Bacterial Sexually Transmitted DiseasesNCT04762134
Doxycycline Intervention for Bacterial STI ChemoprOphylaxis (DISCO)
A study testing Doxycycline Hyclate in people with Bacterial Sexually Transmitted Diseases, run by Jonathan Troy Grennan at 6 sites in Canada.
Trial summary
There is a growing epidemic of the bacterial sexually transmitted infections (STIs) syphilis, chlamydia and gonorrhea worldwide; similarly concerning trends have been noted in Canada, where increases of over 160% have been seen in bacterial STIs over the last decade. Read more about this study
- Who is it for?
- Ages 18 years and older, men only
- Conditions the study is for
- Bacterial Sexually Transmitted Diseases
- What is being tested?
- Doxycycline Hyclate
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 560 participants
- Where
- 6 sitesCanada
- Study dates
- 2 Jun 2023to 30 Jun 2027
- Phase
- Interventional
- 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
- Men only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Males, ≥ 18 years of age;
- Any sexual activity (i.e. oral sex, insertive or receptive anal sex, with or without a condom) with more than one male partner in the preceding 12 months;
- Intention to remain sexually active with more than one male partner in the next 12 months;
- At least one prior episode of a previously diagnosed and adequately treated syphilis, gonorrhea or chlamydia infection within 12 months prior to screening.
Who cannot join
- Known allergy to doxycycline or tetracyclines;
- Existing chronic or intermittent tetracycline or doxycycline use (e.g. for chronic osteomyelitis, acne).
- Use of medications which could lower doxycycline levels, including barbiturates, phenytoin and carbamazepine.
- Individuals currently using isotretinoin;
- Any individual capable of becoming pregnant.
Trial locations and contacts
6 sites in 1 country. Contact the study team or a site near you to ask about taking part.
6 sites in 1 country
Canada6 sites, 6 recruiting
- Recruiting
Sheldon Chumir Centre
Calgary, Alberta
Grace Kwon, disco@ucalgary.ca
Caley Shukalek, MD
- Not yet recruiting
St. Joseph's Healthcare Hamilton
Hamilton, Ontario
Kelly Waters
Kevin Woodward, MD
- Recruiting
McGill University Health Centre
Montreal, Quebec
Nathalie Paisible, nathalie.paisible@muhc.mcgill.ca
Turna Hortoglu, turna.hortoglu@muhc.mcgill.ca
- Not yet recruiting
The Ottawa Hospital
Ottawa, Ontario
TBA
Paul MacPherson, MD
- Recruiting
St. Michael's Hospital
Toronto, Ontario
Reva Persaud, optionslab@unityhealth.to
Stanley Onyegbule, optionslab@unityhealth.to
- Recruiting
BC Centre for Disease Control
Vancouver, British Columbia, V5Z4R4
Ramin Azmin, 6047075617
About this study
Official title: A Randomized Trial of Doxycycline Chemoprophylaxis for the Prevention of Sexually Transmitted Infections in Gay, Bisexual and Other Men Who Have Sex With Men (gbMSM)
There is a growing epidemic of the bacterial sexually transmitted infections (STIs) syphilis, chlamydia and gonorrhea worldwide; similarly concerning trends have been noted in Canada, where increases of over 160% have been seen in bacterial STIs over the last decade. In Canada, gay, bisexual, and other men who have sex with men (gbMSM) - including those living with HIV - are disproportionately impacted by bacterial STIs5,6These dramatic increases in bacterial STIs, the potential development of serious complications including AMR, and waning effectiveness of the promotion of conventional STI prevention tools (e.g. condoms), signals the need for novel STI prevention strategies and tools to mitigate STI-related complications. A rigorous randomized controlled trial will be conducted to compare STI PrEP vs. STI PEP and definitively assess the efficacy, safety, antimicrobial resistance profiles and costs associated with doxycycline-based STI prevention.
