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Biopharmaceutical benchmarks 2006 Gary Walsh The rate of biopharmaceutical approvals has leveled off, but some milestones bode well for the future.

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he past three years have been interesting times for the biopharmaceutical industry. The first biosimilar product—Omnitrope (recombinant human growth hormone (rhGH); Sandoz, Holzkirchen, Germany) for treating growth hormone deficiencies—was approved in both the United States and Europe; the European Medicines Agency (EMEA) has recommended approval of a protein drug produced in a transgenic organism; advances were made in drug delivery, culminating in the approval of the first products delivered via nonparenteral means—Exubera, Nektar Therapeutics’ (San Carlos, California, USA) inhalable recombinant insulin and Fortical, Unigene Laboratories’ (Fairfield, New Jersey, USA) recombinant calcitonin nasal spray; and the first nucleic acid aptamer, Macugen (pegaptanib; Eyetech Pharmaceuticals, New York) was approved for treating macular degeneration in 2004. But there were also some disappointments; overall progress in gene therapy as well as other nucleic acid–based medicines has been slow, and adverse effects of two monoclonal antibodies (mAbs)—Biogen Idec’s (Cambridge, Massachusetts, USA) Tysabri (natalizumab), which was approved for treating multiple sclerosis (MS), and TeGenero’s (Wurzburg, Germany) immunomodulator TGN1412, which was in phase-1 clinical trials—bring into sharp focus some potential downsides of biopharmaceutical therapy. Overall, some 165 biopharmaceutical products (recombinant proteins, monoclonal antibodies and nucleic acid–based drugs) have now gained approval (Table 1), with a market size estimated at some $33 billion in 2004 (ref. 1) and projected to reach $70 billion by the end Gary Walsh is in the Industrial Biochemistry Programme, University of Limerick, Limerick, Ireland. e-mail: [email protected].

18

2003–2006

16

16

2000–2003

14 12

11 8

8 6

5

4

6 4

6 3

2 0

1982–2000

10

10

Cancer

Diabetes

4

4

2 Growth disturbances

3 1

Hemophilia

0 Hepatitis

Figure 1 Number of approved biopharmaceuticals in five major markets.

of the decade2,3. In this context, erythropoietin (EPO) still leads the field—combined sales of all recombinant EPOs for 2005 reached $10.7 billion. Future prospects therefore look strong, underpinned by continued significant R&D spending and several hundred biopharmaceuticals currently in clinical trials. This article provides an update on biopharmaceuticals approved during the past three and a half years (from January 2003 to June 2006), examining which types of biopharmaceuticals have been launched and for what indications. Not included in the survey are those tissueengineering products that the US Food and Drug Administration (FDA) classifies as pure medical devices. New arrivals Over the past three and a half years, regulators in North America and Europe approved a total of 32 biopharmaceuticals for human use. The approved drugs include recombinant hormones and growth factors, mAb-based products and therapeutic enzymes, as well as one recombinant blood factor, two recombinant vaccines and a nucleic acid–based product. Five of the products approved for the first time in one region had previously been approved in a different region before 2003.

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Therefore, the period witnessed the approval of 27 genuinely new biopharmaceuticals. (For comparison, in our last accounting, 30 novel biopharmaceuticals had been approved in the three-year period assessed4.) Looking at each region independently during this period, an estimated total of 100 new medical entities (NMEs) and biologic license applications (BLAs) were approved in the United States, of which 24 (24%) were biopharmaceuticals. Within Europe, some 86 NMEs were approved, of which 19 (22%) were biopharmaceuticals. Again, these average values are slightly lower than that reported in our last survey, where closer to 25% of all genuinely new drugs approved (from 2000 to mid 2003) were biopharmaceuticals4. Approval trends Comparing product approvals since 2003 to those in the previous three years reveals some interesting trends (Fig. 1). Although the products approved represent very significant product categories, no interferon, interleukin, thrombolytic or anticoagulant-based biopharmaceutical was approved over the past three years, and only two recombinant vaccines and one recombinant blood factor came on the market. Hence, proportionately larger

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F E AT U R E numbers of growth factors, mAb-based products and enzymes were approved in this latest three-year period. These trends more likely reflect commercial rather than technical considerations; new interferons, thrombolytics or blood factors, for example, would face stiff competition from the numerous such products already on the market. Although blockbusters are well represented on the market, interestingly, at least five of the new approvals have designated orphan status. A parallel shift in the profile of target indications is also evident. Our previous report found hepatitis to be the most frequently targeted indication, with eight interferon-based and eight prophylactic vaccines approved for its treatment. In marked contrast, no product aimed at this indication entered the marketplace over the past three years. Cancer, predictably, remains a prominent indication (four product approvals), while abnormal growth–related conditions (four products) and the treatment of rare genetic defects (Pompe disease and mucopolysaccharidosis; three products) were also among the more frequent target indications. Another trend gathering pace over the past three years relates to the proportion of approved drugs that have been re-engineered in some way. Of the 32 new products, 12 (38%) have been re-engineered to have either an altered amino acid sequence or post-translational modification (Table 2). Novo Nordisk’s (Princeton, NJ) long-acting insulin analog Levemir exemplifies a particularly novel engineering approach. The primary engineering strategy entailed the covalent attachment of myristic acid (a 14-carbon saturated fatty acid), which prolongs the duration of action to up to 24 h. Human serum albumin harbors three high-affinity fatty acid–binding sites and as a result binds the insulin analog tightly. The overall effect ensures a constant and prolonged release of free insulin molecules. Insulin in many ways remains the prototypic biopharmaceutical. It was the first recombinant protein ever approved (in 1982). It was one of the first biopharmaceuticals to be engineered, and over the past decade, seven fast- and long-acting engineered analogs have been approved. It has now also become the first biopharmaceutical approved for delivery by the pulmonary route, as discussed later. The increasing incidence of diabetes continues to increase the relative prominence of this biopharmaceutical. The World Health Organization (WHO; Geneva, Switzerland) estimate that some 170 million people suffer from diabetes (types 1 and 2) globally, a figure projected to double in the next 25 years (ref. 5). Although only a minority require

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insulin treatment, annual demand by 2000 in the industrialized world alone was estimated at 4,600 kg (ref. 6) and combined global sales of insulin-based products are expected to reach some $7.9 billion by 2007 (ref. 7). Nonparenteral delivery Until very recently, all biopharmaceuticals required to enter systemic circulation to bring about their therapeutic effect were administered parenterally. Parenteral administration, particularly with drugs administered on an ongoing basis, has a number of disadvantages. These include reduced patient compliance, potential complications for use in a nonclinical setting and potential safety issues in poorer world regions if needles are reused. Successful administration of labile, large and hydrophilic biopharmaceuticals via nonparenteral means represents a considerable technical challenge, as they face a myriad of hurdles including physical, chemical and enzymatic barriers to entering the bloodstream (for example, biological membranes, stomach acid, proteases or nucleases). Despite such challenges, development of oral, nasal, pulmonary, transmucosal and transdermal based biopharmaceutical delivery systems remains an active area of research8–11. The approvals of two products administered by nonparenteral means in the last two years represent notable milestones in drug delivery. Fortical, which is administered as a nasal spray, is adsorbed rapidly from the nasal mucosa. Nasal delivery is attractive because of its convenience and accessibility, the high density of blood vessels servicing the nasal cavities and the large surface area for absorption generated by the nasal microvilli. However, compared with intramuscular administration, nasal delivery results in low bioavailability (averaging 3%, with a range of 0.3–30% reported for Fortical12). In addition, nasal administration can induce nasal and related adverse effects in some patients. Low bioavailability is often a characteristic of nasal delivery, as a result of ciliary clearance of drug deposited on the mucosal blanket, the presence of proteases and inefficient uptake of larger molecules. Low-molecular-weight peptides, such as oxytocin, desmopressin and luteinizing hormone–releasing hormone analogs, cross relatively easily, facilitating their routine nasal delivery. Larger polypeptides (with molecular weights greater than approximately 10 kDa), however, do not cross the epithelial barrier without concurrent administration of detergent-like uptake enhancers, which have damaging cellular effects. Although this is not an issue for the 3.5-kDa Fortical, it places constraints upon the general applicability of the approach for most therapeutic proteins.

The approval of Exubera marks a watershed for the much-touted pulmonary-based biopharmaceutical delivery. Adsorption of macromolecules (up to several hundred kilodaltons in mass) from the deep lung is surprisingly efficient, with bioavailabilities ranging from a few percent to almost 50% (ref. 13). High pulmonary bioavailability is likely to stem from the lung’s large surface area and thin diffusional layer, as well as the relatively low rate of cell surface clearance and the presence of proteolytic inhibitors. Pharmacokinetic studies found that Exubera is absorbed as quickly as subcutaneously administered rapid-acting insulin analogs14. However, clinical trials did show a greater decline in pulmonary function in the Exubera treatment group within a few months of treatment, leading to an admonition for smokers or patients with underlying lung disease. Exubera’s approval is likely to be followed by those of several other inhalable insulin products, currently in advanced development by Alkermes (Cambridge, MA, USA; in conjunction with Eli Lilly), Novo Nordisk and MannKind (Valencia, CA, USA). Moreover, the ability of proteins with molecular weights well in excess of 100 kDa to cross from the lung into the blood renders pulmonary delivery potentially applicable to many additional biopharmaceuticals. Production lines Escherichia coli and mammalian cell lines are still the workhorses of biopharmaceutical production. Nine of the 31 therapeutic proteins approved since 2003 are produced in E. coli, whereas 17 are produced by mammalian cell lines. Mammalian cell culture is technically complex, slow and expensive, yet these cell lines thus far command an effective monopoly in terms of producing large therapeutic proteins that require post-translational modification, in particular glycosylation. O-linked glycosylation (sugar side chains attached via serine or threonine residues), but most especially N-linked glycosylation (sugar side chains attached via asparagine residues) can influence protein stability, ligand binding, immunogenicity and serum half-life, and is significant in the context of efficacy (and sometimes safety) of a wide range of biopharmaceuticals including antibodies, blood factors and some hormones and cytokines. Alternative production systems capable of carrying out glycosylation include yeast, insect and plant cells. Compared with mammalian cell lines, these cells typically grow to higher cell densities in shorter fermentation cycles and in less expensive and more chemically defined media, and have a lower risk of

