Commercial Biotechnology - Princeton University

PART III

Applications of Biotechnology inSpecific Industrial Sectors

Chapter 5

Pharmaceuticals

Contents

PageIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119Regulatory Proteins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

Human Insulin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120Interferon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122Human Growth Hormone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127Neuroactive Peptides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128Lymphokines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130Other Regulatory Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Blood Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131Human Serum Albumin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132Antihemophilic Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133Thrombolytic and Fibrinolytic Etnzymes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

Vaccines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136Viral Disease Vaccines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136Bacterial Disease Vaccines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139Parasitic Disease Vaccines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Antibiotics, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143Monoclinal Antibodies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Diagnostic Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144Preventive and Therapeutic Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

DNA Hybridization Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148Commercial Aspects of Biotechnology in the Pharmaceutical Industry . . . . . . . . . . . . . . . 150Priorities For Future Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151Chapter 5 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152

Tables

Table No. Page15.U.S. and European Markets for Insulin: Eli Lilly’s Estimated Sales . . . . . . . . . . . . . . . . 12116. Some Ongoing Clinical Trials Using Alpha or Beta Interferon

To Treat Human Viral Diseases. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12417. Some Ongoing Clinical Trials of the Use of Interferons To Treat Cancer . . . . . . . . . . 12618.Some U.S. and Foreign Companies Involved in Interferon Gene Cloning Projects . . . 12819. Some Proteins With Possible Pharmaceutical Applications

Being Developed With Recombinant DNA Technology . . . . . . . . . . . . . . . . . . . . . . . . . . 12920. Some Protein “Growth Factors’’With Potential Pharmaceutical Applications . . . . . . . 13121. Human Serum Albumin Production and Consumption in the United States . . . . . . . . 13222. Antihemophilic Factor Production and Consumption in the World . . . . . . . . . . . . . . . 13323.Thrombolytic and Fibrinolytic Enzymes:

Companies Involved in Development and Marketing . . . . . . . . . . . . . . . . . . . . . . . . . . . 13s24. Some Current Viral Vaccine Biotechnology Projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13725. Estimated Worldwide Populations Affectedly Parasitic Diseasesin 1971 . . . . . . . . . 14026. In Vitro Monoclinal Antibody Diagnostic Products Approved in the United States. . 145

Figures

FigureNo. Page13. Methods Used to Prepare Subunit Vaccines for Viral Diseases:

Recombinant DNA Technology. Chemical Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . 13814.The Lifecycle of Plasmodum,the Malarial Organism:

Possibilities for Development of Vaccines for Malaria . . . . . . . . . . . . . . . . . . . . . . . . . . 14115.DNA Probe Filter Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

Chapter 5

pharmaceuticals

Introduction

In the United States, many industrial biotech-nology developments rest on the broad base ofknowledge generated by university research inthe biological sciences. Such research has beenfunded largely by the National Institutes of Health(NIH) and other public health-oriented sponsors.As a consequence, the first areas of applicationof new biotechnology in the United States havebeen in the pharmaceutical field. As researchusing the new genetic techniques has progressed,the pharmaceutical industry has been the leaderin industrial applications.

Perhaps the most important application of bio-technology is to facilitate further biomedical re-search. Among the most intriguing areas of re-search using biotechnology are those pertainingto the nervous system, the immune system, theendocrine system, and cancer. As research inthese areas yields insight into mechanisms ofdisease and healthy body function, basic questionsabout the organization and function of the brain,the nature of behavior, and the regulation of bodyfunctions may be answered. The illumination ofthese phenomena, in turn, may generate new pos-sibilities for pharmaceutical products.

Pharmaceutical production may be improvedwith biotechnology in many ways. In some in-stances, production of pharmaceutical productsby chemical synthesis or tissue extraction meth-ods may be replaced by production from clonedgenes. In other instances, applications of recom-binant DNA (rDNA) technology may supplant tra-ditional bioprocess methods for the productionof antibiotics and other pharmaceutical com-pounds. Perhaps most importantly, new biotech-nology provides a means of producing for the firsttime large amounts of compounds that are other-wise scarce. Thus, biotechnology may give riseto the development of entirely new pharmaceu-tical products.

Whatever the intended impact of a new phar-maceutical product, profit expectations usually

govern the selection of projects for development.In considering the use of biotechnology to pro-duce substances by new means, manufacturersmust make multifaceted decisions that include thefollowing considerations:

●

●

●

●

●

●

the possibility of making products superiorto those already marketed for a given pur-pose (i.e., more effective, convenient, safe, oreconomical);the technical feasibility of applying newmethods (e.g., in rDNA applications, the fea-sibility of cloning DNA that directs synthesisof desired substances);the cost of the conventional method (e.g.,chemical synthesis, tissue extraction, or tradi-tional bioprocessing) and the potential to re-duce costs with rDNA technology or othernew methods;the nature of the market (i.e., whether it isof high enough value or volume to justify thesubstantial start up costs of new productionmethodology and regulatory approval);the possible l0SS of production of othersubstances with the change in methods (e.g.,substances that were coproduced in the oldmethod), as well as the potential for develop-ing new, useful byproducts; andthe possibility that the new methods em-ployed will serve as useful models for prepar-ing other compounds (whereby the new tech-nology may justify high startup costs and theloss of formerly coproduced products).

Although biosynthesis may eventually reduce pro-duction costs of widely used compounds by sev-eral orders of magnitude (from millions of dollarsper kilogram for chemical synthesis to severalthousand dollars per kilogram for biosynthesis),chemical synthesis often suffices for productionof low molecular weight compounds for testing,In many cases, substantial research and develop-ment (R&D) costs and high product attrition ratein pharmaceutical development may not justify

119

120 Commercial Biotechnology: An International Analysis

initial exploration of some compounds with bio-technology. .

This chapter introduces the scientific and com-mercial bases of a number of pharmaceuticaldevelopments that exemplify biotechnology’spromise in the pharmaceutical industry. Some ex-amples include human insulin (hI), the first rDNA-manufactured product of biotechnology to reachthe marketplace, interferon (Ifn), human growthhormone (hGH), and human serum albumin (I-ISA)rDNA projects. Other examples discussed aremonoclinal antibodies (MAbs) and DNA hybridi-zation probes, which are already being marketedfor in vitro diagnostic use. Discussions includemarket profiles for each of these compounds,many of which will compete with products madeby other methods.

Several important points are raised in thischapter that are discussed throughout this report.The first is that government regulation and licens-ing of pharmaceuticals play a major part in thedevelopment of these new products. With the rap-id progress taking place in biotechnology, tech-nical barriers may in some instances become sec-ondary to regulatory barriers. Regulatory consid-

Regulatory proteins

The use of biotechnology to manufacture phar-maceutical products can be viewed in severalways. First, biotechnology may be used as asubstitute for conventional methods of produc-tion, which include chemical synthesis and extrac-tion from tissue. The successful cloning projectsand microbial production of the proteins hl, Ifns,and hGH in rDNA systems, outlined below, arevaluable as paradigms for biotechnology’s role indeveloping competitive pharmaceutical substi-tutes, Second, biotechnology may be used to pro-duce unprecedented amounts of scarce biologi-cal compounds, of which certain regulatory pro-teins provide the leading examples. Finally, theuse of biotechnological methods yields basicknowledge on which future research can bebased.

erations that have shaped the use of biotechnol-ogy in the pharmaceutical industry are noted inthis chapter. *

A second point is that in assessing the poten-tial for biotechnology’s use throughout the phar-maceutical industry, it is important to examinethe receptivity of established companies to theadoption of new production methods. Traditional-ly, funding for most of the applied research anddevelopment of new pharmaceutical products inthe United States has been provided by largepharmaceutical manufacturers. Since these manu-facturers generally command the markets forproducts made by conventional means, they mayhave vested interests in established products thatwill impede the development and marketing ofnew products. This situation might perpetuate theproblem of decreasing innovation in the pharma-ceutical industry and contribute to the underde -velopment of biotechnology applications topharmaceuticals.

● For a further discussion of regulatory factors that affect the useof biotechnology in the pharmaceutical and other industrial sec-tors, see Chapter 15: Health, Safety, and Environmental Regulation.

Human insulin

The first therapeutic agent produced by meansof rDNA technology to achieve regulatory ap-proval and market introduction is hI, marketedunder the name Humulin ”. * Although Humu -lin a may be the debutant of rDNA produceddrugs, the extent to which rDNA-produced hI willbe substituted in the marketplace for animal in-sulin is uncertain. Insulin derived from animalshas long been the largest volume peptide hor-mone used in medicine. Human insulin differsonly slightly from that of pigs and cows, and itsincremental benefits have yet to be demonstrated(82).

*Humulin@ has been approved in both the United States and theUnited Kingdom.

Ch. 5—Pharmaceuticals . 121

A profile of insulin markets and sales by Eli Lilly& Co. (U.S. )-the dominant producer and market-er of insulin, and licensee from Genentech Corp.(U. S.) of the new rDNA product–in the UnitedStates and Europe is shown in table 15. By 1985,as indicated in that table, both U.S. and Europeanmarkets for insulin are expected to double. Eli Lil-ly is expected to retain a sizable portion of theU.S. market, but its greatest potential lies inpenetrating foreign markets with Humulin”.

The development and commercialization of Hu-mulin ”establishes several important precedentsof general significance to the introduction of bio-technology to industry:

● Liaison between industry and academic sci-entists. The original bacterial production ofpolypeptide chains of insulin at the new bio-technology firm (NBF)* Genentech made useof nucleic acid sequences synthesized by col-laborators at City of Hope Medical Center, anacademic laboratory that had capabilities nototherwise available to Genentech at the time(31).

● Collaboration between NBFs and establishedcompanies. Early in the development ofHumulin@, Genentech entered a collaborativearrangement with Eli Lilly. Under the agree-ment, Genentech performed the rDNA workand received financial support for the workfrom Lilly. Lilly, in addition to providing thisfinancial support, was responsible for manu-

*NBFs, as defined in Chapter 4: Firms CommercializingBio?echnologv, are firms that have been started up specifically tocapitalize on new biotechnology. Most NBFs are U.S. firms.

