Doxycycline for STDs Prevention

(foXXxy doxy Trial)

Not yet recruiting at 14 trial locations

Overseen By Nancy Liu

Age: < 65

Sex: Female

Trial Phase: Phase 4

Sponsor: Westat

Must not be taking: Barbiturates, Phenytoin, Lithium, others

Disqualifiers: Male, Pregnant, Tetracycline allergy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 5 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 52 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests whether doxycycline, an antibiotic, can prevent bacterial sexually transmitted infections (STIs) such as gonorrhea, chlamydia, or early syphilis in young women. Participants will either take doxycycline after unprotected sex, take it weekly, or follow standard STI testing and health counseling. The trial aims to evaluate the effectiveness, acceptability, and impact on antibiotic resistance of these methods to guide public health decisions. Young women who have had unprotected sex and a recent STI diagnosis may be suitable for this study. As a Phase 4 trial, this research focuses on understanding how the already FDA-approved doxycycline can benefit more patients, offering participants a chance to contribute to important public health insights.

Will I have to stop taking my current medications?

If you are taking medications that interact with doxycycline, like barbiturates, phenytoin, lithium, carbamazepine, systemic retinoids, or warfarin, you may need to stop them to participate in the trial. The trial does not specify other medications, so it's best to discuss your current medications with the study team.

What is the safety track record for doxycycline?

Previous studies have shown that doxycycline is safe for use. Research indicates that taking 200 mg of doxycycline after sex can significantly reduce the risk of certain bacterial STIs, such as syphilis and chlamydia, by more than 70%. This suggests the treatment is generally well-tolerated with few issues.

The studies report no serious side effects, indicating most people can take the medication without problems. Some might experience mild side effects like an upset stomach or increased sensitivity to the sun, which can lead to easier sunburn. These side effects are usually not severe and tend to resolve on their own.

Overall, doxycycline has been used safely for a long time, even for other conditions, making it a reliable option for preventing STIs. ^{1 2 3 4 5}

Why are researchers enthusiastic about this study treatment?

Researchers are excited about these treatments for STD prevention because they offer innovative approaches compared to traditional methods like condoms and regular STI testing. The on-demand doxyPEP involves taking doxycycline within 72 hours after unprotected sex, potentially offering a proactive way to prevent infections right after exposure. Meanwhile, the weekly doxycycline option provides consistent protection, regardless of sexual activity, adding a preventative layer similar to how some medications are used for other health conditions like malaria prophylaxis. These approaches could revolutionize STD prevention by providing more flexible and user-friendly options.

What evidence suggests that doxycycline might be an effective treatment for preventing STIs?

Research has shown that doxycycline can effectively prevent bacterial sexually transmitted infections (STIs). In this trial, participants in one arm will take doxycycline within 72 hours after unprotected sex. Studies have found that this approach greatly lowers the risk of contracting STIs like syphilis and chlamydia. For instance, one study discovered that the number of these infections dropped by two-thirds compared to usual care. Another arm of this trial involves taking doxycycline once a week, which has also shown promise in reducing STI rates. These findings suggest that doxycycline could be a strong option for preventing certain STIs when used correctly. ^{6 7 8 9 10}

Who Is on the Research Team?

Jenell Stewart, DO, MPH

Principal Investigator

Hennepin Healthcare

Cherie Blaire, MD, PhD

Principal Investigator

University of California, Los Angeles

Are You a Good Fit for This Trial?

This trial is for individuals assigned female at birth who are seeking to prevent bacterial sexually transmitted infections (STIs). Participants must be willing to take doxycycline weekly and be monitored for the development of antimicrobial resistance.

Inclusion Criteria

Willing to provide written informed consent to participate in the study

Willing to undergo all required study procedures

I am between 13 and 29 years old.

Exclusion Criteria

Co-enrollment in any other concurrent interventional research or studies that may interfere with this study, such as an STI prevention trial, unless approved by Protocol Team in writing

Lack of consistent access (or anticipated weekly access for 52 weeks of survey completion) to smartphone that can access the HMP app

Presence of any other medical condition, medical/behavioral intervention, or other conditions that, in the opinion of the clinical site Project Lead (PL)/Investigator of Record (IoR) or designee, could interfere with adherence to study procedures or compromise interpretation of study results

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants are randomized to receive on-demand doxycycline post-exposure prophylaxis, weekly doxycycline, or standard of care, with quarterly STI testing and sexual health counseling

52 weeks

Quarterly visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment, including STI testing and resistance testing

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Doxycycline

Trial Overview

The study tests if taking a delayed-release form of doxycycline hyclate, an antibiotic, can reduce the risk of STIs like gonorrhea, chlamydia, and syphilis. It's an open-label trial where participants know what treatment they're getting.

How Is the Trial Designed?

Group I: Weekly doxycycline Experimental Treatment 1 Intervention

Participants will take by mouth doxycycline 200 mg weekly regardless of sexual activity in addition to standard of care STI testing/treatment and sexual health counseling.

Group II: Quarterly STI testing/treatment and sexual health counseling Experimental Treatment 1 Intervention

Participants will be followed per standard of care with quarterly STI testing/treatment and sexual health counseling.

