Obstetric Care Professionals Support the Availability and Use of Extencilline (Benzylpenicillin Benzathine) for the Treatment of Syphilis

Maternal Immunization Task Force

On January 17, 2024, the U.S. Food and Drug Administration (FDA) announced the availability of Extencilline (benzathine benzylpenicillin injection, powder, for suspension), a medication used to treat syphilis in pregnancy. The FDA has exercised enforcement discretion for the temporary importation and use of this treatment to mitigate the effects of the Bicillin L-A^® drug shortage. Extencilline has been determined to be equivalent to Bicillin L-A^® in terms of clinical use and dose. Extencilline is currently authorized and marketed in other countries.  

Our organizations support the use of Extencilline (Benzylpenicillin Benzathine) when Bicillin L-A^® is unavailable, for the treatment of syphilis in pregnant and lactating individuals who meet the clinical criteria. 

The FDA has provided distribution and administration information in a letter to healthcare professionals. Notably, the preparation and administration of Extencilline and the contraindications for prescribing differ from those for Bicillin-LA^®. Extencilline will only be available by prescription in the United States.  

Clinicians should continue to refer to the CDC STI Treatment Guidelines on appropriate management, including staging, of syphilis cases.