MalariaSG6NCT04478370
Characterizing Humoral Immune Response to Mosquito Bites
A study testing Mosquito bites in people with Malaria and Dengue, run by University of Oxford at 1 site in Thailand.
Trial summary
The characteristics of the humoral response directed against mosquito saliva antigens are not known precisely. This is a major limitation for using immunological markers as an outcome in epidemiological trials and as an indicator for operational deployment of interventions. Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- What is being tested?
- Mosquito bites
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 147 participants
- Where
- 1 siteThailand
- Study dates
- 21 Jan 2021to 23 Jul 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy male or female participant judged by a responsible physician with no abnormality identified on a medical evaluation;
- Thai, Burmese or Karen ethnicity;
- Aged ≥ 18 to <60 years old;
- Living in Mae Sot city for the last 12 months;
- Willing to participate in the activity and able to give informed consent for participating in the study;
- Able to tolerate direct mosquito exposure.
Who cannot join
- History of travel in a malaria endemic are (rural village) in the last 12 months, or plan to do so during the study;
- Medication or condition deemed to interfere with the outcome measure by a responsible physician;
- Moderate and severe anemia (haemoglobin concentration less than 110 g/L of blood);
- Hypersensitivity or anaphylaxis to mosquito bites;
- Pregnant women
Trial locations and contacts
1 site in 1 country.
Thailand1 site
Shoklo Malaria Research unit (SMRU)
Mae Sot, Changwat Tak, 63110
About this study
Official title: Characterizing the Humoral Immune Response Against Salivary Antigens of Southeast Asian Mosquito Vectors of Malaria and Dengue With a Human Challenge Model
The characteristics of the humoral response directed against mosquito saliva antigens are not known precisely. This is a major limitation for using immunological markers as an outcome in epidemiological trials and as an indicator for operational deployment of interventions. Recent advances in the assembly of the genome of some Anopheles and Aedes mosquito vector species has facilitated the identification of new candidate peptides in silico, using the sequences of orthologous salivary gland proteins and B-cell prediction algorithms. The objective of this study is to assess the humoral immune response directed against candidate peptides following controlled exposure to laboratory-adapted colonies of An. minimus, An. maculatus and An. dirus, Ae. aegypti and Ae. albopictus.
This research will provide essential information to identify and validate immunological markers of human exposure to malaria and dengue mosquito vectors in Southeast Asia. Immunological markers would be useful to understand transmission dynamics and predict the risk of transmission as part of a surveillance system, and to assess the efficacy of vector-control interventions in entomological trials or during operational deployment of interventions in the region.
Read the detailed description
This study is a human challenge model with five arms corresponding to controlled exposure to bites of uninfected laboratory-adapted colonies of Anopheles minimus, An. maculatus, An. dirus, Aedes. aegypti or Ae. albopictus. Following screening and eligibility assessment, 150 participants will be enrolled in the study using a block-randomized design stratified on the mosquito species and number of bites (35 or 305 bites in total) such as to constitute 10 groups of 15 individuals for each of the study condition. Participants will be in the study for 112 days. The baseline will consist of 2 visits over 2 weeks (day 0 and day 7).
In the low-exposure groups, participants will be exposed to 5 mosquito bites at weekly intervals from day 14 to day 56 (seven challenges with 5 mosquito bites/challenge over six weeks, yielding a total of 35 mosquito bites). In the high-exposure group, participants will be exposed to 5 mosquito bites on day 14 and then to 50 mosquito bites at weekly intervals from day 21 to day 56 (one challenge with 5 mosquito bites and six challenges with 50 mosquito bites/challenge over 6 weeks, yielding a total of 305 mosquito bites).
The number of bites and modalities of the follow up used in this study were chosen based on previous entomological investigation conducted in this area, published reports of human challenge with mosquito bites and current knowledge on the characteristic of the humoral response against saliva antigens. Both immediate and delayed skin reactions will be recorded after day 14 and day 21 challenges, requiring additional visits at day 15 and day 22. Participants with hypersensitivity to mosquito bites will be withdrawn from the study. Both capillary and venous blood samples will be collected weekly from each study participant. Eighteen venous blood samples will be collected including one sample of 2 mL drawn during screening visit, 14 samples of 8.6 mL during visits 2, 3, 6, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18 and 19, and 3 samples of 18.6 mL during visits 4, 13 and 20 (178.2 mL of venous blood per participant in total). Seventeen dry blood spot (DBS) samples will be made from of 300 μL of capillary blood collected during visits 2, 3, 4, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 and 20 (5.1 mL of capillary blood per participant in total).