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F E AT U R E transmitting mammalian pathogens. Despite such technical and economic advantages, a glycosylated biopharmaceutical produced using such alternative means has yet to gain approval for human use, mainly because the exact glycosylation patterns characteristic of human proteins are not adequately reproduced by these systems and this may have functional and safety implications15. Significant progress has been reported in ‘humanizing’ the glycosylation profile characteristic of proteins made in these alternative production systems15–19. Because glycosylation is a multienzyme-based mechanism, the engineering process pursued generally entails elimination of nonhuman glycosylation reactions, concurrent introduction of characteristic human ones or both. The recently reported production of a human IgG showing a humanized N-glycan structure in glycoengineered yeast (a strain of Pichia pastoris) typifies advances in this context20. Antibody glycosylation influences the antibodies’ ability to interact with various immune effector cells, triggering antibody-dependent cell cytotoxicity (ADCC), important for effective therapeutic functioning. Unlike antibody produced in wild-type, unengineered P. pastoris, those produced in the glycoengineered yeast had functional antibody-mediated effector functions. Glycoengineered yeast in many ways represents a particularly attractive alternative to mammalian cells for producing therapeutic glycoproteins. Yeasts have been long used for the production of both recombinant and native industrial enzymes; upstream processing spans hours to days, rather than days to weeks; and severalfold higher expression levels have been reported—up to 15 g per liter (ref. 21). Additionally, engineered yeast strains have been developed that perform essentially uniform glycosylation, facilitating improved batch-to-batch product consistency 15 . Mammalian cell–derived glycoproteins are generally subject to heterogeneity of the glycans, which vary in exact detail of glycosylation, and glycocomponent profile can be influenced by such things as cell culture conditions. Variability can be problematic if different product glycoforms have differential therapeutic properties, as is the case for tissue plasminogen activator (tPA), EPO, mAbs and some hormones and cytokines. Rendering this issue more complex is the fact that, in general, it is not possible to precisely predict the functional consequences of altering glycosylation profiles. This is an active and vital ongoing area of research. Despite the promise of these alternative production systems, animal cells will continue

to represent the major production vehicle for glycosylated therapeutic proteins for the foreseeable future. Moreover, advances continue that underpin more efficient mammalian cell culture technology22. A combination of improved expression constructs and increased understanding of animal cell metabolism and physiology has resulted in continuous improvements in product yield. Recombinant protein levels approaching 5 g per liter are now possible, tenfold higher than what they were some years ago. Also of note is the successful development of serum-free and animal component–free media for several cell lines22. Ongoing research avenues include exploring approaches based both on medium manipulation and genetic engineering to prevent or retard apoptosis (to prolong protein production) and the manipulation of process parameters to minimize glycosylation heterogeneity22. Transgenic-based production After more than a decade of development, biopharmaceutical systems based on transgenic organisms remain largely just that: in development. GTC Biotherapeutics (Framingham, MA) retains a small number of products produced in the milk of transgenic animals in clinical trials. The sector received a setback in February 2006 when the Committee for Medicinal Products for Human Use (CHMP) of the EMEA issued a negative opinion relating to the marketing authorization application for GTC’s lead product ATryn (recombinant human antithrombin produced in the milk of transgenic goats) for the treatment of hereditary antithrombin deficiency. CHMP concerns were threefold: data from too few patients was presented in the application, immunogenicity studies were insufficient, and the manufacturing procedures used for trial material and product to be marketed differed, specifically a filtration step23. GTC successfully appealed the decision, however, and the EMEA issued a revised and final positive decision for ATryn last month. This increases substantially the likelihood of product approval by the European Commission (EC; Brussels, Belgium). Phase 3 trials of the product continue in the United States, with a view to subsequent BLA submission to the FDA. Although details are as yet unpublished, the EMEA’s concerns relating to potential product immunogenicity in particular have obviously been allayed. Glycosylation patterns characteristic of proteins produced in transgenic milk of higher mammals differ somewhat from those of native human proteins. The presence of N-glycolylneuraminic acid, for example, could potentially trigger

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immunological and other complications in man. Pharmacokinetic properties of ATryn in humans differ significantly from properties characteristic of traditional antithrombin preparations extracted directly from bovine blood in that the recombinant product has an almost tenfold lower plasma half-life. The ATryn saga places even greater importance on the fate of Pharming’s lead product, recombinant human C1 inhibitor (rhC1INH) made in transgenic rabbits, which is currently in phase 3 clinical trials for the treatment of hereditary angioedema. The approval of Genzyme’s (Cambridge, MA) recombinant human acid α-glucosidase (Myozyme) for treating Pompe disease this year provides another interesting case study in the context of transgenic-based systems. Genzyme originally entered into partnership with Pharming to develop this product in the milk of transgenic rabbits. However, they subsequently switched to a production system based on Chinese hamster ovary (CHO) cells (in which the commercialized product is now actually produced) because of concerns over product scalability and supply issues. Targeted expression of therapeutic proteins in the egg white of transgenic chickens is an alternative technology, in which important advances have recently been reported24. Egg white typically contains 4 g protein, of which half is derived from the ovalbumin gene. Using a (yet to be optimized) ovalbumin promoter– based expression system, it is theorized that a single hen could produced as much as 300 g of recombinant product annually, in a naturally sterile environment. Moreover, the traditional use of eggs in vaccine production would render regulatory and some manufacturing issues relatively straightforward. In pilot studies of the egg system, initial expression levels of recombinant proteins recorded were in the microgram per egg range; more recently, however, fully assembled, functional mAbs have been produced at levels of 3 mg per egg25. When compared with the same antibody produced in a CHO cell line, some differences in glycosylation detail were apparent, but antigen binding affinity was the same and ADCC was enhanced. Even so, the half-life of the mAb in mouse serum was half that of naturally obtained antibodies (reduced from ~200 to 100 h) and antigenicity remains to be comprehensively assessed. Thus, the jury remains out on egg-based production systems, pending further technical advances and detailed product characterization. Perhaps unsurprisingly, some additional transgenic approaches, such as seminal vesicle–based transgenic expression systems in which the product is excreted in the semen

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Box 1 The first biogeneric Omnitrope is a 22.1-kDa, 191-amino-acid single-chain polypeptide identical in sequence to that of native human growth hormone (hGH; Fig. 3). It is produced in E. coli by recombinant means and is indicated for treatment of growth disturbance in individuals over three years of age. Approval of a biosimilar product within the European Union requires its comparison to a medicine already approved (the reference medicine), in this case Pfizer’s Genotropin. Genotropin is also a recombinant hGH produced in E. coli and first came on the market in Europe in 1988. European regulators were satisfied Figure 3 Three-dimensional structure that Omnitrope matched Genotropin in terms of human growth hormone. (Source: of quality, safety and efficacy. Authorization The Research Collaboratory for required submission of a full quality module as Structural Bioinformatics Protein Data well as reduced clinical and nonclinical datasets. Bank (http://www.rcsb.org/pdb), ID Extensive characterization studies supported number 1 HGU.) comparability to Genotropin in terms of product identity, structure (primary, secondary and tertiary) and bioactivity and impurity levels. Omnitrope also has the same qualitative and quantitative composition in terms of active substance and the same dosage form. In terms of clinical efficacy, a nine-month study comparing Omnitrope and Genotropin in 89 hGH-deficient children was submitted. Endpoints (increases in height and speed of growth) as well as side effects reported were similar. GW

have not been pursued in the context of therapeutic protein production26. Despite early enthusiasm, considerable technical barriers remain to be overcome before injectable proteins, particularly glycoproteins, produced in transgenic plants are likely to gain regulatory approval for human use. Although advantages in scalability and cost are well documented, structural differences between plant and mammalian N-linked glycans represent a formidable hurdle, particularly as some plant-derived sugar motifs are highly immunogenic in man16. Initial engineering strategies to humanize plant-based glycosylation profiles provide encouraging results17, but such attempts are simply not sufficiently advanced to support an acceptable glycosylation pattern on biopharmaceuticals destined for human parenteral use. Immunological concerns would be greatly diminished with products for oral or topical use; this likely explains why leading products produced in plant-based systems are destined for administration in this way. Two leading plant-produced products are in phase 2 clinical trials: CaroRX (Planet Biotechnology, Hayward, CA) and Merispase (Meristem Therapeutics, Clermont-Ferrand, France). CaroRX is a hybrid mAb comprising the Cγ1 and Cγ2 domains of the heavy chain of an IgG that binds streptococcal antigen I/II—a major cell surface glycoprotein of Streptococcus

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mutans—fused to two IgA constant (C)-region α domains (Cα2 and Cα3), dimerized with an immunoglobulin joining (J) chain and a secretory component. By binding S. mutans, a major causative agent of bacterial tooth decay, it prevents the bacteria from adhering to tooth enamel. Planet Biotechnology estimates that bacterial tooth decay underpins dental expenditure of $50 billion annually in the United States alone. Merispase is a recombinant mammalian gastric lipase produced in transgenic corn. It is aimed at countering lipid malabsorption related to exocrine pancreatic insufficiency caused by cystic fibrosis and chronic pancreatitis, and is destined for oral administration. A notable milestone in this sector was observed earlier this year with the approval of DowAgroScience’s (Indianapolis, IN) subunit vaccine to prevent Newcastle disease in poultry. The veterinary vaccine is produced in plant cells rather than whole plants, an approach adopted to allay containment and environmental concerns associated with plants grown in the field. The company obtained a license for strategic purposes—to demonstrate that a safe and effective product could be produced by such means. They do not intend to actually commercialize the product. Nonetheless, the approval provides encouragement to those developing putative plant-based vaccines for both veterinary and human use.

