An Early Phase 1 interventional study of rDEN2Δ30-7169 in Dengue, sponsored by Mahidol University. Not yet recruiting at 1 site in Thailand. Open to participants aged 18 Years to 30 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-07-27.
Sponsored by Mahidol University · Early Phase 1, Interventional, and Other
Dengue viral infection and dengue hemorrhagic fever (DHF) are important emerging health problems worldwide. Several candidate dengue vaccines are currently in different stages of development but CYD is the only licensed vaccine currently available. Although this vaccine can induce neutralizing antibodies against all four DENV serotypes, the vaccine showed enhanced hospitalization in recipients who were dengue-naïve before vaccination. The long-term safety assessment of the vaccine in endemic regions demonstrated that the risk of hospitalization in year 3 of vaccination was higher in the vaccine group especially among recipients under 9 years of age with a relative risk of 1.58 [95% CI, 0.83 to 3.02].
Surrogate animal models are not good models to see whether the vaccine or therapeutic is able to be tested in clinical trials since animals do not develop symptoms of infection as in humans. The ADE phenomenon and the lack of known correlates of protection in animal models are still the major problems and challenges in the development of an effective dengue vaccine and make it difficult to identify candidate vaccines. The efficacy and safety situation of CYD also highlights the requirement of verification of candidate vaccines before performing clinical trials with a large number of participants.
The controlled human infection model, therefore, has been proposed to pre-evaluate candidate vaccines before moving into larger clinical trials. It has been previously used for several infectious diseases i.e., malaria, norovirus, influenza, cholera, Campylobacter, and Shigella, to accelerate vaccine or therapeutic development. For dengue, two controlled dengue human infection models (DHIM) have been established for vaccine testing and evaluation of therapeutics in a dengue naïve population in the USA. Although it has been proved useful for studies of dengue in naïve individuals, it is necessary to set up DHIM in endemic regions like Thailand as more than 90% of the population has been previously exposed to the virus and, importantly, host immune status prior to the introduction of viruses can influence clinical outcomes and vaccine efficacy. It will also be very challenging in terms of safety concerns since having pre-existing immune responses to natural DENV infection is a risk factor for severe dengue. The establishment of DHIM will not only allow a small-scale demonstration for safety and efficacy of vaccines or therapeutics which can appropriately guide the design of phase III to be more cost-effective but it will also allow the investigation of immune correlates of protection and determination of factors correlated with disease protection and pathogenesis as clinical endpoints can be closely followed up in all participants.
Safety, Virological and Immunological Assessment of the Controlled Dengue Human Infection Model in Thailand (DHIT) is proposed to challenge the live attenuated dengue virus serotype 2, rDEN2Δ30-7169, in 5 flavivirus naïve participants recruited from Bangkok, Thailand, and aims to assess the safety, viremia, NS1 antigenemia profile, and immunogenicity of the challenge virus in the volunteers.
In addition, this DHIT project will vaccinated all 5 participants with Dengvaxia® after inoculation with the challenge virus to reduce the risk of severe disease of dengue in the future. Blood collection will be obtained after each vaccination to assess virological and immunological profiles. Active and passive surveillance will be set up to monitor for dengue infection after vaccination. The overall study period from administration of live attenuated virus until last follow-up visit is 38 months.
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 →Mahidol University is the lead sponsor of 747 studies on the registry; 119 are open to participants now.
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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.
Display flavivirus immunity profile defined by the standard PRNT 50% (PRNT50) as follows: flavivirus naïve is defined as the PRNT50 titer against
Exclusion Criteria:
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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 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 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.
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.
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.
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.
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.
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.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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 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.
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.
Biological: rDEN2Δ30-7169
rDEN2Δ30-7169 will be inoculated at Study Day 0. After 6 months of the inoculation, the participants will be vaccinated with Dengvaxia® until completion of 3 doses with 6-month interval between each dose.
