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Recruiting Phase 3 NCT06391125

NCT06391125 LIMIT Trial - Lidocaine With Intramuscular Injection of Benzathine Penicillin G for Treponema Pallidum Treatment

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Clinical Trial Summary
NCT ID NCT06391125
Status Recruiting
Phase Phase 3
Sponsor Washington University School of Medicine
Condition Syphilis Infection
Study Type INTERVENTIONAL
Enrollment 48 participants
Start Date 2024-07-01
Primary Completion 2025-12

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
normal SalineLidocaine

Eligibility Fast-Check

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What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 48 participants in total. It began in 2024-07-01 with a primary completion date of 2025-12.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

There is evidence to suggest that lidocaine can help reduce the pain associated with intramuscular injections of benzathine penicillin G (BPG) or Bicillin, used to treat syphilis infections. A study published in the Journal of Family Practice in 2001 compared the pain experienced during bicillin injections with and without the use of lidocaine. The study found that patients who received lidocaine injections before receiving bicillin reported significantly less pain compared to those who received bicillin injections without lidocaine. Per the International Union against Sexually Transmitted Infections (IUSTI) European Guidelines for syphilis management, lidocaine has been used as a diluent for BPG since 1998. In the United States (US), BPG often comes prepackaged and lidocaine is unable to be used as a diluent with the same ease as it is in Europe. In light of this, the investigators propose a randomized controlled trial of benzathine penicillin G with and without lidocaine to quantify any site pain reduction with lidocaine in patients being treated for syphilis. This study is a randomized, double blinded, placebo controlled trial. During this study, patients needing BPG treatment for syphilis will be screened for any penicillin allergies and consented to their participation. Each participant will receive 2 injections of BPG, 1.2 million units each (2x1.2 million units = 2.4 million units, the standard dose for syphilis treatment), as intramuscular injections, one in each gluteal muscle, with one of the injections randomly having 0.5ml of 1% lidocaine added while the other has 0.5 ml normal saline solution. The side of each injection will be randomized by the medical assistant (MA)/nurse filling the vials and the injecting MA will be blinded, as well as the study participant, as to which vial contains lidocaine and which contains normal saline. The participants will then be asked to rate their pain from 0-10 on each site of injection at 10 minutes post injection, then again at 24 hours after injection via email electronic survey (via RedCap). The differences in pain from the two injections will be compared and analyzed to see if lidocaine reduces pain associated with BPG injections compared to the control of normal saline added to BPG.

Eligibility Criteria

Inclusion Criteria: * Adults 18 years of age or above * Confirmed syphilis diagnosis (reactive RPR with confirmatory treponemal testing) * Receiving first injection in series if patient requires 3x weekly injections for syphilis treatment Exclusion Criteria: * Penicillin allergy (anaphylaxis) * Lidocaine allergy (anaphylaxis) * Second or third injection in series if patient requires 3x weekly injections for syphilis treatment * Pregnancy

Contact & Investigator

Central Contact

Joseph Cherabie, MD

✉ jcherabie@wustl.edu

📞 7202858096

Frequently Asked Questions

Who can join the NCT06391125 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Syphilis Infection. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06391125 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 48 participants.

Is NCT06391125 currently recruiting?

Yes, NCT06391125 is actively recruiting participants. Contact the research team at jcherabie@wustl.edu for enrollment information.

Where is the NCT06391125 trial being conducted?

This trial is being conducted at St Louis, United States.

Who is sponsoring the NCT06391125 clinical trial?

NCT06391125 is sponsored by Washington University School of Medicine. The trial plans to enroll 48 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: September 2026  ·  Data Methodology