Biosimilars Over the past three years, follow-on biologics have been (and are likely to remain) a major talking point. By 2009, ~$10 billion worth of biopharmaceuticals will have lost patent protection27. Some analysts have suggested that up to 75 currently approved therapeutic proteins will eventually become targets for biosimilar production28. The approval of Omnitrope in Australia in 2005, and subsequently in Europe and the United States in 2006 represents a fundamental milestone in this area (Box 1). Its approval was, however, not without some controversy. The EMEA originally recommended Omnitrope’s approval in June 2003 but the EC— the European body holding legal responsibility to actually grant marketing authorizations— uncharacteristically overrode the EMEA’s recommendation, rejecting the application on the basis of filing irregularities. Meanwhile, the EC and the EMEA were proactive in drafting and implementing pharmaceutical legislation to include provision for biosimilars, which came online in 2004. The EMEA also clarified biosimilar legislation with the publication of various biosimilar guidance documents in 2005 and 2006 (12 adopted guidelines, available at http://www.emea.eu.int). European requirements include a measure of clinical testing for all applications, but the extent of investigations required depends on the level of complexity of the biopharmaceutical. Regulatory requirements for prospective biosimilars within the United States remain unclear. Sandoz won a lawsuit that it filed against the FDA last September over the regulators’ inability to deliver a final decision with regard to Omnitrope29, which ultimately led to its approval last month. Yet the regulators’ stance on biogenerics remains cloudy, as Omnitrope was approved under a section of the Food, Drug and Cosmetic Act, not according to the path for more complex biologics. These actions, along with the progress made in Europe, continue to intensify the pressure upon US legislators and regulators, a pressure likely to increase as further biosimilars come on stream. European regulators underlined their acceptance of the principle of biosimilarity by approving a second such product (Valtropin, rhGH; Biopartners, Baar, Switzerland) in April, and at least two further biosimilar marketing authorization applications are currently under review by the EMEA. Nucleic acid–based therapeutics The potential of nucleic acid–based biopharmaceuticals continues to drive intensive basic and clinical research in this area. Despite some 15 years of research, only two nucleic

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Box 2 The rise of the aptamer Aptamers, sometimes referred to as decoys, are single-stranded DNA or RNA molecules that adopt a unique three-dimensional structure, allowing them to bind a specific target molecule with high affinity and specificity45,46. The technology was first developed in the early 1990s and entails the initial generation of a large aptamer library, with subsequent identification of individual aptamers binding a target ligand via an appropriate selection strategy. For DNA aptamers, the library is usually generated through chemical synthesis and amplified by PCR. RNA libraries are usually generated by in vitro transcription. Target identification is most easily undertaken by an automated in vitro selection approach known as SELEX (systematic evolution of ligands by exponential enrichment). Aptamers may prove useful for affinity-based purification, target validation, and drug discovery, diagnostics and therapeutics. Macugen is the first such product to gain regulatory approval for

acid–based products have gained approval in the United States, the EU or both—Isis Pharmaceuticals’ (Carlsbad, CA) Vitravene for cytomegalovirus infection of the eye, and Eyetech’s Macugen. China has approved one further one—Shenzhen Gentech SiBiono’s Gendicine (adenoviral serotype 5–mediated delivery of a human P53 gene) was approved for head and neck cancer in October 2003. Fundamental difficulties remain associated with product delivery, stability, immunogenicity and, for gene therapy–based medicines in particular, integration and regulation of expression. Since 1989 some 1,140 gene therapy clinical trials have been initiated, but only one such product has yet been approved globally, and none have been approved in Europe or the United States. The past three years have, however, witnessed two notable milestones in this area: Gendicine is the first gene therapy to be commercialized and approved anywhere, and Macugen is the first aptamer approved, in the US in 2004 and subsequently in Europe this year. Gendicine gained approval for use in the treatment of head and neck squamous-cell carcinoma from China’s State Food and Drug Administration (SFDA) in November 2003. The product is a replication-incompetent human serotype-5 adenovirus engineered to contain the human wild-type TP53 tumor-suppressor gene30. Direct intratumoral injection is believed to trigger vector uptake and expression of P53, leading to cell cycle arrest and apoptosis31. Company data showed complete regression of tumors in 64% of patients treated with Gendicine in combination with radiation therapy, with few associated side effects30. The product is believed to have been administered to some 50,000 patients and is in late-stage clinical trials for various other cancers32. Others are adopting a

therapeutic use (see main text). A small number of additional aptamers are in clinical trials, the most advanced of which seems to be E2F decoy (Corgentech, San Francisco, CA), currently in phase 3 trials for the prevention of bypass graft failure. The putative biopharmaceutical is a 14-nucleotide DNA-based aptamer that specifically binds (thereby inactivating) the cell cycle transcription factor E2F. E2F orchestrates vascular cell growth and multiplication, and its inactivation seems to prevent inappropriate vascular cell growth that often underpins graft blockage. Aptamer delivery relies upon pressure-based in vitro treatment of the graft before insertion into the patient. Aptamers seem to have only low immunogenicity. To retard or prevent nuclease-mediated degradation, aptamers are also usually chemically modified. In addition, they are conjugated to substances such as polyethylene glycol to prevent size-mediated renal clearance. GW

broadly similar approach to that of Gendicine, including Introgen Therapeutics (Austin, TX), whose TP53 adenoviral-based drug Advexin has entered phase 3 clinical trials in the United States for squamous-cell carcinoma. Differences in the benchmarks by which the different national drug agencies measure therapeutic efficacy and safety are likely to have an important role in determining the regulatory outcome. The United States, for example, will evaluate Advexin on its effect on five-year survival; in contrast, China’s regulators approved Gendicine on the basis of the rate by which it caused tumors to shrink in patients over a much shorter period (avoiding potential problems with immunogenicity to the virus). Similarly, unlike in the ongoing US trial, in which the gene therapy is given with and without chemotherapy, patients in the China trial were given Gendecine with radiotherapy, the therapeutic effectiveness of which is potentiated by the P53 protein. Macugen, the first aptamer (Box 2) product approved for general medical use, is an RNA oligonucleotide that binds to extracellular vascular endothelial growth factor (VEGF), thereby preventing receptor binding and signal transduction. VEGF drives vascularization (angiogenesis), underlining the product’s ability to treat neovascular macular degeneration, a condition characterized by abnormal proliferation of blood vessels in the eye, which leads to vision loss. The product, which is administered by direct intravitreous injection, also contains two covalently bound 20-kDa polyethylene glycol molecules at one end, which increase its half-life in the vitreous humor. Ribozymes and, in particular, RNA interference (RNAi)-based antisense mechanisms hold considerable promise, but are quite

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some distance from entering the arsenal of approved biopharmaceutical products33–38. Zimmermann and colleagues recently reported a notable milestone in the context of RNAi39, showing that short interfering RNA delivered systemically in a liposome formulation silenced hepatic expression of apolipoprotein B in monkeys. Postapproval adverse events Like all drugs, biopharmaceuticals have adverse as well as beneficial effects. Such negative effects are generally unearthed by clinical trials and thus taken into account by regulatory authorities when considering risk/benefit ratio. On occasion, however, serious additional difficulties only come to light postmarketing. Headline examples within the past three years include Tysabri and the continuing Eprex affair. Tysabri first came on the market in November 2004. It received accelerated FDA approval on the basis of the substantial therapeutic benefit to MS sufferers revealed by initial trials. At that time, the most serious adverse events noted were infections and temporary hypersensitivity reactions, and approval was contingent upon continuing the trials for an additional year. Marketing and ongoing trials were halted, however, in February 2005 when studies revealed one fatal and one additional case of progressive multifocal leukoencephalopathy (PML) in patients receiving Tysabri in conjunction with Avonex (interferon-β) for two years. Tysabri, however, is making a comeback. Trials recommenced earlier this year, and both the EMEA and FDA have recommended that Tysabri be approved as a single therapy for aggressive forms of MS. Johnson and Johnson’s (New Brunswick, NJ) EPO product Eprex initially became a focus of attention in the late 1990s when

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F E AT U R E an upsurge of antibody-mediated pure redcell aplasia (PRCA) was associated with its subcutaneous administration. The upsurge coincided with a formulation change in which glycine and polysorbate 80 replace human serum albumin. Subsequent studies provided evidence that a proportion of the EPO molecules were associated with polysorbate 80 micelles. The presence of multiple EPO epitopes exposed on a micellar surface could increase immunogenicity of the product40. However, others have suggested that the underlying cause was the leaching of weakly adjuvant compounds from the uncoated rubber stoppers formerly used in prefilled syringes41,42. As the debate continues, the

incidence of PRCA associated with product administration has decreased significantly over the past three years, most probably as a result of a switch from subcutaneous to intravenous administration in patients receiving ongoing therapy43. Nucleic acid–based biopharmaceuticals, too, can harbor unwelcome surprises. The FDA posted a safety alert for Macugen in April this year after rare anaphylactoid reactions were reported, necessitating changes to the product’s approved labeling. Future prospects Annual biopharmaceutical R&D expenditure has stood at $19–$20 billion over the past three

or four years and biotech-based products are increasingly dominating the pipeline1. An estimated 2,500 biotech drugs are in the discovery phase, 900 in preclinical trials and over 1,600 in clinical trials (Fig. 2). Overall, this represents 44% of all drugs in the development phase and 27% of all drugs in both preclinical and clinical trials1. Cancer remains the most common target indication for biopharmaceuticals in development, whereas mAbs and vaccines represent the most significant categories by product number. Annual sales of approved biopharmaceuticals in were estimated at $33 billion1. Sales values of therapeutic mAbs are expected to reach $16.7 billion by 2008 (ref. 2), and

Box 3 Biopharmaceuticals as antagonists Many traditional pharmaceuticals bring about their therapeutic effect by binding to and thereby inhibiting the activity of a target biomolecule, such as an enzyme or receptor. Several biopharmaceuticals are now approved that function in this way (Table 3). The exact mechanism used to achieve this varies with the products, which include selected antibodies, ligand-binding fusion products, aptamers and antisense-based molecules. Eventually these may be joined by RNAi, ribozymes and artificial non-antibody binding proteins. Attention is increasingly being focused on this last group47,48. Discovering non–antibody antagonists broadly entails taking a peptide or polypeptide sequence of known affinity for a target ligand and inserting it into a framework (scaffold) protein to

generate a novel binding protein. Scaffold proteins are relatively small, human, single-polypeptide, stable proteins or protein domains that retain their desirable physicochemical properties after insertion of the new binding domains. Libraries of such proteins can be generated and screened for the presence of a binding protein with the desired specificity. Advantages touted for such artificial binding proteins include stability and uncomplicated production in E. coli or similar expression systems, without the need for post-translational modifications (compare this to costly mammalian-based production of complex antibodies). Therapeutically, they may also suffer from disadvantages and problems, such as immunogenicity, low serum half-life, and inability to activate immune functions, such as ADCC.