Read the detailed description
With the rising rates of STIs among gbMSM populations in Canada, there is an urgent need for novel interventions to prevent significant sequelae (e.g. neurosyphilis) and onward transmission of untreated infections. Despite longstanding public health efforts to encourage conventional strategies of STI prevention, gbMSM continue to bear the burden of syphilis which poses synergistic effects in the transmission of HIV. This study will add to this field through providing the first methodologically rigorous, prospective multicentre, open-label randomized controlled trial (RCT) of doxycycline-based STI PrEP (daily 100mg doxycycline) versus STI PEP (200mg doxycycline after exposure event) for the prevention of bacterial STIs among gbMSM over 15 months (60 weeks) of follow-up with adequate power to address drug efficacy in the prevention of bacterial STIs. Beyond the determination of efficacy, our trial will provide insight to the unique challenges of medication adherence through assessing the acceptability, tolerability and safety of therapy with doxycycline. This study aims to provide health care providers one additional tool to address the burden of STIs in populations with an increased likelihood of infection.
- Conditions
- Bacterial Sexually Transmitted Diseases
- Being tested
- Doxycycline Hyclate
- Keywords
- Sexually transmitted infections (STIs), Doxycycline, Pre-exposure prophylaxis (PrEP), Post-exposure prophylaxis (PEP), Gay, bisexual, men who have sex with other men (gbMSM)
- Medical subject headings
- Sexually Transmitted Diseases, Bacterial, Sexually Transmitted Diseases, Homosexuality, Bisexuality
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Doxycycline HyclateDrug
STI PrEP arm: doxycycline capsules 100mg orally daily for 12 months STI PEP arm: doxycycline 200mg orally once within 24-72 hours following each sexual encounter deemed at risk (i.e. condomless anal or oral sex), to a maximum of six pills (i.e. 600 mg total) per week
| Study group | Role | What they receive |
|---|---|---|
| STI PrEP arm | Experimental | doxycycline capsules 100mg orally daily for 12 months. Though the usual treatment dose of doxycycline is 100mg twice daily Receives: Drug: Doxycycline Hyclate |
| STI PEP arm | Experimental | doxycycline 200mg orally once within 24-72 hours following each sexual encounter deemed at risk (i.e. condomless anal or oral sex), to a maximum of six pills (i.e. 600 mg total) per week Receives: Drug: Doxycycline Hyclate |
What is being measured
The primary outcome is the main question the study is designed to answer.
Plasma doxycycyline levels to determine efficacy of doxycycline chemoprophylaxis
To determine the efficacy of doxycycline chemoprophylaxis in preventing incident bacterial STI cases (syphilis, gonorrhea, and/or chlamydia, including LGV)
Measured: 60 weeks
Secondary outcomes (8)
Frequency of STIs over time
To describe frequency of syphilis, gonorrhea, and chlamydia incident infections among participants over the study period
Measured: 60 weeks
Proportion of individuals reporting grade 3 or 4 adverse events in each study arm as assessed by the Division of AIDS Table for Grading the Severity of Adult and Pediatric Adverse Events
To determine the tolerability and safety of doxycycline chemoprophylaxis
Measured: 60 weeks
Proportion of participants who report acceptability, community norms and partner attitudes of STI PrEP and PEP based on responses from questionnaires
To determine the acceptability of doxycycline chemoprophylaxis
Measured: 60 weeks
Change in self-reported sexual activity defined as increases in condomless sexual acts and number of sexual partners based on responses from questionnaires
To evaluate the change in sexual behaviour reported by participants over the study period
Measured: 60 weeks
Proportion of individuals with evidence of tetracycline class resistance in common flora (Staphylococcus aureus, Streptococcus pyogenes and Streptococcus pneumoniae) at 24 and 48 weeks.
To evaluate antimicrobial resistance in bacterial STIs and common commensal pathogens over study period
Measured: Over 48 weeks
Proportion of cases with resistance to penicillins, tetracyclines or macrolides in syphilis, and tetracycline resistance in gonorrhea and chlamydia isolates taken from the anus, oral cavity or urethra.
To evaluate antimicrobial resistance in bacterial STIs and common commensal pathogens over study period
Measured: Over 48 weeks
Proportion of individuals with adverse event-related study drug discontinuation in each study arm
To determine the tolerability and safety of doxycycline chemoprophylaxis
Measured: Over 60 weeks
Rate of adherence to study treatment (STI PrEP vs. PEP) by participants.
