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Syphilis clinical trials

The registry lists 126 studies for Syphilis across more than 10 countries. 34 are recruiting or about to start. 77 of them are mainly about Syphilis (how this is decided). Per ClinicalTrials.gov, last updated 2026-11-09.

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What changed in your saved searches, Oct 31 – Nov 6:

A study of drug A after surgery for early breast cancer

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Status

Completed
63
Recruiting
22
Status unknown
14
Not yet recruiting
11
Active, not recruiting
7
Terminated
6

Phase

Phase 4
17
Phase 3
10
Phase 2
9
Phase 1
3

Where

United States
39
Canada
12
China
9
Uganda
7
United Kingdom
4
France
4

Who runs them

National Institute of Allergy and Infectious Diseases (NIAID) (6) · University of Washington (4) · London School of Hygiene and Tropical Medicine (4) · National Taiwan University Hospital (3) · Peking Union Medical College Hospital (3) · University of North Carolina, Chapel Hill (3) · The University of Texas Health Science Center, Houston (3) · Population Council (3)

What is being tested here

Drugs under test in Syphilis studies, those with the most open studies first. Medicines only given beside them are not counted. How drugs are counted

DrugOpenPhase 3All
Doxycycline527
Cefixime114
Lidocaine111
Penicillin G Benzathine005
Penicillin G005
Chondrus crispus carrageenan003
Linezolid012
Azithromycin011
Ceftriaxone001

Coming up

3phase 3 studies under way
11studies finish main data collection within a year1 of them phase 3

Studies recruiting or running, from their records. “Main data collection” ends at the primary completion date, the sponsor’s own estimate, which often moves.

The 10 nearest, phase 3 first

Who these studies take

Of the 22 Syphilis studies recruiting now, 15 (68%) set no upper age limit and 6 (27%) stop at 75 or younger. 12 (55%) take children under 18. 6 (27%) are for women only and 1 (5%) for men only; 13 (59%) take healthy volunteers.

Recruiting studies that take each age, of 22
AgeWomenMen
104 (18%)1 (5%)
1821 (95%)15 (68%)
3019 (86%)14 (64%)
4019 (86%)14 (64%)
5017 (77%)12 (55%)
6516 (73%)12 (55%)
7516 (73%)12 (55%)
8516 (73%)12 (55%)

Across all 126 studies, recruiting or not: 21% stop at 75 or younger and 20% at 65; 34% take children; 20% are for women only and 22% for men only; 52% take healthy volunteers. From each study’s registry entry; the criteria on its page decide.

How long Syphilis studies take

Of 25 interventional studies with no phase under Syphilis, half reached primary completion within 29 months of starting, counting those still running.

Start to primary completionEvery sponsorIndustryNon-industry
Interventional, no phase29 mo9–42 · 25 studies——

Each figure is the month by which half the studies had reached primary completion, with the range in which the middle half did. Studies still running count until their last registry update; studies that stopped early are left out. Phase 1 includes early phase 1; observational means prospective or not stated, as retrospective and cross-sectional studies date a window of data rather than a study. How these figures are worked out

What changed recently

From the registry's own updates since Oct 11, 2026.

Newly registered2

Studies

Recruiting first, then most recently updated. Showing 50 of 126. Browse all 126 → or search them.