Table 3 Approved biopharmaceuticals that work by binding and inactivating their targets. Product

Company

Indication and mode of action

Macugen (pegaptanib sodium injection, a synthetic PEGylated oligonucleotide)

Eyetech and Pfizer

Treatment of neovascular, age-related macular degeneration. Functions by specifically binding VEGF, thereby inhibiting the latter from binding to its cell surface receptor and triggering angiogenesis

2006 (EU) 2004 (US)

Avastin (bevacizumab, a humanized antibody)

Genentech (US) Roche (EU)

Carcinoma of the colon or rectum. Functions by specifically binding VEGF, thereby inhibiting the latter from binding to its cell surface receptor and triggering angiogenesis

2005 EU) 2004 (US)

Erbitux (cetuximab, a chimeric antibody)

ImClone Systems and Treatment of EGF receptor–expressing metastatic colorectal Bristol-Myers Squibb (US) cancer. Functions by binding to the EGF receptor, preventing Merck (EU) binding of native EGF and thereby blocking EGF receptor activation

Raptiva (efalizumab; humanized antibody)

Genentech (US) Serono (EU)

Treatment of adult patients with chronic moderate to severe plaque psoriasis. Functions by binding to LFA-1, preventing the latter from interacting with ICAMs 1, 2 and 3, a process important in development of psoriasis plaques

2004 (EU) 2003 (US)

Amevive (alefacept, a fusion protein consisting of the extracellular human leukocyte functional antigen 3 domain linked to an IgG fragment)

Biogen Idec

Chronic plaque psoriasis. Functions by binding to CD2 surface antigen found primarily on T lymphocytes, thereby blocking CD2 interaction with other immune elements

2003 (US)

Xolair (omalizumab, humanized antibody)

Genentech

Treatment of adults and adolescents with moderate to severe persistent asthma. Functions by binding to IgE, preventing IgE-triggered release of mediators of the allergic response

2003 (US)

Humira (also sold as Trudexa in EU) (adalimumab, a human monoclonal antibody)

Cambridge Antibody Technology & Abbott (US) Abbott (EU)

Treatment of rheumatoid arthritis. Functions by binding TNF-α, thereby preventing the latter form binding its cell surface receptor and triggering a proinflammatory response

2003 (EU) 2002 (US)

774

Approved

2004 (US & EU)

VOLUME 24 NUMBER 7 JULY 2006 NATURE BIOTECHNOLOGY

F E AT U R E Box 3 (continued)

Company

Indication and mode of action

Somavert (pegvisomant, an engineered hGH analog)

Pharmacia SA

Treatment of selected patients suffering from acromegaly. Functions by binding to the hGH cell surface receptor without triggering signal transduction and in the process blocking receptor activation by endogenous hGH

2003 (US) 2002 (EU)

Kineret (anakinra, an IL-1 receptor antagonist)

Amgen

Treatment of rheumatoid arthritis. Functions by binding to the IL-1 receptor without triggering signal transduction but blocking receptor activation by endogenous IL-1

2001 (US)

Enbrel (etanercept, a fusion protein)

Immunex (US) Wyeth Europa (EU)

Treatment of rheumatoid arthritis. Functions by competing with the endogenous TNF receptor for binding of TNF.

2000 (EU) 1998 (US)

Remicade (Infliximab, a chimeric antibody)

Centocor

Treatment of Crohn disease. Functions by binding TNF-α, thereby preventing the latter from binding to its receptor and triggering a proinflammatory response

1999 (EU) 1998 (US)

Zenapax (dacilzumab, a humanized antibody)

Roche

Prevention of acute organ rejection. Functions by binding to the IL-2 receptor on the surface of activated T lymphocytes, blocking the binding of IL-2 and hence preventing the stimulation of these cells, involved in organ rejection

1999 (EU) 1997 (US)

Simulect (basiliximab, a chimeric antibody)

Novartis

Prevention of organ rejection. Mode of action similar to that of Zenapax

Vitravene (Fomivirsen, an antisense oligonucleotide)

ISIS Pharmaceuticals

Treatment of cytomegalovirus (CMV) retinitis in AIDS patients. Functions by binding to a specific viral mRNA transcript, thereby preventing viral protein synthesis

ReoPro (Abciximab, antibody antigen-binding fragments)

Centocor

Prevention of blood clots. Functions by binding to integrin αIIbβ3 (the glycoprotein IIb/IIIa receptor) on the surface of platelets, inhibiting the binding of extracellular matrix proteins and thus inhibiting platelet aggregation and clot formation

Approved

1998 (USA)

1994 (US)

EGF, epidermal growth factor; hGH, human growth hormone; ICAM, intercellular adhesion molecules; LFA, lymphocyte function-associated antigen; TNF, tumor necrosis factor; VEGF, vascular endothelial growth factor.

GW

revenues from non–mAb-based therapeutic proteins are forecast to reach $52 billion by 2010 (ref. 3). In total, the total biopharmaceutical market should approach or perhaps exceed $70 billion by the end of the decade. From a technical standpoint, advances in protein engineering and delivery systems will underpin the approval of greater numbers of engineered products and products delivered nonparenterally. Mammalian cell lines will continue to be the most prominent production vehicle, at least in the immediate future. Transgenic systems still need to prove themselves, but advances in engineering cell lines to humanize protein glycosylation patterns stand a very real chance of facilitating the production of injectable proteins in plant- and yeastbased systems in the longer term. Such an advance, in addition to reducing production costs, should ease any bottleneck in manufacturing capacity underlining current mammalian cell–based systems. Cell culture capacity continues to increase. Current global capacity is estimated at 475,000 liters, with capacities of up to 20,000 liters reported for some of the larger biopharmaceutical companies22. Now that the approvability of biosimilars has been demonstrated, several additional such products will be approved, certainly outside of the United States—but also most

likely by the FDA as well—in the next three years. Initial approvals will probably focus on proteins devoid of post-translational modifications, particularly glycosylation, with more complex glycosylated molecules to follow. EPO’s sales value makes it a particularly attractive candidate, and the EMEA’s recent adoption of an annex biosimilar guideline specifically relating to erythropoietins shows further leadership in this regard. Despite Gendicine’s approval in China, gene therapy and other nucleic acid–based products

Indication

© 2006 Nature Publishing Group http://www.nature.com/naturebiotechnology

Table 3 (continued) Product

are unlikely to flood onto the European or US markets in the immediate future. Fundamental technical hurdles remain, particularly with regard to delivery. Notably, all such products approved thus far are administered locally, directly to the site of action. Satisfactory systemic delivery systems are required to render these technologies broadly applicable, and this remains a considerable technical challenge. Genomic and proteomic research will undoubtedly play an increasingly important role in pharmaceutical research, but such

Number of biologic candidates

Cancer* General research AIDS Infectious diseases* Drug delivery Gene therapy Melanoma Vaccines Hepatitis C Prostate cancer Breast cancer Lung cancer Leukemia Influenza Colon cancer Diagnostic* Immune system* Hepatitis B Diabetes Cardiovascular* 0

100

200

300

400

500

600

700

800

Number of biologic candidates

Figure 2 Biopharmaceuticals in the pipeline. (Source: Biopharm Insight, Norwood, MA.)

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© 2006 Nature Publishing Group http://www.nature.com/naturebiotechnology

F E AT U R E approaches will probably have a greater impact on drug target identification rather than on the direct identification of new biopharmaceuticals themselves. Pharmacogenomics and the promise of personalized medicine are also gaining increasing attention, in both traditional pharmaceutical and biopharma circles. Although routine approval of biopharmaceuticals specifically tailored to patient subsets is at best some way off, a few current products effectively work on this basis. ImClone’s (New York) chimeric antibody Erbitux (cetuximab) is indicated for the treatment of metastatic colorectal cancers that specifically express the epidermal growth factor (EGF) cell surface receptor; and Genentech’s (South San Francisco, CA) Herceptin (trastuzumab) specifically targets breast cancer cells that overexpress the human EGF-2 (HER-2) receptor. In the aftermath of the serious adverse events reported in volunteers participating in TeGenero’s phase 1 clinical study of the CD28 agonist mAb TGN1412, regulators are also likely to be scrutinizing more closely the animal models used to predict drug safety, efficacy and dosage in humans, especially for biopharmaceuticals with first-in-class mechanisms of action44. In particular, they may ask for preclinical testing of mAbs in animal models in which the antigenic site matches that in humans completely or in which the binding affinities of the animal antigen has been shown to be equivalent to those of the human form. In the big picture, however, idiosyncratic, unexpected and tragic adverse events of this type are probably an unavoidable drawback of introducing innovative drug therapies. Overall, the future looks promising for the biopharmaceutical sector. Over the coming few years, it will likely continue to grow and spur further innovation, although clearly the industry faces several technical and other challenges that should not be underestimated. 1. Lawrence, S. Biotech drug market steadily expands. Nat. Biotechnol. 23, 1466 (2005). 2. Pavlou, A. & Belsey, M. The therapeutic antibody market to 2008. Eur. J. Pharm. Biopharm. 59, 389–396 (2005). 3. Pavlou, A. & Reichert, J. Recombinant protein therapeutics—success rates, market trends and values to 2010. Nat. Biotechnol. 22, 1513–1519 (2004). 4. Walsh, G. Biopharmaceutical benchmarks—2003.

