Doxycycline for Sexually Transmitted Infections
Recruiting in Palo Alto (17 mi)
+5 other locations
Overseen byTroy Grennan, MD
Age: 18+
Sex: Male
Travel: May Be Covered
Time Reimbursement: Varies
Trial Phase: Academic
Recruiting
Sponsor: Jonathan Troy Grennan
Must not be taking: Barbiturates, Phenytoin, Carbamazepine, Isotretinoin
Disqualifiers: Allergy to doxycycline, Pregnancy, others
No Placebo Group
Approved in 4 Jurisdictions
Trial Summary
What is the purpose of this trial?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.
Will I have to stop taking my current medications?
The trial requires that you stop using certain medications that could lower doxycycline levels, such as barbiturates, phenytoin, and carbamazepine. If you are using isotretinoin, you will also need to stop taking it to participate.
What evidence supports the effectiveness of the drug doxycycline for treating sexually transmitted infections?
Research shows that doxycycline is effective in treating infections like Chlamydia trachomatis, with a high cure rate of 100% in one study. It is also considered a good option for managing various bacterial sexually transmitted infections due to its efficacy and ease of use.
12345Is doxycycline generally safe for humans?
Doxycycline is generally considered safe for humans, but it can have side effects like gastrointestinal issues, tooth development concerns in children, and photosensitivity (increased sensitivity to sunlight). Rarely, it can cause more serious effects like acute pancreatitis (inflammation of the pancreas).
26789How is the drug Doxycycline Hyclate unique for treating sexually transmitted infections?
Doxycycline Hyclate is unique because it is a broad-spectrum antibiotic that can be taken orally once or twice a day, making it convenient for patients. It is effective against a wide range of bacteria, including those causing sexually transmitted infections, and has been shown to be safe with minimal side effects. Additionally, it is being explored for use as a preventive measure against STIs, although there are concerns about potential antimicrobial resistance.
125910Eligibility Criteria
The DISCO trial is for gay, bisexual, and other men who have sex with men (gbMSM) over 18 years old. Participants must have had multiple male partners and at least one bacterial STI in the past year. They should not be on certain drugs that affect doxycycline levels, allergic to tetracyclines, using doxycycline regularly or taking isotretinoin.Inclusion Criteria
I plan to be sexually active with multiple male partners this year.
I had syphilis, gonorrhea, or chlamydia treated in the last year.
I have had sexual activity with more than one male partner in the last year.
+1 more
Exclusion Criteria
You are allergic to doxycycline or tetracyclines.
I am capable of becoming pregnant.
I am currently taking isotretinoin.
+2 more
Trial Timeline
Screening
Participants are screened for eligibility to participate in the trial
2-4 weeks
Treatment
Participants receive doxycycline-based STI PrEP or PEP for the prevention of bacterial STIs
12 months
Regular visits for monitoring and assessment
Follow-up
Participants are monitored for safety, effectiveness, and antimicrobial resistance after treatment
60 weeks
Open-label extension (optional)
Participants may opt into continuation of treatment long-term
Long-term
Participant Groups
This study tests whether Doxycycline Hyclate can prevent bacterial STIs like syphilis, chlamydia, and gonorrhea in gbMSM. It's a randomized controlled trial comparing two prevention strategies: pre-exposure prophylaxis (PrEP) versus post-exposure prophylaxis (PEP).
2Treatment groups
Experimental Treatment
Group I: STI PrEP armExperimental Treatment1 Intervention
doxycycline capsules 100mg orally daily for 12 months. Though the usual treatment dose of doxycycline is 100mg twice daily
Group II: STI PEP armExperimental Treatment1 Intervention
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
Doxycycline Hyclate is already approved in United States, European Union, Canada, Australia for the following indications:
🇺🇸 Approved in United States as Doxycycline Hyclate for:
- Acne
- Malaria
- Skin infections
- Sexually transmitted infections
- Lyme disease
🇪🇺 Approved in European Union as Doxycycline Hyclate for:
- Acne
- Malaria
- Skin infections
- Sexually transmitted infections
- Lyme disease
🇨🇦 Approved in Canada as Doxycycline Hyclate for:
- Acne
- Malaria
- Skin infections
- Sexually transmitted infections
- Lyme disease
🇦🇺 Approved in Australia as Doxycycline Hyclate for:
- Acne
- Malaria
- Skin infections
- Sexually transmitted infections
- Lyme disease
Find a Clinic Near You
Research Locations NearbySelect from list below to view details:
The Ottawa HospitalOttawa, Canada
Sheldon Chumir CentreCalgary, Canada
St. Joseph's Healthcare HamiltonHamilton, Canada
St. Michael's HospitalToronto, Canada
More Trial Locations
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Who Is Running the Clinical Trial?