To assess for superiority of doxycycline PrEP over PEP (if non-inferiority is shown)
Measured: Over 48 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Feb 2021
- Study start2 Jun 2023
- Primary completion31 Dec 2026 (estimated)
- Study completion30 Jun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Bacterial Sexually Transmitted DiseasesStudies of the same condition, open and under way.
- 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
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomization with a 1:1 ratio
- Masking
- None (open label)
- Enrolment
- 560 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Jonathan Troy Grennan
- Sponsor type
- Other government
- Collaborators
- Canadian Institutes of Health Research (CIHR)
- Responsible party
- Sponsor-investigator, Jonathan Troy Grennan, British Columbia Centre for Disease Control
- Investigators
- Troy Grennan, MD, Principal investigator, University of British Columbia
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04762134
- Sponsor's protocol ID
- BritishCCDC3
- Status last verified
- Aug 2024
- First submitted
- 12 Feb 2021
- Last updated
- 5 Aug 2024
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Our results will be targeted to four main groups of stakeholders: clinicians, public health, researchers, and community.The Community-Based Research Centre for Gay Men's Health, the Canadian AIDS Treatment Information Exchange (CATIE), and the AIDS Committee of Toronto will help facilitate KTE locally and nationally. We will disseminate our findings to a large, international audience of clinicians and public-health professionals by publishing in high-impact peer-reviewed journals.
Study at a glance
From the registry record, last updated by the sponsor on 5 Aug 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Randomized Trial of Doxycycline Chemoprophylaxis for the Prevention of Sexually Transmitted Infections in Gay, Bisexual and Other Men Who Have Sex With Men (gbMSM)
- ClinicalTrials.gov ID
- NCT04762134
- Acronym / sponsor ID
- BritishCCDC3
- Conditions
- Bacterial Sexually Transmitted Diseases
- Keywords
- Sexually transmitted infections (STIs), Doxycycline, Pre-exposure prophylaxis (PrEP), Post-exposure prophylaxis (PEP), Gay, bisexual, men who have sex with other men (gbMSM)
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 560 participants (estimated)
- Lead sponsor
- Jonathan Troy GrennanOther government
- Collaborators
- Canadian Institutes of Health Research (CIHR)
- Study start
- 2 Jun 2023 (actual)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 30 Jun 2027 (estimated)
- First posted
- 21 Feb 2021 (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.
There is a growing epidemic of the bacterial sexually transmitted infections (STIs) syphilis, chlamydia and gonorrhea worldwide; similarly concerning trends have been noted in Canada, where increases of over 160% have been seen in bacterial STIs over the last decade. In Canada, gay, bisexual, and other men who have sex with men (gbMSM) - including those living with HIV - are disproportionately impacted by bacterial STIs5,6These dramatic increases in bacterial STIs, the potential development of serious complications including AMR, and waning effectiveness of the promotion of conventional STI prevention tools (e.g. condoms), signals the need for novel STI prevention strategies and tools to mitigate STI-related complications. A rigorous randomized controlled trial will be conducted to compare STI PrEP vs. STI PEP and definitively assess the efficacy, safety, antimicrobial resistance profiles and costs associated with doxycycline-based STI prevention.
Detailed description
With the rising rates of STIs among gbMSM populations in Canada, there is an urgent need for novel interventions to prevent significant sequelae (e.g. neurosyphilis) and onward transmission of untreated infections. Despite longstanding public health efforts to encourage conventional strategies of STI prevention, gbMSM continue to bear the burden of syphilis which poses synergistic effects in the transmission of HIV. This study will add to this field through providing the first methodologically rigorous, prospective multicentre, open-label randomized controlled trial (RCT) of doxycycline-based STI PrEP (daily 100mg doxycycline) versus STI PEP (200mg doxycycline after exposure event) for the prevention of bacterial STIs among gbMSM over 15 months (60 weeks) of follow-up with adequate power to address drug efficacy in the prevention of bacterial STIs. Beyond the determination of efficacy, our trial will provide insight to the unique challenges of medication adherence through assessing the acceptability, tolerability and safety of therapy with doxycycline. This study aims to provide health care providers one additional tool to address the burden of STIs in populations with an increased likelihood of infection.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Randomization with a 1:1 ratio
| Arm | Type | Receives |
|---|---|---|
| STI PrEP arm | Experimental | Drug: Doxycycline Hyclatedoxycycline capsules 100mg orally daily for 12 months. Though the usual treatment dose of doxycycline is 100mg twice daily |
| STI PEP arm | Experimental | Drug: Doxycycline Hyclatedoxycycline 200mg orally once within 24-72 hours following each sexual encounter deemed at risk (i.e. condomless anal or oral sex), to a maximum of six pills (i.e. 600 mg total) per week |
Who may qualify
- Ages
- 18 years and older
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Males, ≥ 18 years of age;
- Any sexual activity (i.e. oral sex, insertive or receptive anal sex, with or without a condom) with more than one male partner in the preceding 12 months;
- Intention to remain sexually active with more than one male partner in the next 12 months;
- At least one prior episode of a previously diagnosed and adequately treated syphilis, gonorrhea or chlamydia infection within 12 months prior to screening.
