An interventional study of GMP-produced rDEN3delta30 virus in Dengue, sponsored by Tan Tock Seng Hospital. Active, not recruiting at 1 site in Singapore. Open to participants aged 21 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-16.
Sponsored by Tan Tock Seng Hospital · Not applicable, Interventional, and Other
This study aims to conduct a safe human infection challenge using an attenuated serotype DEN3 dengue virus in adult volunteers. The clinical, viral and immune response characteristics of the model will be analysed to understand the pathophysiology of dengue fever. This data will be used to inform future studies, including a planned follow up study (DEN-CHIM-02) which will investigate the efficacy of an investigational dengue vaccine at protecting against DEN3 infection.
Study conditions that result in a safe, reproducible infection in ≥80% of research participants (attack rate) with the DEN3 challenge agent have been identified during studies conducted by collaborators in the US. This includes the inoculum dose, safety monitoring, and necessary participant pre-screening to exclude prior Orthoflavivrus infection or vaccinations.
Study objectives are to:
Dengue fever is a mosquito-transmitted infection, with an escalating geographic distribution and disease burden because of factors including climate change, urbanisation and globalisation. Despite ongoing and often intensive vector control efforts implemented in many endemic countries, the incidence of dengue has increased thirty-fold worldwide over the past half-century, establishing it as the most rapidly spreading vector-borne disease. The rising burden of disease from dengue is further compounded by the absence of specific antiviral treatments, and the limitations of currently available vaccines.
In light of these challenges, innovative strategies to enhance the understanding of dengue and accelerate the development of effective countermeasures are urgently needed. Controlled human infection (CHI) studies have emerged as a valuable tool in this endeavour, offering a unique platform for investigating the natural history of infectious diseases and evaluating the potential of novel interventions.
CHI studies involve the deliberate inoculation of human volunteers with an infectious agent such as a virus, bacteria, or parasite. The strength of this study design is a result of their highly controlled nature, whereby carefully selected volunteers are exposed to standardised amounts of a well-characterised infectious agent. This enables exact longitudinal measurement of challenge agent replication kinetics, infectious shedding, immunological responses and clinical features, and contrasts with what is achievable through field trials of natural infection, including household contact studies. By inoculating all study participants with the same agent at the same dose and under the same conditions, confounding by strain, dose, and exposure is controlled. Host factors associated with inter-individual differences in clinical outcome and the effect of interventions can then be robustly inferred, along with the ability to connect detailed longitudinal data to the earliest time points after exposure, including prior to the onset of symptoms.
Singapore, an equatorial city-state, is highly endemic for dengue, with the co-circulation of all four serotypes. The country boasts a well-established research infrastructure and considerable expertise in infectious diseases at institutions like NCID. Singapore also has a globally recognized vector control program and maintains extensive dengue surveillance data, providing a rich context for studying the disease. The strong research infrastructure and expertise at NCID, coupled with Singapore's commitment to public health and its history of effective disease surveillance and control, create a conducive environment for conducting high-quality and impactful dengue CHI studies.
Findings from CHI studies conducted in Singapore are likely to be highly relevant to other endemic areas in Southeast Asia and globally. The specific dengue serotype dynamics in Singapore, including recent switches involving DEN1 and DEN3, make research on these serotypes particularly timely. Furthermore, Singapore has observed a shift in the average age of dengue patients towards older adults, who may be at higher risk of severe disease, making research in this context especially important.
By developing a dengue controlled human infection model in Singapore through the DEN-CHIM-01 study the investigators intend to enable:
The DEN-CHIM-01 study will use the optimised conditions established by collaborators in the US to conduct a GMP rDEN3delta30 challenge study in seronegative volunteers. This study aims to investigate in the Singapore context the clinical, virologic and immunologic features of DEN3 infection and what immune, transcriptomic and genomic markers correlate with symptomology, viral kinetics and the immune response.
The DEN-CHIM-01 study forms part of a wider programme of work in Singapore, both in dengue fever and using CHI studies as an experimental model to advance the development of therapeutics and vaccines. Experience from the Sing-CoV controlled human infection study (PI: A/Prof Barnaby Young) has informed development of this protocol, and agreements for sharing of samples and data with scientific collaborators are in place.
The DEN-CHIM-01 is a critical first step to conducting a follow up pilot clinical trial, DEN-CHIM-02, funded by the same grant. In DEN-CHIM-02 the investigators plan to investigate the efficacy of a dengue vaccine at protecting against challenge with rDEN3delta30.
283 studies on the registry are indexed under Dengue; 44 are open to participants now.
This study's planned enrollment of 5 is below the median of 132 across 197 interventional studies indexed under Dengue.
Browse Dengue studies →Tan Tock Seng Hospital is the lead sponsor of 108 studies on the registry; 19 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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.
6b Male participants who are willing to use one of the contraception methods described in the study protocol, from the date of viral challenge, for 1 month. In addition to the contraceptive requirements above, male participants must agree not to donate sperm following discharge from quarantine until 1 month after the date of viral challenge.
