SEARCHING FOR SYNTHETIC HEPARIN: Rensselaer Polytechnic Institute's Robert Linhardt has been searching for a way to make heparin in the lab and decrease the drug industry's dependence on China.
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Blood thinners made from the complex carbohydrate heparin have been routinely used in the U.S. since the 1930s to keep veins, arteries and lungs clear of potentially fatal clots and to reduce the amount of time that kidney failure patients spend on dialysis machines. These drugs are so popular that there is not enough heparin—the active pharmaceutical ingredient (primarily derived from pig intestines) that enables these blood thinners to stop or prevent blood from clotting during medical procedures and treatments—to meet the daily U.S. demand of 300,000-plus doses. To make up the difference, U.S. drug makers purchase the majority of the heparin used in their products from China.
It's unlikely that many patients considered the source of the drug until earlier this year, when doctors began reporting hundreds cases of severe side effects (including dangerously low blood pressure) attributed to contaminated batches at U.S. hospitals and clinics around the country. The U.S. Food and Drug Administration (FDA) has cited 81 deaths as a result of the contamination and continues to investigate whether the tainted meds were responsible for others.
In the wake of the deaths, the FDA launched an investigation to pinpoint the source of contamination, which it traced to Changzhou SPL Company, Ltd., based in China that supplied Wisconsin-based Scientific Protein Laboratories, LLC, (SPL) with the heparin it sold to companies such as Baxter International, Inc., in Deerfield, Ill., for that company to use in its blood-thinner products.
The incident added to fear about the safety of products made in China first raised last year when the industrial poison melamine was found in pet food that sickened and killed hundreds of U.S. cats and dogs. Melamine was also later found in dairy products, including baby formula made in China, blamed for sickening thousands of infants and killing four.
The heparin contamination was particularly disturbing, because the contaminated blood thinners passed through several layers of supposed screening. When the tainted drugs were discovered, Baxter, the supplier of 50 percent of heparin in the U.S. market, recalled nearly all of its doses (purchased from SPL). The FDA, which had since December been investigating complaints related to heparin products, tapped the expertise of several groups of scientists to find the nature and the source of the contamination by March and has since been working to tighten its screening of heparin imports from China, which supplies 70 percent of the heparin used in blood thinners worldwide. (The European Union, the U.S., Canada and Brazil supply nearly all of the rest.) The agency's investigation and efforts to find more effective ways of detecting contaminants is ongoing.
In an effort to prevent future scares, scientists are trying to develop a safer, more effective synthetic form of heparin that could be made in U.S. labs, thereby negating the need for purchasing possibly contaminated ingredients from China or other countries lacking stiff safety regs. Robert Linhardt, a professor of biology, chemistry and chemical engineering at Rensselaer Polytechnic Institute in Troy, N.Y., in February received a phone call that validated his five-year quest to develop heparin in the lab. Linhardt says he listened intently as a Baxter researcher told him about a report of severe allergic reactions to heparin-based blood thinners in dialysis patients, including children. "I was then asked if I was available to help with discovering the cause of this contamination," he says. "I responded affirmatively and then asked if it were not simply a bacterial contamination in the [heparin] vial-filling process. When I was assured that this was one of the first things tested for and ruled out, I realized that this would be a very interesting investigation, and I was hooked."
The crisis begins
The Missouri Department of Health and Senior Services first notified the U.S. Centers for Disease Control and Prevention (CDC) of a potential heparin problem in early January. Alexis Elward, an internist specializing in infectious disease at Saint Louis Children's Hospital, had alerted the department that some of her pediatric dialysis patients had suffered serious allergic reactions (including angioedema, shortness of breath, nausea, vomiting, diarrhea and abdominal pain) and, in some cases, dangerously low blood pressure after they took heparin-based blood thinners (used to prevent clots when waste is being filtered from the blood of patients whose own kidneys are too damaged to perform the function).
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8 Comments
Add CommentNOT SURPRISING... when the U.S. continues to outsource vital industrial/medical processes. Yes, we "save a few bucks" on the front end with their cheap labor... then pay dearly when undetected toxins or unsafe products are disseminated in the marketplace among us.
Reply | Report Abuse | Link to thisLow molecular heparins (eg Lovenox) are preferred for their safety, ease of administration (do not require lab monitoring of clotting parameters) and the fact that over the long-term do not cause osteoporosis or a low-platelet count.
I really don't see a realistic market for completely synthetic "high molecular weight" heparin... but then again, if I were of the PORCINE persuasion, I would certainly hope for a breakthrough.
BTW, I quit eating pork (and lamb much earlier) due to the inhumane conditions of these massive, corporate hog farms... to say nothing of the incredible runoff of pollution to nearby streams. Furthermore, pigs are smarter than your pet dog.. and certainly more intelligent than a early toddler.
Cheers!
How far back does the Heparin recall go? My mom had heart surgery in August 2007, was given Heparin, never got off respirator, had hypotension, kidney failure, and died a week later.
Reply | Report Abuse | Link to thisI do not know how long the recall goes but I seen an add on T.V. about this subject. A lawyer was taking wrongful death suits. (This is why I am at this site right now). My brother-in-law is right now taking this drug and I was trying to find out as much as possible. I am sorry I do not recall the lawyer's name but I am sure if you put heparin lawsuit in any search engine I am sure you will find it. They probably could anawer your questions. I am sorry for your lose and may God be with you.
Reply | Report Abuse | Link to thisI had been given Heparin in November of 2008 because of blood clot in lower leg, was given it 3 times and had to be taken off because was causing more clots and had to have leg amputated just above knee and my whole life has changed to the point that I cannot do any of the things I use to do. Because of this it has caused many other problems in my families life. The TV adds telling about recall was on TV at the same time this was all going on, and my husband asked doctors about it and they told him not to worry about it.
Reply | Report Abuse | Link to thisIs anyone aware of birth defects in children, i.e., limb abnormalities, whose mothers took the Lovenox injections during pregnancy?
Reply | Report Abuse | Link to thisI was in the hospital for 20's days due to having a PE! They had me on HeParin for all that Time and then the Nurse hurried in my room and cut off the HeParin Machine and never tolod Me Why?! But Now I see Why?! Here it is 2 1/2 years Later and I been In And Out the Hospital Complaining about Pain, Pain, Pain And More Pain! Come to find out it did Heart and Muscle Damaged!!!!! But I Thank God I'm Still AliVe!!!! GOD IS GOOD!!!!!!!
Reply | Report Abuse | Link to thisI was in the hospital for 20's days due to having a PE! They had me on HeParin for all that Time and then the Nurse hurried in my room and cut off the HeParin Machine and never told Me Why?! But Now I see Why?! Here it is 2 1/2 years Later and I been In And Out the Hospital Complaining about Pain, Pain, Pain And More Pain! Come to find out it did Heart and Muscle Damaged!!!!! But I Thank God I'm Still AliVe!!!! GOD IS GOOD!!!!!!!
Reply | Report Abuse | Link to thisI was in the hospital for 20's days due to having a PE! They had me on HeParin for all that Time and then the Nurse hurried in my room and cut off the HeParin Machine and never tolod Me Why?! But Now I see Why?! Here it is 2 1/2 years Later and I been In And Out the Hospital Complaining about Pain, Pain, Pain And More Pain! Come to find out it did Heart and Muscle Damaged!!!!! But I Thank God I'm Still AliVe!!!! GOD IS GOOD!!!!!!!
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