Top-down and bottom-up analysis of commercial enoxaparins

Pharmacology of Heparin and Related Drugs: An Update

Heparin has been used extensively as an antithrombotic and anticoagulant for close to 100 years. This anticoagulant activity is attributed mainly to the pentasaccharide sequence, which potentiates the inhibitory action of antithrombin, a major inhibitor of the coagulation cascade. More recently it has been elucidated that heparin exhibits anti-inflammatory effect via interference of the formation of neutrophil extracellular traps and this may also contribute to heparin's antithrombotic activity. This illustrates that heparin interacts with a broad range of biomolecules, exerting both anticoagulant and nonanticoagulant actions. Since our previous review, there has been an increased interest in these nonanticoagulant effects of heparin, with the beneficial role in patients infected with SARS2-coronavirus a highly topical example. This article provides an update on our previous review with more recent developments and observations made for these novel uses of heparin and an overview of the development status of heparin-based drugs. SIGNIFICANCE STATEMENT: This state-of-the-art review covers recent developments in the use of heparin and heparin-like materials as anticoagulant, now including immunothrombosis observations, and as nonanticoagulant including a role in the treatment of SARS-coronavirus and inflammatory conditions.

State-of-the-art glycosaminoglycan characterization

Glycosaminoglycans (GAGs) are heterogeneous acidic polysaccharides involved in a range of biological functions. They have a significant influence on the regulation of cellular processes and the development of various diseases and infections. To fully understand the functional roles that GAGs play in mammalian systems, including disease processes, it is essential to understand their structural features. Despite having a linear structure and a repetitive disaccharide backbone, their structural analysis is challenging and requires elaborate preparative and analytical techniques. In particular, the extent to which GAGs are sulfated, as well as variation in sulfate position across the entire oligosaccharide or on individual monosaccharides, represents a major obstacle. Here, we summarize the current state-of-the-art methodologies used for GAG sample preparation and analysis, discussing in detail liquid chromatograpy and mass spectrometry-based approaches, including advanced ion activation methods, ion mobility separations and infrared action spectroscopy of mass-selected species.

Commercial Low Molecular Weight Heparins - Patent Ecosystem and Technology Paradigm for Quality Characterization

Heparin is a subject of ever-growing interest for laboratory researchers and pharmaceutical industry. One of the driving factors is its critical life-saving drug status, which during the COVID-19 pandemic has assumed a central role in disease treatment and/or prevention. Apart, heparin is one amongst few drugs enjoying a "demand constant" status. In 2020, heparin market size was valued to US$6.5 bn., and given the ongoing stability in the COVID-19 health crisis, it is expected to reach US$11.43 bn. by 2027 with yearly growth rate momentum (CAGR) of 3.9% during the forecast period (Pepi et al., Mol Cell Proteomics 20:100,025, 2021). As patent is a limited monopoly, every year, many patents on low molecular weight heparin (LMWH; a chemically or enzymatically degraded product of unfractionated heparin) are losing market exclusivity worldwide, inviting the generic/biosimilar drug manufacturers to capture market share with cheaper drug products. By tracking patent expiration, drugs in patent litigation, regulatory setbacks for innovator companies (such as those seeking data exclusivity or patent term extension), or other unexpected events affecting market demand and competition, generics can make investment decisions in manufacturing off-patent LMWH drug products of commercial significance. However, given the US Food and Drug Administration (FDA), European Medicine Agency (EMA), Drug Regulatory Authority of Pakistan (DRAP), and other regulatory authorities scientifically rigorous standards for generic/biosimilar LMWH drug products marketing approval, the market is secured and momentous for drug makers that could demonstrate through scientific and clinical dataset that the generic/biosimilar LMWH drug product is of the same quality and purity as the innovator drug product. This study presents an overview of the patent landscape of commercially available LMWHs and advanced analytical techniques for their structural and biochemical characterization for quality control and quality assurance during manufacturing and post-marketing. The study also covers FDA, EMA, Health Canada, and DRAP's current approaches to evaluating the generic/biosimilar LMWH drug products for quality, safety including immunogenicity, and efficacy.

Saturated tetrasaccharide profile of enoxaparin. An additional piece to the heparin biosynthesis puzzle

Enoxaparin, widely used antithrombotic drug, is a polydisperse glycosaminoglycan with highly microheterogeneous structure dictated by both parent heparin heterogeneity and depolymerization conditions. While the process-related modifications of internal and terminal sequences of enoxaparin have been extensively studied, very little is known about the authentic non-reducing ends (NRE). In the present study a multi-step isolation and thorough structural elucidation by NMR and LC/MS allowed to identify 16 saturated tetramers along with 23 unsaturated ones in the complex enoxaparin tetrasaccharide fraction. Altogether the elucidated structures represent a unique enoxaparin signature, whereas the composition of saturated tetramers provides a structural readout strictly related to the biosynthesis of parent heparin NRE. In particular, both glucuronic and iduronic acids were detected at the NRE of macromolecular heparin. The tetrasaccharides bearing glucosamine at the NRE are most likely associated with the heparanase hydrolytic action. High sulfation degree and 3-O-sulfation are characteristic for both types of NRE.

