Doxy-Post-exposure Prophylaxis

NCT05853120 | Completed Phase 4 Results DMC FDA Drug

• 2 other identifiers: STUDY0000555275D30122C14484
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this project is to collect data regarding the ability of various oral doses of doxycycline to penetrate mucosal tissues in men and women to inform the combination of doxycycline with antiretrovirals (ARVs) for the development of single-dose event-driven multipurpose prevention strategies to protect against HIV and sexually transmitted infections (STIs). This study is of importance in the field of research because it allows the exploration of new dosing strategies that would permit a single event-driven oral dose of medications that could provide protection from HIV as well as other STIs. The study population that this study seeks to enroll are healthy people assigned male or female sex at birth and not using gender-affirming hormone therapy and are willing to undergo study procedures. Recruitment: Both face-to-face and online engagements will be conducted to recruit study participants. Face-to-face locations include bars and nightclubs, community organizations serving study populations, sports events, and community venues, and online engagements include dating sites, social networks, and craigslist, amongst other social medial platforms.

Conditions

Sexually Transmitted Diseases

Keywords

Prevention; STI; Post-exposure prophylaxis; HIV; PEP

Outcome Measures

Primary Outcomes (4)

• Doxycycline Concentrations in Rectal Tissues

  Rectal biopsies were collected 24 hours after administration of the initial dose of doxycycline

  Day 2

• Doxycycline Concentrations in Vaginal Tissues

  Vaginal biopsies collected 24 hours after administration of the initial dose of doxycycline

  Day 2

• Doxycycline Concentrations in Rectal Tissues After the Fifth Dose of Doxycycline

  Self-collected swabs and rectal biopsies were collected 24 hours after administration of the fifth dose of doxycycline

  Day 15

• Doxycycline Concentrations in Vaginal Tissues Collected 24 Hours After the Fifth Dose of Doxycycline

  Self-collected swabs and vaginal biopsies were collected 24 hours after administration of the fifth dose of doxycycline

  Day 15

Other Outcomes (6)

• Changes in Blood Doxycycline Concentrations in Participants Taking 5 Doses of Doxycycline.

  Throughout study up to 3 months after fifth dose

• Changes in Urine Doxycycline Concentrations in Participants Taking 5 Doses of Doxycycline.

  Throughout study up to 3 months after fifth dose

• Changes in Doxycycline Concentrations in Throat Secretions in Participants Taking 5 Doses of Doxycycline.

  Throughout study up to 3 months after fifth dose

Study Arms (2)

Doxycycline 100 mg

ACTIVE COMPARATOR

Doxycycline 100mg Participants will receive the first assigned dose of Doxycycline at the clinic on days 0 and 3 at the clinic. The other three doses of the medication will be taken at home on days 7 and 10.

Drug: Doxycycline

Doxycycline 200 mg

ACTIVE COMPARATOR

Doxycycline - 200 mg Participants will receive the first assigned dose of Doxycycline at the clinic on days 0 and 3 at the clinic. The other three doses of the medication will be taken at home on days 7 and 10

Drug: Doxycycline

Interventions

Doxycycline DRUG

Doxycycline is used to treat or prevent infections that are strongly suspected to be caused by bacteria; it is an antimicrobial drug indicated for bacterial infections such as sexually transmitted infections. Doxycycline (DOX) will be given orally at 100 and 200 mg doses.

Also known as: DOX

Doxycycline 100 mg; Doxycycline 200 mg

Eligibility Criteria

• Age: 18 Years - 59 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged 18-59 years
• Assigned male sex or female sex at birth
• In good general health
• Not currently taking doxycycline or other tetracycline-derived antibiotics and no plans to initiate during the study
• For HIV-positive people, on stable antiretroviral therapy with an undetectable viral load and CD4 count\> 300ul/ml
• Willing to use condoms consistently for the duration of the study
• Able to provide informed consent
• No plans for relocation in the next 4 months
• Not pregnant and does not plan on getting pregnant for the duration of the study
• Willing to undergo peripheral blood, urine, rectal or vaginal secretion collection, and a rectal or vaginal and cervical biopsy procedure
• Willing to use study products as directed

You may not qualify if:

• Current or chronic history of liver disease
• Continued need for, or use during the 90 days before enrollment, of the following medications:
• Systemic immunomodulatory agents
• Supraphysiologic doses of steroids (short course steroids less than 7 days duration, allowable at the discretion of the investigators)
• Chemotherapy or radiation for treatment of malignancy
• Experimental medications, vaccines, or biologicals
• Intent to use doxycycline or other tetracycline-derived antibiotics during the study, outside of the study procedures
• Any other clinical condition or prior therapy that, in the opinion of the investigator, would make the patient unsuitable for the study or unable to comply with the study requirements
• Known allergic reaction to study drugs.
• Significant laboratory abnormalities at baseline visit for rectal biopsies, including but not limited to:
• Hgb ≤ 10 g/dL
• PTT \> 1.5x ULN or INR \> 1.5x ULN
• Platelet count \<100,000

Sponsors & Collaborators

• Emory University: lead
• Centers for Disease Control and Prevention: collaborator

Study Sites (1)

Hope Clinic

Atlanta, Georgia, 30322, United States

Location

MeSH Terms

Conditions

Sexually Transmitted Diseases

Interventions

Doxycycline

Condition Hierarchy (Ancestors)

Communicable Diseases; Infections; Genital Diseases; Urogenital Diseases; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Tetracyclines; Naphthacenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Polycyclic Compounds

Results Point of Contact

• Title: Colleen Kelley
• Organization: Emory University

scolleen.kelley@emory.edu

404-712-1823

Study Officials

• Colleen Kelley, MD, MPH

  Emory University

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: May 2, 2023
• First Posted: May 10, 2023
• Study Start: May 31, 2023
• Primary Completion: September 25, 2024
• Study Completion: December 24, 2024
• Last Updated: September 11, 2025
• Results First Posted: September 11, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP
• Time Frame: The research team will share de-identified participant data after the primary manuscript publication.
• Access Criteria: Interested investigators can request deidentified data by email for secondary data analyses and/or meta-analyses.

Locations

US (1)