The study ANRS 174 Doxyvac is a clinical trial that will use Combined Prevention of Sexually Transmitted Infections (STIs) in Men Who Have Sex with Men and using oral TDF/FTC for HIV Pre-Exposure Prophylaxis (PrEP) and vaccination with Bexsero.
This is a randomized study with a factorial design for the 2 biomedical interventions (interventions 1 and 2). Subjects will be randomized and assigned to two different interventions: * Intervention 1: PEP with doxycycline or no PEP. Subjects will be randomized 2/1 to receive doxycycline PEP or no PEP * Intervention 2: Meningococcal B vaccine (Bexsero®) or no vaccine Subjects will be randomized 1/1 to received 2 doses of Bexsero® vaccine (at the first visit and two months later) or no vaccine Participants will be randomized in one of the following arms: * Arm 1: doxycycline and Bexsero® vaccine (240 participants) * Arm 2: doxycycline and no Bexsero® vaccine (240 participants) * Arm 3: no doxycycline and Bexsero® vaccine (120 participants) * Arm 4: no doxycycline and no Bexsero® vaccine (120 participants) Randomization will be stratified by whether or not the participant enters in the ancillary study "intestinal microbiota".
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
556
2 tablets of doxycycline 100 mg (monohydrate form) will be taken orally after each risk sexual intercourse, ideally within 24 hours after sex and no more than 72 hours. PEP should not be taken more than 3 times over a 7 days' period. If a participant has risk sexual intercourse for several consecutive days, PEP should be taken at least 48 hours apart and no more than 3 times 2 tablets over 7 days. A maximum of 3 intakes of 2 tablets will be allowed over a period of 7 days.
1st injection of Bexsero® vaccine at inclusion visit, 2nd injection at week 8.
Hôpital Bichat
Paris, France
Hôpital Hôtel Dieu
Paris, France
Hôpital Saint-Louis
Paris, France
Hôpital Saint-Antoine
Paris, France
For intervention 1 (with or without doxycycline PEP) : 1st occurence of chlamydia or syphilis after the enrolment visit (Day 0)
Intervention 1 (with or without doxycycline PEP) is the first episode of chlamydia or syphilis after the enrolment visit (Day 0) (chlamydia and syphilis diagnosed at the enrolment visit will not be included in the primary endpoint). Chlamydia détection will be performed by polymerase chain reaction.Syphilis détection will be performed by antigen.
Time frame: Month 24
For intervention 2 with or without Bexsero® vaccine : 1st occurence of gonorrhea reported one month after the second vaccine injection
Intervention 2 (with or without Bexsero® vaccine) is the first episode of gonorrhea reported one month after the second vaccine injection, so starting at the month 3 visit (gonorrhea episodes diagnosed at the enrolment visit and before the month 3 visit will not be included in the primary endpoint). In these analyses, subject follow-up will be right-censored at the time of the first STI. Gonorrhea détection will be performed by polymerase chain reaction.
Time frame: Month 24
- Occurrence of a first episode of each of the bacterial STIs as well as cumulative incidence of each bacterial STIs
\- Occurrence of a first episode of each of the bacterial STIs as well as cumulative incidence of each bacterial STIs (syphilis, chlamydia; gonorrhoea and Mycoplasma genitalium) during the trial. In that case, the entire follow-up will be considered. Chlamydia détection will be performed by polymerase chain reaction. Syphilis détection will be performed by antigen. Mycoplasma genitalium be performed by polymerase chain reaction. Gonorrhea détection will be performed by polymerase chain reaction.
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Occurrence of a new episode of anal or urinary gonorrhoea.
\- Occurrence of a new episode of anal or urinary gonorrhoea. Gonorrhea détection will be performed by polymerase chain reaction.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Hôpital pitié Salpetrière
Paris, France
Hôpital Pitié-Salpétrière
Paris, France
Hôpital Necker-Enfants Malades
Paris, France
Hôpital Européen Georges Pompidou
Paris, France
Hôpital Tenon
Paris, France
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Occurrence of a first symptomatic episode of chlamydia infection or gonorrhea
\- Occurrence of a first symptomatic episode of chlamydia infection or gonorrhea at urinary or anal sites. Chlamydia détection will be performed by polymerase chain reaction. Gonorrhea détection will be performed by polymerase chain reaction.
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Proportion of patient with Methicillin-Resistant Staphylococcus Aureus and/or doxycycline resistant Staphylococcus aureus from throat. Fecal carriage of Extended-Spectrum Beta-Lactamase-producing Enterobacteriaceae Composition of intestinal microbiota
detection from throat swab of carriage of MRSA (methicillin-resistant Staphylococcus aureus) and/or doxycycline resistant Staphylococcus aureus, fecal carriage of ESBL (extended-spectrum beta-lactamase) -producing Enterobacteriaceae, and composition of the intestinal microbiota), all détected by polymerase chain reaction assay
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Incidence of clinical and biological adverse events
Proportion of patients experiencing a clinical or biological adverse events (ANRS scale)
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Proportion of patients taking doxycycline
Adherence will be evaluated by doxycycline pills taken by patients
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Concentration of doxycycline in hair
Adherence will be evaluated by détection of doxycyclin in hair
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Proportion of patients with Antibiotic susceptibilities of all strains of NG (Neisseria gonorrhoeae), CT (chlamydiae trachomatis), MG (mycoplasma genitalium)
identification of Antibiotic susceptibilities of all strains of NG (Neisseria gonorrhoeae), CT (chlamydiae trachomatis), MG (mycoplasma genitalium) to doxycycline, macrolides, fluoroquinolones and third generation cephalosporin will be performed by PCR (polymerase chain reaction assay)
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Rate of cured STIs after treatment with or without PEP.
declaration of illnesses from infection to healing
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Incidence of resistance to antibiotics of Neisseria gonorrhoeae with or without doxycycline.
Proportion of participants with resistance to antibiotics of Neisseria gonorrhoeae will be evaluated by polymerase chain reaction to detect mutations
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Incidence of Serum bactericidal activity against meningococcal and gonococcal antigens over time in participants of Bexsero®'s arm.
Proportion of participants with Serum bactericidal activity against meningococcal and gonococcal antigens
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Incidence of clinical and biological adverse events following Bexsero® vaccine.
Proportion of participants experiencing a clinical and biological adverse events following Bexsero® vaccine (ANRS scale)
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Prevalence and incidence of meningococcal carriage in pharyngeal, anal and urine swabs.
detection of meningococcal carriage in pharyngeal, anal and urine swabs will be performed
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Impact of PEP or Bexsero® vaccine on sexual behaviour
rates of condom use for receptive anal intercourse, number of sexual partners and number of sex acts over time
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24
- Incidence of HIV infection with both prophylaxis strategies.
HIV infection will be tested by serology and western blot assay
Time frame: Month 2, Month 3, Month 6, Month 12, Month 18, Month 21, Month 24