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Nat. Biotechnol. 21, 865–870 (2003). 5. World Health Organization. Diabetes Now http://www. idf.org/webdata/docs/diabetes_888k_version.pdf (2004). 6. Kjeldsen, T. Yeast secretory expression of insulin precursors. Appl. Microbiol. Biotechnol. 54, 277–286 (2000). 7. Walsh, G. Therapeutic insulins and their large-scale manufacture. Appl. Microbiol. Biotechnol. 67, 151– 159 (2005). 8. Brown, M., Martin, G., Jones, S. & Akomeah, F. Dermal and transdermal drug delivery systems: current and future prospects. Drug Deliv. 13, 175–187 (2006). 9. Chen, Y. et al. Transdermal protein delivery by a coadministered peptide identified via phage display technology. Nat. Biotechnol. 24, 455–460 (2006). 10. Hamman, J., Enslin, G.M. & Kotze, A.F. Oral delivery of peptide drugs—barriers and developments. BioDrugs 19, 165–177 (2005). 11. Orive, G., Hernández, R.M., Rodríguez Gascón, A., Domínguez-Gil, A. & Pedraz, J.L. Drug delivery in biotechnology: present and future. Curr. Opin. Biotechnol. 14, 659–664 (2003). 12. Upsher Smith Laboratories Inc. Fortical full prescribing information. http://www.upsher-smith.com/PDFs/ forticalpi.pdf (2005). 13. Patton, J.S., Bukar, J. & Nagarajan, S. Inhaled insulin. Adv. Drug Deliv. Rev. 35, 235–247 (1999). 14. Pfizer/Aventis. Exubera European Public Assessment Report. http://www.emea.eu.int/humandocs/PDFs/ EPAR/exubera/058806en1.pdf (2006). 15. Wildt, S. & Gerngross, T. The humanization of N-glycosylation pathways in yeast. Nat. Rev. Microbiol. 3, 119–128 (2005). 16. Gomord, W., Chamberlain, P., Jefferis, R. & Faye, L. Biopharmaceutical production in plants: problems, solutions and opportunities. Trends Biotechnol. 23, 559–565 (2005). 17. Chen, M. et al. Modification of plant N-glycan processing: the future of producing therapeutic protein by transgenic plants. Med. Res. Rev. 25, 343–360 (2005). 18. Gerngross, T.U. Advances in the production of human therapeutic proteins in yeasts and filamentous fungi. Nat. Biotechnol. 22, 1409–1414 (2004). 19. Jarvis, D. Developing baculovirus-insect cell expression systems for humanized recombinant glycoprotein production. Virology 310, 1–7 (2003). 20. Li, H. et al. Optimization of humanized IgGs in glycoengineered Pichia pastoris. Nat. Biotechnol. 24, 210–215 (2006). 21. Werten, M.W., Van de Bosch, T.J., Wind, R.D., Mooibroek, H. & De Wolf, F.A. High-yield secretion of recombinant gelatins by Pichia pastoris. Yeast 15, 1087–1096 (1999). 22. Butler, M. Animal cell cultures: recent achievements and perspectives in the production of biopharmaceuticals. Appl. Microbiol. Biotechnol. 68, 283–291 (2005). 23. CHMP (2006) Press release: Questions and answers on recommendation for refusal of marketing application for ATRYN (Committee for Medicinal Products for Human Use, London, 2006). 24. Ivarie, R. Competitive bioreactor hens on the horizon. Trends Biotechnol. 24, 99–101 (2006). 25. Zhu, L. et al. Production of human monoclonal antibody in eggs of chimeric chickens. Nat. Biotechnol. 23, 1159–1169 (2005).

26. Dyck, M. et al. Seminal vesicle production and secretion of growth hormone into seminal fluid. Nat. Biotechnol., 17, 1087–1090 (1999). 27. Ben-Maimon, C. & Garnick, R. Biogenerics at the crossroads. Nat. Biotechnol. 24, 268–269 (2006). 28. Diliberti, C. The best targets for biogenerics. BioPharm International 19, 50–64 (2006). 29. Fox, J. Sandoz sues FDA over delay in first biogeneric approval. Nat. Biotechnol. 23, 1327–1328 (2005). 30. Peng, Z. The genesis of Gendicine. BioPharm International 17, 42–49 (2004). 31. Peng, Z. Current status of Gendicine in China: recombinant human Ad-p53 agent for treatment of cancers. Hum. Gene Ther. 16, 1016–1027 (2005). 32. Wilson, J. Gendicine: the first commercial gene therapy product. Hum. Gene Ther. 16, 1014 (2005). 33. Verma, I. & Weitzman, M. Gene therapy: twenty first century medicine. Annu. Rev. Biochem. 74, 711–738 (2005). 34. Vidal, L., Blagden, S., Attard, G. & deBono, J. Making sense of antisense. Eur. J. Cancer 41, 2812–2818 (2005). 35. Khan, A. Ribozyme: a clinical tool. Clin. Chim. Acta 367, 20–27 (2006). 36. Dallas, A. & Vlassov, A. RNAi: a novel antisense technology and its therapeutic potential. Med. Sci. Monit. 12, RA67–RA74 (2006). 37. Jana S, Chakraborty C, Nandi S, Deb JK., RNA interference: potential therapeutic targets. Appl. Microbiol. Biotechnol. 65, 649-657 (2004). 38. Jana, S., Chakraborty, C., Nandi, S. & Deb, J.K. RNA interference: potential therapeutic targets. Appl. Microbiol. Biotechnol. 65, 649–657 (2004). 39. Zimmermann, T.S. et al. RNAi-mediated silencing in non-human primates. Nature 441, 111–114 (2006). 40. Hermeling, S., Schellekens, H., Crommelin, D. & Jiskoot, W. Micelle-associated protein in Epoetin formulations: a risk factor for immunogenicity? Pharm. Res. 20, 1903–1907 (2003). 41. Villalobos, A.P., Gunturi, S.R. & Heavner, G.A. Interaction of polysorbate 80 with erythropoietin: a case study in protein-surfactant interactions. Pharm. Res. 22, 1186–1194 (2005). 42. Hermeling, S., Jiskoot, W., Crommelin, D. & Schellekens, H. Reaction to the paper: interaction of polysorbate 80 with erythropoietin: a case study in protein-surfactant interactions. Pharm. Res. 23, 641–642 (2006). 43. Lim, L.C. Acquired red cell aplasia in association with the use of recombinant erythropoietin in chronic renal failure. Hematology (Am. Soc. Hematol. Educ. Program) 10, 255–259 (2005). 44. Sheridan, C. TeGenero fiasco prompts regulatory rethink. Nat. Biotechnol. 24, 475–476 (2006). 45. Proske, D., Blank, M., Buhmann, R., & Resch A. Aptamers—basic research, drug development, and clinical applications. Appl. Microbiol. Biotechnol. 69, 367–374 (2005). 46. Nimjee, S.M., Rusconi, C.P. & Sullenger, B.A. Aptamers, an emerging class of therapeutics. Annu. Rev. Med., 56, 555–583 (2005). 47. Hey, T., Fiedler, E., Rudolph, R. & Fiedler, M. Artificial, non-antibody binding proteins for pharmaceutical and industrial applications. Trends Biotechnol, 23, 514–522 (2005). 48. Binz, H.K., Amstutz, P. & Pluckthun, A. Engineering novel binding proteins from nonimmunoglobulin domains. Nat. Biotechnol. 23, 1257–1268 (2005).

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B I O P H A R M AC E U T I CA L

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Benchmarks

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class) Product

Company

Therapeutic indication

Alfatronol (rh IFN-α-2b produced in E. coli)

Schering-Plough

Hepatitis B, C and various cancers

2000 (EU)

Rebetron (combination of ribavirin and rh IFN-α-2b produced in E. coli)

Schering-Plough

Chronic hepatitis C

1999 (US)

Infergen (r IFN-α, synthetic type I IFN produced in E. coli)

Amgen (US), Yamanouchi Europe (Leiderdorp, The Netherlands) (EU)

Chronic hepatitis C

1997 (US), 1999 (EU)

Roferon A (rh IFN-α-2a produced in E. coli)

Hoffmann–La Roche

Hairy-cell leukemia

1986 (US)

Rebif (rh IFN-β-1a produced in CHO cells)

Ares Serono (Geneva)

Relapsing/remitting multiple sclerosis

1998 (EU,) 2002 (US)

Avonex (rh IFN−β1a produced in CHO cells)

Biogen (Cambridge, MA)

Relapsing multiple sclerosis

1997 (EU), 1996 (US)

Therapeutic indication

Betaferon (r IFN-β1b differing from human protein by C17S substitution; produced in E. coli)

Schering AG

Multiple sclerosis

1995 (EU)

Betaseron (rIFM-β1b, differing from human protein by Cys17Ser substitution; produced in E. coli)

Berlex Labs (Richmond, CA, USA)/ Chiron (Emeryville, CA, USA)

Relapsing/remitting multiple sclerosis

1993 (US)

Kineret (anakinra; r IL-1 receptor antagonist produced in E. coli)

Amgen

Rheumatoid arthritis

2001 (US)

Neumega (r IL-11, lacking N-terminal proline of native molecule; produced in E. coli.)