The safety of rDEN2Δ30-7169 in flavivirus naïve participants
Occurrence of local and general adverse events (AEs) and serious adverse events (SAEs)
Time frame: 21 Days
The frequency of viremia following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Proportion of number of volunteer with detectable virus genome assessed by nested RT-PCR, real time RT-PCR and virus culture after administration of DENV2Δ30-7169
Time frame: 180 Days
The quantity of viral genome following administration with rDEN2Δ30-7169 in flavivirus naïve participants
The quantity of viral genome (copies/mL) assessed by nested RT-PCR, real time RT-PCR and virus culture after administration of DENV2Δ30-7169
Time frame: 180 Days
The duration of viremia following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Days of detectable virus genome assessed by nested RT-PCR, real time RT-PCR and virus culture after administration of DENV2Δ30-7169
Time frame: 180 Days
The frequency of viremia following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Proportion of number of volunteer with detectable infectious activity assessed by nested RT-PCR, real time RT-PCR and virus culture after administration of DENV2Δ30-7169
Time frame: 180 Days
The quantity of infectious activity following administration with rDEN2Δ30-7169 in flavivirus naïve participants
The quantity of infectious activity (FFU/mL) assessed by nested RT-PCR, real time RT-PCR and virus culture after administration of DENV2Δ30-7169
Time frame: 180 Days
The duration of infectious activity following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Days of detectable infectious activity assessed by nested RT-PCR, real time RT-PCR and virus culture after administration of DENV2Δ30-7169
Time frame: 180 Days
The frequency of NS1 antigenemia following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Proportion of number of volunteer with detectable NS1 antigen after administration of DENV2Δ30-7169
Time frame: 180 Days
The quantity of NS1 antigenemia following administration with rDEN2Δ30-7169 in flavivirus naïve participants
The quantity of NS1 antigenemia (ng/mL) after administration of DENV2Δ30-7169
Time frame: 180 Days
The duration of NS1 antigenemia following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Days of detectable NS1 antigen after administration of DENV2Δ30-7169
Time frame: 180 Days
The immunogenicity of rDEN2Δ30-7169 in Thai flavivirus naïve participants
Levels of neutralizing antibodies (NT50) as measured by PRNT to dengue virus after administration with rDEN2Δ30-7169
Time frame: 180 Days
Measurement of levels of anti-dengue virion-IgM/IgG antibodies following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Levels of anti-dengue virion-IgM/IgG antibodies (titer) as measured by ELISA following administration with rDEN2Δ30-7169 in flavivirus naïve participants
Time frame: 180 Days
The cellular immune responses including dengue virus specific B cells and NS3 peptides specific T cells to all four DENV serotypes following administration of rDEN2Δ30-7169 in Thai flavivirus naïve participants
The frequency of dengue virus specific B cells and NS3 peptides specific T cells (percentage of cells/total lymphocytes) to all four DENV serotypes following administration of rDEN2Δ30-7169 in Thai flavivirus naïve participants
Time frame: Study Day 0-60
To measure anti-dengue virion-IgM/IgG antibodies following vaccination with Dengvaxia®
Levels of anti-dengue virion-IgM/IgG antibodies (titer) as measured by ELISA following vaccination with Dengvaxia®
Time frame: Study Day 194-1140
The immunogenicity following vaccination with Dengvaxia®
Levels of neutralizing antibodies (NT50) as measured by PRNT to dengue virus following vaccination with Dengvaxia®
Time frame: Study Day 194-1140
The frequency of viremia in oral fluid specimens following administration with rDEN2Δ30-7169
Proportion of number of volunteer with viremia as assessed by RT-PCR oral fluid specimens following administration with rDEN2Δ30-7169 and vaccination with Dengvaxia®
Time frame: Study Day 0-600
The quantity of viremia in oral fluid specimens following administration with rDEN2Δ30-7169
The quantity of viremia (copies/mL) as assessed by RT-PCR oral fluid specimens following administration with rDEN2Δ30-7169 and vaccination with Dengvaxia®
Time frame: Study Day 0-600
The duration (days) of viremia in oral fluid specimens following administration with rDEN2Δ30-7169
Days of viremia as assessed by RT-PCR oral fluid specimens following administration with rDEN2Δ30-7169 and vaccination with Dengvaxia®
Time frame: Study Day 0-600
Anti-NS1 antibodies and anti-dengue IgM, IgG, IgG1, IgA antibodies levels in oral fluid specimens following administration with rDEN2Δ30-7169 and vaccination with Dengvaxia® in Thai flavivirus naïve participants
Levels of anti-NS1 antibodies and anti-dengue IgM, IgG, IgG1, IgA antibodies (unit) as measured by ELISA in oral fluid specimens following administration with rDEN2Δ30-7169 and vaccination with Dengvaxia® in Thai flavivirus naïve participants
Time frame: Study Day 0-600
This study is not yet recruiting, as verified in Jul 2022. You cannot join it, but the record below documents what was studied.
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