Comprehensive analysis of heparinase derived heparin-products using two-dimensional liquid chromatography coupled with mass spectrometry

Heparin is a linear sulfated polysaccharide. It is composed of a repeating disaccharide unit with different sulfo patterns. The compositional analysis after heparin was decomposed to disaccharides and enzyme resistant domains is an important way to delve into its structure. Strong anion exchange (SAX) chromatography is commonly used for the compositional analysis due to its high resolution, stability and capability of quantitation. However, nonvolatile salt in mobile phase is not compatible with MS, then the structural domains cannot be identified without standards. Here, a new two-dimensional liquid chromatography system, multiple heart cut (MHC), was developed and linked to mass spectrometry (MS) directly to provide a comprehensive analysis of enzyme digested heparin. SAX was applied as the first dimensional chromatography, in which 17 peaks were observed and integrated in the digested heparin. Size-exclusion chromatography (SEC) was used as the second dimensional chromatography to desalt efficiently. Structural information of each component was then obtained with MS, including eight common disaccharides, eight enzyme resistant tetrasaccharides and a heparin-core protein linkage domain. The comparison of enzyme digested heparins obtained from different vendors using this system suggested their similar major structure and activity, but slightly different production processes.

Recent advances in biotechnology for heparin and heparan sulfate analysis

Heparan sulfate (HS) is a class of linear, sulfated, anionic polysaccharides, called glycosaminoglycans (GAGs), which present on the mammalian cell surfaces and extracellular matrix. HS GAGs display a wide range of critical biological functions, particularly in cell signaling. HS is composed of repeating units of 1 → 4 glucosidically linked uronic acid and glucosamine residues. Heparin, a pharmacologically important version of HS, having higher sulfation and a higher content of iduronic acid than HS, is a widely used clinical anticoagulant. However, due to their heterogeneity and complex structure, HS and heparin are very challenging to analyze, limiting biological studies and even resulting in safety concerns in their therapeutic application. Therefore, reliable methods of structural analysis of HS and heparin are critically needed. In addition to the structural analysis of heparin, its concentration in blood needs to be closely monitored to avoid complications such as thrombocytopenia or hemorrhage caused by heparin overdose. This review summarizes the progress in biotechnological approaches in the structural characterization of HS and heparin over the past decade and includes the development of the ultrasensitive approaches for detection and measurement in biological samples.

Bottom-up and top-down profiling of pentosan polysulfate

Pentosan polysulfate (PPS) is a semi-synthetic glycosaminoglycan (GAG) mimetic. PPS, synthesized through the chemical sulfonation of a plant-derived β-(1 → 4)-xylan, is the active pharmaceutical ingredient of the drug Elmiron™ used to treat interstitial cystitis. Unlike natural GAGs that can be enzymatically broken down into oligosaccharides for analysis, PPS is an unnatural polyanionic polysaccharide and is not amenable to such an analytical approach. Instead reactive oxygen species were used for the controlled depolymerization of PPS and the resulting oligosaccharide fragments were then analyzed by liquid chromatography-mass spectrometry (LC-MS) to obtain bottom-up information on its composition. Because PPS has an average molecular weight ranging from 4000 to 6000 Da, similar to that of low molecular weight heparin, this suggested that it might be possible to use LC-MS on its intact chains and perform top-down analysis. The bottom-up and top-down analysis of PPS provides the first detailed compositional and structural information on PPS. Finally, we examined whether PPS would interfere with polysaccharide lyases and hydrolases, used in the analysis of natural GAGs such as chondroitin sulfates, heparan sulfate, and keratan sulfates. We found that PPS did not interfere with GAG analysis, suggesting that a combination of chemical and enzymatic treatment could be used to analyze samples containing both natural GAGs and PPS.