Genetics Institute

Prevention of chemotherapyinduced thrombocytopenia

1997 (US)

Proleukin (r IL-2, differing from human molecule in absence of an N-terminal alanine and a C125S substitution produced in E. coli)

Chiron

Renal-cell carcinoma

1992 (US)

Actimmune (rh IFN-γ1b; produced in E. coli)

Genentech

Chronic granulomatous disease

1990 (US)

Ambirix (combination vaccine containing rHBsAg produced in S. cerevisiae as one component)

GlaxoSmith Kline (GSK, Brentford, UK)

Immunization against hepatitis A and B

2002 (EU)

Pediarix (combination vaccine containing rHBsAg produced in S. cerevisiae as one component)

GSK

Immunization of children against various conditions inducing hepatitis B

2002 (US)

HBVAXPRO (rHBsAg produced in S. cerevisiae)

Aventis Pharma

Immunization of children and adolescents against hepatitis B

2001 (EU)

Twinrix (adult and pediatric forms in EU; combination vaccine containing rHBsAg produced in S. cerevisiae as one component)

GSK (US, EU)

Immunization against hepatitis A and B

Infanrix-Hexa (combination vaccine containing rHBsAg produced in S. cerevisiae as one component)

GSK

Immunization against diphtheria, tetanus, pertussis, Haemophilus influenzae type b, hepatitis B and polio

2000 (EU)

Infanrix-Penta (combination vaccine, containing rHBsAg produced in S. cerevisiae as one component)

GSK

Immunization against diphtheria, tetanus, pertussis, polio and hepatitis B

2000 (EU)

Hepacare (r S, pre-S & pre-S2 HBsAgs produced in a mammalian (murine) cell line)

Medeva Pharma (Rochester, NY)

Immunization against hepatitis B

2000 (EU)

Hexavac (combination vaccine containing rHBsAG produced S. cerevisiae as one component)

Aventis Pasteur (Lyon, France)

Immunization against diphtheria, tetanus, pertussis, hepatitis B, polio and H. influenzae type b

2000 (EU)

Procomvax (combination vaccine containing r HBsAg as one component)

Aventis Pasteur

Immunization against H. influenzae type b and hepatitis B

1999(EU)

Primavax (combination vaccine containing r HBsAg produced in S. cerevisiae as one component)

Aventis Pasteur

Immunization against diphtheria tetanus and hepatitis B

1998 (EU)

Infanrix Hep B (combination vaccine containing rHBsAg produced in S. cerevisiae as one component)

GSK

Immunization against diphtheria, tetanus, pertussis and hepatitis B

1997 (EU)

Twinrix, adult and pediatric forms (combination vaccine containing r HBsAg produced in S. cerevisiae as one component)

GSK

Immunization against hepatitis A and B

Company

Therapeutic indication

Date approved

Recombinant hormones

Other hormones

Insulin

*Fortical (r salmon calcitonin produced in E. coli)

Levemir (insulin detemir, long-acting rh insulin analog produced in S. cerevisiae)

Pfizer (New York)/ Aventis (Kent, UK)

Diabetes mellitus

Novo Nordisk

Diabetes mellitus

Therapeutic indication

Date approved

Upsher-Smith Laboratories (Minneapolis, MN, USA)/ Unigene (Fairfield, NJ, USA)

Postmenopausal osteoporosis

*Luveris (lutropin α; rh luteinizing hormone produced in CHO cells)

Ares-Serono (Geneva)

Some forms of infertility

2004 (US), 2000 (EU)

Forteo teriparatide (r shortened form of human parathyroid hormone produced in E. coli; also sold as Forsteo in the EU)

Eli Lilly

Established osteoporosis in postmenopausal women

2003 (EU)

2006 (EU and US)

2005 (US), 2004 (EU)

Company

2005 (US), 2003 (EU)

Ovitrelle also termed Ovidrelle (rhCG produced in CHO cells)

Serono

Selected assisted reproductive techniques

2001 (EU), 2000 (US)

Thyrogen (thyrotrophin-a, rhTSH produced in CHO cells)

Genzyme (Cambridge, CA)

Thyroid cancer (detection and treatment)

1998 (US), 2000 (EU)

Forcaltonin (r salmon calcitonin produced in E. coli)

Unigene

Paget disease

1999 (EU)

Glucagen (rh glucagon produced in S. cerevisiae)

Novo Nordisk

Hypoglycemia

1998 (US)

Apidra (insulin glulisine, rapid-acting insulin analog produced in E. coli)

Aventis (Germany)

Diabetes mellitus

2004 (EU and US)

Actrapid/Velosulin/Monotard/Insulatard/Protaphane/Mixtard/ Actraphane/Ultratard (all contain rh insulin produced in S. cerevisiae formulated as short-, intermediate- or long-acting product)

Novo Nordisk

Diabetes mellitus

2002 (EU)

Novolog (insulin aspart, short-acting rh insulin analog produced in S. cerevisiae).

Novo Nordisk

Novolog mix 70/30 (contains insulin aspart, short-acting rh insulin analog, as one ingredient; see also Novomix 30)

Novo Nordisk

Diabetes mellitus

2001 (US)

Erythropoietin

Novo Nordisk

Diabetes mellitus

2000 (EU)

Amgen (Woodland Hills, CA)

2001 (US and EU)

Novomix 30 (contains insulin aspart, short-acting rh insulin analog, as one ingredient)

Aranesp (darbepoetin α; long-acting rEPO analogue produced in CHO cells)

Anemia

2004 (EU), 2003 (US)

Nespo (darbepoetin α; see also Aranesp; long-acting rEPO analogue produced in CHO cells)

Dompe Biotec (Milan, Italy)

Anemia

2001 (EU)

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class) Company

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class) Product

Exubera (rh insulin produced in E. coli)

The biopharmaceuticals currently approved in the US or EU are summarized in Table 1. Eight categories are shown (recombinant blood factors, recombinant thrombolytics and anticoagulants, recombinant hormones, recombinant growth factors, recombinant interferons and interleukins, recombinant vaccines, monoclonal antibody-based products, and miscellaneous recombinant products). Data were collected from several industry sources (http://www.fda.gov, http://www.eudra.org/en_home.htm, http://www.phrma.org).

Product

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class) Product

Date approved

Recombinant blood factors Factor VIII

Diabetes mellitus

2001 (US)

Recombinant growth factors

Advate (octocog-α rh Factor VIII produced in CHO cell line grown in serum-free medium free from animal products)

Baxter (Leverkusen, Germany)

Hemophilia A

Helixate NexGen (octocog α; rh Factor VIII produced in BHK cells)

Bayer

Hemophilia A

2000 (EU)

Lantus (insulin glargine, long-acting rh insulin analog produced in E. coli)

Aventis

Diabetes mellitus

2000 (EU and US)

Neorecormon (rh EPO produced in CHO cells)

Roche

Anemia

1997 (EU)

ReFacto (moroctocog-α B-domain-deleted rh Factor VIII produced in CHO cells)

Genetics Institute (Cambridge, MA, USA), Wyeth Europa (Maidenhead, UK)

Hemophilia A

1999 (EU), 2000 (US)

Optisulin (Insulin glargine, long-acting rh insulin analog produced in E. coli; see Lantus)

Aventis

Diabetes mellitus

2000 (EU)

Procrit (rh EPO produced in a mammalian cell line)

Ortho Biotech (Bridgewater, NJ)

Anemia

1990 (US)

NovoRapid (insulin aspart, rh insulin analog)

Novo Nordisk

Diabetes mellitus

1999 (EU)

Epogen (rh EPO produced in a mammalian cell line)

Amgen

Anemia

1989 (US)

Liprolog (Bio Lysprol, insulin analog produced in E. coli)

Eli Lilly

Diabetes mellitus

1997 (EU)

Granulocyte–macrophage colony-stimulating factor

Insuman (rh insulin produced in E. coli)

Hoechst AG (Frankfurt, Germany)

Diabetes mellitus

1997 (EU)

Neulasta (pegfilgrastim, r pegylated GM-CSF (filgrastim); also marketed in EU as Neupopeg)

Amgen, Dompec Biotech

Chemotherapy-induced neutropenia

2002 (US and EU)

Leukine (r GM-CSF, differing from the native human protein by one amino acid, Leu23; produced in E. coli)

Immunex (now Amgen)

Autologous bone marrow transplantation

1991 (US)

Chemotherapy-induced neutropenia

1991 (US)

Kogenate (rh Factor VIII produced in BHK cells; also sold as Helixate by Aventis Behring through a license agreement)

Bayer

Bioclate (rh Factor VIII produced in CHO cells)

Aventis Behring (King of Prussia, PA, USA)

Recombinate (rh Factor VIII produced in an animal cell line)

Hemophilia A

Hemophilia A

Baxter Healthcare (Deerfield, IL, USA)/ Genetics Institute

Hemophilia A

NovoSeven (rh Factor VIIa produced in BHK cells)

Novo Nordisk (Bagsvaerd, Denmark)

Some forms of hemophilia

Benefix (rh Factor IX produced in CHO cells)

Genetics Institute

Hemophilia B

1993 (US), 2000 (EU) 1993 (US)

Humalog (insulin lispro, insulin analog produced in E. coli)

Eli Lilly

Diabetes mellitus

1996 (US and EU)

1992 (US)

Novolin (rh insulin)

Novo Nordisk

Diabetes mellitus

1991 (US)

Humulin (rh insulin produced in E. coli)

Eli Lilly

Diabetes mellitus

1982 (US)

1996 (EU), 1999 (US) 1997 (US and EU)

Valtropin (somatropin, rh GH produced in S. cerevisiae)

Omnitrop (somatropin, rh GH produced in E. coli)

Biopartners

Sandoz (Basel)

Recombinant thrombolytics and anticoagulants Tissue plasminogen activator Tenecteplase (also marketed as Metalyse) (TNK-tPA, modified r tPA produced in CHO cells)

Boehringer Ingelheim (Ridgefield, CT, USA)

Myocardial infarction

2001 (EU)

TNKase (tenecteplase; modified r tPA produced in CHO cells; see Tenecteplase)

Genentech (S. San Francisco, CA, USA)

Myocardial infarction

2000 (US)

Ecokinase (reteplase, r tPA produced in Escherichia coli; differs from human tPA in that three of its five domains have been deleted)

Galenus Mannheim (Germany)

Acute myocardial infarction

1996 (EU)

Rapilysin (reteplase, r tPA; see Ecokinase)

Roche (Basel)

Acute myocardial infarction

1996 (EU)

Retavase (reteplase, r tPA; see Ecokinase)

Boehringer Mannheim/ Centocor (Malvern, PA, USA)

Acute myocardial infarction

1996 (US)

Genentech

Acute myocardial infarction

Activase (alteplase, rh tPA produced in CHO cells) Refludan (anticoagulant; recombinant hirudin produced in Saccharomyces cerevisiae)

Revasc (anticoagulant; recombinant hirudin produced in S. cerevisiae)

Hoechst Marion Roussel (US) (Bridgewater, NJ, USA), Behringwerke AG (Marburg, German) (EU)

Anticoagulation therapy for heparin-associated thrombocytopenia

Canyon Pharmaceuticals (London)

Prevention of venous thrombosis

1997 (EU), 1998 (US)

1997 (EU)

Certain forms of growth disturbance in children and adults

2006 (EU)

Pfizer

Acromegaly

2003 (US), 2002 (EU)

Nutropin AQ (r hGH produced in E coli)

Schwartz Pharma (Duesseldorf, Germany)

