 747 studies on the registry; 119 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 40 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Thai healthy volunteers, aged between 18 to 40 years old, weight is greater than or equal to 50 kg and have Thai language literacy.
  2. Have not given blood donation in the past 3 months.
  3. Education: high school diploma or above
  4. Positive dengue-immune status against DENV-1 and/or DENV-3 and/or DENV-4 with naive DENV-2 status by the standard FRNT 50% (FRNT50) as follows: FRNT50 titer against

    • DENV1 ≥ 1:5 and/or
    • DENV3 ≥ 1:5 and/or
    • DENV4 ≥ 1:5 with
    • DENV2 ≤ 1:16
  5. Willingness to participate in the study as evidenced by signing the document.
  6. Female participants of should be agreed to either abstinence or use at least one primary form of from the time of screening for rDEN2Δ30-7169 administration until 1 month after complete course of Dengue vaccination (Study Day 298).

Exclusion criteria

Exclusion Criteria:

  1. For female participants: Currently pregnant, as determined by positive urine human choriogonadotropin (HCG) test or breast-feeding, and given birth or abortion within 6 months.
  2. History of previous acute undifferentiated febrile illness leading to hospitalization in the past 3 months.
  3. Behavioral, cognitive, or psychiatric disease that, in the opinion of the investigator, affects the subject's ability to understand and cooperate with the requirements of the study protocol.
  4. Any significant alcohol or drug abuse in the past 12 months that has caused medical, occupational, or family problems, as indicated by subject history.
  5. History of a severe allergic reaction or anaphylaxis.
  6. Severe asthma (emergency room visit or hospitalization within the last 6 months).
  7. Any known immunodeficiency syndrome.
  8. Having any pre-existing medical conditions consist of thrombocytopenia, disease and cancer based on history, physical examination, and/or laboratory studies.
  9. Current use of anticoagulant medications (this includes anti- medication such as aspirin or non-steroidal anti-inflammatory medications).
  10. Use of (excluding topical or nasal) or drugs within 28 days prior to or following vaccination. An immunosuppressive dose of corticosteroids is defined as ≥ 10 mg of a prednisone equivalent per day for ≥ 14 days.
  11. Asplenia
  12. Receipt of any vaccine within 28 days or a killed vaccine within 14 days prior to receiving virus administration, or anticipated receipt of any vaccine during the 28 days following rDEN2Δ30-7169 administration.
  13. Has an obvious history of receiving any type of dengue vaccine or has previously participated in dengue vaccine research.
  14. Receipt of blood products within the past 6 months, including transfusions or immunoglobulin, or anticipated receipt of any blood products or immunoglobulin during the 28 days following rDEN2Δ30-7169 administration.
  15. History of allergy to Qdenga vaccine or any components of the vaccine.
  16. Previous episode of severe dengue infection defined by WHO 2009
  17. Screening laboratory values of Grade 1 or above (as defined in this protocol) for (\<750 /mm3), Platelet (\<100,000 /mm3), PT (> 1.25 x ), (> 1.66 x ULN), (>2.5 x ULN) and plasma creatinine (> 1.3 x ULN OR Increase to >1.3 x participant's baseline).
  18. A participant with level less than 10 g/dL at initial screening.
  19. Body temperature is greater than or equal to 38.0 °C (Oral)
  20. infection, as indicated by anti-HIV screening assays.
  21. virus (HCV) infection, as indicated by anti-HCV screening assays.
  22. virus (HBV) infection, as indicated by hepatitis B surface antigen (HBsAg) and/or anti-HBc screening.
  23. Any other condition that, in the opinion of the investigator, would jeopardize the safety or rights of a subject participating in the trial, or would render the subject unable to comply with the protocol.
Terms in these criteria, in plain language(15)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Autoimmune disease

A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.

Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Absolute neutrophil count (ANC)

The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.

It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

INR, PT and aPTT (clotting tests)

Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.

Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

05

Study design

Phase
Early Phase 1
Primary purpose
Other
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
12 participants (estimated)

Study arms

  • Experimental
    Open label DENV2delta30 virus challenge

    Biological: rDEN2Δ30-7169

Interventions

  • BiologicalrDEN2Δ30-7169

    rDEN2Δ30-7169 is a recombinat virus that could induce viremia and immunological responses with out serious adverse effect. The virus will be challenged after participants screening and consent for hospitalization. After virus challenge, the virological, immunological and clinical manifestation will be recorded and analyzed for the result from day 0-60 post-virus challenge.

06

What researchers measure

Primary outcomes

  1. The safety of rDEN2Δ30-7169 in Dengue immune participants

    To evaluate the safety of rDEN2Δ30-7169 in dengue-immune participants as assessed by the frequency of virus-related adverse events (AEs), graded by severity.

    Time frame: Day 0 -60 after virus challenge

07

Study locations

No study locations are listed for this record.

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References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Start is estimated for Sep 2025; primary completion for Jun 2026, 9 months later.

Of 22 phase 1 interventional studies under Dengue, half reached primary completion within 14 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 18. This study's planned 9 months is below that.

How these figures are worked out, and which studies are left out of them.

Registered
Apr 1, 2025
First posted
Apr 3, 2025
StartEst.
Sep 2025
Primary completionEst.
Jun 2026
CompletionEst.
Sep 2028
Last update
Apr 3, 2025
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Apr 3, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06908018
Lead sponsor
Mahidol University
Responsible party
Sponsor
First posted
Apr 3, 2025
Start date
Sep 2025 (estimated)
Primary completion
Jun 2026 (estimated)
Completion
Sep 2028 (estimated)
Last update
Apr 3, 2025

Study contacts

Panisadee Avirutnan, M.D., Ph.D.
Contact
panisadee.avi@mahidol.edu
+6624196667-70

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.

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