Table 15.-U.S. and European Markets for Insulin:Eli Lilly’s Estimated Sales (millions of dollars)

1981 1985 estimate

U.S. market:Lilly’s sales. . . . . . . . . $133 $205’Total market . . . . . . . . $170 $345

●

facturing, marketing, and obtaining regula-tory approval for the hI product that resultedfrom Genentech’s work. This arrangementcapitalized on Lilly’s decades of experiencein large-scale bioprocessing and the purifica-tion of insulin. Most significantly, Lilly wasthoroughly familiar with insulin and the pro-cedures of regulatory agencies, marketing,and distribution. Lilly was able to satisfy theFood and Drug Administration’s (FDA’s) re-quirements for approval of Humulin@ i nrecord time-4 years after the first bacterialpreparation of hI. Under their arrangement,Genentech receives royalties from Lilly onthe sale of Humulin@. Lilly, in turn, has ac-cess to improvement inventions by Genen-tech. Proinsulin, for example, produced fromgenes cloned by Genentech (disclosed inMarch 1980), may provide a more efficientroute for the production of hI or may haveclinical value of its own (see below). This pat-tern of collaboration between NBFs and es-tablished pharmaceutical firms is common. *International joint ventures. Though Eli Lillyhas had little competition in the U.S. insulinmarket until now, the company has been onlya minor factor in insulin markets outside ofthe United States. Recently, however, Lillyhas licensed Swedish and Japanese firms tofacilitate penetration of overseas markets(121). The leading insulin supplier abroad isthe Danish firm Novo Industri A/S (142). Novocountered Lilly’s rDNA hI effort by commer-cializing an enzymatic process devised in theearly 1970’s to transform insulin from swineinto a form identical to hI, * * Novo’s symisyn-thetic hI product was approved for market-ing in the United Kingdom shortly before Lil-ly’s Humulin” attained approval there. Tocompete with Lilly in the United States forinsulin markets, Novo formed a joint venturewith an established American pharmaceuticalcompany, E. R. Squibb (116). Novo also con-

● For a further discussion of collaboration between NBFs andestablished firms, see Chapter 4: Firms Commercializing Biotech-nology.

● ● Hoechst @. R. G.) and Nordisk (Denmark) have subsequently intro-duced semisynthetic M products, and Shionogi (Japan) has developeda significant process improvement involving an immobilized bacterialenzyme (94).

25-561 0 - 84 - 9


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●

tracted with Biogen S.A, (Switzerland)* todevelop an alternative rDNA process for theproduction of hI (11).Refinement of process technology. The raceto supply international insulin markets hasspawned further biotechnological innovationin the pharmaceutical industry. The A andB protein chains of insulin can join in severalways, only one of which is correct. Combin-ing the two chains by nonbiological chemistryis generally regarded as the ‘(hard way” tomake insulin. In the body, a connecting pep-tide in proinsulin (the precursor of insulin)positions the chains appropriately for join-ing to make the biologically active form ofinsulin. The connecting peptide is deletedwhen proinsulin is converted to insulin with-in pancreatic cells. Work to design bioproc-esses using immobilized enzymes** to trans-form rDNA-produced proinsulin into insulinand to separate the products is currentlyunderway. Lilly has reported the productionof human proinsulin in bacteria throughrDNA technology and the efficient conver-sion of proinsulin to hI (27). The NBF Cetus(U. S.) also has an improved proinsulin proc-ess, and Hoechst (l?. R. G.) is reported to bedeveloping one (10).Clarif ication of related problems. The injec-tion of insulin has saved the lives of manydiabetics, but the delivery of insulin by in-jection is thought to cause complications.***Initial hopes for rDNA-produced hI centeredon avoiding allergic reactions to impuritiesin insulin preparations, but these hopes havenot been realized. Although results with pa-tients switching from animal insulin to h.1 areencouraging, substantial allergic responses

“Biogen N. V., the parent company of the Biogen group, is regis-tered in the Netherlands Antilles. Biogen S. A., one of Biogen N.V.’Sfour principal operating subsidiaries, is a Swiss corporation thatconducts R&D under contract with Biogen N.V.

● ● Immobilized enzymes are enzymes bound to solid supports sothat they can exert their catalytic effects on dissolved substanceswithout becoming inextricably mixed up with the reactants andproducts. For further discussion, see Chapter 3: The Technologies.

● ● ● In spite of daily injection of insulin, long-term complicationscontinue to plague many diabetics. After 20 to 30 years of diseasepatients often develop blindness, need for leg amputations, kidneyfailure, stroke, heart disease, and/or nerve damage. About 10 per-cent of all hospital days (21 million per year) are consequences ofdiabetes, and the disease accounts for 19 million physician visitsper year (49).

sometimes occur in patients taking hI for thefirst time (79). These problems probably arisebecause insulin is administered by subcutane-ous injection. Thus, improvements in themode of delivering insulin to patients maybeat least as important to commercial imple-mentation as technical advances in rDNA pro-duction of hI. (See Box B.—Recent Work onDrug Delivery Systems.)

Some diabetic complications may not becaused simply by insulin deficiency. Humanproinsulin, for example, may have therapeu-tic value. Animal proinsulin, which differs sig-nificantly from its human counterpart, is con-sidered a contaminant in preparations of ani- ‘mal insulin. However, some scientists hypoth-esize that administration of human proinsulinmay be beneficial to diabetic patients. Humanproinsulin’s availability through rDNA tech-nology is allowing Eli Lilly to evaluate thishypothesis (27).

Interferon

Ifns, a class of immune regulators or lympho-kines, are proteins that regulate the response ofcells to viral infections and cancer proliferation.These extraordinarily potent substances are thesubject of the most widely publicized, well-fundedapplications of rDNA technology to date, butdetails of their functions remain unknown. Untilrecently, the study of Ifns was limited by the ex-tremely small amounts of Ifn that could be ob-tained from cultured cells. Now, however, rDNAtechnology allows production of large quantitiesof Ifn-like proteins for testing as pharmaceuticalproducts. Despite certain structural differencesfrom native Ifns, * rDNA-produced Ifns appear tohave identical effects on cultured cells.

The cloning and production of Ifns illustrateseveral aspects of the commercialization ofbiotechnology:

● the use of rDNA technology to produce ascarce product in quantities sufficient for re-search on the product’s effects;

. a massive, competitive scale-up campaign by

● Ifns produced by rDNA in bacteria lack carbohydrate (sugar)groups found on native Ifns. It is not known to what extent theabsence of these groups affects protein function.

Ch. 5—Pharmaceuticals ● 123

pharmaceutical manufacturers in advance ofdemonstrated uses of the product;the attempt to produce economically a func-tional glycoprotein (protein with attachedsugar molecules) in an rDNA system;a pattern of international R&D investmentthat reflects the differing needs and medicalpractices of various nations; andthe establishment of a U.S. national effort,via research grants and procurement con-tracts administered through the NationalCancer Institute, the American Cancer Soci-

ety (ACS), and other organizations, to SUppofitesting of Ifns toward a national goal (cureof cancer). *

Ifns are being considered for various pharma-ceutical applications, but are not yet approved as

*In general, Ifn projects in the United States have received massivepublic funding. Studies in Sweden, and to a limited extent in theUnited States, stimulated appropriations of $5.4 million by the non-profit ACS for extended clinical trials in the early 1980’s. This wasby far the greatest single commitment ever made by ACS, and itwas followed by a boost in NIH funding for Ifn research from $7.7million to $19.9 million for fiscal year 1980.

124 ● Commercial Biotechnology: An International Analysis

pharmaceutical products. There is some evidencethat Ifns are effective in preventing certain viralinfections, but more clinical trials are necessaryto demonstrate their preventive abilities (81). *Most evidence that Ifns cure viral infections isanecdotal. In combination with other drugs, how-

*Assuming the safety criterion can be satisfied for the use of Ifnin a prophylactic mode, the immediate market may be for personswhose natural defenses are weakened by illness or medication, suchas those undergoing cancer therapy with drugs or radiation. Otherearly markets could be for patients entering elective surgery or per.sons at high risk of viral exposure, such as teachers and ce~inmedical peraomel. Since Ifns apparently will be available from manysources, the dosage forms or delivery systems may be crucial forwidespread acceptance and efficacy.

ever, Ifns may prove useful in treatment of viraldiseases (50,81,130,157). Extensive clinical trialsto determine Ifns’ effectiveness in the treatmentof herpes and other viral infections are under-way, some which are listed in table 16. The avail-ability of Ifns made with rDNA technology hasallowed many of these clinical trials to be under-taken.

Several clinical trials to evaluate Ifns’ effective-ness in the treatment of cancer have taken place,but, at present, only limited conclusions can bedrawn from the data. In some cases, Ifns inhibittumor cell growth and may stimulate immune

Table 16.—Some Ongoing Clinical Trials Using Alpha or Beta Interferon To Treat Human Viral Diseases

Herpes genitalis

Herpes Iabialis

Herpes infections

Multiple sclerosis

apJIAID- Nation# Institute of Allergy and Infectious Diseases.

%cherlng-Plough’s Ifn produced for clinical trials outside of the United States is synthesized microbially from genes cloned by Blogen S.A.cEnzo Biochem obtained natural alpha-lfn from New York Blood Center and Sponsors trials at Sloan Kettmhrg.

dlnter.y~a LS an Israeli firm conducting clinical trials primarily in Israel, Europa, Md Canda.eGenentech (u.s.) cloned and produces the Ifns being evaluated by Hoffmann-La Roche (Switzerland).f phase H! studies at !jtanford with Ifn obtalnad from K. Cantell, Finnish Red CrOSs, completed In 1~.%egrowth of these wart-like growths, apparently caused by virus, has been Inhibited by Ifns in Danish studies.hNIAID.5ponsored tria15 indicate that Ifn atone la ineff~tlve for the carrier state in males, but combinations with other drugs show prOITliSe.i viral Or{g{n suspected but not PrOv@

SOURCE: Office of Technology Assessment.

Ch. 5—Pharmaceuticals 125

cells to destroy cancerous cells; their effects oninhibiting tumor metastasis are better establishedthan their ability to cause regression of primarytumors (8). With some exceptions, the tumors thatrespond to Ifn treatment (certain Iymphomas,benign human esophageal papillomavirus tumors,and leukemia, in particular) are also the most re-sponsive to established chemotherapeutic agents.Some subtypes of interferon (e.g., alpha-Ifn) oc-casionally induce tumor regression in patientswho are resistant to radiation and multiple drugtherapy (95).

