Doxycycline Intervention for Bacterial STI ChemoprOphylaxis (DISCO)

August 1, 2024 updated by: Jonathan Troy Grennan

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.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

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 Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
560

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • Canada
    • Alberta
      • Calgary, Alberta, Canada
        • Recruiting
        • Sheldon Chumir Centre
        • Contact:
        • Principal Investigator:
          • Caley Shukalek, MD
    • British Columbia
      • Vancouver, British Columbia, Canada, V5Z4R4
        • Recruiting
        • BC Centre for Disease Control
        • Contact:
          • Ramin Azmin
          • Phone Number: 6047075617
    • Ontario
      • Hamilton, Ontario, Canada
        • Not yet recruiting
        • St. Joseph's Healthcare Hamilton
        • Contact:
          • Kelly Waters
        • Principal Investigator:
          • Kevin Woodward, MD
      • Ottawa, Ontario, Canada
        • Not yet recruiting
        • The Ottawa Hospital
        • Contact:
          • TBA
        • Principal Investigator:
          • Paul MacPherson, MD
      • Toronto, Ontario, Canada
    • Quebec

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Males, ≥ 18 years of age;
  2. 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;
  3. Intention to remain sexually active with more than one male partner in the next 12 months;
  4. At least one prior episode of a previously diagnosed and adequately treated syphilis, gonorrhea or chlamydia infection within 12 months prior to screening.

Exclusion Criteria:

  1. Known allergy to doxycycline or tetracyclines;
  2. Existing chronic or intermittent tetracycline or doxycycline use (e.g. for chronic osteomyelitis, acne).
  3. Use of medications which could lower doxycycline levels, including barbiturates, phenytoin and carbamazepine.
  4. Individuals currently using isotretinoin;
  5. Any individual capable of becoming pregnant.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: STI PrEP arm
doxycycline capsules 100mg orally daily for 12 months. Though the usual treatment dose of doxycycline is 100mg twice daily
Drug: Doxycycline Hyclate
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
Experimental: 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: Doxycycline Hyclate
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

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
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)
60 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Frequency of STIs over time
Time Frame: 60 weeks
To describe frequency of syphilis, gonorrhea, and chlamydia incident infections among participants over the study period
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
To determine the tolerability and safety of doxycycline chemoprophylaxis
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
To determine the acceptability of doxycycline chemoprophylaxis
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
To evaluate the change in sexual behaviour reported by participants over the study period
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
To evaluate antimicrobial resistance in bacterial STIs and common commensal pathogens over study period
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
To evaluate antimicrobial resistance in bacterial STIs and common commensal pathogens over study period
Over 48 weeks
Proportion of individuals with adverse event-related study drug discontinuation in each study arm
Time Frame: Over 60 weeks
To determine the tolerability and safety of doxycycline chemoprophylaxis
Over 60 weeks
Rate of adherence to study treatment (STI PrEP vs. PEP) by participants.
Time Frame: Over 48 weeks
To assess for superiority of doxycycline PrEP over PEP (if non-inferiority is shown)
Over 48 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Jonathan Troy Grennan

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Canadian Institutes of Health Research (CIHR)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Troy Grennan, MD, University of British Columbia

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 2, 2023

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 31, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
June 30, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
February 12, 2021

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 16, 2021

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
February 21, 2021

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 5, 2024

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 1, 2024

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2024

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • BritishCCDC3

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

IPD Plan Description

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.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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