Pfizer’s multi-year effort to stabilize its U.S. penicillin supply has hit an unexpected hitch after particulate concerns prompted a recall of the company’s long-acting injectable form of the ubiquitous antibiotic.
The latest turn in the shortage saga comes at an inopportune time, as rates of syphilis have been on the rise in newborns in recent years. Pfizer’s product—known as Bicillin L-A—is the penicillin product most often used to treat syphilis in pregnant women.
“Pfizer is voluntarily recalling multiple lots of Bicillin L-A (penicillin G benzathine injectable suspension) in the U.S. at the user level due to the identification of particulates during visual inspection,” the company said in an emailed statement. Since initiating the recall of Bicillin on July 10, Pfizer has not received any adverse event reports linked to the pulled product batches.
Pfizer initiated the recall after determining that particulates had made their way into the drug via stoppers supplied from an “external vendor,” the company noted in its emailed statement.
“We fully recognize the importance of this medicine for patients and are working as quickly as possible to resolve the matter,” Pfizer added.
The action covers seven lots of 1.2 million units/2 mL injections and five lots of the 2.4 million units/4 mL presentation, according to a recall notice (PDF) Pfizer sent out to customers late last week.
The move is expected to cause a “near-term stock out of Bicillin L-A,” Pfizer said in its statement, with the drugmaker now allocating “limited quantities of inventory to customers during this period as we establish a path to full recovery.”
Pfizer defined supply recovery as having “8 weeks of inventory available in our own distribution centers, in addition to product fully stocked in the distribution chain.”
In a separate letter (PDF) to customers, Pfizer committed to providing an update on the supply situation “no later than mid-August.”
The 1.2 million unit and 2.4 million unit presentations of Bicillin are currently listed as having limited availability on the FDA’s drug shortage database, while another 600,000-unit format is marked unavailable. Both the FDA and the American Society of Health-System Pharmacists—which runs its own independent drug shortage tracker—noted that Pfizer plans to release more of the 600,000-unit syringes by October.
The timing of Pfizer’s recall and the associated supply constraints dovetail with a concerning spike in newborn syphilis cases and sexually transmitted infections (STIs) in general in the U.S.
According to the CDC, more than 3,700 babies were born with syphilis in 2022, more than ten times the number of cases observed in 2012.
“The increase in newborn syphilis follows rising syphilis cases among women of reproductive age combined with social and economic factors that create barriers to high-quality prenatal care and ongoing declines in the prevention infrastructure and resources," the CDC said in late 2023.
Apart from children being born with the STI, syphilis during pregnancy can also lead to tragic outcomes like miscarriage, stillbirth and infant death, the CDC cautioned at the time.
Meanwhile, this isn’t the first time Pfizer has run into issues with its Bicillin supply.
Back in April 2023, the FDA reported a nationwide penicillin shortage, and by June of that year, Pfizer was alerting hospital customers that it expected stock of its Bicillin prefilled syringes to be spread thin.
At the time, Pfizer attributed the supply squeeze to a “complex combination” of factors, including significant demand for the product.
Pfizer said it would prioritize manufacturing of its long-acting penicillin product to help meet the needs of its customers. In the interim, the FDA also cleared imports of comparable penicillin products from France’s Laboratoires Delbert and Portugal’s Laboratórios Atral.
The latter product from Astral, known as Lentocilin, is being sold by Mark Cuban’s Cost Plus Drugs in the U.S. Imports of both products continue to be authorized, CNN reports.