Biosimilars of low molecular weight heparins: Relevant background information for your drug formulary

Biosimilars of low molecular weight heparins (LMWHs) are more alike the originator than different branded LMWHs. The latter differ largely in molecular weight, anti-FXa/anti-FIIa ratio and antithrombin binding. The Food and Drug Administration and European Medicines Agency guidelines are sufficient for the clinical use of high quality LMWHs. However, the Food and Drug Administration guideline lacks the results of a phase I clinical trial in the approval process. Most information about biosimilars is available for enoxaparin given that many biosimilars of enoxaparin have received market access. The guidelines of many International Thrombosis Societies for LMWH biosimilars are too stringent, not updated and impractical for formulary uptake discussions. This review gives background information on critical factors for the formulary uptake process of LMWHs with special attention for the use of the System of Objectified Judgment Analysis/Infomatrix model.

Efficacy and Safety of a Biosimilar Versus Branded Enoxaparin in the Prevention of Venous Thromboembolism Following Major Abdominal Surgery: A Randomized, Prospective, Single-Blinded, Multicenter Clinical Trial

Several biosimilar versions of enoxaparin are already approved and in use globally. Analytical characterization can establish good quality control in manufacturing, but they may not assure similarity in clinical outcomes between biosimilar and branded enoxaparin. This study evaluated the efficacy and safety of biosimilar Cristália versus branded Sanofi enoxaparin in venous thromboembolism (VTE) prevention in patients undergoing major abdominal surgery at risk for VTE. In this randomized, prospective single-blind study, we compared Cristália enoxaparin (Ce), a biosimilar version, versus branded Sanofi enoxaparin (Se; at a dose of 40 mg subcutaneously per day postoperatively from 7 to 10 days) in 243 patients submitted to major abdominal surgery at risk for VTE for VTE prevention. The primary efficacy outcome was occurrence of VTE or death related to VTE. The principal safety outcomes were a combination of major bleeding and clinically relevant non-major bleeding. Bilateral duplex scanning of the legs was performed from days 10 to 14, and follow-ups were performed up to 60 days after surgery. The incidence of VTE was 4.9% in the Cristália group and 1.1% in the Sanofi group (absolute risk difference = 3.80%, 95% confidence interval [CI]: −1.4%-9.0%) yielding noninferiority since the 95% CI does not reach the prespecified value Δ = 20%. Clinically significant bleeding occurred in 9.9% in the Cristália group and in 5.5% in the Sanofi group (n.s. ). In conclusion, this study suggests that 40 mg once daily of Ce, a biosimilar enoxaparin, is as effective and safe as the branded Sanofi enoxaparin in the prophylaxis of VTE in patients submitted to major abdominal surgery at risk for VTE.

Analysis of sulfates on low molecular weight heparin using mass spectrometry: structural characterization of enoxaparin

INTRODUCTION

Structural characterization of low molecular weight heparin (LMWH) is critical to meet biosimilarity standards. In this context, the review focuses on structural analysis of labile sulfates attached to the side-groups of LMWH using mass spectrometry. A comprehensive review of this topic will help readers to identify key strategies for tackling the problem related to sulfate loss. At the same time, various mass spectrometry techniques are presented to facilitate compositional analysis of LMWH, mainly enoxaparin. Areas covered: This review summarizes findings on mass spectrometry application for LMWH, including modulation of sulfates, using enzymology and sample preparation approaches. Furthermore, popular open-source software packages for automated spectral data interpretation are also discussed. Successful use of LC/MS can decipher structural composition for LMWH and help evaluate their sameness or biosimilarity with the innovator molecule. Overall, the literature has been searched using PubMed by typing various search queries such as 'enoxaparin', 'mass spectrometry', 'low molecular weight heparin', 'structural characterization', etc. Expert commentary: This section highlights clinically relevant areas that need improvement to achieve satisfactory commercialization of LMWHs. It also primarily emphasizes the advancements in instrumentation related to mass spectrometry, and discusses building automated software for data interpretation and analysis.

An engineered platform based on chitin-affinity immobilization for producing low molecular weight heparin

Using chitin-affinity interaction between triple-functional heparinase I (Hep I) and chitin, an engineered platform was prepared to produce controllable low molecular weight heparin (LMWH). Chitin microspheres with well-defined nanofibrils were fabricated through a "bottom up" pathway. An enhanced soluble protein, ChBD-SUMO-Hep I (CSH-I), was expressed in 3L batch fermentation with a high bioactivity of 2.5×10³ IU/L. Chitin binding domain (ChBD) can specifically bind to chitin in noncovalent way, which leads to the immobilization and purification of enzyme in a single step. The immobilized CSH-I was preferred over its free counterpart due to its higher tolerance to heat and pH, as well as improved shelf-life. The restraint enzyme could be reused up to 8 times to achieve a conversion yield exceeding 90%. By using the bioinspired conjugates, the qualified LMWH fractions were obtained by monitoring the degradation process with an absorbance range of 44.5-68.3 at 232nm.