Candidate peptides will be identified in silico using publicly available genomes sequences and B-cell epitope prediction algorithms. The kinetic of antibody titers against candidate biomarkers will be assessed by enzyme-linked immunosorbent assay (ELISA) and mesoscale screening performed with serum and DBS specimens. Briefly, the positivity threshold of the assay will be determined using reference sera specimens from individuals not exposed to mosquito bites, as described previously. The ELISA signal measured in 60 reference sera obtained from unexposed individuals (30 Thai sera obtained from the Thai Red Cross and 30 Australian sera obtained from the Burnet Institute) will be used to define the positivity threshold of the assay. The positivity threshold of the assay will be defined as three standard deviation (SD) above the mean optic density (ΔOD) measured for the unexposed control population. A test in the study population with a ΔOD above this cut-off will be considered positive (i.e. an immune response). The specific antibody titer of study samples will be determined by performing serial dilution experiments. Serial dilution will be made from study samples and the ΔOD will be determined for each dilution. The antibody titer will be defined as the highest dilution giving a positive signal. Results obtained with DBS and serum specimens will be compared in order to assess the feasibility of using DBS samples to monitor exposure to bites of mosquitoes during epidemiological studies. Serum specimens collected during visits 4 (baseline), 13 (early after the end of exposure) and 20 (post-exposure) will also be analysed with immuno-proteomic approach (2D gel electrophoresis of salivary gland protein extracts, Western blot and mass spectrometry) yielding additional information on the antigenic properties of mosquito salivary gland proteome.
Planned Sample Size: 150 participants followed-up for 16 weeks
Participant Identification:
Study participants are defined as healthy participants aged between 18 and 60 years old and willing to participate in the study. This study will take place at the Shoklo Malaria Research Unit (SMRU) research centre in Mae Sot.
This study was funded by the Wellcome Trust under the core funding (#220211).
- Being tested
- Mosquito bites
- Keywords
- Mosquito bites, Biomarkers, Malaria vectors, Dengue vectors
- Medical subject headings
- Malaria, Dengue
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Mosquito bitesBiological
Participants will be exposed to mosquito bites.
For the low-dose challenge, five 5 to 7-day-old nulliparous female imagoes (i.e. that have never blood fed before) will be introduced individual into 50 mL plastic tube covered with netting material.
For high-dose challenge, 47 mosquitoes will be split into four plastic cups of 10 cm in diameter covered with netting material (three cups with 12 mosquitoes and one cup with 11 mosquitoes), and 3 mosquitoes will be introduced individually into 50 mL plastic tubes.
Mosquito bites administered on participant's arm will be used to assess immediate and delayed skin reactions. Immediate and delayed skin reactions will be recorded respectively 20-30 min and 24-36 hours after the day 14 and day 21 challenges, requiring additional visits at day 15 and 22.
| Study group | Role | What they receive |
|---|---|---|
| An. minimus | Experimental | This arm will be divided into 2 groups; the low-exposure groups and the high-exposure group.
In the low-exposure group, participants will be exposed to 5 mosquito bites at weekly intervals from day 14 to day 56 (seven challenges with 5 mosquito bites/challenge over six weeks, yielding a total of 35 mosquito bites).
In the high-exposure group, participants will be exposed to 5 mosquito bites on day 14 and then to 50 mosquito bites at weekly intervals from day 21 to day 56 (one challenge with 5 mosquito bites and six challenges with 50 mosquito bites/challenge over 6 weeks, yielding a total of 305 mosquito bites). Receives: Biological: Mosquito bites |
| An. maculatus | Experimental | Same as above Receives: Biological: Mosquito bites |
| An. dirus | Experimental | Same as above Receives: Biological: Mosquito bites |
| Ae. aegypti | Experimental | Same as above Receives: Biological: Mosquito bites |
| Ae. albopictus | Experimental | Same as above Receives: Biological: Mosquito bites |
What is being measured
The primary outcome is the main question the study is designed to answer.
Levels of specific antibody titers against candidate peptides before and during repeated exposure to laboratory-reared mosquito bites determined by ELISA and mesoscale screening.
Measured: baseline through day 112
Kinetics of specific antibody titers against candidate peptides before and during repeated exposure to laboratory-reared mosquito bites determined by ELISA and mesoscale screening.
Measured: baseline through day 112
Sequence of saliva antigens determined with an immuno-proteomic method (2D gel electrophoresis of salivary gland protein extracts, Western blot and mass spectrometry).
Measured: Day 14 through day 112
Secondary outcomes (2)
Comparison of the antibody titers determined in subgroups corresponding to different level of exposure.
