Comparisons of Treatment Responses of Early Syphilis to Benzathine Penicillin G With or Without Doxycycline

National Taiwan University

Status: Enrolling

Conditions: Early Syphilis, Latent, Serological Relapse After Treatment

Treatments: Drug: Benzathine Penicillin G; Drug: Doxycycline Capsule

Study type: Interventional

Funder types: Other

Identifiers

NCT06069141

202305061MINA

Details and patient eligibility

About

This randomized controlled superiority study will be conducted during 2023-2025. The eligible participants are adult people living with HIV (PLWH) who are newly diagnosed with early syphilis. Participants will be randomized in a 1:1 ratio to receive single-dose benzathine penicillin G (BPG) (2.4 MU intramuscularly once) plus doxycycline (100 mg orally twice daily for 7 days) or single-dose BPG. The primary outcome is serologic response, defined as a decline of rapid plasma reagin (RPR) titer by 4-fold or greater, at week 24 and week 48; and the secondary outcomes include microbiologic response of syphilis and bacterial sexually transmitted infections (STIs) assessed by nucleic-acid amplification test (NAAT) at week 4.

Enrollment: 688 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• People living with HIV (PLWH) aged ≥18 years with early syphilis
• Confirmed by a positive RPR titer with a reactive TPPA assay

Exclusion criteria

• PWH with RPR titers of <4
• Exposure to antibiotics with activity against T. pallidum within the preceding 4 weeks (penicillin, 3rd cephalosporin, doxycycline, macrolides)
• A known or suspected infection requiring additional treatment with an antimicrobial active against T. pallidum (penicillin, 3rd cephalosporin, doxycycline, macrolides)
• Testing positive for C. trachomatis and M. genitalium, for which doxycycline or macrolide was administered
• A history of intolerance to penicillin or doxycycline
• PLWH have already participated in this study
• Pregnancy

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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688 participants in 2 patient groups, including a placebo group

single-dose BPG plus doxycycline

Active Comparator group

Description:

single-dose benzathine penicillin G (2.4 MU intramuscularly once) plus doxycycline (100 mg orally twice daily for 7 days)

Treatment:

Drug: Doxycycline Capsule

Drug: Benzathine Penicillin G

single-dose BPG

Placebo Comparator group

Description:

single-dose benzathine penicillin G (2.4 MU intramuscularly once)

Treatment:

Drug: Benzathine Penicillin G