Issue: April 2017
March 10, 2017
4 min read
Save

Three-dose penicillin regimen not superior to single dose for syphilis in patients with HIV

Issue: April 2017
You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

A three-dose regimen of intramuscular benzathine penicillin G for syphilis, compared with a single dose, did not significantly improve outcomes in patients with HIV, data published in Clinical Infectious Diseases showed.

Perspective from

“The CDC’s sexually transmitted disease treatment guidelines advocate treating HIVinfected patients who have primary or secondary syphilis with the same number of doses of penicillin as [those used] for HIVuninfected patients. This recommendation has remained unchanged in the last several guideline cycles,” Roberto Andrade, MD, from Baylor College of Medicine, and colleagues wrote.  “To our knowledge, there have been no randomized controlled trials comparing the efficacy of a single dose of benzathine penicillin G with that of three doses of benzathine penicillin G administered at 1-week intervals for early syphilis in HIVinfected patients.”

Andrade and colleagues performed an open-label, randomized clinical trial on 64 HIVinfected patients with syphilis. Patients were randomly assigned to either a single-dose or three-dose regimen of benzathine penicillin G, with rapid plasma reagin (RPR) titers measured every 3 months. Researchers defined successful treatment as an RPR titer decrease of 2 dilutions or more over the course of a year.

Participants were overwhelmingly male (95%) and men who have sex with men (84%).

In the intention-to-treat analysis, the single-dose group had a success rate of 80% (28 of 35 patients), whereas the three-dose group had a 93% (27 of 29) success rate, the researchers reported (95% CI, 5% to 30%). However, in the per-protocol analysis, the researchers reported that the single-dose group had a 93% success rate (27 of 29 patients) and the 3-dose group had a 100% success rate (27 of 27 patients; absolute difference, 7%; 95% CI, 7% to 22%). Factors such as CD4 count, RPR titers and stage of syphilis did not affect outcomes, Andrade and colleagues wrote.

“Larger, ideally multicenter, studies are needed to confirm our findings,” Andrade and colleagues wrote. “In the meantime, our results support the current CDC recommendations to use a single dose of benzathine penicillin G for treatment of early syphilis in HIVinfected patients.”

In an accompanying editorial, A. Clinton White, Jr., MD, from the University of Texas Medical Branch, agreed that the findings support the CDC’s treatment guidelines, but with some reservation.

“Given these results, what conclusions can be drawn? Clearly, the bulk of evidence supports current recommendations to treat early syphilis with a single injection of benzathine penicillin regardless of the patient’s HIV status,” White wrote. “At the same time, the evidence to support this recommendation is not optimal. The difference between groups in the study by Andrade and colleagues raises concerns that a single injection might not be optimal. In the meantime, careful follow-up is essential regardless of treatment, and repeated courses of therapy may be needed for those patients who have not responded.” – by Andy Polhamus

 Disclosure: The researchers report no relevant financial disclosures.