Measured: Day 0, 7 (baseline), 14, 21, 28, 35, 42, 49, 56 (exposure period), 63, 70, 77, 84, 91, 98, 105 and 112 (post-exposure period).
Comparison of the antibody titers determined in DBS and venous blood samples.
Measured: Day 0, 7 (baseline), 14, 21, 28, 35, 42, 49, 56 (exposure period), 63, 70, 77, 84, 91, 98, 105 and 112 (post-exposure period).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 Jul 2020
- Study start21 Jan 2021
- Primary completion23 Jul 2025
- Study completion23 Jul 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for MalariaStudies of the same condition, open and under way.
- More trials run by University of OxfordThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This study is a human challenge model with five arms corresponding to controlled exposure to bites of uninfected laboratory-adapted colonies of Anopheles minimus, An. maculatus, An. dirus, Aedes. aegypti or Ae. albopictus.
- Masking
- None (open label)
- Enrolment
- 147 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Oxford
- Sponsor type
- University, hospital or other
- Collaborators
- National Health and Medical Research Council, Australia, Burnet Institute, Agency for Science, Technology and Research
- Responsible party
- Sponsor
- Investigators
- François Nosten, Principal investigator, Shoklo Malaria Research Unit
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04478370
- Sponsor's protocol ID
- MAL19009
- Acronym
- SG6
- Status last verified
- Aug 2025
- First submitted
- 29 Jun 2020
- Last updated
- 3 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Sawasdichai S, Chaumeau V, Kearney E, Wasisakun P, Simpson JA, Price DJ, Chotirat S, Renia L, Bergmann-Leitner E, Fowkes F, Nosten F. Characterizing antibody responses to mosquito salivary antigens of the Southeast Asian vectors of malaria and dengue with a human challenge model of controlled exposure: a protocol. Wellcome Open Res. 2023 Jul 11;8:135. doi: 10.12688/wellcomeopenres.19049.2. eCollection 2023.
PubMed 37456919Chaumeau V, Kearney EA, Wasisakun P, Sawasdichai S, Aung AA, Agius PA, Min TH, da Silva Goncalves D, O'Flaherty K, Rouers A, Aryalamloed S, Htoo GN, Sue MP, Tha NM, Chanida N, Gornsawun G, Chotirat S, Simpson JA, Renia L, Nosten F, Fowkes FJI. Assessment of antibody responses to Anopheles SG6-P1 and Aedes N-term 34 kDa salivary peptides: a randomised human-challenge trial of controlled exposures to vector bites. BMC Med. 2026 Mar 2;24(1):203. doi: 10.1186/s12916-026-04732-z.
PubMed 41765941
Study at a glance
From the registry record, last updated by the sponsor on 3 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Characterizing the Humoral Immune Response Against Salivary Antigens of Southeast Asian Mosquito Vectors of Malaria and Dengue With a Human Challenge Model
- ClinicalTrials.gov ID
- NCT04478370
- Acronym / sponsor ID
- SG6 / MAL19009
- Keywords
- Mosquito bites, Biomarkers, Malaria vectors, Dengue vectors
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 147 participants (actual)
- Lead sponsor
- University of OxfordUniversity, hospital or other
- Collaborators
- National Health and Medical Research Council, Australia, Burnet Institute, Agency for Science, Technology and Research
- Study start
- 21 Jan 2021 (actual)
- Primary completion
- 23 Jul 2025 (actual)
- Study completion
- 23 Jul 2025 (actual)
- First posted
- 20 Jul 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The characteristics of the humoral response directed against mosquito saliva antigens are not known precisely. This is a major limitation for using immunological markers as an outcome in epidemiological trials and as an indicator for operational deployment of interventions. Recent advances in the assembly of the genome of some Anopheles and Aedes mosquito vector species has facilitated the identification of new candidate peptides in silico, using the sequences of orthologous salivary gland proteins and B-cell prediction algorithms. The objective of this study is to assess the humoral immune response directed against candidate peptides following controlled exposure to laboratory-adapted colonies of An. minimus, An. maculatus and An. dirus, Ae. aegypti and Ae. albopictus.
This research will provide essential information to identify and validate immunological markers of human exposure to malaria and dengue mosquito vectors in Southeast Asia. Immunological markers would be useful to understand transmission dynamics and predict the risk of transmission as part of a surveillance system, and to assess the efficacy of vector-control interventions in entomological trials or during operational deployment of interventions in the region.