Key exclusion criteria (5 listed)
- Known allergy to doxycycline or tetracyclines;
- Existing chronic or intermittent tetracycline or doxycycline use (e.g. for chronic osteomyelitis, acne).
- Use of medications which could lower doxycycline levels, including barbiturates, phenytoin and carbamazepine.
- Individuals currently using isotretinoin;
- Any individual capable of becoming pregnant.
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 |
|---|---|---|
| Doxycycline HyclateSTI PrEP arm: doxycycline capsules 100mg orally daily for 12 months STI PEP arm: doxycycline 200mg orally once within 24-72 hours following each sexual encounter deemed at risk (i.e. condomless anal or oral sex), to a maximum of six pills (i.e. 600 mg total) per week | Drug | STI PEP arm, STI PrEP arm |
Primary outcome
Plasma doxycycyline levels to determine efficacy of doxycycline chemoprophylaxis
Time frame: 60 weeks
To determine the efficacy of doxycycline chemoprophylaxis in preventing incident bacterial STI cases (syphilis, gonorrhea, and/or chlamydia, including LGV)
8 secondary outcomes
Frequency of STIs over time
Time frame: 60 weeks
Proportion of individuals reporting grade 3 or 4 adverse events in each study arm as assessed by the Division of AIDS Table for Grading the Severity of Adult and Pediatric Adverse Events
Time frame: 60 weeks
Proportion of participants who report acceptability, community norms and partner attitudes of STI PrEP and PEP based on responses from questionnaires
Time frame: 60 weeks
Change in self-reported sexual activity defined as increases in condomless sexual acts and number of sexual partners based on responses from questionnaires
Time frame: 60 weeks
Proportion of individuals with evidence of tetracycline class resistance in common flora (Staphylococcus aureus, Streptococcus pyogenes and Streptococcus pneumoniae) at 24 and 48 weeks.
Time frame: Over 48 weeks
Proportion of cases with resistance to penicillins, tetracyclines or macrolides in syphilis, and tetracycline resistance in gonorrhea and chlamydia isolates taken from the anus, oral cavity or urethra.
Time frame: Over 48 weeks
Proportion of individuals with adverse event-related study drug discontinuation in each study arm
Time frame: Over 60 weeks
Rate of adherence to study treatment (STI PrEP vs. PEP) by participants.
Time frame: Over 48 weeks
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 5 Aug 2024.
- Individual participant dataSharing planned: Undecided. Our results will be targeted to four main groups of stakeholders: clinicians, public health, researchers, and community.The Community-Based Research Centre for Gay Men's Health, the Canadian AIDS Treatment Information Exchange (CATIE), and the AIDS Committee of Toronto will help facilitate KTE locally and nationally. We will disseminate our findings to a large, international audience of clinicians and public-health professionals by publishing in high-impact peer-reviewed journals.
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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.
Troy Grennan, MD principal investigator
University of British Columbia
6 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Doxycycline Hyclate in people with Bacterial Sexually Transmitted Diseases, run by Jonathan Troy Grennan at 6 sites in Canada.
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 4 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: looking for participants now, as of the sponsor's last update on 5 Aug 2024. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in Canada. 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?
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 Saira Mohammed (6047542171, smohammed@bccfe.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Plasma doxycycyline levels to determine efficacy of doxycycline chemoprophylaxis (time frame: 60 weeks). 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 5 Aug 2024; AzTrials last refreshed its copy on 6 Nov 2026.