Jonathan Troy GrennanLead Sponsor
Canadian Institutes of Health Research (CIHR)Collaborator
References
A systematic review of the impacts of oral tetracycline class antibiotics on antimicrobial resistance in normal human flora. [2022]There is interest in doxycycline as prophylaxis against sexually transmitted infections (STIs), but concern about antimicrobial resistance (AMR). We conducted a systematic review (CRD42021273301) of the impact of oral tetracycline-class antibiotics on AMR in normal flora.
[Clinical studies on doxycycline in the treatment of nongonococcal urethritis by Chlamydia trachomatis]. [2020]Twenty-one nongonococcal urethritis patients by Chlamydia trachomatis infection were treated with doxycycline (DOXY, Vibramycin) 200 mg/day orally for 2 weeks. The age of these patients were ranged from 17 to 52. C. trachomatis was eradicated 8(89%) of 9 cases on 3rd day and never reisolated on 7th day after treatment. Ten (83%) of 12 patients on 7th day and any patients on 14th day were not suffered from symptoms after treatment. Urethral discharge was not seen macroscopically, 11 (92%) of 12 patients on 7th day and any patients on 14th day. According to the criteria for urethritis requiring at least 4 WBC per high power field in urethral smear and/or first voided urine, the overall clinical efficacy rate was 44% (4/9) on 3rd day, 83% (10/12) on 7th day and 100% (9/9) on 14th day. No side effects were recognized in any cases. In conclusion, DOXY was thought to be useful and safe drug in the treatment of nongonococcal urethritis by C. trachomatis.
Antibiotic after sex could help curb infections. [2022]Doxycycline reduces risk of sexually transmitted diseases-but will it fuel drug resistance?
Comparison of spiramycin and doxycycline for treatment of Chlamydia trachomatis genital infections. [2021]We performed a single blind controlled multicenter study in which we compared the efficacy and safety of 100 mg of doxycycline versus those of 1 g (3 x 10(6) IU) of spiramycin given orally twice daily for 14 days in the treatment of culture-positive Chlamydia trachomatis genitourinary tract infections. A total of 367 patients were enrolled in the study, and 364 patients were evaluable for safety and 265 patients were evaluable for efficacy. The cure rate between treatment groups was not statistically significant, being 98% (125 of 128 patients) in the spiramycin group and 100% (133 of 133 patients) in the doxycycline group. Female patients who received spiramycin were more likely to report dysethesias that resolved after the completion of therapy. The results of the study show that spiramycin is an effective drug for the treatment of C. trachomatis infection and warrants further assessment over a shorter treatment period (7 days) and during pregnancy.
Doxycycline in the management of sexually transmitted infections. [2019]Doxycycline is a second-generation tetracycline, available worldwide for half a century. It is an inexpensive broad-spectrum antimicrobial agent largely used in the management of several bacterial infections, particularly involving intracellular pathogens, as well as in the treatment of acne or for the prophylaxis of malaria. Physicochemical characteristics of doxycycline (liposolubility) allow a high diffusion in the tissues and organs. It has high bioavailability and a long elimination half-life allowing oral administration of one or two daily doses. Over the last decade, the prevalence of bacterial sexually transmitted infections (STIs) (syphilis, chlamydiosis, gonorrhoea and Mycoplasma genitalium infections) has increased in most countries, mainly in MSM, many of whom are infected with HIV. In light of increasing prevalence of resistance towards first-line regimens of some STI agents and recently updated recommendations for STI management, doxycycline appears to be an attractive option compared with other available antibiotics for the treatment of some STIs due to its efficacy, good tolerability and oral administration. More recently, indications for doxycycline in STI prophylaxis have been evaluated. Considering the renewed interest of doxycycline in STI management, this review aims to update the pharmacology of, efficacy of, safety of and resistance to doxycycline in this context of use.