Detailed description
This study is a human challenge model with five arms corresponding to controlled exposure to bites of uninfected laboratory-adapted colonies of Anopheles minimus, An. maculatus, An. dirus, Aedes. aegypti or Ae. albopictus. Following screening and eligibility assessment, 150 participants will be enrolled in the study using a block-randomized design stratified on the mosquito species and number of bites (35 or 305 bites in total) such as to constitute 10 groups of 15 individuals for each of the study condition. Participants will be in the study for 112 days. The baseline will consist of 2 visits over 2 weeks (day 0 and day 7).
In the low-exposure groups, participants will be exposed to 5 mosquito bites at weekly intervals from day 14 to day 56 (seven challenges with 5 mosquito bites/challenge over six weeks, yielding a total of 35 mosquito bites). In the high-exposure group, participants will be exposed to 5 mosquito bites on day 14 and then to 50 mosquito bites at weekly intervals from day 21 to day 56 (one challenge with 5 mosquito bites and six challenges with 50 mosquito bites/challenge over 6 weeks, yielding a total of 305 mosquito bites).
The number of bites and modalities of the follow up used in this study were chosen based on previous entomological investigation conducted in this area, published reports of human challenge with mosquito bites and current knowledge on the characteristic of the humoral response against saliva antigens. Both immediate and delayed skin reactions will be recorded after day 14 and day 21 challenges, requiring additional visits at day 15 and day 22. Participants with hypersensitivity to mosquito bites will be withdrawn from the study. Both capillary and venous blood samples will be collected weekly from each study participant. Eighteen venous blood samples will be collected including one sample of 2 mL drawn during screening visit, 14 samples of 8.6 mL during visits 2, 3, 6, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18 and 19, and 3 samples of 18.6 mL during visits 4, 13 and 20 (178.2 mL of venous blood per participant in total). Seventeen dry blood spot (DBS) samples will be made from of 300 μL of capillary blood collected during visits 2, 3, 4, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 and 20 (5.1 mL of capillary blood per participant in total).
Candidate peptides will be identified in silico using publicly available genomes sequences and B-cell epitope prediction algorithms. The kinetic of antibody titers against candidate biomarkers will be assessed by enzyme-linked immunosorbent assay (ELISA) and mesoscale screening performed with serum and DBS specimens. Briefly, the positivity threshold of the assay will be determined using reference sera specimens from individuals not exposed to mosquito bites, as described previously. The ELISA signal measured in 60 reference sera obtained from unexposed individuals (30 Thai sera obtained from the Thai Red Cross and 30 Australian sera obtained from the Burnet Institute) will be used to define the positivity threshold of the assay. The positivity threshold of the assay will be defined as three standard deviation (SD) above the mean optic density (ΔOD) measured for the unexposed control population. A test in the study population with a ΔOD above this cut-off will be considered positive (i.e. an immune response). The specific antibody titer of study samples will be determined by performing serial dilution experiments. Serial dilution will be made from study samples and the ΔOD will be determined for each dilution. The antibody titer will be defined as the highest dilution giving a positive signal. Results obtained with DBS and serum specimens will be compared in order to assess the feasibility of using DBS samples to monitor exposure to bites of mosquitoes during epidemiological studies. Serum specimens collected during visits 4 (baseline), 13 (early after the end of exposure) and 20 (post-exposure) will also be analysed with immuno-proteomic approach (2D gel electrophoresis of salivary gland protein extracts, Western blot and mass spectrometry) yielding additional information on the antigenic properties of mosquito salivary gland proteome.
Planned Sample Size: 150 participants followed-up for 16 weeks
Participant Identification:
Study participants are defined as healthy participants aged between 18 and 60 years old and willing to participate in the study. This study will take place at the Shoklo Malaria Research Unit (SMRU) research centre in Mae Sot.
This study was funded by the Wellcome Trust under the core funding (#220211).
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 5
- Model description
- This study is a human challenge model with five arms corresponding to controlled exposure to bites of uninfected laboratory-adapted colonies of Anopheles minimus, An. maculatus, An. dirus, Aedes. aegypti or Ae. albopictus.
