Sanofi Genzyme on Monday told doctors and pharmacists to return more than 12,000 syringes filled with an injectable arthritis gel because it was contaminated, as the Cambridge-based biotech elevated its “product hold” of last week to a recall.
A lot containing 18,000 gel-filled syringes of Sinvisc-One tested positive for microbial contamination, said Ashleigh Koss, a spokeswoman for the company’s French parent, Sanofi SA. Only 12,380 of the syringes were distributed, all in the United States.
Syringes from the lot, which bears the identification number 7RSL021, were associated with an unexpected surge in “adverse events,” according to a product hold letter sent to health care providers. The drug was made at the company’s plant in Ridgefield, N.J.
The company has declined to specify how the lot got contaminated or what the medical problems were, but said there were no deaths associated with the problem. Because some of the distributed syringes may not have been used on patients yet, the drug maker wanted doctors, pharmacists, and clinics to return them to prevent further problems.
The syringes were distributed in 36 states, including Massachusetts, between Oct. 25 and Nov. 7, another Sanofi spokeswoman said on Friday. She said the side effects were “consistent with documented adverse events in the product label.”
In the past, the company has said the most common side effects are pain, swelling, heat, redness, and fluid build-up in or around the knee.
Approved by the Food and Drug Administration in 2009, Synvisc-One is made from a substance called hyaluronan. It comes from chicken combs, the fleshy crests on top of the birds’ heads, according to the company. The substance is also found in the joints of the human body.
When injected into the knee, Synvisc-One is supposed to act as a lubricant and a shock absorber to relieve the pain of arthritis. Orthopedic specialists and rheumatologists typically administer the injections, which are supposed to provide up to six months of pain relief, although two specialists told the Globe that they haven’t found the product to be nearly that effective.
Each gel-filled syringe has a list price of $1,268, Koss said, but health insurance covers some of the cost for some patients.
The FDA, which was alerted by the company, is expected to post the recall online.Jonathan Saltzman
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