Antiviral activity of doxycycline against vesicular stomatitis virus in vitro. [2015]Doxycycline (Dox) is a tetracycline derivative with broad-spectrum antimicrobial activities that is used as an effector substance in inducible gene-expression systems. We investigated the antiviral activity of Dox against vesicular stomatitis virus (VSV) infection in cultured H1299 cells. Dox at concentrations of 1.0-2.0 μg ml(-1) significantly inhibited VSV replication and the VSV-induced cytopathic effect in dose-dependent manners, suggesting that Dox may have broader activity in inhibiting viral replication, in addition to its well-defined bacteriostatic activity. Dox exerted its antiviral effect at the early-mid stage of VSV infection, suggesting that it did not interfere with VSV infectivity, adsorption, or entry into target cells. These results indicate that Dox can inhibit VSV infection and may therefore have potential applications for the treatment of viral infections.
The use and safety of doxycycline hyclate and other second-generation tetracyclines. [2022]Tetracyclines have long been used to treat a wide variety of medical conditions, especially in the field of dermatology. Unfortunately, safety concerns, especially gastrointestinal (GI), have always been present. Other safety concerns have included tooth development in children, candidiasis, vestibular concerns, photosensitivity/phototoxicity, and more unusual adverse effects such as uncontrolled hypertension. This article first discusses the pharmacological development of the tetracyclines from the first to the second generation versions with an emphasis on the safety concerns, especially with regards to doxycycline hyclate (DH). Second, the adverse effects of the tetracyclines are discussed. Third, the favorable side effect profile of DH delayed release capsules (Doryx) is compared with DH powder contained in tablets (Vibramycin). Fourth, the increased use with a continued favorable safety profile is also discussed concerning the subantimicrobial dosing of DH for acne. Fifth, the safety of periodontic uses of DH is discussed. Last, the favorable safety profiles of the 2006 approved uses of an anti-inflammatory dose of 40 mg doxycycline for rosacea and an extended-release minocycline tablet for acne are also discussed.
Doxycycline-Induced Acute Pancreatitis: A Rare Adverse Event. [2020]Doxycycline is a broad-spectrum antibiotic belonging to the tetracycline group which acts by inhibiting bacterial protein synthesis. It is considered to be a relatively safe drug. We report a case of doxycycline-induced acute pancreatitis (DIAP) in an adult female patient who was started on the usual therapeutic dose 1 week before for acne vulgaris. The WHO causality assessment was possible, and the Naranjo scale confirmed it as "definite" adverse drug reaction. A brief literature review on case reports previously reporting DIAP has also been summarized.
[Clinical and pharmacokinetic researches of doxycyclin vibravenös in childhood (author's transl)]. [2013]Doxycyclin is one of the first efficacious depot antibiotics. It is used in two applications as Vibramycin (R) (peroral and Vibravenös (R) (parenteral). Doxycyclin has a favourable effect not only on different gram-positive and gram-negative bacteria but also on a lot of other germs as mycoplasms, rickettsias, protozoons and large viruses. The tissue invasions is a good one, because there is only a low fraction of free Doxycyclin and further a high lipid activity. Pharmacokinetic investigations of different age-groups show that good serum-levels can be reached because of the sensitivity of numerous germs. The levels are higher, as our experiences demonstrate, if the dose of 4 mg/kilo/weight is injected in two single doses. Our investigations are reported on 49 patients with diseases of the respiratory tract and on 25 patients with diseases of the urogenital tract. Doxycyclin was very useful especially in different forms of pneumonias. The results in infects of the urogenital tract are not so good ones. The compatibility of Doxycyclin can be characterised as very good for children.
Interim position statement on doxycycline post-exposure prophylaxis (Doxy-PEP) for the prevention of bacterial sexually transmissible infections in Australia and Aotearoa New Zealand - the Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine (ASHM). [2023]Recent studies have provided evidence for the effectiveness of using doxycycline (Doxy-PEP) to prevent bacterial sexually transmissible infections (STI), namely chlamydia, gonorrhoea, and syphilis, among gay, bisexual, and other men who have sex with men who have experienced multiple STIs. However, there remain several unanswered questions around potential adverse outcomes from Doxy-PEP, including the possibility of inducing antimicrobial resistance in STIs and other organisms, and the possibility of disrupting the microbiome of people who choose to use Doxy-PEP. This interim position statement from the Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine aims to outline the current evidence for Doxy-PEP, and to highlight potential adverse outcomes, to enable clinicians to conduct evidence-based conversations with patients in Australia and Aotearoa New Zealand who intend to use Doxy-PEP.