Heparin safety issue raised again by US lawmakers

The vulnerabilities that led to the outbreak of heparin-related deaths in 2007 and 2008 remain in place, according to US lawmakers.

In a letter to FDA Commissioner Robert Califf, Representatives Fred Upton and Frank Pallone warn that there is every risk that an incident like the contaminated heparin scandal - which caused dozens of deaths around the world - could recur.

Moreover, "the identities of the contaminators and how the contamination was perpetrated remain unsolved after more than seven years," they write. The 2007 and 2008 deaths were attributed to economically-motivated adulteration (EMA) of heparin with over-sulfated chondroitin sulfate (OSCS) to fool identity testing.

"Loopholes and exemptions that permit part of the Chinese drug supply chain to operate without outside government scrutiny still remain," according to the representatives, who note that the FDA

Just a few weeks ago France's medicines regulatory authority warned that it had uncovered major quality issues at a Chinese supplier of heparin - including falsification of records, after an inspection last December.

Among the specific concerns raised by the politicians is that the FDA failed to share key investigative information, and did not respond effectively to "credible evidence" of contamination before the heparin crisis and for several years afterwards.

It also failed to follow up on concerns about the possible recycling of OSCS-contaminated heparin in the supply chain and overlooked prevailing market conditions in China, including an "inherent shortage in the legal pig supply in China used to make heparin."

Overall, the representatives express their concern that the lengthy and ultimately unsatisfactory investigation into the heparin scandal "suggests difficulties and challenges in enforcement against criminal economic adulteration."