Swine fever that has killed millions of pigs in China and triggered a squeeze on supplies of heparin has forced one of its largest manufacturers to begin limiting allocations of the treatment.
Germany’s Fresenius Kabi said in a letter that it is limiting allocations of the drug “due to a potential shortage of raw ingredient.”
Crude heparin, which is used to produce the anticoagulant used in kidney dialysis and during open-heart surgery, is derived from pig intestines. Earlier this summer, reports pegged China’s loss of pigs due to swine fever at 150 million of an estimated 440 million swine nationwide.
“We source from multiple suppliers and geographies to server our customers, but the situation in China is expected to cause API supply constraints globally for an unknown period,” the company said in the letter released in July.
The tight supply of heparin has been exacerbated by finished product supply interruptions from other manufacturers, the company added.
RELATED: Congress hits panic button over potential Chinese heparin shortage as swine herds ravaged by disease
Some of the dose forms of heparin from Baxter Healthcare and Pfizer's Hospira are in shortage, according to an FDA database.
Earlier this summer, six U.S. congress members representing both parties called on the FDA to provide assurances that the heparin supply in America will not be threatened due to the pig die-off in China.
“Pharmaceutical researchers are raising concerns that the African swine fever outbreak in China ‘has the potential to cause an unprecedented shortage of heparin’s raw materials,’” the leader said in a letter sent to acting FDA Commissioner Norman Sharpless.
Under the regulatory agency’s rules, heparin may only be produced from pig intestines because the use of “ruminant” animals like cattle can result in contaminations such as bovine spongiform encephalopathy or oversulfated chondroitin sulfate (OSCS), which is a cheap filler that can be deadly to patients.
More than a decade ago, Chinese heparin contaminated with OSCS was linked to 80 deaths of dialysis patients in the U.S. Late last year, European regulators banned a Chinese supplier after contamination risks were uncovered.