(P110) SYPHILIS TREATMENT REGIMENS IN CALIFORNIA DURING THE 2023 BENZATHINE PENICILLIN G SHORTAGE

Wednesday, September 18, 2024

4:15 PM - 5:15 PM EST

Primary Author(s)

EM

Elizabeth B. Moran, MPH (she/her/hers)

Epidemiologist Evaluator
California Department of Public Health

Co-Author(s)(s)

Eric C. Tang, MD, MPH

Public Health Medical Officer
California Department of Public Health, California, United States
KJ

Kathleen Jacobson, MD

California Department of Public Health, United States
Nicole O. Burghardt, MPH (she/her/hers)

STD Control Branch, STI Epidemiology Unit Chief
California Department of Public Health, United States
RS

Robert Snyder, PhD, MPH

STD Control Branch, Surveillance, Epi, Assessment and Evaluation Section Chief
California Department of Public Health
Sacramento, California, United States

Background:
Benzathine penicillin G (BIC) is the recommended treatment for syphilis, delivered intramuscularly. Doxycycline is an alternative oral treatment for non-pregnant people. In April 2023 the U.S. FDA announced a BIC shortage. We compared syphilis treatment regimens before and during the BIC shortage.

Methods:
We assessed treatment regimens documented for syphilis infections in California (excluding neurosyphilis and LA and SF counties) from July-December 2022 to July-December 2023, and by stage and gender using Pearson’s chi-squared.

Results:
In July-December 2022 and July-December 2023, 10,550 and 8,790 syphilis infections were identified, respectively. Treatment with doxycycline increased (9% to 38%), and BIC decreased (76% to 41%) comparing July-December 2022 to July-December 2023 (p < 0.0001); this was true for early (doxycycline 10% to 40%, BIC 84% to 53%) and late, unknown duration syphilis (9% to 37%, 70% to 34%) and among cisgender men (9% to 40%, 77% to 39%), cisgender women (10% to 34%, 75% to 45%), and transgender, gender non-conforming, and non-binary people (TGNCNB) (8% to 48%, 82% to 44%) (p < 0.0001). During the BIC shortage (July-December 2023), a significantly higher proportion of cisgender women received BIC compared to cisgender men (44% vs. 39%, p<0.0001); BIC treatment did not differ significantly for TGNCNB (46%) compared to cisgender men or women (p>0.05). A significantly higher proportion of cisgender men (40%) and TGNCNB (48%) received doxycycline compared to cisgender women (33%) (p < 0.001). Doxycycline treatment did not differ significantly between TGNCNB people and cisgender men (p>0.05).

Conclusion:
Doxycycline was used more often, and BIC was used less often to treat syphilis during the 2023 BIC shortage compared to 2022, and differences in treatment regimen were noted by key stratifications. Given doxycycline requires adherence to 14- or 28-day course compared to injectable BIC, increased doxycycline use during BIC shortages could impact syphilis cure and transmission rates and should be evaluated.