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Comprehensive Ambulatory Antibiotics for the Treatment of Congenital Syphilis

Comprehensive Ambulatory Antibiotics for the Treatment of Congenital Syphilis

Status
Not yet recruiting
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06921213
Acronym
Cares-1
Enrollment
90
Registered
2025-04-10
Start date
2025-10-01
Completion date
2027-06-30
Last updated
2025-05-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Syphilis, Congenital

Brief summary

CARES-1 is a randomised, open-label, phase II pharmacokinetic (PK) and safety study of ambulatory antibiotics for the treatment of neonates with all-risk asymptomatic congenital syphilis.

Interventions

Ten day course. Oral Linezolid dosed at 10mg/kg twice a day.

DRUGAmoxicillin

Ten day course. Oral Linezolid dosed at 50mg/kg twice a day.

Single IM dose 50,000iu/kg

Sponsors

University College Dublin
CollaboratorOTHER
University of Stellenbosch
CollaboratorOTHER
Malawi Liverpool Wellcome Programme
CollaboratorOTHER
University of Sydney
CollaboratorOTHER
Murdoch Childrens Research Institute
CollaboratorOTHER
MRC CTU at UCL
CollaboratorUNKNOWN
PHPT/AMS Laboratory, Faculty of Associated Medical Sciences, Chiang Mai University
CollaboratorUNKNOWN
London School of Hygiene and Tropical Medicine
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Masking description

It is not possible to blind the intervention to either participants or care providers given variation in route of administration and duration of therapy. Individuals assessing clinical and laboratory outcomes will be blinded to study group.

Eligibility

Sex/Gender
ALL
Age
0 Days to 7 Days
Healthy volunteers
No

Inclusion criteria

1. Infants at risk of congenital syphilis at birth defined as: 1. an infant born to a mother who tests positive for syphilis in pregnancy using registered and licensed locally-available diagnostic tests for example but not limited to a Treponemal rapid POCT, an RPR or both. AND 2. the mother is untreated in the current pregnancy defined as: i. she tested positive at antenatal care and received no treatment OR ii. she was never tested during antenatal care OR iii. she tested negative at antenatal care and positive on re-testing at delivery OR c. the mother is inadequately treated in the current pregnancy defined as: i. Having received a non-penicillin based treatment regimen; and/or ii. Does not have documentation of 3 doses of IM Benzathine Penicillin, given 7-10 days apart, with the last dose given \> 30 days prior to delivery OR b. The mother was adequately treated in the current pregnancy BUT considers herself at risk of re-infection following a midwife delivered explanation of risk (partner treatment, multiple partners etc). 2. Infants who are asymptomatic for a diagnosis of congenital syphilis following application of a clinical proforma by the study team (Appendix 1) 3. Infants who are less than \<= 7 days of life AND with a post-menstrual age (PMA) of 34-42 weeks (Appendix 2). 4. Infants who are tolerating enteral feeds, including if they are being administered by an NG tube.

Exclusion criteria

\- 1. The infant's clinical condition at birth or prior to randomisation requires ongoing (\> 48 hours) treatment with antibiotics with the potential for anti-treponemal activity i.e. B-lactams, Cephalosporins, Carbapenems. 2\. They have a birthweight \<2kg 3. They are nil by mouth. 4. They have a life-limiting congenital anomaly

Design outcomes

Primary

MeasureTime frameDescription
Time above MIC in serumFrom enrolment through to day 10 of the studyTime above MIC of T. pallidum for the dosing interval in serum
Time above MIC in CSF10 daysTime above MIC in CSF throughout the dosing interval
Adverse EventsAssessed from enrolment through to 24 weeksThe proportion of individuals experiencing an adverse event through to week 24. The trial will record SAE, SUSARS, and drug related AEs of grade 3 or higher.

Secondary

MeasureTime frameDescription
Clinical OutcomeEnrolment through to week 24Proportion of infants who have clinical or laboratory evidence of congenital syphilis as adjudicated by an expert committee, blinded to treatment allocation, based on clinical and laboratory data.
AUC/MIC Ratio in serumEnrolment through to day 10Proportion of individuals achieving an AUC/MIC ratio ≥100 in serum
AUC/MIC Ratio in CSFEnrolment through to day 10Proportion of individuals achieving an AUC/MIC ratio ≥100 in CSF

Countries

Indonesia, Malawi, South Africa

Contacts

Primary ContactSarah Prentice
sarah.prentice@lshtm.ac.uk+4420 7636 8636

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026