Several problems have been noted in initial clin-ical trials designed to test Ifns’ effectiveness in thetreatment of cancer. For example, side effects(fever, fatigue, and influenza-like symptoms)caused by injections of Ifn made in cell cultureswere thought to be toxic reactions to impuritiesof the culture medium, but pure rDNA-produced1fns show similar side effects (95). Thus, despiteextensive research, numerous questions remainconcerning Ifns’ anticancer potential. Some ongo-ing clinical trials for Ifns’ anticancer propertiesare listed in table 17.

Perhaps the most enlightening results stemmingfrom Ifn research will concern cellular functionduring immune responses. Such results mayprove extremely valuble in medicine. Betterunderstanding of immune mechanisms, for exam-ple, may provide insight into the etiology of therecently problematic acquired immunedeficiencysyndrome (AIDS). Substantial supplies of Ifns toconduct such research can now be produced withrDNA technology.

Though most rDNA-made 1fns currently underevaluation are produced in the bacterium E. ccdi,yeast are being increasingly employed as produc-tion organisms. Yeast require less stringent cul-ture conditions than do most bacteria, have longrecords of reliability and safety in large-scale bio-processing, and are more adaptable to continuousculture production than are many bacteria. Fur-thermore, because yeast more closely resembleshigher organisms than bacteria, yeast can addsugar molecules to protein when necessary. Thus,modified products made in yeast are more likelyto be pharmaceutically useful than unmodifiedproducts made in bacteria. Several groups haverecently reported progress with Ifn production

from yeast, including secretion of the Ifn polypep-tide into the culture medium from which it canmore easily be purified (45). Academic workersfunded by the British firm Celltech, Ltd., have re-ported yields of alpha-Ifn as high as 15 milligrams(3 billion units*) per liter of yeast culture (139).Numerous genetic techniques are being devisedto increase production: 1) amplification of thenumber of Ifn genes, 2) enhancement of gene ex-pression by placing it under control of regulatoryelements which can be varied without hamper-ing cell growth, 3) limitation of product degrada-tion, 4) inducement of product secretion, and 5)stabilization of microbial strains. Additionally, theSwiss company Hoffmann-La Roche has reporteda MAb system for alpha-Ifn purification that givesin excess of 1)OOO-fold purification with 95 per-cent recovery of biological activity (133).

Many U.S. and foreign companies using biotech-nology are working toward large-scale Ifn pro-duction. Some of the companies with Ifn genecloning projects are listed in table 18. The largenumber of companies involved in Ifn productionreflects the large market potential so widelypublicized in the late 1970’s. Since clinical trialshave not supported many of the claims made forIfns, companies are beginning to draw back fromIfn R&D.

The international pattern of interest and invest-ment in the use of rDNA technology to produceIfn reflects to some extent international differ-ences in medicine and, possibly, movements toreduce national dependence on pharmaceuticalimports. Japan, for instance, has long been thelargest market in the world for cancer drugs, to-day exceeding $375 million in annual sales (com-pared to $210 million in the United States) (127),and is actively investigating the production of anti-cancer pharmaceutical products using new bio-technology. * *

*A single dose of Ifn ranges from 1 million to 100 million units.* *protein agents are especially popular for cancer treatment in

Japan. 1mmunotherapeutic concepts which are regarded as ex-perimental hypotheses in the West provide the rationale for admin-istration in Japan of hundreds of mdhons of dollars worth of agents,such as Krestin” (an orally administered fungal glycoprotein thataccounted for Japanese sales in 1981 of $230 million) and urokinase(which is used in Japan for indications not even suggested in theUnited States). Sales of over $117 million were recorded in 1981for a streptococcial “vaccine,” czdlwl Picibanil@, which Japanese physi-cians regard as an immunostimulant (118).

126 . Commercial Biotechnology: An International Analysis

Table 17.—Some Ongoing Clinical Trials of the Use of Interferon To Treat Cancer

s-P

s-P

s-P

s-P

University of Wisconsin


Table 17.–Some Ongoing Clinical Trials of the Use of Interferon To Treat Cancer (Continued)

Interferon supplier Sponsor Cancer Phase Institution

Osteogenic sarcomaBreast cancer

IIII

IIII

Antibodies)” memorandum, May 4, 1983.

Human growth hormone

As suggested by the preceding discussion, rDNAtechnology is increasingly being used to producelarge amounts of otherwise scarce biological com-pounds. In addition to supplying compounds forbasic research, rDNA technology is likely to con-tribute to the discovery of many new pharmaceu-tical products. Some of the promising proteincompounds actively being developed with rDNAtechnology-human growth regulators, neuro-active peptides, and lymphokines, for instance—are listed in table 19.

The development of hGH with rDNA methodsis another model for biotechnology’s use in thepharmaceutical industry. Human growth hor-mone is one of a family of at least three, closelyrelated, large peptide hormones secreted by thepituitary gland. These peptide hormones areabout four times larger than insulin (191 to 198amino acids in length). All three hormones possessa wider variety of biological actions than do mostother hormones. The primary function of hGHis apparently the control of postnatal growth inhumans. Whereas insulin derived from slaught-ered animals can be used for treating diabetics,only growth hormone derived from humans issatisfactory for reversing the deficiencies ofhypopituitarism in children (65).

Although the established market for hGH issmall and current supplies from tissue extracts

are sufficient, * hGH was one of the first targetsfor the applications of rDNA technology. Workersat both Genentech and the University of Califor-nia, San Francisco (UCSF) reported cloning andexpression of hGH in 1979 (39). Genentech’s workwas supported by the Swedish firm KabiGen AB,while partial funding for the UCSF work was pro-vided by Eli Lilly, which is believed to be thelicensee for the product (39). Genentech has suchhigh aspirations of proving sufficient utility forhGH in medical applications beyond those cur-rently treated with cadaver hGH that it has an-nounced its intent to make the development ofhGH from rDNA one of the cornerstones of itsintegrated pharmaceutical enterprise (9). To thisend, Genentech is raising capital through an R&Dlimited partnership specifically to support clinicaltesting of hGH and is investigating a variety ofpossible new clinical indications for hGH use, TheNIH National Pituitary Agency has been enthusi-astic about these investigations, which were notpractical when the supply of hGH was limited bythe availability of human cadaver pituitaries (104).

● Most pharmaceutical hGH ia obtained from human pituitariesremoved at autopsy. In the United States, isolation and distributionof hGH has been managed primarily by the National Pituitary Agency(under the auspices of NIH and with the cooperation of the Collegeof Pathologists). Under pmgrama of the National Institute of Arthritis,Diabetes, and Digestive and Kidney Diseases, hGH is provided,without charge, for approximately 1,600 children per year for treat-ment of hypopituitariam. Another several hundred patients aretreated with commercial hGH imported from abroad, which is alsoobtained from tissue extracts (39).


Table 18.—Some U.S. and Foreign Companiesinvoived in interferon Gene Cioning Projects

‘%his alpha4fn lacks carbohydrate groups, but lack of glycosylatlon does notappear to influence activity.

bAttemptlng production In yeast.Cclinical trials began early ‘n ‘m”%oray is seating-up to acapmity of 3- 101* units par month and expects approval

from Japan’s Ministry of Health and Welfare soon for beta-lfn as an anticancer

e&unge~{2~\ retdnti ~1 mmufwtuhng rights and only licensed Its Japanew col-

f Iaborators to sell in Japan and, parhaps, other Asian markets (32).Revlon’s subsidiary, Meloy Laboratories was the first firm to supply both alpha-Ifn and gamma-lfn to the National Cancer Institute.

%slng Genentech’s published gamma.lfn gene sequence (450 bases long),Suntory, a Japanese beverage company, took only 3 months to synthesize andclone the gamma-lfn gene (1 19). Suntory has also succeeded in producinggamma-lfn in yeast.

SOURCE: Office of Technology Assessment; and S. Panem, The Interferon Cru-sade: Public Policy and Biomedical Dreams, Brooklngs Institution,Washington, D.C., {n press.

KabiVitrum AB, a firm owned by the SwedishGovernment, is the world’s largest producer ofhGH from frozen human pituitaries (113). Kabi-Vitrum owns 50 percent of KabiGen AB, whichhas the sole rights to manufacture and markethGH made by the Genentech process anywhere

in the world, except in the United States andCanada, where Genentech has sole rights (31).KabiGen researchers are among the long-termleaders in the study of other growth-promotinghormones, especially the polypeptides known assomatomedins (30,100).

Although it is premature to judge the likelihoodof success, hGH is being evaluated for: 1) treatingconstitutionally delayed short stature; 2) improv-ing healing of burns, wounds, and bone fractures;and 3) treating the deficiency of nitrogen assimila-tion known as cachexia (9). Approximately 3 per-cent of all children are thought to have constitu-tionally delayed short stature, and Genentech ad-visors speculate that as many as one-third of thesemight benefit from hGH treatment (136). *

Neuroactive peptides

Several important biosynthetic discoveries in re-cent years have involved identification of polypep-tides in the body that act at the same cellular re-ceptors that are affected by drugs. Some of thebody’s neuroactive peptides, for example, bind tothe same receptors affected by opiate drugs andproduce analgesic effects in the nervous systemsimilar to those produced by these drugs. Twoof the body’s own “opiates,” enkephalins and en-dorphins, appear to be structurally related tomany other polypeptides that play various rolesin the nervous and endocrine (hormonal) systems(41). Another neuroactive peptide that may affectneurological processes, including attention span,is melanocyte stimulating hormone (MSH). Someevidence suggests that MSH enhances the abilityof test animals to pay attention to their environ-ment, and MSH treatment has improved thehealth of some mentally retarded patients as well(53). Initial hopes raised by the treatment ofschizophrenic patients with beta+ndorphin havenot withstood more rigorous testing. Results oftesting some other peptides as antidepressants,after encouraging earlier studies, are also disap-pointing (53).

● Genentech, Lilly, Amgen, Monsanto, and other firms are also in-terested in applications of rDNA-produced GHs for food produc-tion purposes, and those investigations may prove complementaryto the medically oriented studies (see Chapfer 6: Agriculture).


