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Linezolid for Syphilis Pilot Study

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ClinicalTrials.gov Identifier: NCT05548426
Recruitment Status : Not yet recruiting
First Posted : September 21, 2022
Last Update Posted : October 28, 2022
Universidad Peruana Cayetano Heredia
The University of Texas Health Science Center, Houston
Information provided by (Responsible Party):
Jeffrey Klausner, University of Southern California

Brief Summary:
The two specific aims are: AIM 1: To evaluate the efficacy of linezolid compared to benzathine penicillin G in the treatment of syphilis. AIM 2: Evaluate the susceptibility of Treponema pallidum historical and novel strains to linezolid.

Condition or disease Intervention/treatment Phase
Syphilis Drug: Group C, Linezolid 5 Drug: Group B, Linezolid 10d Drug: Group A, Penicillin Early Phase 1

Detailed Description:
This will be a randomized, open-label, non-comparative, adaptive pilot trial to evaluate the efficacy of two linezolid oral dosing schemes (600mg orally, twice a day, for five or ten days) compared to the current recommendation for the treatment of syphilis, benzathine penicillin G (single dose of 2.4 million units) in participants with and without HIV infection. In total, 60 participants will be enrolled across 2 clinical sites in Peru. Participants will participate in follow-ups to monitor clinical outcomes and serological response (RPR titer) at 1 month, 3 months, and 6 months. The investigators will also test linezolid against several types of syphilis strains in the lab to evaluate the microbicidal activity of linezolid in treating early syphilis. Study findings may identify an efficacious alternative syphilis treatment to penicillin that is effective for people living with HIV. Study findings may also help address the crisis of penicillin shortages, difficulty in administration, and offer options for those with penicillin allergy.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Pilot Study of Linezolid for Early Syphilis Treatment
Estimated Study Start Date : April 2023
Estimated Primary Completion Date : March 2025
Estimated Study Completion Date : March 2025

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Syphilis

Arm Intervention/treatment
Experimental: Linezolid 5 Day
Oral Linezolid 600mg, taken twice a day for 5 days
Drug: Group C, Linezolid 5
Oral Linezolid 600mg, taken twice a day for 5 days

Experimental: Linezolid 10 Day
Oral linezolid 600mg, taken twice a day for 10 days
Drug: Group B, Linezolid 10d
Oral Linezolid 600mg, taken twice a day for 10 days

Active Comparator: Benzathine Penicillin G
Single intramuscular injection of 2.4 million units of benzathine penicillin G
Drug: Group A, Penicillin
Standard of care benzathine penicillin G, one intramuscular injection, 2.4MU

Primary Outcome Measures :
  1. Response to Treatment [ Time Frame: 6 months ]
    Percentage of linezolid participants with a 4-fold decrease or greater in the serum RPR titer by 180 days after treatment

Secondary Outcome Measures :
  1. Treponema pallidum susceptibility [ Time Frame: 6 months ]
    Determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of linezolid against 6 historical and 3 clinical isolated strains

Information from the National Library of Medicine

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Ages Eligible for Study:   16 Years and older   (Child, Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • 16 years of age or older
  • Diagnosed cases of primary, secondary, or early latent syphilis with RPR titer ≥1:8 within 3 weeks prior to enrollment
  • Able to provide informed consent
  • For PLHIV: on treatment for HIV-infection and most recent viral load <200 copies/mL or most recent CD4 T-cell count >350 cells/mL

Exclusion Criteria:

  • Pregnancy or a positive pregnancy test on the day of enrollment
  • Participants who receive certain psychotropic medications, e.g., MAO inhibitors, SNRIs, SSRIs
  • Patients showing signs and symptoms of neurosyphilis
  • Serofast RPR titer
  • Recent (<7 days) or concomitant antimicrobial therapy with azithromycin, doxycycline, ceftriaxone, cefixime, or other beta lactam antibiotics (e.g. amoxicillin)
  • Linezolid or penicillin allergy

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05548426

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Contact: Jeffrey D Klausner, MD MPH (415) 876-8901 jdklausner@med.usc.edu

Sponsors and Collaborators
University of Southern California
Universidad Peruana Cayetano Heredia
The University of Texas Health Science Center, Houston
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Principal Investigator: Jeffrey D Klausner, MD MPH University of Southern California
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Responsible Party: Jeffrey Klausner, Clinical Professor, University of Southern California
ClinicalTrials.gov Identifier: NCT05548426    
Other Study ID Numbers: APP-22-04165
First Posted: September 21, 2022    Key Record Dates
Last Update Posted: October 28, 2022
Last Verified: October 2022
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: No IPD will be shared with other researchers

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
Keywords provided by Jeffrey Klausner, University of Southern California:
Treponema pallidum
Early Syphilis
Additional relevant MeSH terms:
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Treponemal Infections
Spirochaetales Infections
Gram-Negative Bacterial Infections
Bacterial Infections
Bacterial Infections and Mycoses
Sexually Transmitted Diseases, Bacterial
Sexually Transmitted Diseases
Communicable Diseases
Genital Diseases
Urogenital Diseases
Anti-Bacterial Agents
Anti-Infective Agents
Protein Synthesis Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action