LeptospirosisPhase 4NCT07865156
These Studies That Evaluated the Efficacy of Antibiotics for Leptospirosis Treatment.
A Phase 4 study testing Doxycycline in people with Leptospirosis and Chemoprophylaxis, run by Chulalongkorn University.
Trial summary
The goal of this randomized controlled trial is to study antibiotic chemoprophylaxis to prevent leptospirosis of high-risk populations. The main question it aims to answer is : Does the efficacy of chemoprophylaxis regimens to prevent prevent leptospirosis? Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Leptospirosis, Chemoprophylaxis
- What is being tested?
- Doxycycline
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 1,000 participants
- Where
- No sites listed yet
- Study dates
- 1 Nov 2026to 31 Jan 2027
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
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 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- High-risk exposure typically refers to water or soil - particularly wet ground at workplace and/or contact with animal water reservoir
Who cannot join
- Body temperature higher than 38 °C
- Patients were confirmed to have leptospirosis within 3 months
- Pregnancy or breastfeeding
- Allergy to doxycycline
- Cirrhosis Child-Pugh C, acute hepatitis, persistent elevated liver enzymes AST/ALT > 3 times
- Doxycycline Interactions: phenytoin, carbamazepine, barbiturates, warfarin methotrexate, cyclosporin
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
Sasipha Tachaboon Excellence center for critical care nephrology contact
About this study
Official title: The Study of the Efficacy of Doxycycline for Chemoprophylaxis Acute Leptospirosis Infection During Rainy Season in Thailand
The goal of this randomized controlled trial is to study antibiotic chemoprophylaxis to prevent leptospirosis of high-risk populations.
The main question it aims to answer is : Does the efficacy of chemoprophylaxis regimens to prevent prevent leptospirosis?
- Conditions
- Leptospirosis, Chemoprophylaxis
- Being tested
- Doxycycline, Placebo
- Medical subject headings
- Leptospirosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
DoxycyclineDrug
Doxycycline 200 mg weekly
PlaceboDrug
Placebo
| Study group | Role | What they receive |
|---|---|---|
| Doxycycline 200 mg weekly dose | Experimental | Not described Receives: Drug: Doxycycline |
| Placebo | Placebo comparator | Not described Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Leptospira infection
Number of leptospirosis cases based on Polymerase Chain Reaction (PCR), culture and Microscopic Agglutination Test (MAT)
Measured: 1 month
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Oct 2026
- Study start1 Nov 2026 (estimated)
- Primary completion15 Dec 2026 (estimated)
- Study completion31 Jan 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for LeptospirosisStudies of the same condition, open and under way.
- More trials run by Chulalongkorn UniversityThe 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 4
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 1,000 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Chulalongkorn University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Nattachai Srisawat ,M.D., Chulalongkorn University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07865156
- Sponsor's protocol ID
- CREC087/68BR-MED30
- Status last verified
- Oct 2026
- First submitted
- 15 Jun 2026
- Last updated
- 8 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 8 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Study of the Efficacy of Doxycycline for Chemoprophylaxis Acute Leptospirosis Infection During Rainy Season in Thailand
- ClinicalTrials.gov ID
- NCT07865156
- Acronym / sponsor ID
- CREC087/68BR-MED30
- Conditions
- Leptospirosis, Chemoprophylaxis
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 1,000 participants (estimated)
- Lead sponsor
- Chulalongkorn UniversityUniversity, hospital or other
- Study start
- 1 Nov 2026 (estimated)
- Primary completion
- 15 Dec 2026 (estimated)
- Study completion
- 31 Jan 2027 (estimated)
- First posted
- 8 Oct 2026 (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 goal of this randomized controlled trial is to study antibiotic chemoprophylaxis to prevent leptospirosis of high-risk populations.
The main question it aims to answer is : Does the efficacy of chemoprophylaxis regimens to prevent prevent leptospirosis?
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, care provider, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Doxycycline 200 mg weekly dose | Experimental | Drug: Doxycycline |
| Placebo | Placebo comparator | Drug: Placebo |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- High-risk exposure typically refers to water or soil - particularly wet ground at workplace and/or contact with animal water reservoir
Key exclusion criteria (6 listed)
- Body temperature higher than 38 °C
- Patients were confirmed to have leptospirosis within 3 months
- Pregnancy or breastfeeding
- Allergy to doxycycline
- Cirrhosis Child-Pugh C, acute hepatitis, persistent elevated liver enzymes AST/ALT > 3 times
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 |
|---|---|---|
| DoxycyclineDoxycycline 200 mg weekly | Drug | Doxycycline 200 mg weekly dose |
| PlaceboPlacebo | Drug | Placebo |
Primary outcome
Incidence of Leptospira infection
Time frame: 1 month
Number of leptospirosis cases based on Polymerase Chain Reaction (PCR), culture and Microscopic Agglutination Test (MAT)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Oct 2026.
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Cohort of Hospitalized Patients Suspected of Leptospirosis
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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.
Sasipha Tachaboon Excellence center for critical care nephrology contact
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Doxycycline in people with Leptospirosis and Chemoprophylaxis, run by Chulalongkorn University.
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 1 inclusion and 6 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: opening soon, as of the sponsor's last update on 8 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Sasipha Tachaboon Excellence center for critical care nephrology (66635314464, sasipha.t@chulahospital.org), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Leptospira infection (time frame: 1 month). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 8 Oct 2026.