Not recruiting

Study on the Effects of Doxycycline for Preventing Antibiotic Resistance in Patients with Bacterial STDs (Chlamydia, Gonorrhea, Syphilis)

Registered drugNo placebo

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effects of a medication called doxycycline on certain bacterial infections that are sexually transmitted, such as chlamydia, gonorrhea, and syphilis. The study will use a form of doxycycline known as Doxycycline EG 200 mg Tabletten, which is taken orally as a tablet. The purpose of the study is to see if taking doxycycline after being exposed to these infections can affect how bacteria in the body respond to the medication over time.

Participants in the study will take doxycycline as a preventive measure after potential exposure to these infections. The study will monitor changes in the bacteria found in the body, particularly in the intestines, to see if they become less sensitive to doxycycline. This is important because it helps understand if the bacteria are developing resistance to the medication, which could make it less effective in the future.

The study will last for several months, with participants being observed for changes in the bacteria at different points, including at the start and after 180 days. The researchers will also look at how other bacteria, such as E. coli and K. pneumoniae, respond to doxycycline and other antibiotics like ceftriaxone and ciprofloxacin. This information will help determine the impact of using doxycycline as a preventive treatment on the overall resistance of bacteria to antibiotics.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

Step 1
Joining the trial
Upon joining the trial, you will be asked to provide written informed consent. This means you agree to participate after understanding the details of the study.
You must be at least 18 years old, have been assigned male sex at birth, and be eligible to take HIV PrEP (pre-exposure prophylaxis).
Step 2
Medication administration
You will be given a medication called doxycycline monohydrate. This is an antibiotic used to prevent bacterial infections.
The medication will be provided in the form of tablets called Doxycycline EG 200 mg Tabletten.
You will take the medication orally, which means you will swallow the tablets.
The dosage and frequency of the medication will be explained to you by the study team.
Step 3
Trial duration
The trial is expected to last until September 30, 2024.
During this time, you will be monitored to assess the impact of the medication on antimicrobial resistance, particularly in certain bacteria found in the body.
Step 4
Monitoring and assessments
Throughout the trial, you will undergo regular assessments to monitor the effects of the medication.
The main focus will be on changes in the bacteria found in your body, specifically looking at how they respond to the medication over time.
Step 5
End of trial
At the end of the trial, the study team will evaluate the data collected to understand the impact of the medication on bacterial resistance.
You will be informed about the findings and any relevant information regarding your participation.

Who can join the trial?

4 criteria

Able and willing to provide written informed consent. This means you understand the study and agree to participate.
Age 18 years old or older.
Eligible to take HIV PrEP. This is a medication that helps prevent HIV infection.
Male sex at birth.

Who cannot join the trial?

4 criteria

Patients with **bacterial sexually transmittable diseases** such as **chlamydia**, **gonorrhea**, or **syphilis** cannot participate.
Only **male** participants are allowed in the study.
Participants must be within the specified age range, which is not detailed here.
Individuals considered part of a **vulnerable population** are not eligible. This means people who might need special protection or care.

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Investigated drugs

Doxycycline is an antibiotic that is used to treat a variety of bacterial infections. In this clinical trial, it is being used as a postexposure prophylaxis, which means it is given to people after they have been exposed to a potential infection to prevent them from getting sick. The trial aims to see if using doxycycline in this way affects how well it works against certain bacteria, specifically E. coli, over time. The researchers want to find out if the bacteria become less sensitive to doxycycline after using it as a preventive measure.

Doxycycline Monohydrate

What is already known about the treatment

Doxycycline – Doxycycline is taken orally in the form of a pill and is used to prevent infections after exposure to certain bacteria. It is currently being studied in clinical trials to see if it can help prevent bacterial sexually transmitted diseases like chlamydia, gonorrhea, and syphilis. The main goal is to see if using doxycycline in this way affects how bacteria like E. coli respond to the drug over time. Doxycycline works by stopping bacteria from making proteins they need to grow, which helps to stop the infection. It is classified as a tetracycline antibiotic.

Investigated diseases

Chlamydia
Chlamydia is a common sexually transmitted infection caused by the bacterium Chlamydia trachomatis. It often presents with mild or no symptoms, making it difficult to detect without testing. When symptoms do occur, they may include genital pain and discharge. If left untreated, the infection can spread to the reproductive organs, potentially causing complications. In women, it can lead to pelvic inflammatory disease, while in men, it may cause inflammation of the epididymis. The disease can also affect the eyes and throat if transmitted through oral or ocular contact.
Gonorrhea
Gonorrhea is a sexually transmitted infection caused by the bacterium Neisseria gonorrhoeae. It primarily affects the mucous membranes of the reproductive tract, but can also infect the mouth, throat, eyes, and rectum. Symptoms in men may include a burning sensation during urination and discharge from the penis, while women may experience increased vaginal discharge or bleeding between periods. Many individuals, however, may be asymptomatic. If untreated, gonorrhea can lead to serious health issues, including infertility and increased risk of HIV transmission. The infection can also spread to the blood or joints, causing more severe complications.
Syphilis
Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. It progresses through distinct stages: primary, secondary, latent, and tertiary. The primary stage is marked by a painless sore at the infection site, while the secondary stage may involve skin rashes and mucous membrane lesions. If untreated, the disease can enter a latent phase with no symptoms, potentially progressing to the tertiary stage, which can cause severe damage to organs such as the heart and brain. Syphilis can also be transmitted from mother to child during pregnancy, leading to congenital syphilis. Early detection and treatment are crucial to prevent progression and complications.