7 In good health with no history of medical conditions (as described in Exclusion criteria) that would interfere with subject safety, as defined by medical history, physical examination and routine laboratory tests, , and Chest X-Ray and determined by the Investigator at an admission evaluation.
8 Willing and able to commit to participation in the study.
Exclusion Criteria:
Any of the following:
Positive , active/chronic or test. 10 Twelve-lead recording with clinically relevant abnormalities as judged by the study investigator.
11 Receipt of a within 60 days prior to the planned date of viral challenge, a non-live vaccine within 30 days prior to the planned date of viral challenge or intention to receive any vaccination(s) before the day 28 follow-up visit.
12 Previous receipt of a flavivirus vaccine (licensed or experimental). 13 Receipt of blood or blood products, or loss (including blood donations) of 550 mL or more of blood during the 3 months prior to the planned date of viral challenge or planned during the 3 months after the final visit.
14 Medications:
15 Participant is mentally or legally incapacitated in the opinion of the Investigator.
16 Females who:
18 Any other reason that the Investigator considered made the participant unsuitable to participate.
19 Presence of symptoms and/or fever (defined as participant presenting with a temperature reading of >37.9ºC) suggesting an infection at pre-challenge on Day 0.
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.
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.
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.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
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.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
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 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.
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.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GMP-produced rDEN3delta30 virus will be administered to participants via subcutaneous injection.
Other: GMP-produced rDEN3delta30 virus
The challenge virus used in DEN-CHIM-01 study (rDEN3delta30) is produced by the National Institutes of Health (NIH). The rDEN3delta30 strain has been tested in seronegative participants in two challenge studies and with two inoculum doses: 10\^3 and 10\^4 PFU. The wildtype parent (wildtype DEN3 strain) of the rDEN3Δ30 challenge agent was originally obtained from an infected patient in 1978, in Sleman, Yogyakarta, Indonesia. The Sleman/78 strain was a naturally occurring, partially attenuated dengue virus (DENV) suitable for development as a challenge agent. The NIH team made a contiguous 30-nucleotide deletion in the 3' untranslated region of the wildtype DENV genome and produced recombinant DENV via cDNA clone (rDEN3delta30).
Incidence of unsolicited Adverse Events (AEs) [Safety]
Number of unsolicited AEs
Time frame: From day of viral challenge (Day 0) to Day 28 follow-up visit
Severity of unsolicited AEs [Safety]
Grading severity of AEs is guided by the FDA Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials: Grade 1 (Mild), Grade 2 (Moderate), Grade 3 (Severe), Grade 4 (Potentially life threatening)
Time frame: From day of viral challenge (Day 0) to Day 28 follow-up visit
Incidence of Serious Adverse Events (SAEs) related to the viral challenge [Safety]
Number of SAEs. Whether an adverse event is serious is determined by the outcome resulting from the event. An SAE is any untoward medical occurrence that: * Results in death * Is life-threatening (immediate risk of death) * Requires inpatient hospitalization or prolongation of existing hospitalization * Results in persistent or significant disability/incapacity * Results in congenital anomaly/birth defect * Is a medically important event
Time frame: Day of viral challenge (Day 0) to Day 28 follow-up visit
Number of participants with lab confirmed infection [Infectivity]
Laboratory confirmed infection is defined as at least one quantifiable (greater than lower limit of quantification, ≥LLOQ) qPCR measurement of DENV from blood
Time frame: From day of viral challenge (Day 0) to discharge from quarantine (Day 10).
Incidence of symptomatic DENV infection
Number of participants with lab confirmed symptomatic DENV infection
Time frame: From day of viral challenge (Day 0) to 10 days post-inoculation
Peak viral load in serum samples measured by qPCR
Peak viral load of DENV as defined by the maximum viral load determined by qPCR measurements
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Duration of DENV viraemia measured by qCPR
Duration is defined as the day of first quantifiable viral detection until first confirmed undetectable assessment after their peak measure and after which no further virus is detected.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Incubation period of DENV in serum samples measured by qPCR
Incubation period is defined as the time from inoculation to the first quantifiable viral detection, and up to discharge from quarantine.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Peak viral load in serum samples measured using viral culture
Peak viral load of DENV as defined by the maximum viral load determined by plaque assay
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Duration of DENV viraemia measured using viral culture
Duration is defined as the day of first quantifiable viral detection until first confirmed undetectable assessment after their peak measure and after which no further virus is detected.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Incubation period of DENV in serum samples measured using viral culture
Incubation period is defined as the time from inoculation to the first quantifiable viral detection, and up to discharge from quarantine.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Peak viral load in serum samples measured using quantitative NS1 antigen
Peak viral load of DENV as defined by the maximum NS1 antigen measurement
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Duration of DENV viraemia measured using quantitative NS1 antigen
Duration is defined as the day of first quantifiable viral detection using quantitative NS1 antigen measurement until first confirmed undetectable assessment after their peak measure and after which no further virus is detected.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Incubation period of DENV in serum samples measured using quantitative NS1 antigen
Incubation period is defined as the time from inoculation to the first quantifiable viral detection using quantitative NS1 antigen measurements, and up to discharge from quarantine.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Severity of DENV-induced symptoms during quarantine period
Severity of DENV-related symptoms are reported and assessed by participants three times daily during quarantine using the Symptom Diary Card. Symptoms are graded on a scale of 0-3: * Grade 0: No symptoms. * Grade 1: Just noticeable. * Grade 2: Clearly bothersome from time to time but does not interfere with me doing my normal daily activities. * Grade 3: Quite bothersome most or all the time, and it stops me participating in activities. The sum total symptoms diary card score, peak symptoms diary card score and peak daily symptom score can be calculated.
