Condition (MeSH)
Syphilis
ClinicalTrials.gov lists 134 trials for Syphilis or a narrower condition beneath it. National Institute of Allergy and Infectious Diseases (NIAID) has the most among industry and government lead sponsors, with 6.
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Trials per phase (log scale)
118 of the 134 trials are tagged with Syphilis itself; the rest are tagged with a narrower condition beneath it.
When did Syphilis trials start? (26)
Shown in this order: most recent first, 1990 onwards. 2026 is partial: trials registered with a 2026 start date so far, not a full year. 1 trial is registered to start in 2027 or later, and not listed here.
Trials over time, by phase
- Phase 1
- Phase 1/2
- Phase 2
- Phase 3
- Phase 4
- Not applicable
- Observational
Top of scale: 18
Trials registered with a start date in each year, 1990 onward, stacked by phase (complete years only; the current partial year is in the table's notes). The table below lists the same counts, most recent years first.
| Year | Trials started |
|---|---|
| 2026 (partial year) | 12 |
| 2025 | 18 |
| 2024 | 11 |
| 2023 | 9 |
| 2022 | 2 |
| 2021 | 8 |
| 2020 | 5 |
| 2019 | 11 |
| 2018 | 5 |
| 2017 | 3 |
Showing 10 of 26 earlier years.
Forecast of the full-year count, planned starts included, not rows of this table: about 14 trials starting in 2026 and about 14 in 2027, the average of the 24 months through September, counted as registered and carried forward. The rows of this table count trials registered so far with a start date in the year, planned starts included; the forecast looks ahead to the count for the whole year, so it is not the same measure. In backtests on conditions of this size, forecasts made part-way through the year were typically off by about 28 percent and ran about 20 percent low against the count later registered; forecasts made before the year began were off by about 39 percent and ran about 37 percent low against the count later registered. These figures rest on a few years of history (target years from 2018 to 2025, varying by figure), place each condition as it is mapped today rather than as it was then, and score against a count for the newest year that was still being revised. Only condition series were scored.
Prediction, not a registry value: median of 36 months from start to primary completion across 18 trials still running at the 2026-10-09 snapshot; registered median of 27 months across 68 trials with a primary completion typed Actual. Source: ClinicalTrials.gov / AACT (CTTI), public domain.
What phase are Syphilis trials in? (7)
Shown in this order: phase order.
Show the trials by phase as a table
| Phase | Trials |
|---|---|
| Phase 1 | 1 |
| Phase 1/2 | 2 |
| Phase 2 | 11 |
| Phase 3 | 10 |
| Phase 4 | 16 |
| Not applicable | 50 |
| Observational | 44 |
How many Syphilis trials are recruiting? (8)
Shown in this order: the order a trial moves through, from not yet recruiting to unknown.
| Status | Trials |
|---|---|
| Not yet recruiting | 8 |
| Recruiting | 26 |
| Enrolling by invitation | 1 |
| Active, not recruiting | 5 |
| Completed | 68 |
Showing 5 of 8 statuses.
Status as registered on ClinicalTrials.gov. Each trial is counted once.
Which lead sponsors run the most Syphilis trials? (3)
Shown in this order: most trials first. Lead sponsors the registry classes as industry, NIH, US federal, other government or network. A hospital or university the registry files as government can appear here. Sponsors it classes as academic or other are shown on the full page, because that class cannot separate an institution from a named investigator.
| Sponsor | Trials |
|---|---|
| National Institute of Allergy and Infectious Diseases (NIAID) | 6 |
| Centers for Disease Control and Prevention | 3 |
| British Columbia Centre for Disease Control | 2 |
Which drugs are being tested for Syphilis? (5)
Shown in this order: most trials first. One row per drug, matched to a single molecule under all its names, ranked by number of trials.
| Drug | Trials |
|---|---|
| Benzathine Penicillin G | 12 |
| Carraguard (PC-515) | 3 |
| Cefixime | 3 |
| DOXY | 2 |
| Amoxicillin | 2 |
Interventions as named in the registry (10)
Shown in this order: most trials first.
| Drug | Trials |
|---|---|
| Doxycline | 7 |
| Ceftriaxone 4g/ 24h | 3 |
| Benzathine penicillin 2.4 million units | 3 |
| AB PREP | 3 |
| Intervention | 2 |
Showing 5 of 10 interventions.
These are the names sponsors entered on ClinicalTrials.gov that we have not matched to a single molecule. Some are drugs under a brand or code name; others are procedures, doses or arm labels.
Which serious adverse events do Syphilis trials report? (10)
Shown in this order: most subjects affected first. Subjects affected summed across trials, a cross-trial signal, not a rate.
| Adverse event | Subjects affected | Trials |
|---|---|---|
| Hospitalizations | 13 | 1 |
| Suicide attempt | 2 | 1 |
| Cat bite | 1 | 1 |
| Gastroenteritis | 1 | 1 |
| HIV | 1 | 1 |
Showing 5 of 10 adverse events.
Which publications cover Syphilis? (155)
Shown in this order: major-topic papers first, then newest, then most linked to trials.
| Publication | Journal | Year | Major topic |
|---|---|---|---|
| Implementation of an Opt-Out and Rapid Point-of-Care Syphilis Testing Program for Pregnant Patients Presenting to the Emergency Department. | Sexually transmitted diseases | 2025 | Yes |
| Jarisch-Herxheimer Reaction After Benzathine Penicillin G Treatment in Adults With Early Syphilis: Secondary Analysis of a Randomized Clinical Trial. | JAMA network open | 2025 | Yes |
| Gaps in the Care of Maternal and Congenital Syphilis in Hawai'i, 2022-2023. | The Pediatric infectious disease journal | 2025 | Yes |
| One Dose versus Three Doses of Benzathine Penicillin G in Early Syphilis. | The New England journal of medicine | 2025 | Yes |
| Evaluating the MedMira Multiplo® Complete Syphilis (TP/nTP) antibody test in a sexually transmitted infection clinic in Ottawa, Canada: increased rapid diagnosis and improved antibiotic stewardship. | BMC infectious diseases | 2025 | Yes |
Showing 5 of 155 publications.
Sub-conditions in MeSH (3)
MeSH descendants one level down with at least one trial, most trials first.
Not on this page
Not measured: delivery record.
Checked, with nothing recorded for this condition: prevalence and rare-disease identity.