Group III: On-demand doxyPEP Experimental Treatment 1 Intervention

Participants will take by mouth doxycycline 200 mg as soon as possible and within 72 hours after any condomless oral, vaginal, and/or anal sex in addition to standard of care STI testing/treatment and sexual health counseling.

Doxycycline is already approved in United States, European Union, Canada, Japan for the following indications:

Approved in United States as Doxycycline for:

• Acne
• Bacterial infections
• Chlamydia
• Gonorrhea
• Lyme disease
• Malaria
• Pneumonia
• Rosacea
• Urinary tract infections

Approved in European Union as Doxycycline for:

• Acne
• Bacterial infections
• Chlamydia
• Gonorrhea
• Lyme disease
• Malaria
• Pneumonia
• Rosacea
• Urinary tract infections

Approved in Canada as Doxycycline for:

• Acne
• Bacterial infections
• Chlamydia
• Gonorrhea
• Lyme disease
• Malaria
• Pneumonia
• Rosacea
• Urinary tract infections

Approved in Japan as Doxycycline for:

• Acne
• Bacterial infections
• Chlamydia
• Gonorrhea
• Lyme disease
• Malaria
• Pneumonia
• Rosacea
• Urinary tract infections

Who Is Running the Clinical Trial?

Westat

Lead Sponsor

Trials

49

Recruited

39,700+

National Institute of Allergy and Infectious Diseases (NIAID)/Division of AIDS (DAIDS)

Collaborator

Trials

1

Recruited

760+

National Institute on Drug Abuse (NIDA)

Collaborator

Trials

2,658

Recruited

3,409,000+

National Institute of Mental Health (NIMH)

Collaborator

Trials

3,007

Recruited

2,852,000+

Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Collaborator

Trials

2,103

Recruited

2,760,000+

National Institutes of Health (NIH)

Collaborator

Trials

2,896

Recruited

8,053,000+

Florida State University

Collaborator

Trials

234

Recruited

41,100+

National Institute of Allergy and Infectious Diseases (NIAID)

Collaborator

Trials

3,361

Recruited

5,516,000+

The Office of the Director, National Institutes of Health (NIH)

Collaborator

Citations

1.

cdc.gov

cdc.gov/sti/hcp/doxy-pep/index.html

Doxy PEP for Bacterial STI Prevention

Doxy PEP has proven to reduce the risk of getting some bacterial STIs for gay, bisexual, and other men who have sex with men and transgender women at increased ...

2.

ncbi.nlm.nih.gov

ncbi.nlm.nih.gov/books/NBK597440/

Doxycycline Post-Exposure Prophylaxis to Prevent Bacterial ...

Doxy-PEP was associated with significant reductions in the incidence of first STI and, in individual analyses, of incident chlamydia and ...

3.

ucsf.edu

ucsf.edu/news/2023/02/424861/doxycycline-sti-prevention-highly-effective-minimal-drug-resistance

Doxycycline for STI Prevention: Highly Effective, Minimal ...

It involves taking one 200mg pill of doxycycline, a kind of tetracycline, as soon as possible but no later than three days after having sex ...

4.

cedars-sinai.org

cedars-sinai.org/newsroom/what-you-need-to-know-taking-doxycycline-for-safer-sex/

What You Need to Know: Taking Doxycycline for Safer Sex

But new trial results showed doxycycline could be an effective new tool to limit the spread of syphilis and chlamydia if taken as a single 200- ...

5.

clinicaltrials.gov

clinicaltrials.gov/study/NCT06738407?term=nichd%20Sexually%20Transmitted%20Diseases&viewType=Table&rank=1

NCT06738407 | Doxycycline Prophylaxis for Prevention of ...

Participants will take by mouth doxycycline 200 mg weekly regardless of sexual activity in addition to standard of care STI testing/treatment and sexual health ...

6.

cdc.gov

cdc.gov/mmwr/volumes/73/rr/rr7302a1.htm

CDC Clinical Guidelines on the Use of Doxycycline .. ...

200 mg of doxycycline taken within 72 hours after sex has been shown to reduce syphilis and chlamydia infections by >70% and gonococcal infections by ...

7.

pubmed.ncbi.nlm.nih.gov

pubmed.ncbi.nlm.nih.gov/40396488/

Doxycycline post-exposure prophylaxis as prevention of STIs

Doxycycline post-exposure prophylaxis ('doxyPEP') is an emerging strategy to prevent bacterial sexually transmitted infections (STIs).

8.

nejm.org

nejm.org/doi/full/10.1056/NEJMoa2211934

Postexposure Doxycycline to Prevent Bacterial Sexually ...

The combined incidence of gonorrhea, chlamydia, and syphilis was lower by two thirds with doxycycline postexposure prophylaxis than with standard care.

9.

sciencedirect.com

sciencedirect.com/science/article/pii/S1201971224002571

Doxycycline prophylaxis for the prevention of sexually ...

Doxycycline prophylaxis is an effective tool for bacterial STI prevention. 200 mg doxycycline after sex significantly reduced the risk of chlamydia and ...

10.

thelancet.com

thelancet.com/journals/laninf/article/PIIS1473-3099(25)00085-4/abstract

Doxycycline to prevent bacterial sexually transmitted ...

Doxy-PEP was effective in reducing bacterial STIs in this population of men who have sex with men and transgender women, including during an ...