Growth failure/Turner syndrome

2001 (EU), 1994 (US)

Serostim (r hGH)

Serono Laboratories (Geneva)

AIDS-associated catabolism and wasting

1996 (US)

Saizen (r hGH)

Serono Laboratories

hGH deficiency in children

1996 (US)

Genotropin (r hGH produced in E. coli)

Pharmacia & Upjohn (Peapack, NJ, USA)

hGH deficiency in children

1995 (US)

Norditropin (r hGH)

Novo Nordisk

Growth failure in children due to inadequate growth hormone secretion

1995 (US)

BioTropin (r hGH)

Savient Pharmaceuticals (Iselin, NJ, USA)

hGH deficiency in children

1995 (US)

Nutropin (r hGH produced in E. coli)

Genentech

hGH deficiency in children

1994 (US)

Humatrope (r hGH produced in E. coli)

Eli Lilly

hGH deficiency in children

1987 (US)

Protropin (r hGH differing from hGH only in containing an additional N-terminal methionine residue; produced in E. coli)

Genentech

hGH deficiency in children

1985 (US)

Follicle-stimulating hormone

Xigris (drotrecogin-α; rh activated protein C produced in a mammalian (human) cell line)

Follistim (follitropin-β, rh FSH produced in CHO cells)

NV Organon (West Orange, NJ, USA)

Infertility

1997 (US)

Puregon (rh FSH produced in CHO cells)

N.V. Organon

Anovulation and superovulation

1996 (EU)

Gonal F (rh FSH produced in CHO cells)

Ares-Serono (Geneva)

Anovulation and superovulation

1995 (EU), 1997 (US)

NATURE BIOTECHNOLOGY VOLUME 24 NUMBER 7 JULY 2006

Severe sepsis

2001 (US), 2002 (EU)

Tercica (Brisbane, CA, USA)/ Baxter

Growth failure in children with severe primary IGF-1 deficiency or GH gene deletion (long-term treatment)

2005 (US)

IPlex (mecasermin rinfabate, a complex of rh IGF-1 and rh IGFBP-3 produced separately in E. coli)

Insmed (Glen Allen, VA, USA)

Growth failure in children with severe primary IGF-1 deficiency or GH gene deletion (long-term treatment)

2005 (US)

Kepivance (palifermin, a recombinant keratinocyte growth factor produced in E. coli)

Amgen

Severe oral mucositis in selected patients with hematologic malignancies

2005 (EU), 2004 (US)

GEM 21S (growth factor enhanced matrix; contains rhPDGF-BB and tricalcium phosphate)

Luitpold Pharmaceuticals (Shirley, NY, USA), BioMimetic Pharmaceuticals (Franklin, TN, USA)

Periodontally related defects

2005 (US)

Regranex (rh PDGF produced in S. cerevisiae)

Ortho-McNeil Pharmaceutical (Raritan, NJ), Janssen-Cilag (EU)

Lower-extremity diabetic neuropathic ulcers

1997 (US), 1999 (EU)

Pegasys (PEGinterferon α-2a produced in E. coli)

Hoffman–La Roche (Nutley, NJ)

Hepatitis C

PegIntron A (PEGylated rIFN-α-2b produced in E. coli)

Schering-Plough (Kenilworth, NJ, USA)

Chronic hepatitis C

2000 (EU), 2001 (US)

Viraferon (rIFN-α-2b produced in E. coli)

Schering-Plough

Hepatitis B, C

2000 (EU)

ViraferonPeg (PEGylated rIFN-α-2b produced in E. coli)

Schering-Plough

Chronic Hepatitis C

2000 (EU)

Alfatronol (rhIFN-α-2b produced in E coli)

Schering-Plough

Hepatitis B, C and various cancers

2000 (EU)

Viraferon (rhIFN-α-2b produced in E. coli)

Schering-Plough

Hepatitis B, C

2000 (EU)

Intron A (rIFN-α-2b produced in E. coli)

Schering-Plough

Cancer, genital warts, Hepatitis

1986 (US), 2000 (EU)

Recombinant interferons and interleukins

Other Eli Lilly (Indianapolis, IN)

Increlex (mecasermin, rh IGF-1 produced in E. coli)

2006 (EU and US)

Somavert (pegvisomant; hGH analog (antagonist) produced in E. coli)

1987 (US)

Hirudin

Certain forms of growth disturbance in children and adults

Interferon-β

Others

Recombinant vaccines

Other growth factors

Human growth hormone

Other blood factors

Neupogen (filgrastim, r GM-CSF differing from human protein by Amgen containing an additional N-terminal methionine; produced in E. coli)

Date approved

Hepatitis B

Interferon-α 2002 (EU and US)

1996 (EU, adult), 1997 (EU, pediatric), 2001 (US)

1996 (EU, adult), 1997 (EU, pediatric)

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class)

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class)

Table 1 Biopharmaceuticals approved in the United States and Europe (listed consecutively from most recent approval in each class)

Table 2 Selected examples of bioengineered therapeutics

Product

Company

Therapeutic indication

Product

Company

Therapeutic indication

Product

Company

Therapeutic indication

Product

Nature of engineering

Rationale for engineering

Comvax (combination vaccine containing HbsAg produced in S. cerevisiae as one component)

Merck (Whitehouse Station,NJ, USA)

Vaccination of infants against H. influenzae type B and hepatitis B

1996 (US)

Simulect (basiliximab, chimeric mAb directed against the α-chain of the IL-2 receptor)

Novartis

Prophylaxis of acute organ rejection in allogeneic renal transplantation

1998 (EU)

Vitravene (fomivirsen, an antisense oligonucleotide)

Isis Pharmaceuticals (Carlsbad, CA, USA)

Treatment of cytomegalovirus retinitis in AIDS patients

1998 (US)

Levemir (insulin detemir)

Devoid of insulin B30 threonine residue, and with a C14 fatty acid covalently attached to B29 lysine

Tritanrix-HB (combination vaccine containing r HBsAg produced in S. cerevisiae as one component)

GSK

Vaccination against hepatitis B, diphtheria, tetanus and pertussis

1996 (EU)

LeukoScan (sulesomab, murine mAb fragment (Fab) directed against NCA 90, a surface granulocyte nonspecific cross-reacting antigen)

Immunomedics (Morris Plains, NJ, USA)

Diagnostic imaging for infection and inflammation in bone of patients with osteomyelitis

1997 (EU)

Amevive (alefacept, a dimeric fusion protein consisting of the extracellular CD2-binding portion of the human LFA-3 linked to the Fc region of human IgG1; produced in CHO cells)

Biogen

Treatment of adults with moderate to severe chronic plaque psoriasis

2003 (US)

Generation of long-acting insulin: fatty acid attachment facilitates binding of product to serum albumin both at the injection site and in the blood, ensuring a constant and prolonged release of free insulin

Apidra (insulin glulisine)

Insulin B3 asparagine residue replaced by lysine and B29 lysine replaced by glutamic acid

Recombivax (r HBsAg produced in S. cerevisiae)

Merck

Hepatitis B prevention

1986 (US)

Rituxan (rituximab chimeric mAb directed against CD20 antigen found on the surface of B lymphocytes)

Genentech/Biogen/IDEC

Non-Hodgkin lymphoma

1997 (US)

Enbrel (rTNF receptor–IgG fragment fusion protein produced in CHO cells)

Amgen (US); Wyeth (EU)

Rheumatoid arthritis

1998 (US), 2000 (EU)

Generation of a rapid insulin: the substitutions reduce interchain interaction, promoting rapid insulin hexamer disassociation at the site of injection and hence rapid entry into the blood

Gardasil (quadrivalent human papillomavirus (HPV) recombinant vaccine; contains major caspid proteins from four HPV types, produced in S. cerevisiae)

Merck

Therapeutic indication: Vaccination against diseases caused by HPV

2006 (US)

Verluma (nofetumomab murine mAb fragments (Fab) directed against carcinoma-associated antigen)

Boehringer Ingelheim/NeoRx

Detection of small-cell lung cancer

1996 (US)

Beromun (rh TNF-α produced in E. coli)

Boehringer Ingelheim

1999 (EU)

Forteo (teriparatide)

SBL Vaccin AB (Stockholm)

Active immunization against disease caused by Vibrio cholerae subgroup O 1

2004 (EU)

Diagnosis of cutaneous melanoma lesions

1996 (EU)

Dukoral (Vibrio cholerae and recombinant cholera toxin B subunit)

Sorin (Saluggia, Italy)

Identical in sequence to residues 1–34 of the 84-amino-acid endogenous human parathyroid hormone (PTH)

Generation of a shorter form of PTH that still has full PTH activity

Tecnemab KI (murine mAb fragments (Fab/Fab2 mix) directed against HMW-MAA)

Adjunct to surgery for subsequent tumor removal, to prevent or delay amputation

Kepivance (palifermin)

Detection, staging and follow-up of prostate adenocarcinoma

1996 (US)

Seragen/Ligand Pharmaceuticals (San Diego, CA, USA)

1999 (US)

Cytogen (Princeton, NJ, USA)

Ontak (r IL-2–diphtheria toxin fusion protein that targets cells displaying a surface IL-2 receptor)

Cutaneous T-cell lymphoma

ProstaScint (capromab pentetate murine mAb directed against the tumor surface antigen PSMA)

Differs from native keratinocyte growth factor (KGF) only in that its devoid of the initial 23 N-terminal amino acid residues

Generation of a form of KGF that has full biological activity and improved stability

Lymerix (r OspA, a lipoprotein found on the surface of Borrelia burgdorferi; produced in E. coli)

GSK

Lyme disease vaccine

1998 (US)

MyoScint (imiciromab pentetate, murine mAb fragment directed against human cardiac myosin)

Centocor

Myocardial infarction imaging agent

1996 (US)

Somavert (pegvisomant)

Differs from native human growth hormone (hGH) by 9 amino acid substitutions and is PEGylated

Tricelluvax (combination vaccine containing r modified pertussis toxin as one component)

Chiron Srl (Siena, Italy)

Immunization against diphtheria, tetanus and pertussis

1999 (EU).