| Arm | Type | Receives |
|---|---|---|
| An. minimus | Experimental | Biological: Mosquito bitesThis arm will be divided into 2 groups; the low-exposure groups and the high-exposure group. In the low-exposure group, participants will be exposed to 5 mosquito bites at weekly intervals from day 14 to day 56 (seven challenges with 5 mosquito bites/challenge over six weeks, yielding a total of 35 mosquito bites). In the high-exposure group, participants will be exposed to 5 mosquito bites on day 14 and then to 50 mosquito bites at weekly intervals from day 21 to day 56 (one challenge with 5 mosquito bites and six challenges with 50 mosquito bites/challenge over 6 weeks, yielding a total of 305 mosquito bites). |
| An. maculatus | Experimental | Biological: Mosquito bitesSame as above |
| An. dirus | Experimental | Biological: Mosquito bitesSame as above |
| Ae. aegypti | Experimental | Biological: Mosquito bitesSame as above |
| Ae. albopictus | Experimental | Biological: Mosquito bitesSame as above |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (6 listed)
- Healthy male or female participant judged by a responsible physician with no abnormality identified on a medical evaluation;
- Thai, Burmese or Karen ethnicity;
- Aged ≥ 18 to <60 years old;
- Living in Mae Sot city for the last 12 months;
- Willing to participate in the activity and able to give informed consent for participating in the study;
Key exclusion criteria (5 listed)
- History of travel in a malaria endemic are (rural village) in the last 12 months, or plan to do so during the study;
- Medication or condition deemed to interfere with the outcome measure by a responsible physician;
- Moderate and severe anemia (haemoglobin concentration less than 110 g/L of blood);
- Hypersensitivity or anaphylaxis to mosquito bites;
- Pregnant women
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Mosquito bitesParticipants will be exposed to mosquito bites. For the low-dose challenge, five 5 to 7-day-old nulliparous female imagoes (i.e. that have never blood fed before) will be introduced individual into 50 mL plastic tube covered with netting material. For high-dose challenge, 47 mosquitoes will be split into four plastic cups of 10 cm in diameter covered with netting material (three cups with 12 mosquitoes and one cup with 11 mosquitoes), and 3 mosquitoes will be introduced individually into 50 mL plastic tubes. Mosquito bites administered on participant's arm will be used to assess immediate and delayed skin reactions. Immediate and delayed skin reactions will be recorded respectively 20-30 min and 24-36 hours after the day 14 and day 21 challenges, requiring additional visits at day 15 and 22. | Biological | Ae. aegypti, Ae. albopictus, An. dirus, An. maculatus, An. minimus |
Primary outcome
Levels of specific antibody titers against candidate peptides before and during repeated exposure to laboratory-reared mosquito bites determined by ELISA and mesoscale screening.
Time frame: baseline through day 112
Kinetics of specific antibody titers against candidate peptides before and during repeated exposure to laboratory-reared mosquito bites determined by ELISA and mesoscale screening.
Time frame: baseline through day 112
Sequence of saliva antigens determined with an immuno-proteomic method (2D gel electrophoresis of salivary gland protein extracts, Western blot and mass spectrometry).
Time frame: Day 14 through day 112
2 secondary outcomes
Comparison of the antibody titers determined in subgroups corresponding to different level of exposure.
Time frame: Day 0, 7 (baseline), 14, 21, 28, 35, 42, 49, 56 (exposure period), 63, 70, 77, 84, 91, 98, 105 and 112 (post-exposure period).
Comparison of the antibody titers determined in DBS and venous blood samples.
Time frame: Day 0, 7 (baseline), 14, 21, 28, 35, 42, 49, 56 (exposure period), 63, 70, 77, 84, 91, 98, 105 and 112 (post-exposure period).
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Feb 2026.
- Results publication: PubMed 37456919Sawasdichai S, Chaumeau V, Kearney E, Wasisakun P, Simpson JA, Price DJ, Chotirat S, Renia L, Bergmann-Leitner E, Fowkes F, Nosten F. Characterizing antibody responses to mosquito salivary antigens of the Southeast Asian vectors of malaria and dengue with a human challenge model of controlled exposure: a protocol. Wellcome Open Res. 2023 Jul 11;8:135. doi: 10.12688/wellcomeopenres.19049.2. eCollection 2023.
- Derived from this study: PubMed 41765941Chaumeau V, Kearney EA, Wasisakun P, Sawasdichai S, Aung AA, Agius PA, Min TH, da Silva Goncalves D, O'Flaherty K, Rouers A, Aryalamloed S, Htoo GN, Sue MP, Tha NM, Chanida N, Gornsawun G, Chotirat S, Simpson JA, Renia L, Nosten F, Fowkes FJI. Assessment of antibody responses to Anopheles SG6-P1 and Aedes N-term 34 kDa salivary peptides: a randomised human-challenge trial of controlled exposures to vector bites. BMC Med. 2026 Mar 2;24(1):203. doi: 10.1186/s12916-026-04732-z.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
François Nosten principal investigator
Shoklo Malaria Research Unit
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Mosquito bites in people with Malaria and Dengue, run by University of Oxford at 1 site in Thailand.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 3 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Thailand. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Levels of specific antibody titers against candidate peptides before and during repeated exposure to laboratory-reared mosquito bites determined by ELISA and mesoscale screening. (time frame: baseline through day 112). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04478370, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Feb 2026.