Table 19.—Some Proteins With Possible Pharmaceutical ApplicationsBeing Developed With Recombinant DNA Technology

Size(numberof amino

Class/substance acids) Function R&D status Project sponsors Applications

synthesized, 1982


Despite the setbacks noted above, many inves-tigators are confident that neuroactive peptidesare among the most promising potential advancesin medicine; thus, a great deal of research is be-ing done on synthetic analogs of neuroactive pep-tides (e.g., 26,41) to identify structures that mayhave research or pharmaceutical applications. Lil-ly and Burroughs-Wellcome (U.K.) are investigat-ing the use of enkephalin analogs in clinical trialsin the United States. Foreign companies with ma-jor research programs concerning neuroactivepeptides include Abello @. R.G.), Hoechst (F.R.G.),Hoffmann-La Roche (Switzerland), Organon (Neth-erlands), Reckitt & Colman (U.K.), Roussel Uclaf(France), Sandoz (Switzerland), and Takeda(Japan). In addition to screening neuroactive pep-tides compounds for analgesic and anesthetic ac-tivity, researcher~ are attempting to recognizethose compounds that might suppress coughingor diarrhea or might counteract asthenia, cerebralvascular disorders, failing memory, mental de-pression, Pmkinson’s disease, and forms of de-mentia, including senility.

Much basic research remains to be done beforesubstantial use is made of neuroactive peptidesas pharmaceutical compounds in medicine (53).Studies of these substances and their chemicalanalogs are expected to result in the developmentof new drugs, some of which may be producedwith biotechnology, Companies vigorously pur-suing the production of neuroactive peptides withbiotechnology include Amgen (U.S.), which hascloned and obtained expression of the genes for

the neuroactive peptide betaadorphin (126), andEndorphin, Inc. (U.S.), which is primarily con-cerned with compounds active in both the nerv-ous and digestive systems.

Lymphokines

Lymphokines are proteins produced by lym-phocytes (cells of the immune system) that con-vey information among lymphocytes. With the ex-ception of Ifn, lymphokines are only beginningto be characterized, but these proteins appear tobe crucial to immune reactions. Some lympho-cytes, for example, produce lymphokines thatengage other lymphocytes to boost the immuneresponse to a foreign substance (antigen) andrepel foreign invasion or disease. Other lympho-cytes produce lymphokines that act in tandemwith the antigen to stimulate the secretion of an-tibodies. Lymphokines may also help to ensurethat only the antigen is attacked during an im-mune response, not the body’s own tissues.

The importance of lymphokines in preventingdisease and understanding cellular function (in-cluding aberrant cell function such as cancergrowth) is fostering widespread research on thesecompounds (for review, see 47). Investigations ofthe complex interactions among lymphocyteshave been hampered in the past by impure lym-phokine preparations, which have led to ambig-uous findings. Recent progress, including theestablishment of lymphocyte cell lines that pro-duce various classes of lymphokines (e.g., 37) and

Ch. 5—Pharmnaceuticals ● 131

cloning of lymphokine-producing genes into rDNAsystems for production in bacteria (24,137), hasbeen made possible with the use of biotechnology.The availability of pure lymphokine samples fromsuch systems may enable researchers to answermore questions concerning cell biology and im-mune function. Lymphokines may also be usefulin the culture of certain cell lines. Eventually,these efforts may lead to the use of lymphokinesin medicine to stimulate the patient’s own immunesystem to combat disease.

Leading commercial efforts to produce lympho-kines with biotechnology are centered in Japan,Switzerland, and the United States. In Tokyo, Dr.Tadatsugi Taniguchi of the Japanese Cancer In-stitute is collaborating with Ajinomoto Companyto produce the lymphocyte growth factor, inter-leukin-2 (13). IN Switzerland and the United States,numerous firms using biotechnology are engagedin lymphokine research, especially in the produc-tion of interleukin-2, but their efforts are largelyproprietary at this time (24).

Other regulatory proteins

In addition to hormones and other regulatoryproteins, a number of protein “growth factors”for a variety of somatic (body) cells have beenisolated and are currently being characterizedwith the possibility that they may soon be can-didates for production by rDNA technology aswell (see table 20). Perhaps the most importantuse of growth factors will be in preparing culturemedia for growing higher eukaryotic cells, there-by facilitating further research with more com-plex cells.

Table 20.-Some Protein “Growth Factors” WithPotential Pharmaceutical Applications

Factor Function

CSF (colony stimulatingfactor) . . . . . . . . . . . . . . . .

ECGS (endothelial cellgrowth supplement) . . . .

EDGF (endothelial-derivedgrowth factor). . . . . . . . . .

EGF (epidermal growthfactor) . . . . . . . . . . . . . . . .

FGF (fibroblast growthfactor) . . . . . . . . . . . . . . . .

FN (fibronectin) . . . . . . . . . .

MDGF (macrophage-derived growth factor). . .

NGF (nerve growth factor) .

PDGF (platelet-derivedgrowth factor). . . . . . . . . .

SGF (skeletal growthfactor) . . . . . . . . . . . . . . . .

WAF (wound angiogenesisfactor) . . . . . . . . . . . . . . . .

TAF (tumor angiogenesisfactor) . . . . . . . . . . . . . . . .

Stimulate granulocytedifferentiation

Required by vascular liningcells

Stimulates cell division inblood vessels

Stimulates growth ofepidermal cells andmany tumors

Stimulates fibroblast cellgrowth

Stimulates adhesion andproliferation of fibroblastcells

Stimulates cell divisionnear inflammation

Stimulates nerve growthand repair

Stimulates division offibroblast-like cells

Stimulates bone cellgrowth

Stimulates wound healing

Stimulates blood vesselproliferation in tumors

SOURCE: Office of Technology Assessment, 19S3.

Blood products

Products derived from the fractionation of hu - three main plasma commodities are human serumman blood represent the greatest volume of bio- albumin (HSA), gamma globulin (GG), and anti-logical pharmaceutical products sold today and hemophilia factor (AHF), which accounted for 41comprise a world market of $1 billion yearly. The percent, 25 percent, and 13 percent, respective-


ly, of the global plasma component market in1978. North America and Japan each consume 25percent of the world’s blood products (106).

The United States now enjoys a favorable tradebalance with respect to blood products. Becauseblood donation is more widely practiced in theUnited States than elsewhere, the United Statessupplies blood components to many other coun-tries. Japan obtains 50 percent of its HSA and 60percent of its GG* from the United States. Theplasma production of Europe is about 60 percentof that of the United States (105).

The blood products industry is characterizedby large markets and strong incentives for bio-technological innovation on a nationwide basis.Currently, the industry is troubled by the diseaseAIDS. Although the etiology of AIDS is not yetunderstood, the strong possibility that it can betransmitted in blood products lowers the market-ability of such products. Thus, the industry isseeking new methods for the production of bloodproducts. * *

Human serum albumin

HSA, a single polypeptide chain of 585 aminoacids, is the protein used in the largest quantities

● GG is a fraction of serum that contains antibodies. Soosting apatient’s antibody level generally is thought to help prevent infec-tious disease. This treatment is used especiaUy for hepatitis preven-tion. The ability to produce specific antibodies (MAbs) may makeGG a less desirable therapy and increase the effectiveness of an-tibody prophylaxis.

* “These efforts are to be discussed in a forthcoming OTA report,Blood Banking Policy and Technology..

in medicine. HSA is used primarily during surgeryand to treat shock, burns, and other physicaltrauma. In 1979, worldwide HSA consumption ex-ceeded 90,000 kg, with U.S. consumption account-ing for 80 percent (72,500 kg) of this amount. Al-though the United States consumed large amountsof HSA relative to most other countries in the past,foreign HSA consumption is rising, as shown intable 21. Worldwide HSA consumption is ex-pected to exceed 250,000 kg by 1984 (64,106,143)with the largest increases of HSA consumptiontaking place in foreign countries. The UnitedStates has experienced an overcapacity of HSAproduction from blood fractionation since 1975(143) and is currently the world’s leading exporterof HSA.

HSA’S tremendous markets make it an attrac-tive target for production with biotechnology.However, HSA’S substantial molecular size (585amino acids) and its relatively low cost of conven-tional production present formidable challengesto biotechnology. In November 1981, Genentechamounced successful HSA production in bacteriaand yeast through rDNA manipulation (63). Thisachievement is a landmark in several respects:

●

●

●

HSA is the largest protein (585 amino acids)yet produced by rDNA technology.Planners and technologists aim to manufac-ture tons rather than grams of injectableproducts using rDNA systems.Competitive product costs are more than anorder of magnitude lower per unit weight ofproduct than those for previously consideredrDNA pharmaceuticals (e.g., less than $1/

Table 21 .—Human Serum Albumin Production and Consumption in the United States

Forecast1971 1976 1979 1984

Plasma processed in the United States (thousands of liters) . . . . . . 1,950 2,910 3,950 6,920HSA production in the United States (millions of grams) . . . . . . . . . 39 67 91 159HSA consumption:

Domestic (millions of units) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9 4.6 5.8 8.5Foreign (millions of units) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 0.7 1.5 4.2

Total (millions of units) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 5.3 7.3 12.7Domestic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 940/0 870/o 800/0 670/oForeign . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60/0 13’?/0 200!0 330!0

HSA revenues:Domestic (millions of dollars) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $58 $133.4 $168.2 $300Foreign (millions of dollars) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.3 43.5 148Total (millions of dollars) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . : 2 153.7 211.7 448

SOURCE: Office of Technology Assessment, based on data and estimates in M. M. LeConey, “Who Needs Plasma?” Plasrrra C?uar?edy 2:66-93, Septembr 1960.


gram, compared to somewhat less then $50/gram for insulin).

● The companies that successfully produceHSA with rDNA technology will amass knowl-edge of certain related processes, includingpurification of large amounts of product. Thisknowledge might allow them to dominate theproduction of other proteins made by similarprocesses.

Since cloning the HSA gene, Genentech has en-tered into an agreement with Mitsubishi ChemicalIndustries, Ltd. (Japan) to cooperate in continuedR&D for manufacturing and commercialization.The partnership hopes to produce 10 metric tons(tonnes) of HSA per year by 1985 (121). Mitsubishiwill probably ask Green Cross, which is the largestJapanese blood products company, to distributethe rDNA-produced product, thus avoiding dis-crimination against the present distributor ofHSA. In 1981, HSA sales in Japan were $60 million(*14.2 billion) (118), compared to about $200million in the United States (64). The corporatearrangements between Genentech, Mitsubishi,and Green Cross may lead to the reduction ofJapanese imports, the establishment of a bloodproduct industry in Japan, and advances in Jap-anese technology for producing and purifyingproteins.