CEA-scan (arcitumomab, murine mAb fragment (Fab) directed against human carcinoembryonic antigen (CEA))

Immunomedics

Detection of recurrent/ metastatic colorectal cancer

Generation of an hGH analog (antagonist) that binds the hGH receptor but does not trigger signal transduction; PEGylation increases its serum half-life

Erbitux (cetuximab)

Chimeric antibody

Indimacis 125 (igovomab, murine mAb fragment (Fab2) directed against the tumor-associated antigen CA 125)

CIS Bio (Gif-sur-Yvette, France)

Diagnosis of ovarian adenocarcinoma

1996 (EU)

Reduction of antibody immunogenicity and facilitation of human effector functions

Xolair (omalizumab)

Humanized mAb antibody

ReoPro (abciximab, Fab fragments derived from a chimeric mAb,directed against the platelet surface receptor GPIIb/IIIa)

Centocor

Prevention of blood clots

1994 (US)

Reduction or elimination of antibody immunogenicity and facilitation of human effector functions

Raptiva (efalizumab)

Humanized mAb antibody

OncoScint CR/OV (satumomab pendetide, murine mAb directed against the tumor-associated glycoprotein TAG-72)

Cytogen

Detection, staging and followup of colorectal and ovarian cancers

1992 (US)

Reduction or elimination of antibody immunogenicity and facilitation of human effector functions

Avastin (bevacizumab)

Humanized mAb Antibody

Reduction or elimination of antibody immunogenicity and facilitation of human effector functions

Orthoclone OKT3 (muromomab CD3, murine mAb directed against the T-lymphocyte surface antigen CD3)

Ortho Biotech

Reversal of acute kidney transplant rejection

1986 (US)

Tysabri (natalizumab)

Humanized mAb antibody

Reduction or elimination of antibody immunogenicity and facilitation of human effector functions

Amevive (alefacept)

Fusion protein consisting of the extracellular human leukocyte functional antigen 3 domain linked to an IgG fragment

Targeting of lymphocytes predominantly involved in psoriatic lesions and facilitation of cellular destruction (through attracting natural killer and other cytotoxic cells) by immunoglobulin portion

Macugen (pegaptanib sodium)

Synthetic nucleotide sequence that is PEGylated

Increase in half-life

Date approved

Other

Monoclonal antibody–based products *Xolair (omalizumab; humanized mAb that binds IgE at the site of high-affinity IgE receptor binding)

Genentech/Novartis/Tanox (Houston, TX, USA)

Moderate to severe persistent asthma in adults and adolescents

2005 (EU), 2003 (US)

*Zevalin (ibritumomab tiuxetan; murine mAb targeted against the CD20 antigen, produced in a CHO cell line)

Biogen/IDEC (Cambridge, MA, USA) (US), Schering AG (EU)

Non-Hodgkins lymphoma

2004 (EU), 2002 (US

Erbitux (cetuximab; chimeric antibody raised against human EGF receptor)

ImClone Systems (New York) and Bristol-Myers Squibb (New York) (US), Merck (EU)

EGF receptor–expressing metastatic colorectal cancer

Raptiva (efalizumab; humanized mAb that binds to LFA-1, which is expressed on all leukocytes; produced in a CHO cell line)

Genentech (USA) Serono (EU)

Chronic moderate to severe plaque psoriasis in adults

2004 (EU,) 2003 (US)

Avastin (bevacizumab; humanized mAb raised against vascular endothelial growth factor; produced in a CHO cell line)

Genentech (USA) Roche (EU)

Carcinoma of the colon or rectum

2004 (US), 2005 (EU)

Tysabri (natalizumab; humanized mAb raised against selected leukocyte integrins; produced in a mammalian cell line)

Biogen Idec/Elan (Dublin)

Patients with relapsing forms of multiple sclerosis

NeutroSpec (fanolesomab; murine mAb raised against CD15 surface antigen of selected leukocytes; produced in hybridoma cells)

Palatin Technologies (Cranbury, Imaging of equivocal appendicitis NJ, USA)/Mallinckrodt (Hazelwood, MO, USA)

2004 (US)

*Humira (EU and USA; also sold as Trudexa in EU) (adalimumab; rh (anti-TNF) monoclonal antibody created using phage-display technology)

Cambridge Antibody Technology & Abbott (US) Abbott (EU)

Rheumatoid arthritis

2003 (EU), 2002 (US)

Bexxar (tositumomab; radiolabeled mAb directed against CD20 antigen, produced in a mammalian cell line)

GSK

Treatment of CD20-positive follicular non-Hodgkins lymphoma

2003 (US)

Mabcampath (EU) or Campath (US) (alemtuzumab; a humanized mAb directed against CD52 surface antigen of B lymphocytes)

Millennium (Cambridge, MA, USA) & Genzyme (EU); Berlex (Montville, NJ, USA) & Millennium (US)

Chronic lymphocytic leukemia

Mylotarg (gemtuzumab zogamicin; humanized antibody-toxic antibiotic conjugate targeted against CD33 antigen found on leukemic blast cells)

Wyeth (Madison, NJ, USA)

Acute myeloid leukemia

2000 (US)

Herceptin (trastuzumab, humanized antibody directed against HER2)

Genentech (US), Roche (EU)

Metastatic breast cancer overexpressing HER2 protein

1998 (US), 2000 (EU)

Remicade (infliximab, chimeric mAb directed against TNF-α)

Centocor (Horsham, PA, USA)

Treatment of Crohn disease

1998 (US), 1999 (EU)

Synagis (palivizumab, humanized mAb directed against an epitope on the surface of respiratory syncytial virus)

MedImmune (Gaithersburg, MD, USA) (US), Abbott (EU)

Prophylaxis of lower-respiratorytract disease caused by the virus in pediatric patients

1998 (US), 1999 (EU)

Zenapax (daclizumab, humanized mAb directed against the α-chain of the IL-2 receptor)

Hoffmann–La Roche

Prevention of acute kidney transplant rejection

1997 (US), 1999 (EU)

Humaspect (votumumab, human mAb directed against cytokeratin tumor-associated antigen)

Organon Teknika (Durham, NC, USA)

Detection of carcinoma of the colon or rectum

1998 (EU)

Mabthera (rituximab, chimeric mAb directed against CD20 surface antigen of B lymphocytes; see also Rituxan)

Hoffmann–La Roche

Non-Hodgkin lymphoma

1998 (EU)

NATURE BIOTECHNOLOGY VOLUME 24 NUMBER 7 JULY 2006

2004 (US and EU)

Date approved

Date approved

Other

1996 (US and EU)

Other recombinant products

Boldface indicates products approved from 2003 to June 2006. Asterisk indicates 2003 products listed in the previous benchmark article (which covered those approved up to June 2003). BHK, baby hamster kidney; BMP, bone morphogenetic protein; CHO, Chinese hamster ovary; EPO, erythropoietin; FSH, follicle-stimulating hormone; GM-CSF, granulocyte-macrophage colony-stimulating factor; HER, human epidermal growth factor receptor; hGH, human growth hormone; Ig, immunoglobulin; IL, interleukin; LFA, leukocyte functional antigen; mAb, monoclonal antibody; NK, natural killer; PDFG, platelet-dependent growth factor; r, recombinant; rh, recombinant human; rHBsAg, recombinant hepatitis B surface antigen, tPA, tissue plasminogen activator; TNF, tumor necrosis factor; TNK, tenecteplase; TSH, thyroid-stimulating hormone.

Bone morphogenetic proteins

2004 (US), suspended 2005

Infuse bone graft (contains dibotermin α, a rh BMP-2 produced in CHO cells placed on an absorbable collagen sponge. Note: this is the same active ingredient present in the product Infuse, approved in the USA in 2002.)

Wyeth

Inductos (dibotermin α; r BMP-2 produced in CHO cells)

Genetics Institute, Wyeth Europa

Treatment of acute tibia fractures

2002 (EU)

Infuse (rh BMP-2 produced in CHO cells)

Medtronic Sofamor Danek (Memphis, TN, USA)

Promotes fusion of lower spine vertebrae

2002 (US)

Osteogenic protein 1 (rh osteogenic protein 1 BMP-7, produced in CHO cells)

Howmedica (Allendale, NJ, USA) (EU); Stryker (Kalamazoo, MI, USA) (US)

Treatment of non-union of tibia

2001 (EU and US)

Myozyme (algulcosidase α, rh acid glucosidase produced in a CHO cell line)

Genzyme

Pompe disease

2006 (EU and US)

Aldurazyme (laronidase; rh α-L-iduronidase produced in an engineered CHO cell line)

Genzyme, BioMarin Pharmacuetials (Novato, CA)

Long-term enzyme replacement therapy in patients with mucopolysaccharidosis I

2006 (EU), 2003 (US)

Naglazyme (galsulfase, rh N-acetylgalactosamine 4 sulfatase produced in a CHO cell line)

BioMarin Pharmaceuticals

Long-term enzyme replacement therapy in patients with mucopolysaccharidosis VI

2006 (EU), 2005 (US)

Hylenex (rh hyaluronidase produced in CHO cells)

Baxter/Halozyme Therapeutics

Adjuvant to increase absorption and dispersion of other drugs

2005 (US)

Fabrazyme (rh α-galactosidase produced in CHO cells)

Genzyme

Fabry disease (α-galactosidase A deficiency)

2003 (US), 2001 (EU)

Replagal (rh α-galactosidase produced in a continuous human cell line)

TKT Europe (Danderyd, Sweden)

Fabry disease (α-galactosidase A deficiency)

2001 (EU)

Fasturtec (Elitex in US) (rasburicase; r urate oxidase produces in S. cerevisiae)

Sanofi-Synthelabo (Paris)

Hyperuricemia

2001 (EU), 2002 (US)

Pulmozyme (dornase-α, r DNase produced in CHO cells)

Genentech

Cystic fibrosis

1993 (US)

Eyetech (New York)/ Pfizer

Neovascular, age-related macular degeneration

2006 (EU), 2004 (US)

Treatment of acute open tibial shaft fracture

2004 (US)

Recombinant enzymes

2001 (EU and US)

Nucleic acid–based products Macugen (pegaptanib sodium injection, a synthetic pegylated oligonucleotide that specifically binds vascular endothelial growth factor)