Multicentre Study Evaluating the Efficacy of a 7-day Course of Doxycycline for the Treatment of Asymptomatic Anal Lymphogranuloma Venereum.

Multicentre Study Evaluating the Efficacy of a 7-day Course of Doxycycline for the Treatment of Asymptomatic Anal Lymphogranuloma Venereum

Lymphogranuloma venereum (LGV) is a sexually transmitted infection (STI) caused by the L genotypes of C. trachomatis. Proctitis is the main clinical manifestation of infection in the current LGV epidemic. However, recent European studies reported that about 25% of the anal LGV infections are asymptomatic. In France, asymptomatic anal LGV increased from 36.1% (44/124) in 2020 to 52.4% (66/126) in 2022. LGV testing is recommended on all C. trachomatis-positive anorectal specimens because therapy of extended duration is required. Patients with anal C. trachomatis infection should be treated initially with 7-day course of doxycycline (200 mg per day orally) while awaiting the results of LGV testing. Treatment should be extended to 21 days in cases of LGV according to current European and USA guidelines for LGV treatment. This regimen is indicated for symptomatic and asymptomatic anorectal LGV, with a 98.5% treatment efficacy. However, there is no obvious biological basis for prolonged treatment of asymptomatic LGV. Three recent retrospective studies showed that a 7-day course of doxycycline was effective for the treatment of asymptomatic LGV, with microbial cure ranging from 97% (38/39) to 100% (54/54). The objective of this study is to evaluate the efficacy (microbiological cure rate) of a 7-day course of doxycycline 200 mg daily orally for the treatment of asymptomatic anal LGV infection, four weeks after treatment initiation.

Inclusion Criteria:

• Age ≥ 18 years
• Male sex at birth
• LGV-positive result on anal specimen using Nucleic Acid Amplification Test at screening
• Having taken at least doxycycline for two days (i.e 400 mg of doxycycline)
• Not having taken more than 7 days of doxycycline 200 mg per day
• No more than 12 days between the date of sampling and date of inclusion
• No anorectal symptoms
• Individual available for participation and follow-up during the four weeks required for the study
• Affiliate or beneficiary of a social security scheme
• Free written informed consent signed by the participant or by a legal representative (in the event of the participant's inability to consent) and the investigator (no later than the day of inclusion and before any examination required by the research).

Exclusion Criteria:

• Individual with anorectal symptoms
• Antibiotic treatment with antichlamydial activity (fluoroquinolones, macrolides-lincosamides-streptogramins, tetracyclines and rifampicin) within 28 days before the screening visit
• Use of doxycycline post-exposure prophylaxis (Doxy-PEP)
• Participation in another study
• Individual under a measure of legal protection measure (safeguard of justice, guardianship or curatorship) or unable to consent
• Refusal to participate in the study
• Mental state rendering the person giving consent incapable of understanding the entirety of the trial
• Participant detained by judicial or administrative decision.
• Individual receiving an anticoagulant therapy
• Individual with a history of known hypersensitivity to doxycycline or any other antibiotic of the tetracycline family or allergy to any of the excipients (Hydrogenated castor oil, povidone, anhydrous colloidal silica, magnesium stearate, microcrystalline cellulose, sodium carboxymethyl starch (type A)).
• Individual treated with retinoids by general route.
• Individual receiving 10,000 IU of vitamin A per day or more
• Individual being a relative of the investigator or a relative of someone from the team directly involved in the trial, including assistant doctors, pharmacists, nurses, and trial coordinators