NCT07189208

Evaluation of Antimicrobial Prophylaxis to Prevent Syphilis in Pregnancy in Patients at Risk in Rio de Janeiro, Brazil

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 500 (estimated)
• Sponsor: University of California, Los Angeles · Academic / Other
• Sex: Female
• Age: 18 Years – 45 Years
• Healthy volunteers: Accepted

Summary

The goal of this clinical trial is to learn if benzathine penicillin works to prevent maternal syphilis. It will also learn about the safety of benzathine penicillin. The main questions it aims to answer are: * Does benzathine penicillin lower the rate of syphilis in pregnancy? * What medical problems do participants have when taking benzathine penicillin? Researchers will compare benzathine penicillin to routine care to see if benzathine penicillin works to prevent syphilis. Participants will: * Take benzathine penicillin or receive routine care during the third trimester of pregnancy * Visit the clinic once a month for injections and tests * Report any reactions to benzathine penicillin to the study team

Detailed description

Syphilis rates during pregnancy have been rising consistently in Brazil in the last decade, with a parallel increase in the rates of congenital syphilis. The state of Rio de Janeiro, in particular, has consistently had the highest rate of gestational syphilis in the country. It is critical to develop an intervention to reduce the risk of syphilis infection during pregnancy, especially for women most at risk of acquiring congenital syphilis. The investigators hypothesize that routine counseling on prevention of sexually transmitted infections (STIs) and the use of benzathine penicillin G (BPG) prophylaxis during pregnancy may help reduce the rates of syphilis in high risk pregnant populations and congenital syphilis. The investigators propose a randomized, unblinded clinical trial using BPG prophylaxis in pregnant women at higher risk of syphilis during pregnancy. The primary objective is to prevent the development of gestational syphilis and congenital syphilis through counseling on prevention of STIs, monthly treponemal and non-treponemal tests beginning in the 28th week of pregnancy and for those testing negative monthly IM injections of BPG, compared to counseling on prevention of STIs and monthly treponemal and non-treponemal tests beginning in the 28th week of pregnancy (enhanced standard of care). The primary maternal endpoint is a negative POC treponemal test and VDRL test at delivery confirming absence of maternal syphilis infection. The primary infant endpoint is absence of congenital syphilis. The study population is pregnant persons testing negative for syphilis at 28 weeks' of pregnancy but who are at higher risk of contracting syphilis during pregnancy. The study plans to enroll at the Hospital Federal dos Servidores do Estado or at maternity hospitals. Study participants with a viable pregnancy and no significant pregnancy complications until the time of enrollment who meet the inclusion and exclusion criteria are randomized to receive counseling about prevention of STIs, enhanced serological screening, and if testing negative receive 2.4 million units of BPG IM at 28 weeks of pregnancy (+/- one week), 32 weeks (+/- one week) and 36 weeks (+/- one week) or counseling and enhanced serological screening (enhanced standard of care). The duration of the study will be 3.5 years for recruitment of participants, 6 months to complete follow-up and one additional year for data analysis, data write up and publishing of results. The duration of participation for each pregnant person will be 4 to 5 months (from 28 weeks of gestational age to delivery). Infants will be followed in the neonatal period (first 4 weeks of life).

Conditions

• Congenital Syphilis

Interventions

Type	Name	Description
DRUG	Benzathine penicillin 2.4 million units	IM injection of BPG
BEHAVIORAL	Counseling and intensified testing.	Brazilian Ministry of Health guidelines for the prevention and diagnosis of maternal syphilis consist of counseling about STI prevention and syphilis testing at the first pre-natal consultation, at a subsequent consultation during or after 28 weeks of pregnancy, at delivery, and in case of abortion or stillbirth. In this study, intensified testing refers to treponemal and non-treponemal tests once every four weeks beginning as of the 28th week of pregnancy.

Timeline

• Start date: 2025-11-01
• Primary completion: 2030-01-31
• Completion: 2030-01-31
• First posted: 2025-09-23
• Last updated: 2025-11-18

Locations

4 sites across 1 country: Brazil