Lidocaine for Syphilis

(LIMIT Trial)

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 3

Recruiting

Sponsor: Washington University School of Medicine

Pivotal Trial (Near Approval)

Prior Safety Data

Trial Summary

What is the purpose of this trial?

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.

Research Team

Eligibility Criteria

The LIMIT Trial is for adults over 18 with a confirmed syphilis diagnosis who are receiving their first injection if they require multiple weekly injections. It's not suitable for individuals with penicillin allergies.

Inclusion Criteria

I have been diagnosed with syphilis confirmed by tests.

I am 18 years old or older.

I am starting my first of three weekly injections for syphilis treatment.

Treatment Details

Interventions

• Lidocaine (Local Anesthetic)

Trial Overview This trial tests whether adding lidocaine to the benzathine penicillin G (BPG) injection reduces pain compared to using normal saline. Participants will receive two BPG injections, one with lidocaine and one with saline, in a randomized, double-blinded manner.

Participant Groups

Group I: Lidocaine + Benzathine Penicillin G Arm Experimental Treatment 1 Intervention

0.5ml 1% lidocaine solution added to prefilled 1.2 million units Benzathine Pencillin G syringe which will be injected once into the gluteal muscle of the study participant, the side (left or right) to be randomly assigned with the control assigned to the other gluteal muscle.

Group II: Normal Saline + Benzthine Penicillin G Arm Placebo Group 1 Intervention

0.5ml normal saline solution added to prefilled 1.2 million units Benzathine Pencillin G syringe which will be injected once into the gluteal muscle of the study participant, the side (left or right) to be randomly assigned with the study arm assigned to the other gluteal muscle.

Who Is Running the Clinical Trial?

Washington University School of Medicine

Lead Sponsor

Trials

2,027

Recruited

2,353,000+

David H. Perlmutter

Washington University School of Medicine

Chief Executive Officer since 2015

MD from Washington University School of Medicine

Paul Scheel

Washington University School of Medicine

Chief Medical Officer since 2022

MD from Washington University School of Medicine