Genex (U. S.) and Biogen S.A, (Switzerland) alsohave established arrangements with Japanesefirms to conduct R&D on rDNA production ofHSA (115). Genex made a contract in 1981 withGreen Cross. In exchange for research funding,Genex agreed to grant Green Cross exclusivelicenses to make, use, and sell all microbially pro-

duced HSA developed under the contract in theFar East, South America, and North America.Genex made a similar agreement with the Swed-ish firm KabiVitrum, with licensing pertaining toEurope, Africa, and the Middle East. Biogen S.A.negotiated a similar agreement in late 1981 tocooperate with Shionogi (Japan) in the develop-ment of rDNA techniques for HSA production.

Only one major American drug company, Up-john Pharmaceuticals, shows evidence of develop-ing a fully in-house large-scale biosynthetic HSAprocess. Upjohn is making HSA in both E. coli andyeast.

Antihemophilic factor

AHF, a class of proteins contained in the frac-tion of blood used to treat hemophilia (a set ofhereditary disorders that prevent blood clotting),is used by approximately 14)000 hemophiliacs inthe United States on a routine basis (143). TypeA hemophilia, which affects about 5 people inevery 100,000, is caused by a deficiency of fac-tor VIII, and type B hemophilia (which is muchrarer but equally severe) by a lack of factor IX.

AHF is separated during the fractionation ofwhole blood to obtain HSA, As shown in table 22,U.S. AHF production has multiplied faster thanconsumption in recent years, and AHF comprisessizable exports for U.S. firms and nonprofitorganizations. With AHF selling for over $1 mil-lion per gram and AHF use growing at a rate of14 percent per year, AHF is the blood fractiona-tion industry’s most profitable product (64).

Table 22.—Antlhemophilic Factor Production and Consumption in the World

Forecast1971 1976 1979 1984

Plasma processed globally for AHF (thousands of liters) . . . . . . . . . 365 1,600 2,750 5,320AHF units processed (millions). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 400 688 1,330Domestic consumption:

Millions of units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 300 412 648Average price (cents/unit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 10 10 14Sales (millions of dollars) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.8 30 41.2 91

Foreign consumption:Millions of units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 100 275 682Average price (cents/unit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 30 30 27Sales (millions of dollars) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 30 82.5 184

Total AHF sales (million of dollars) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 60 123.9 275

SOURCE: Office of Technology Assessment, based on data and estimates in M. M. Le Coney, “Who Needs Plasma?” Plasma Ouarterfy 2:68-93, September 19S0.


Efforts to produce AHF with biotechnology areunderway. The gene for factor IX has recentlybeen cloned and expressed in E. coli (18,61). Theavailability of factor IX produced by rDNA tech-nology facilitates studies concerning the geneticbasis of type B hemophilia (e.g., 35). However,quantities of factor IX necessary to treat the rela-tively uncommon type B hemophilia are adequate-ly provided by whole blood fractionation, and therDNA product is not now a competing alternative.

Significantly stronger medical and commercialreasons motivate efforts to clone factor VIII genes,since the majority of hemophiliacs are type A. Atpresent, difficult problems surround factor VIIIgene cloning. Not only is factor VIII present inlow concentrations in plasma, making its isolationand purification difficult, but this molecule is anextremely large and labile glycoprotein (over300,000 molecular weight, about 20 times the sizeof Ifn). Recent progress in factor VIII research in-cludes development of MAbs to aid in AHF isola-tion (86,132) and localization of AHF-producingcells in the liver (134).

The rDNA production of factor VIII is an elusivegoal, but the implications of success are substan-tial. Apart from providing more economic treat-ment for hemophiliacs, results of factor VIII clon-ing may lead to a better understanding of themost common type of hemophilia and prove use-ful for prenatal screening for the disease.

Biosynthetic AHF may lower costs of treatmentfor the expanding population of hemophiliacsthroughout the world. Furthermore, if the pro-duction of HSA from rDNA technology provescompetitive with fractionation, the need to pro-duce AHF with rDNA may be paramount, sinceAHF is copurified with HSA from plasma. *

Research laboratories working towards AHF mi-crobial biosynthesis include the following (12,128):

● Armour Pharmaceutical (U. S.)/Scripps Clinicand Research Foundation (U.S.),

● The price of factor VIII controls the price of serum albumin (64).The worldwide growth rate for AHF, about 14 percent per year(64), is twice the growth rate of HSA. Thus, any major shift of HSAproduction to rDNA technolo~ with a concomitant loss of AHF pro-duction may drive the price of AHF (produced from fractionation)to higher levels.

●

●

●

●

Baxter Travenol Laboratories (LJ.S.)/GeneticsInstitute (U.S.),Biogen S.A. (Switzerland)fleijin (Japan),Speywood Laboratories (U.K.)/Katherine Dor-mandy Hemophilia Centre and the Royal FreeHospital of London (U.K. )/Genentech (U.S.),andConnaught Laboratories (Canada)/CanadianGovernment.

Thrombolytic and fibrinolyticenzymes

Thrombosis, the blockage of blood vessels, isthe leading cause of death in industrialized na-tions. Blood clots in the vessels that supply theheart (coronary heart disease), brain (stroke), orlungs (pulmonary embolism) account for morethan half of all deaths in the Western Hemisphere.

The search for substances that dissolve bloodclots is a major undertaking of the pharmaceuticalindustry. At present, the most popular com-pounds are thrombolytic and fibrinolytic en-zymes. These substances initiate the dissolutionprocess by converting plasminogen, a plasma pro-tein, into plasmin, which then attacks fibrin, theprotein that comprises most of the blood clot.

The two most widely used thrombolytic en-zymes are streptokinase and urokinase. Strep-tokinase is manufactured from colonies of Strep-tomyces bacteria, while urokinase is obtainedeither from cultured human kidney tissue or fromhuman urine. Recent improvements in large~calecell culture techniques and purification methods(including the use of MAbs for the purificationof protein) now yield good quantities of throm-bolytic enzymes (57). Despite the great usefulnessof these enzymes, however, several problemsdiminish their clinical value. In prolonged therapywith streptokinase, chances of allergic reactionsarise. In addition, streptokinase and urokinase ap-pear to act nonspecifically throughout the body,thus raising risks of internal hemorrhaging in pa-tients. To circumvent this risk, carefully placedcatheters must be used to deliver the enzyme toits target. Finally, high costs of manufacturing andtherapy also restrain more widespread use (strep-tokinase treatment costs $275, while urokinasecosts about $3,000 per patient) (57). Because of


these problems, alternative thrombolytic enzymesand more economic production methods are be-ing sought.

A group of fibrinolytic enzymes called tissueplasminogen activators (tPAs) may solve some ofthe problems associated with streptokinase andurokinase. Although tPAs are generally not wellcharacterized and are only available in limitedquantities at present, they appear to work specif-ically at blood clots over a prolonged time (59),reducing both the risks of hemorrhage and thedoses necessary for thrornboiysis, thus loweringcosts of treatment.

Advances in culturing tPA-secreting cells andisolating tPA using MAbs indicate that manufac-turing costs may be reduced in the future. More-over, Genentech, in collaboration with investiga-tors at the University of Lueven (Belgium), recent-ly succeeded in cloning the gene that producestPA (108), and a number of other companies areworking to produce tPA from rDNA systems (seetable 23). Cloned genes in bacteria or yeast mayprovide a means for economically producing largequantities of tPA. The biochemical effectivenessand commercial viability of rDNA-produced tPAsremain to be demonstrated. In particular, ques-tions concerning the stability of the cloned genesin bacterial strains, scale-up costs, and importance

of sugar residues found on native tPA remain tobe answered.

At present, the extent to which thrombolyticenzymes are used by different countries variessubstantially. German and Japanese physiciansprescribe streptokinase and urokinase extensive-ly, often in conjunction with cancer chemother-apy (on the premise that fibrin shields tumorsfrom drugs and the body’s immune defenses andhence must be removed). American medical prac-tices, on the other hand, discourage the use ofstreptokinase and urokinase because of the prob-lems mentioned earlier. Thus, the annual marketfor thrombolytic enzymes in the United Statesrepresents a modest $8 million, whereas the an-nual market for urokinase in Japan, where it isthe seventh largest selling drug, represents $150million (57).

The widespread sponsorship of tPA projects byJapanese companies, as shown in table 23, reflectsthese national differences in thrombolytic enzymeuse. In addition to underwriting clinical testingand marketing costs of enzymes produced fromcultured cells, Japanese companies such as GreenCross are active in sponsoring tPA productionusing rDNA techniques.

The development of tPA illustrates biotechnolo-gy’s role in providing new pharmaceutical agents.

Table 23.-Thrombolytic and Fibrinolytic Enzymes: Companies Involved in Development and Marketing

Protein Company Project description

Streptokinase . . . . . . . . . . . . . Hoechst-Roussel (F. R. G.) Production from bacteriaKabiVitrum (Sweden) Production from bacteria

Urokinase . . . . . . . . . . . . . . . . Abbott Laboratories (U. S.) Extraction from cultured kidney cellsGenex (U. S.)lMitsui Toatsu Chemicals, Inc. Production from rDNA

(Japan)Genentech (U. S.)/Grunenthal (F. R.G.) Production from rDNA

Human tissue plasminogenactivator . . . . . . . . . . . . . . . . GenentechlUniversity of Leuven (Belgium)l Production from rDNA

Mitsubishi Chemical Industries, Inc.(Japan)lKyowa Hakko Kogyo (Japan)

Biogen S.A. (Switz.)lFujtsawa (Japan) Production from rDNAIntegrated Genetics (U.S,)I Production from rDNA

Toyobo Pharmaceutical (Japan)Chiron (U. S.) Production from rDNACollaborative Resarch (U.S.)/ Extraction from cultured kidney cells

Green Cross (Japan)Anticoagulant and

fibrinolytic agents ., . . . . . Genentech/Yamanouchi Ltd. (Japan) Development of microbial strains thatGenex/Yamanouchi Ltd. produce a fibrinolytic agent



Through the use of improved bioprocess systems, Given successful economic development of tPApurification methods, and rDNA technology, large (i.e., at one-half the cost of urokinase production)quantities of scarce materials are becoming avail- and improved mode of action, industry expertsable for study, possibly leading to substantial estimate that U.S. markets for tPA could climbchanges in medical practices in the United States. swiftly to $125 million per year (57).

