The FDA is evaluating the risk of exposure to toxic chemicals from silicone tubing used in Fresenius Medical Care (NYSE: FMS) hemodialysis machines.
The investigation concerns three models of Fresenius hemodialysis machines: the 2008T, 2008K2, and 2008K.
The chemicals — non-dioxin-like (NDL) polychlorinated biphenyl acids (PCBAs) and NDL polychlorinated biphenyls (PCBs) — are in the silicone tubing used in the dialysate lines and the machine’s hydraulics.
“Although this silicone tubing does not directly contact the blood, there is the potential for back filtering through the dialyzer into the patient’s blood circulation during treatment,” the FDA said in a May 6 letter to health care providers.
The FDA said it has not received any related reports of adverse events, but said the chemicals in animals have been linked to endocrine dysfunction, hepatic effects, neurobehavioral alterations, and male reproductive effects.
Fresenius and the FDA are collecting and evaluating data to determine the risk of exposure and developing strategies to mitigate the risk, the FDA said.
“Preliminary data provided by the manufacturer to date suggest that the amount of NDL PCBAs and NDL PCBs might decrease over the first month during routine clinical use of the hemodialysis machine,” the FDA said. “However, additional testing is needed, and the manufacturer is conducting further testing and analysis to determine the degree and duration of exposure.”
The agency recommended health care providers consider alternative machines if they have new Fresenius 2008T hemodialysis machines that have been in use for less than a month. But the FDA said health care providers should not discontinue dialysis treatments and should keep using the machines if that’s their only option.
The two other models — the 2008K2 and 2008K — are no longer being made but may still be in use.
Fresenius said machine development testing to meet ISO-10993 (2020) standards showed that the chemicals could leach from silicone tubing manufactured with a peroxide-based catalyst.
“The testing was performed by multiple analytical techniques on specimens of purified water run through the machines under typical chronic outpatient treatments conditions, but without filtering through a dialyzer,” Fresenius said in a field notification. “The testing results unexpectedly identified NDL-PCBAs in high amounts that were determined to have leached from peroxide catalyst tubing in the machines’ internal hydraulic tubing.”
The company said it put a temporary distribution hold on new machines and parts with peroxide catalyst tubing on April 21, 2022, and “is working to transition from catalyst tubing in internal hydraulic systems to tubing manufactured with a platinum catalyst (‘platinum catalyst tubing’) as quickly as possible.”
Bad Homburg, Germany-based Fresenius provides dialysis treatments for about 345,000 patients through 4,171 dialysis clinics around the globe. It’s one of the largest medtech companies in the world, coming in at No. 28 on the 2021 Medtech Big 100 ranking.
The FDA recently warned of a different problem with silicon-based tubes made by Medtronic.