Primary syphilis

MONDO:0002896

The subclinical or symptomatic stage of syphilis, occurring at an average of three weeks after contact with an infected individual. It manifests with one or more painless, indurated ulcers (chancres) of the skin or mucous membranes at the site of inoculation. These lesions heal spontaneously within a few weeks.

Also known as: early syphilis, symptomatic

16 clinical trials for this condition and its sub-types, 7 tagged with Primary syphilis itself.

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Where it sits in the disease tree

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↑ Syphilis (56)

Including sub-types (16) Tagged with Primary syphilis (7)

Trials to join now! 6 Not yet recruiting 1 Not yet finished but already full! 1 Completed 7 Terminated 1

New syphilis combo treatment tested in HIV patients – trial cut short

Disease control Stopped early

This study looked at two different antibiotic combinations for treating early syphilis in people living with HIV. One group received a single shot of ceftriaxone plus a week of doxycycline pills, while the other got the standard single shot of penicillin plus the same doxycycline…

Phase 4 • Sponsor: National Taiwan University Hospital • Aim: Disease control

Last updated Jun 27, 2026 09:08 UTC

Primary syphilis

Where it sits in the disease tree

New syphilis combo treatment tested in HIV patients – trial cut short