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The US regulatory and pharmacopeia response to the global heparin contamination crisis



The contamination of the widely used lifesaving anticoagulant drug heparin in 2007 has drawn renewed attention to the challenges that are associated with the characterization, quality control and standardization of complex biological medicines from natural sources. Heparin is a linear, highly sulfated polysaccharide consisting of alternating glucosamine and uronic acid monosaccharide residues. Heparin has been used successfully as an injectable antithrombotic medicine since the 1930s, and its isolation from animal sources (primarily porcine intestine) as well as its manufacturing processes have not changed substantially since its introduction. The 2007 heparin contamination crisis resulted in several deaths in the United States and hundreds of adverse reactions worldwide, revealing the vulnerability of a complex global supply chain to sophisticated adulteration. This Perspective discusses how the US Food and Drug Administration (FDA), the United States Pharmacopeial Convention (USP) and international stakeholders collaborated to redefine quality expectations for heparin, thus making an important natural product better controlled and less susceptible to economically motivated adulteration.

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Figure 1: Heparin crisis and resolution timeline.
Figure 2: Structures of disaccharide-repeating units of glycosaminoglycans.
Figure 3: Orthogonal analysis of heparin.


  1. Laremore, T.N., Zhang, F., Dordick, J.S., Liu, J. & Linhardt, R.J. Recent progress and applications in glycosaminoglycan and heparin research. Curr. Opin. Chem. Biol. 13, 633–640 (2009).

    CAS  Article  Google Scholar 

  2. Lindahl, U. 'Heparin'—from anticoagulant drug into the new biology. Glycoconj. J. 17, 597–605 (2000).

    CAS  Article  Google Scholar 

  3. Petitou, M., Casu, B. & Lindahl, U. 1976-1983, a critical period in the history of heparin: the discovery of the antithrombin binding site. Biochimie 85, 83–89 (2003).

    CAS  Article  Google Scholar 

  4. Barrowcliffe, T.W. History of heparin. Handb. Exp. Pharmacol. 2012, 3–22 (2012).

    Article  Google Scholar 

  5. United States Pharmacopeia. Official monographs: Heparin Sodium (US 14). (1950)

  6. Blossom, D.B. et al. Outbreak of adverse reactions associated with contaminated heparin. N. Engl. J. Med. 359, 2674–2684 (2008).

    CAS  Article  Google Scholar 

  7. Kishimoto, T.K. et al. Contaminated heparin associated with adverse clinical events and activation of the contact system. N. Engl. J. Med. 358, 2457–2467 (2008).

    CAS  Article  Google Scholar 

  8. McMahon, A.W. et al. Description of hypersensitivity adverse events following administration of heparin that was potentially contaminated with oversulfated chondroitin sulfate in early 2008. Pharmacoepidemiol. Drug Saf. 19, 921–933 (2010).

    Article  Google Scholar 

  9. Guerrini, M. et al. Oversulfated chondroitin sulfate is a contaminant in heparin associated with adverse clinical events. Nat. Biotechnol. 26, 669–675 (2008).

    CAS  Article  Google Scholar 

  10. Liu, H., Zhang, Z. & Linhardt, R.J. Lessons learned from the contamination of heparin. Nat. Prod. Rep. 26, 313–321 (2009).

    CAS  Article  Google Scholar 

  11. United States Pharmacopeia. Official monographs: Heparin Sodium (US 32–NF27) (2011).

  12. United States Pharmacopeia Official monographs: Heparin Sodium (US 34–NF29) (2009).

  13. FDA Guidance for Industry. Heparin for Drug and Medical Device Use: Monitoring Crude Heparin for Quality. (June 2013).

  14. Mulloy, B. Structure and physicochemical characterisation of heparin. Handb. Exp. Pharmacol. 2012, 77–98 (2012).

    Article  Google Scholar 

  15. Turnbull, J.E., Hopwood, J.J. & Gallagher, J.T. A strategy for rapid sequencing of heparan sulfate and heparin saccharides. Proc. Natl. Acad. Sci. USA 96, 2698–2703 (1999).

    CAS  Article  Google Scholar 

  16. Liu, J. & Linhardt, R.J. Chemoenzymatic synthesis of heparan sulfate and heparin. Nat. Prod. Rep. 31, 1676–1685 (2014).

    CAS  Article  Google Scholar 

  17. Ogren, S. & Lindahl, U. Cleavage of macromolecular heparin by an enzyme from mouse mastocytoma. J. Biol. Chem. 250, 2690–2697 (1975).