Time frame: Day 1 post-viral challenge to Day 10.
Incidence of DENV illness
The incidence of: * Febrile illness (FI) * Symptomatic illness (SI) * Rash * Proportion of participants with Grade 3 symptoms on any occasion at any time from Day 0 to Day 14. * Proportion of participants with Grade 2 or higher symptoms on any occasion at any time from Day 0 to Day 14. * Proportion of participants with Grade 2 or higher Symptoms on two separate occasions at any time from Day 0 to Day 14. * Proportion of participants with any symptom (grade \>=1) on any occasion at any time from Day 0 to Day 14. * Proportion of participants with any symptom (grade \>=1) on two separate occasions at any time from Day 0 to Day 14.
Time frame: Day of inoculation (Day 0) to Day 14
Incidence of AEs as defined by clinically significant abnormal laboratory measurements during the quarantine period
Total number of clinically significant laboratory abnormalities during the quarantine period. Laboratory abnormalities associated with dengue fever (e.g.: elevated ALT, AST; decreased platelets) will be expected and will not be additionally captured as an AE unless deemed by an Investigator to be clinically significant.
Time frame: Day of inoculation (Day 0) to discharge from quarantine (Day 10)
Severity of AEs as defined by clinically significant abnormal laboratory measurements during the quarantine period
Severity of clinically significant laboratory abnormalities during the quarantine period. Grading severity of AEs is guided by the FDA Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials: Grade 1 (Mild), Grade 2 (Moderate), Grade 3 (Severe), Grade 4 (Potentially life threatening)
Time frame: Day of inoculation (Day 0) to discharge from quarantine (Day 10)
Incidence of concomitant medication usage
Total number of concomitant medications used after viral challenge
Time frame: Day 0 to Day 28 follow-up
Number of participants with laboratory confirmed infection from urine
Laboratory confirmed infection is defined as occurrence of at least one quantifiable (≥LLOQ) qPCR measurement
Time frame: Day 1 post-inoculation to discharge from quarantine (Day 10)
Peak viral load in urine measured by qPCR
Peak viral load of DENV as defined by the maximum viral load determined by qPCR measurements in urine
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Duration of detectable virus in urine measured by qPCR
Duration is defined as the time from first quantifiable viral detection until first confirmed undetectable assessment after their peak measure after which no further virus is detected or Day 14.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Incubation period of DENV in urine measured by qPCR
Incubation period is defined as the time from inoculation to the first quantifiable viral detection from inoculation and up to Day 10.
Time frame: Day 1 post-inoculation to Day 10 for uninfected participants or Day 14 for infected participants
Changes in antibody levels after rDEN3delta30 challenge
Assays performed on blood samples to assess humoral immunity / systems serology (for example: DENV neutralizing titres, ELISAs to DENV IgG, IgM, IgA, ADCC)
Time frame: Up to month 36 post-inoculation
Changes in protein levels after rDEN3delta30 challenge
Assays performed on blood samples to assess proteomic levels and changes (for example, cytokine and chemokines).
Time frame: Up to month 36 post-inoculation
Changes in cellular immunity after rDEN3delta30 challenge
Assays performed on blood samples include cellular cell quantification and quality of immunity (for example T and B cell frequencies, phenotypes, and functionality assays, ELISPOTS, ICS, cytokine/chemokine responses).
Time frame: Up to month 36 post-inoculation
Changes in transcriptome levels after rDEN3delta30 challenge
Assays performed on blood samples to measure transcriptome levels and changes (for example, RNAseq, single cell RNAseq, microarray, PCR)
Time frame: Up to month 36 post-inoculation
Changes in microbiome after rDEN3delta30 challenge
Assays performed on stool samples for microbiome analysis in relation to viral infection, disease, and susceptibility (e.g., PCR, NGS, 16s rRNA)
Time frame: Up to month 36 post-inoculation
Changes in levels of endothelial derived mediators after rDEN3delta30 challenge
Levels of endothelial derived mediators (e.g., prostacyclin, endothelin-1, nitric oxide) in the plasma will be measured.
Time frame: Up to month 24 post-inoculation
Plan to share: No — All study findings and documents will be regarded as confidential. The investigators and other study personnel must not disclose such information without prior written approval from the PI. Participant confidentiality will be strictly maintained to the extent possible under the law and local hospital policy. Identifiable information will be removed from any published data.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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