Vaccines

The combined techniques of biotechnology findperhaps no greater promise for medicine than inthe preparation of vaccines and other pharmaceu-tical products to combat infectious diseases. Thereare several approaches to disease control usingbiotechnology, including the use of rDNA andMAb technology, artificial vaccine synthesis, andprotoplasm fusion to prepare novel antibiotics.

Most vaccines used at present consist of the or-ganisms that cause the particular disease that thevaccine is intended to prevent. These organisms(pathogens) are killed or otherwise treated (’(at-tenuated”) in an effort to make them nonvirulent,and the killed or attenuated mixture is then in-jected into the person to be vaccinated. Ideally,the recipient’s immune system responds to theintroduction of the vaccine by producing anti-bodies that bind to particular molecules (antigens)on the surface of the vaccine organism and iden-tifying it for destruction by other components ofthe immune system. The antibodies produced bythe recipient remain in circulation for a periodof months to years, protecting the recipientagainst the live pathogen should it be encounteredlater. Thus, the recipient becomes “immune” tothe disease. Immunity thus induced, since it usesthe recipient’s immune system for constant sur-veillance and defense against the disease, isknown as “active immunity.” The administrationof foreign antibodies or immune products thatthemselves protect the recipient from the disease,on the other hand, provides what is known as“passive immunity.” Passive immunization usuallyconfers only short-term protection against a dis-ease.

Killed and attenuated vaccines represent oneof the highest achievements in medicine. Never-theless, several problems with these vaccines per-sist. one substantial problem is that killed and at-

tenuated vaccines contain the complete geneticmaterial of the pathogen, If the pathogen is notkilled or attenuated completely, the vaccine itselfmay be capable of causing the disease it is in-tended to prevent. Another problem with conven-tional vaccines is that, in many instances, they donot immunize the recipient against all of the var-ious strains of the pathogen. Finally, many con-ventional vaccines are not stable enough for usewhere they may be most needed, as in areas with-out refrigeration.

Subunit vaccines—vaccines that contain onlyportions of the pathogens-may solve some of theproblems associated with killed and attenuatedvaccines. Subunit vaccines do not contain thepathogen’s genetic material, and, thus, they can-not themselves cause infection. Furthermore, sub-unit vaccines may be more stable for storage andof greater purity than most conventional vaccines,although these qualities remain to be demon-strated in most cases. Two new methods are be-ing developed to prepare subunit vaccines: rDNAtechnology to produce all or part of a surface pro-tein molecule of the pathogen and chemical syn-thesis of short polypeptides that represent sur-face proteins. Both of these new approaches havethe added advantage that subunit vaccine manu-facture does not require large-scale culture of theinfectious organism.

Viral disease vaccines

Because of the relatively simple, well-under-stood structure of viruses, the most preeminentbiotechnology efforts for the development of newvaccines are focused on viral diseases (51,135).As shown in table 24, biotechnology is being usedto develop vaccines for influenza types A and B,herpes, polio, hepatitis A and B, and a number


Table 24.—Some Current Viral Vaccine Biotechnology Projects

Viral disease Company Project description

Influenza virus. . . . . .

Polio virus . . . . . . . . .

Hepatitis B virus. . . .

Herpes viruses . . . . .

Numerous investigatorsNumerous investigators

Scripps (U. S.)

Scripps

Numerous investigators

Merck (U. S.)lnstitut Pasteur Production (France)Chiron Corp (U. S.)lMerck/University of

Washington, UCSFTakeda/Osaka and Hiroshima Universities

(Japan)Amgen (US.)Biogen/Green Cross (Japan)Wniversity of

EdinburghIntegrated Genetics (U. S.)lConnaught (Canada)Merck

Molecular Genetics (U. S.)lLederle Labs (U. S.)Institut Merieux (France)Wniversity of Chicago


of other human viral diseases. The two mainmethods used to prepare subunit vaccines forviral diseases are summarized in figure 13.

Hepatitis B subunit vaccines, in particular, il-lustrate the use of biotechnology in vaccine im-provement. Using the rDNA approach, a numberof groups have cloned genes that encode portionsof the hepatitis B surface antigen (HBsAg) andhave shown that isolated surface antigens behavesimilarly to the whole virus when used as a vac-cine (25,74,131,146). Merck (U.S.), which supportswork done at UCSF and Chiron Corp. (U. S.) andhas built an in-house molecular genetics groupof nearly 50 scientists since 1978, expects to mar-ket a hepatitis B vaccine made from rDNA in yeastby 1987 (44). Biogen S.A. (Switzerland) has suc-cessfully immunized chimpanzees against hepa-titis B using its yeast-grown vaccine, and a licenseto Biogen’s work with hepatitis vaccines has beenacquired by Green Cross (Japan). It has been es-timated that Biogen’s hepatitis B vaccine will sellfor only $10 to $30 per dose as compared with$100 per dose for Merck’s vaccine made fromvirus particles extracted from blood of hepatitisB carriers (14,71). How well these rDNA-producedhepatitis B subunit vaccines will compete with

Improved attenuated strainsModifications of viral genome through rDNA

manipulationsSynthesis of short peptides corresponding to

fragments of influenza virus surfaceproteins

Attachment of viral subunit to larger carrierto evoke broader immune response

Modifications of viral genome through rDNAmanipulations

Purification of viral particles from blood

Production of viral surface proteins fromrDNA in yeast

Purification of surface glycoprotein fromherpes simplex viruses

Production of viral proteins in bacteriaProduction of nonpathogenic viruses by the

deletion of specific genes

vaccines made by traditional methods is not yetknown, but the need for an effective and inexpen-sive hepatitis B vaccine is great. *

Using chemical synthesis, other researchershave prepared synthetic polypeptides which maybe useful as subunit vaccines. These syntheticpeptides are based on known amino acid se-quences of virus surface proteins. The amino acidsequences and their molecular shapes are ana-lyzed by computer, and peptide sequences thatare likely to elicit immune responses are defined(for review, see 68)). Researchers have synthe-

● In the United States, there are 80,000 to 100,000 cases of hepatitisB and about 1,000 deaths each year. The incidence in some otherparts of the world runs 10 times as high. Between 3 and 15 per-cent of healthy blood donors in Western Europe and the UnitedStates show serological evidence of past infection, and 0.1 percentare chronic carriers of the type B virus. In many African and Asiancountries the majority of the adult population have been infected,and 5 to 10 percent of the population are clinically ill with hepatitis.A very strong association has recently been demonstrated betweenthe carrier state of hepatitis and liver cancer. In areas of the worldwhere hepatitis B is endemic, primary liver tumors account for 20percent of cancer, in contrast to the 1 percent level of liver tumorincidence in the United States (150). A costly hepatitis B vaccine wasbrought to market by Merck in 1982 in the United States. Althoughnot made with new biotechnolo~v, this vaccine consists of naturalsubunits—particles of the virus coat protein which are isolated andpurified from the blood of relatively rare suitable donors (34,44).

25-561 0 - 84 - 10


Figure 13.—Methods Used to Prepare Subunit Vaccines for Viral Diseases:Recombinant DNA Technology v. Chemical Synthesis

Chemical Synthesis Method

/

synthesize thesurface protein gene

Extractprotein vaccine

IIn the chemlcal synthesis method, proteins that comprise the viral surface are Isolated, often with the use of monoclinal antibodies. The protein sequence is thendetermined. Based on the sequencing information, large amounts of the Protein or Portions of the Protein are made chemically for use as the vaccine; alternatively, thesequencing information may allow chemical synthesis of the gene that encodes the protein (or a small portion of the protein). This synthetic gene is cloned wa rDNAtechniques.In the recombinant DNA method, the gene that encodes the viral surface Protein is Isolated and cloned into an appropriate vector (such as Plasmid), transformed into ahost (such as a bacterium or yeast), and the host is grown in large quantities. Formation of the protein by the rDNA and isolation of the protein results in the subunitvaccine.



sized both linear and cyclic peptides that stimulateimmunity similar to the complete virus for hepa-titis B and influenza (23)46,66) cf, 68). Preliminaryevidence indicates that a synthetic influenza sub-unit vaccine adequately protects animals againstseveral strains of the live virus, but more testsmust be done before synthetic subunit vaccinesare ready for clinical evaluation.

If synthetic vaccines prove effective, they maybe produced in rDNA systems by cloning the DNAcorresponding to the synthetic polypeptide andproducing the vaccine using microbial bioproc-esses. Fairly small amounts of protein may be re-quired, with a few kilograms sufficing for millionsof vaccine doses. However, it remains to be seenwhether economics favor development of micro-bial bioprocesses over chemical synthesis. On theother hand, multivalent vaccines (vaccines thatprotect against several diseases) may be createdby combining a number of peptide sequences toelicit responses to several different antigens andthus broaden the range of synthetic subunit vac-cines. Such multivalent vaccines may be more eco-nomically produced using biotechnology.

In order for both synthetic and rDNA-producedsubunit vaccines to be more effective, better im-munizing systems must be devised to promote ac-tive immunity. Live (attenuated) vaccines prolif-erate within the body, thus sustaining immuneresponses that are necessary for long-term pro-tection. On the other hand, subunit vaccines aredestroyed rapidly. Delivery systems are being for-mulated by coupling the subunit proteins withlarger carrier proteins that evoke better immuneresponses (e.g., 2), and by encapsulating subunitvaccines in lipid packages that allow the vaccineto diffuse slowly throughout the body and pro-long exposure (92).

A potential live virus vector system is beinginvestigated using vaccinia virus, a virus notpathogenic to humans (131). DNA encoding HBsAgis joined to DNA sequences (“vaccinia virus pro-moters”) which control transcription of the HBsAgDNA. This rDNA construct is inserted into vac-cinia virus, and a “living” vaccine that synthesizesand secretes the HBsAg is produced. Rabbits re-ceiving injections of this live vaccine rapidly pro-duce antibodies against HBsAg, and the vaccine

is currently being tested in chimpanzees. The in-vestigators are doing further work on the use ofthis live virus vector system for other vaccines.Such live vaccines may prove useful after a single,easily administered dose of the vaccine wheresubunit vaccines fall short in achieving a suffi-cient immune response.