    CAS  PubMed  Google Scholar 

  18. Raman, K., Mencio, C., Desai, U.R. & Kuberan, B. Sulfation patterns determine cellular internalization of heparin-like polysaccharides. Mol. Pharm. 10, 1442–1449 (2013).

    CAS  Article  Google Scholar 

  19. Keire, D.A. et al. Characterization of currently marketed heparin products: key tests for quality assurance. Anal. Bioanal. Chem. 399, 581–591 (2011).

    CAS  Article  Google Scholar 

  20. Viskov, C. & Mourier, P. Process for oxidizing unfractionated heparins and detecting or absence of glycoserine in heparin and heparin products. US patent 0,215,519 (2005).

  21. Mourier, P.A.J., Guichard, O.Y., Herman, F. & Viskov, C. Heparin sodium compliance to USP monograph: structural elucidation of an atypical 2.18 ppm NMR signal. J. Pharm. Biomed. Anal. 67-68, 169–174 (2012).

    CAS  Article  Google Scholar 

  22. Lee, S.E. et al. NMR of heparin API: investigation of unidentified signals in the USP-specified range of 2.12-3.00 ppm. Anal. Bioanal. Chem. 399, 651–662 (2011).

    CAS  Article  Google Scholar 

  23. Guerrini, M. et al. Effects on molecular conformation and anticoagulant activities of 1,6-anhydrosugars at the reducing terminal of antithrombin-binding octasaccharides isolated from low-molecular-weight heparin enoxaparin. J. Med. Chem. 53, 8030–8040 (2010).

    CAS  Article  Google Scholar 

  24. Mazák, K., Beecher, C.N., Kraszni, M. & Larive, C.K. The interaction of enoxaparin and fondaparinux with calcium. Carbohydr. Res. 384, 13–19 (2014).

    Article  Google Scholar 

  25. Ye, H. et al. Characterization of currently marketed heparin products: key tests for LMWH quality assurance. J. Pharm. Biomed. Anal. 85, 99–107 (2013).

    CAS  Article  Google Scholar 

  26. Zhang, Z. et al. Analysis of pharmaceutical heparins and potential contaminants using (1)H-NMR and PAGE. J. Pharm. Sci. 98, 4017–4026 (2009).

    CAS  Article  Google Scholar 

  27. United States Pharmacopeia. Official monographs: Heparin Sodium (US 37–NF32) (Accessed January 8, 2014).

  28. Sommers, C.D. et al. Characterization of currently marketed heparin products: analysis of molecular weight and heparinase-I digest patterns. Anal. Bioanal. Chem. 401, 2445–2454 (2011).

    CAS  Article  Google Scholar 

  29. Neville, G.A., Mori, F., Holme, K.R. & Perlin, A.S. Monitoring the purity of pharmaceutical heparin preparations by high-field 1H-nuclear magnetic resonance spectroscopy. J. Pharm. Sci. 78, 101–104 (1989).

    CAS  Article  Google Scholar 

  30. Mulloy, B. et al. USP compendial methods for analysis of heparin: chromatographic determination of molecular weight distributions for heparin sodium. Anal. Bioanal. Chem. 406, 4815–4823 (2014).

    CAS  Article  Google Scholar 

  31. Guerrini, M. et al. Antithrombin-binding octasaccharides and role of extensions of the active pentasaccharide sequence in the specificity and strength of interaction. Evidence for very high affinity induced by an unusual glucuronic acid residue. J. Biol. Chem. 283, 26662–26675 (2008).

    CAS  Article  Google Scholar 

  32. Honchel, R. et al. A dose-response study in animals to evaluate the anticoagulant effect of the stage 2 unfractionated heparin USP monograph change. Regul. Toxicol. Pharmacol. 60, 318–322 (2011).

    CAS  Article  Google Scholar 

  33. Tami, C. et al. Inhibition of Taq polymerase as a method for screening heparin for oversulfated contaminants. Biomaterials 29, 4808–4814 (2008).

    CAS  Article  Google Scholar 

  34. Spencer, J.A. et al. Screening of heparin API by near infrared reflectance and Raman spectroscopy. J. Pharm. Sci. 98, 3540–3547 (2009).

    CAS  Article  Google Scholar 

  35. Trehy, M.L., Reepmeyer, J.C., Kolinski, R.E., Westenberger, B.J. & Buhse, L.F. Analysis of heparin sodium by SAX/HPLC for contaminants and impurities. J. Pharm. Biomed. Anal. 49, 670–673 (2009).

