French regulator raises concerns about Chinese-made heparin

France's medicines regulatory authority has uncovered "critical" quality issues at a Chinese supplier of heparin.

Worryingly, the problems at the plant operated by Dongying Tiandong Pharmaceutical Co Ltd in Shandong Province, could indicate that the company may have falsified the origin of some batches of crude heparin, which is sourced from livestock.

Intentional adulteration of heparin with over-sulphated chondroitin sulphate (OSCS) - designed to dilute the active ingredient and boost profits whilst fooling quality tests - was responsible for dozens of deaths around the world among patients treated with heparin product in 2007 and 2008.

While there is no suggestion of this form of adulteration,  a report on the EU's EudraGMP database notes that polymerase chain reaction (PCR) testing results of crude heparin "showing the presence of ruminant DNA received from approved suppliers were manipulated."

"There was no evidence that the samples retested came from the same batch tested initially," it adds, noting that the traceability system deployed by Dongying Tiandong was "very weak" and the evaluation of new suppliers of crude heparin was deficient.

Quality control testing of heparin and a related low-molecular weight heparin product - enoxaparin - was woeful, with samples from approved suppliers contaminated and an unexpected additional peak in a carbon 13 nuclear magnetic resonance (NMR) test conducted by an external lab left un-investigated.

In C13 NMR testing - each peak correlates to the presence of a carbon atom within a different molecular environment - so the rogue peak could indicate a contaminant.

The deficiency report stems from an inspection in December by France's National Agency for Medicines and Health Products Safety (ANSM). As a consequence, no marketing applications can reference material produced at the facility, although for the moment there is no block on imports of heparin into Europe and the US.

The case serves as a reminder of the importance of close control of raw materials used in pharmaceutical products, another aspect of the EU's falsified medicines directive alongside pack-level measures such as unique identifiers and tamper-evidence.