Bacterial disease vaccines

Unlike viruses, whose surfaces are relativelysimple and offer protein targets to which vaccinescan be directed, bacteria and other microbialpathogens have complex, dynamic surfaces whichin many cases defy vaccine development. Mostbacterial surfaces are composed mainly of lipidsand polysaccharides, which are molecules derivedfrom complex biosynthetic pathways determinedby many genes. Hence, bacteria are not as ame-nable as viruses to genetic manipulation tech-niques used in subunit vaccine technology.

Biotechnology is being used in several ways tocreate novel vaccines against bacterial infections,but the results with bacterial vaccines at presentare not as extensive as those with viral vaccines.It is necessary first to identify targets that mightbe suitable for vaccine development. On the sur-face of some bacteria, such as Gonococci a n dseveral pathogenic E. coli strains, for example,there are certain proteins which perform func-tions essential to the disease mechanisms. Thoughsubunit vaccine technology has not been widelyexplored in bacteria, these proteins may providetargets for subunit vaccines comparable to thosebeing made against viruses.

The genes responsible for a bacterium’s viru-lence can be genetically manipulated to createviable, harmless mutants. These mutant bacteria,which outwardly resemble the pathogenic form,can be introduced into the body, where they elicitthe production of antibodies against both mutantand pathogenic bacteria. * Such mutant bacteriamight be used to colonize body spaces prone toinfection and to provide long-lasting immunity(51).

● As discussed in Chapter 6: Agriculture, such bacterial vaccinesare currently being introduced to the animal agriculture industryto treat colibacillosis, a common bacterial infection in newborn farmanimals.


A similar method involves using mutation/selec-tion procedures on pathogenic bacteria to selectbacteria that die after a short period of time inthe body. For instance, a mutant of the typhoid-causing bacterium, Sahnonella typhi”, type Ty-21a,accumulates toxic amounts of galactose duringgrowth and causes its own death. This mutantcan proliferate within the body for a short time,and its presence elicits an immune response thatprotects against the disease. The Swiss Serum andVaccine Institute, in association with the FrenchInstitut Pasteur, has developed an oral typhoidvaccine of this type.

Other workers have taken this typhoid vaccinestrain and incorporated a plasmid with a gene en-coding a protein normally produced by Shige]lasonnei, one of the bacteria which cause dysen-tery. In mice, this “hybrid” strain elicits immuneresponses that protect against both the dysenteryand typhoid organisms. Thus, it may be possibleto construct a multipurpose oral, attenuated ty -phoiddysentery vaccine organism that will pro-duce “protective” antigens for both dysentery andtyphoid (51).

Parasitic disease vaccines

Diseases caused by parasites, including pro-tozoa, pose major barriers to acceptable healthstandards for millions of people throughout theworld (see table 25). Many of these organisms ex-

hibit even more extraordinary degrees of com-plexity than bacteria, however, and lack of basicknowledge restrains new vaccine development invirtually all cases (51). As basic knowledge ac-crues, immunization against diseases caused byparasites may eventually be the greatest break-through in health care provided by biotech-nology. *

Progress in developing malaria vaccines ex-emplify efforts to realize biotechnology’s poten-tial in combating parasitic diseases. Because of thelack of a vaccine, combined with parasitic resist-ance to the drugs used in malaria control (e.g.,chloroquine), malaria remains the most prevalentinfectious disease in the world.** Historically, thesearch for malaria vaccines has been hamperedby difficulties in growing the malarial parasitePlasnmdium (which is transmitted by femaleAnopheles mosquitoes) in the laboratory. Otherdifficulties stem from Plasmodium's complex life-cycle and the apparent ability of the parasite toevade the body’s immune system. In addition, vac-cines based on killed, injected whole Plasmocfiapresently require the use of powerful adjuvants(additional components of vaccines that boost im-mune responses) in test animals which are toostrong for human use.

The complexity of Plasmodium's lifecycle hintsat the difficulties in developing a vaccine that pro-tects against all forms of malaria. As shown in fig-ure 14, the sporozoites, injected into the blood

Table 25.—Estimated Worldwide PopulationsAffected by Parasitic Diseases in 1971

Diseased populationType of Parasite (in millions)

Intestinal parasites:Ascariasis . . . . . . . . . . . . . .Ancyclostomiasis. . . . . . . .Amoebiasis . . . . . . . . . . . . .Trichuriasis . . . . . . . . . . . . .

Periocular parasites:Trachoma. . . . . . . . . . . . . . .

Systemic parasites:Filariasis . . . . . . . . . . . . . . .Schistosomiasis. . . . . . . . .Malaria. . . . . . . . . . . . . . . . .Leishmaniasis. . . . . . . . . . .Try~anosomiasis . . . . . . . .

650450350350

Greater than 400

250180100

N.A.a

7

aN,A. = Information not available.SOURCE: Office of Technology Assessment, based on data from World Health

Organization, Repori for the Special Programme for Research and Trahr-ing In Troplcai Diseases, Geneva, 1976.

● The U.S. National Academy of Sciences and the Agency for In-ternational Development convened meetings in July and December1982 on the applications of biotechnolo~ most significant for thedeveloping world. Recommendations were made with respect toresearch priorities on the basis of applicability of the new technol-ogies and other considerations (88,145). The only human parasiticdiseases that ranked among the top priorities for development atthis time were leishmaniasis and malaria. Leishmaniasis is a familyof diseases, caused by sandfly-transmitted protozoa, which is con-sidered to have grossly underestimated public health importancein South America, Africa, and the Middle East. It was identified forspecial attention because there is evidence that immunity can bedeveloped by people in sandfly-infested areas over a period of time.An understanding of this immunity may provide ways to preventleishmaniasis.

● ● There are now an estimated 300 million malaria cases per yearand a very high mortality rate for children (I million deatha in Africaalone per year) (158). About 850 million people live in areas wheremalaria continues to be transmitted despite activities to control it.An additional 345 million people reside in areas with little or noactive malaria control efforts. Over half of the health budget of In-dia is spent on malaria control. Resistance to both drugs and insec-ticides and the number of new malaria cases are all increasing atalarming rates (155). No vaccine is currently available.



—


stream during the mosquito bite, infect liver cellsto initiate infection. Large numbers of merozoites,the next life-stage, proliferate within the liver cellsand, bursting into the blood stream, successive-ly infect large numbers of red blood cells. Someof the merozoites remain blood-borne; othermerozoites develop into gametocytes, which arepicked up by mosquitoes, reproduce to form newsporozoites, and begin the cycle anew. Additional-ly, Plasmodium has the ability to evade the im-mune system over time.

Since the pathology of malaria is caused large-ly by Plasmodia in the merozoite stage, themerozoite appears to be the best target for vac-cines. Even one sporozoite reaching a liver cellis capable of causing malaria, so vaccines againstthis stage must kill every sporozoite to be effec-tive. The gametocyte itself is not pathogenic; anantigametocyte vaccine, therefore, would serveonly to reduce the transmission of the disease.

Many investigators (particularly in the UnitedStates, the United Kingdom, and Switzerland) aredeveloping MAbs that may be useful in malariaresearch (153). Antisporozoite and antimerozoiteMAbs that inhibit the in vitro multiplication ofWasmodia and antigametocyte MAbs that inac-tivate male gametes have been developed (153).Also, MAbs that destroy merozoite-infected redblood cells have been developed. Such MAbs mayprove useful as vaccines that confer passive im-munity (19,87,160).

The most promising use of such MAbs is in theisolation of surface antigens which might be usedfor the development of subunit malarial vaccines.Though quantities of surface antigens obtainedby MAb precipitation are too small for use as vac-cines, these purified antigens provide a startingpoint for developing other MAbs with an evengreater affinity for Plasmodium for use as passivevaccines. They may also provide a starting pointfor using rDNA technology to isolate largeamounts of antigen. Workers at New York Univer-sity (NYU) recently reported the successful clon-ing and expression in E. COLZ” of a surface antigenfrom the sporozoite stage of one species of Plas-

modium using rDNA technology (28), and similarefforts to obtain quantities of antigen from otherPlasmodium species and life stages using rDNA

technology are underway (54). These rDNA-pro-duced surface antigens may serve as protectivemalarial vaccines.

NYU’s “antisporozoite vaccine” has been thesubject of a widely publicized dispute betweenNYU; Gmentech (U.S.) (the proposed manufactur-er of the vaccine); and the World Health Organiza-tion (WHO) (which, with the U.S. Agency for In-ternational Development, sponsored NYU’s basicresearch with the standard provision that allWHO-funded work must be “publicly accessi-ble’’). * When it became clear that Genentechwould not obtain an exclusive license to commer-cialize the vaccine, the company bowed out of ne-gotiations. At present, no other arrangements topursue large-scale rDNA production of the spor-ozoite antigen have been made.

As mentioned earlier, a vaccine effective againstonly the sporozoite stage of a single Plasmodiumspecies may not prove to be fully protectiveagainst malaria. Ultimately, malaria vaccines mayinclude a variety of stage-specific antigens thatresult in combined sporozoite and merozoite neu-tralization, accelerated removal of infected redblood cells, and prevention of gametocyte trans-mission to the mosquito (158). The delay of fur-ther development of NYU’s potential milestonesporozoite vaccine imposed by the turmoil overcommercialization, however, has raised concernthat, in the future, profit motivations may delaythe development of urgently needed pharmaceu-tical products made possible by biotechnology(7’5,90). Despite their promise, the developmentof effective malarml“ vaccines appears to be severalyears away.

For a variety of reasons, biotechnology holdsless promise for vaccine solutions for other par-asitic diseases than for malaria. For most of theparasites, there are formidable problems relatedto culture of the pathogenic organisms and es-tablishment of meaningful models of the humandisease in animals. For example, the parasite thatcauses schistosomiasis, a disease that ranks sec-ond only to malaria as a cause of morbidity and

“A similar situation aroae with regard to the cloning of severalmore malarial surface antigena at Walter and Eliza Hall Instituteof Medical Research in Australia. This research was also partiallyfunded by WHO (110).


mortality from parasitic organisms, is difficult to Much basic research on parasites is needed inculture in the laboratory. The ability of this para- order to develop effective antiparasite vaccinessite to alter its susceptibility to host immunological using rDNA technology. The techniques of bio-responses and the difficulty in obtaining sufficient technology have accelerated the study of parasiticquantities of an antigen have hampered efforts diseases, but urgently needed pharmaceutical ap-to develop a vaccine for schistosomiasis. placations in this area are still in early stages.