    CAS  Article  Google Scholar 

  36. Keire, D.A. et al. Analysis of crude heparin by 1H-NMR, capillary electrophoresis, and strong-anion-exchange-HPLC for contamination by over sulfated chondroitin sulfate. J. Pharm. Biomed. Anal. 52, 921–926 (2010).

    Article  Google Scholar 

  37. Keire, D.A., Mans, D.J., Ye, H., Kolinski, R.E. & Buhse, L.F. Assay of possible economically motivated additives or native impurities levels in heparin by 1H NMR, SAX-HPLC, and anticoagulation time approaches. J. Pharm. Biomed. Anal. 52, 656–664 (2010).

    CAS  Article  Google Scholar 

  38. Brustkern, A.M., Buhse, L.F., Nasr, M., Al-Hakim, A. & Keire, D.A. Characterization of currently marketed heparin products: reversed-phase ion-pairing liquid chromatography mass spectrometry of heparin digests. Anal. Chem. 82, 9865–9870 (2010).

    CAS  Article  Google Scholar 

  39. Zang, Q. et al. Combining (1)H NMR spectroscopy and chemometrics to identify heparin samples that may possess dermatan sulfate (DS) impurities or oversulfated chondroitin sulfate (OSCS) contaminants. J. Pharm. Biomed. Anal. 54, 1020–1029 (2011).

    CAS  Article  Google Scholar 

  40. Zang, Q. et al. Class modeling analysis of heparin 1H NMR spectral data using the soft independent modeling of class analogy and unequal class modeling techniques Anal. Chem. 83, 1030–1039 (2011).

    CAS  Article  Google Scholar 

  41. Sommers, C.D., Mans, D.J., Mecker, L.C. & Keire, D.A. Sensitive detection of oversulfated chondroitin sulfate in heparin sodium or crude heparin with a colorimetric microplate based assay. Anal. Chem. 83, 3422–3430 (2011).

    CAS  Article  Google Scholar 

  42. Zang, Q. et al. Identification of heparin samples that contain impurities or contaminants by chemometric pattern recognition analysis of proton NMR spectral data. Anal. Bioanal. Chem. 401, 939–955 (2011).

    CAS  Article  Google Scholar 

  43. Sommers, C.D. & Keire, D.A. Detection of possible economically motivated adulterants in heparin sodium and low molecular weight heparins with a colorimetric microplate based assay. Anal. Chem. 83, 7102–7108 (2011).

    CAS  Article  Google Scholar 

  44. Toby, T.K., Sommers, C.D. & Keire, D.A. Detection of native chondroitin sulfate impurities in heparin sodium with a colorimetric micro-plate based assay. Anal. Methods 4, 1488–1491 (2012).

    CAS  Article  Google Scholar 

  45. Sommers, C.D., Montpas, N., Adam, A. & Keire, D.A. Characterization of currently marketed heparin products: adverse event relevant bioassays. J. Pharm. Biomed. Anal. 67-68, 28–35 (2012).

    CAS  Article  Google Scholar 

  46. Keire, D.A., Buhse, L.F. & al-Hakim, A. Characterization of currently marketed heparin products: composition analysis by 2D-NMR. Anal. Methods 5, 2984–2994 (2013).

    CAS  Article  Google Scholar 

  47. Nemes, P., Hoover, W.J. & Keire, D.A. High-throughput differentiation of heparin from other glycosaminoglycans by pyrolysis mass spectrometry. Anal. Chem. 85, 7405–7412 (2013).

    CAS  Article  Google Scholar 

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The authors appreciate the financial and logistical support provided by USP; the contributions of USP volunteers, the scientific community, and the collaborating laboratories; the public comments; and the collaboration of the FDA, including helpful review and discussion.

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Correspondence to Ali Al-Hakim.

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A.Y.S., K.J., G.G., E.G., T.M., B.M., M.N., R.W., J.W., D.K. and A. A.-H. declare no competing financial interests. R.J.L. declares competing interest in the form of funding derived from the NIH in the form of research grants in the area of heparin analysis and regularly consults on heparin analysis. J.L. declares competing interest in the form of funding derived from the NIH and FDA in the form of research grants in the area of heparin. J.L. is a founder of Glycan Therapeutics, LLC. C.V. is an employee of Sanofi and has financial interest in the company. E.K.C. was a stockholder and employee of Baxter Healthcare Corporation during the completion of this work. W.E.W. is an employee of Pfizer and has financial interest in the company.

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Szajek, A., Chess, E., Johansen, K. et al. The US regulatory and pharmacopeia response to the global heparin contamination crisis. Nat Biotechnol 34, 625–630 (2016).

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