Clinical trial NCT02611765: Syphilis Response to Higher Penicillin Dosage: The 2.4 Versus 7.2 Study
Official title: Syphilis Response to Higher Penicillin Dosage in HIV Co-Infected Patients
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Syphilis
Lead sponsor: Baylor College of Medicine
Sponsor class: OTHER
First posted: 2015-11-23
Enrollment: 64
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Syphilis remains a significant health problem worldwide, with an estimated 10.6 million new cases per year. Due to shared transmission route and risk factors, co-infection with syphilis and Human Immunodeficiency Virus (HIV) is not uncommon. Several studies have evaluated the response to syphilis treatment in HIV-infected patients. They support the claim that patients with HIV have a slower decrease in syphilis antibody titers, and that they may progress to neurosyphilis in earlier stages.

The Center for Disease Control and Prevention's Sexually Transmitted Disease Treatment Guidelines has advocated treating HIV-infected patients who have primary, secondary syphilis or early latent syphilis with the same doses of penicillin as for HIV-uninfected patients (single dose of 2.4 million units of benzathine penicillin G). The investigators designed a randomized controlled trial in order to compare the efficacy of three- versus single-dosed regimens of intramuscular benzathine penicillin G (BPG) for the treatment of early syphilis in HIV-infected patients.

Detailed description: The investigators conducted a prospective, randomized, open label study at three clinical sites including Thomas Street Health Center and North West Clinic (Harris Health System), and the Michael E. DeBakey Veterans Affairs Medical Center in Houston, Texas. After obtaining written informed consent, the investigators randomly assigned patients to either a single intramuscular injection of 2.4 million units of BPG (standard therapy) or three doses (enhanced therapy) of intramuscular BPG administered weekly (a total of 7.2 million units).

Patients were eligible for inclusion in the study if they were 18 years of age or older and had a diagnosis of HIV. The diagnosis of syphilis was made based on a positive Rapid Plasma Reagin (RPR) and treponema pallidum particle agglutination tests. Patients with primary, secondary and early latent syphilis were included.

Exclusion criteria were history of penicillin allergy, diagnosis of late latent syphilis, neurosyphilis, and antibiotic use with significant activity against Treponema pallidum within the preceding two weeks.

Follow-up period was 12 months. Serum samples were obtained at initial visit and follow-up visits every 3 months for serological testing for syphilis. Treatment success was defined as a decrease in RPR titer of \>= 2 dilutions (4-fold) from the initial RPR titer during the follow-up period.

Both intention-to-treat and per-protocol analyses were performed

Eligibility criteria: Inclusion Criteria:

* Diagnosed with HIV by ELISA and confirmed by Western blot
* Positive Rapid Plasma Reagin and treponema pallidum particle agglutination tests

Exclusion Criteria:

* History of penicillin allergy
* Diagnosis of late latent syphilis
* Diagnosis of neurosyphilis
* Antibiotic use with significant activity against Treponema pallidum within the preceding two weeks

Primary outcomes:
measure: Treatment Success Defined as a Decrease in Rapid Plasma Reagin (RPR) Titer of >= 2 Dilutions (4-fold)
timeFrame: 12 months
Secondary outcomes:
Other outcomes:
Locations:
Study officials:
affiliation: Assistant Professor (Medicine: Infectious Disease)
name: Jose A Serpa-Alvarez, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Andrade R, Rodriguez-Barradas MC, Yasukawa K, Villarreal E, Ross M, Serpa JA. Single Dose Versus 3 Doses of Intramuscular Benzathine Penicillin for Early Syphilis in HIV: A Randomized Clinical Trial. Clin Infect Dis. 2017 Mar 15;64(6):759-764. doi: 10.1093/cid/ciw862.