Antibiotics

For the past three decades, antimicrobial agentsfor the treatment of infectious diseases causedby bacteria have consistently led worldwide salesof prescription pharmaceuticals. Novel antibiotics,produced mainly by traditional microbial bioproc-esses, continue to be developed and introducedeach year (especially in Japan in recent years).Methods of biotechnology such as the followingoffer strong innovative possibilities for produc-ing new antibiotics:

● “Sexual’ ’recombination. A technique knownas protoplasm fusion, whereby the contentsof two micro-organisms are fused to give onecell, enables researchers to induce rapid im-provements in bacterial germplasms. Proto-plasm fusion allows the rejuvenation of strainsof industrial microbes that have lost vigor asa result of mutation and selection proceduresthat have been performed to increase theirantibiotic productivity. The fusion of micro-organisms is beginning to yield new (hybrid)antibiotics (22). *

● Through protoplasm fusion and selection, researchers at Bristol-Myers (U. S.) developed an improved method of producing purerpenicillins that has accounted for 8 percent per year improvementin penicillin productivity over the past 4 years. Other genetic ap-proaches produced 60 to 70 percent improvements in yields ofcephalosporina (a class of antibiotics) in the same period. Geneticresearch by Pfizer, Inc., at laboratories in the United Kingdom andUnited States, have gradually lowered costs of producing oxytetra-cycline, a long eatabliahed antibiotic, to coats similar to bulk chemicalproduction, to give prices of several dollars per kilogram (73).

● Recombinant DNA technology. Gene codingfor enzymes and other metabolic proteinscan be cloned into antibiotic-producingmicroorganisms to add steps to existingbiosynthetic pathways that improve productsor manufacturing processes. Ongoing re-search includes: 1) the rDNA-mediated trans-fer of acyltransferase genes among speciesof bacteria to obtain solvent+xtractablecephalosporins (149); 2) the combination ofgenes via rDNA technology and transforma-tion to obtain direct, efficient synthesis of theantibiotic amikacin (149); and 3) Eli Lilly’sutilization of rDNA technology to improve theproduction of the antibiotic tylosin (4).

The combination of new and traditional tech-nology in the pharmaceutical industry holds tre-mendous potential for improvement of micro-organisms used in antibiotic production and theisolation of new antibiotic products. Japanesepharmaceutical companies, with their extensivebioprocessing resources, are placing great empha-sis on new antibiotic research (114). This emphasismay be due to the fact that antibiotics comprise25 percent of (1981) ethical drug sales in Japan(compared to about 8 percent in the united States)and that at least 28 percent of the antibiotic salesin Japan now arise from antibiotics produced inthe United States (120,125).

Monoclinal antibodies

MAb technology currently leads other forms of largely due to MAb in vitro diagnostic products.biotechnology in commercial use, as measured by In vitro diagnostic products do not have to under-numbers of products on the market. Its lead is go the same rigorous safety testing required of


pharmaceuticals used within the body (in vivo). *The increasing number of MAb-based productsalso stems from advances in knowledge about hy -bridoma technology and antibody functions. Fur-ther refinements of MAb technology will allowMAbs to be used in numerous applications in thepharmaceutical industry, including in vivo diag-nosis, prophylaxis, and therapy.

Hybridomas (MAb-secreting cell lines) derivedfrom human (rather than rodent) cells have onlyrecently become available for use in the pharma-ceutical industry. The use of human-cell-derivedMAbs in in vivo pharmaceutical applicationsshould give fewer adverse immune reactions thanthe use of mouse-derived MAbs. Though the prep-aration of human hybridomas is in its technicalinfancy, as described in Chapter 3: The Technol-ogies, advances in producing MAbs from humancell lines will encourage MAb-based applicationsfor new and replacement medicines.

Diagnostic products

IN VITRO DIAGNOSTIC PRODUCTS

The roster of MAb-based in vitro diagnosticproducts is growing rapidly. Table 26 providesa list of the products approved for use in theUnited States as of June 1983.** MAb technologyis being used to make both novel diagnostic prod-ucts and products to replace conventional, poly -clonal diagnostic products. Although the compet-itive advantages of MAb products must ultimate-ly be demonstrated in the marketplace, such prod-ucts may prove superior to traditional methodsused to identify infectious diseases, hormonalchanges, or the presence of cancer.

Recently developed applications of MAbs for invitro diagnosis include the following:

● Diagnosis of human venereal diseases. Con-ventional diagnosis of several common vene-real diseases—gonorrhea, chlamydia, andherpes simplex virus —is hampered by time-consuming cell culture requirements. Aspeedy, sensitive MAb-based diagnostic kit for

● The regulation of pharmaceutical products in the United Statesand other countries is discussed in Chapter IS: Health, Safety, andEnvironmental Regulation.

● “A longer list of approved MAb products for research and diag-nostic use appears in Monodonal Antibodies in Cliru”cal Mml”cine (77).

●

●

chlamydia has been produced by Genetic Sys-tems Corp. (U.S.), in collaboration with SyvaCo. (U. S.) and the University of Washington(93), and MAb-based diagnostic kits for allthree types of infections maybe used in theclinic in the near future (38,93 ).*Diagnosis of hepatitis B and other viral infec-tions. MAb-based diagnosis of hepatitis B in-fection is reportedly 100 times more sensitivethan conventional diagnosis based on poly -clonal antibodies (6,151). The MAb diagnosticproduct, developed by Centocor (U. S.) withMassachusetts General Hospital, may benefitthe blood banking industry, where unambig-uous screening for hepatitis is crucial. MAbsare also proving satisfactory for diagnosingrotavirus and cytomegalovirus infections andfor distinguishing between strains of influen-za viruses that have until now been indistin-guishable by conventional methods (80).Diagnosis of bacterial infections. The recu-peration of hospitalized patients is often jeop-ardized by infections with bacteria such asPseudomonas aerouginosa, and diagnosismay take several days before treatment is be-gun. Also, group B streptococcal infectionsare the most common serious infections ofnewborn infants in the United States. Priorto availability of MAbs, there was little ap-plication of immunoassay to the diagnosisof bacterial infections. Genetic Systems, in ajoint venture with Cutter Laboratories (U. S.)and its parent company Bayer (F. R.G.), is de-veloping diagnostic and therapeutic MAbproducts for Pseudomonas infections (124).Researchers at the University of Pennsylvaniareport that diagnosis times for streptococcal

*New infections of gonorrhea, chlamydia, and herpes simplexvirus type 2 (HSV2) are estimated to exceed 15 million per year inthe United States. Approximately 1 million new cases of gonorrheaare reported annually to the U.S. Centers for Disease Control. Itis estimated that the true prevalence of gonorrhea in the UnitedStates is 3 million cases annually. Chlamydia infections are not re-ported and their prevalence can only be estimated. Clinically, theinfection rate is estimated to be three to four times that of gonor-rhea (approximately 10 million cases annually in the United States).Separately or in combination, chlamydia and gonorrhea are respon-sible for an estimated 200,000 to 300,000 cases of pelvic inflamma-tory disease per year resulting in infertility in 50,000 to 100,000women. HSV2 infections are becoming increasingly common, withapproximately 200,000 to 300,000 new cases occurring each year.These new cases accrue on an estimated base of 10 million individ-uals who are already infected (38).

Ch. 5—Pharrnaceuticals ● 145

Table 26.—In Vitro Monocionai Antibody Diagnostic Products Approved in the United States’

Manufacturer Analyte Date approved

Hybritech, Inc. . . . . . . . . . . . . . . . .lgEHybritech, Inc. . . . . . . . . . . . . . . . .PAPHybritech, Inc. . . . . . . . . . . . . . . . .HCGHybritech, Inc. . . . . . . . . . . . . . . . .T CellHybritech, Inc. . . . . . . . . . . . . . . . .FerritinAbbott . . . . . . . . . . . . . . . . . . . . . . .PAPAbbott . . . . . . . . . . . . . . . . . . . . . . .CEAAbbott . . . . . . . . . . . . . . . . . ... ...CEAOrtholil . . . . . . . . .. .. .. ... ... ..OKT-11Centocor . . . . . . . . . . . . . . . .. .. ..Anti-RabiesHybritech, Inc. .. .. .. ... ... ....HCGHybritech, Inc. .. .. .. ... ... ....HGHMallinckrodt, inc. .. .. .. ... ... ..Total TiHybritech, Inc. . . . . . . . . . . . . . . . .ProlactinClinical Assays.. .. .. .. .. ... ...’’sl-lgEBiogenex Laboratories ... ... ...@-HCGHybritech, Inc. .. .. .. ... ... ....HCG (EIA)New Horizons . . . . . . . . . . . . . . . . .GonogenMonoclinal Antibodies, Inc. ....UCGHybritech, inc. .. .. .. ... ... ....TSHAfiergenefics (Div.of Axonics). ..lgFast@t@ (Specific lgE)Becton Dickinson&Co. ... .....T4Syva Co.. . . . . . . . .. .. .. .. .. ... .ChlamydiaMiles Laboratories . . . .., .. .. ...GentamicinAllergenetics (Div.of Axonics). ..TotallgFASTSTCarter-Wallace, inc. .. ... ... ... .@HCGHybritech, Inc. . . . . . . . . . . . . . . . .Tandem-E@ FerritinOrtho . . . . . . . . . . . . . . . . . ... ... .RubefiaPCL-RIA . . . . . . . . . . .. ... ... ....HCGQuidel Home. . . . . . . . . . . . . . . . . . HCG b

Ventrex Labs, Inc. .. .. .. ... ... .Enzyme TSHQuidel Home. . . . . . . . . . . . . . . . . . HCG b

Diagnon . . . . . . . .. .. .. .. .. ... ..FerritinBTC Diagnostics .. .. ... ... ....HCGImmunlok. . . . . . . . . . . . . . . . . . . . .ChlamydiaMonoclinal Antibodies ... ... ...HCGVentrex LabsV inc. .. ... ,.. ... ..lgE (total)Organon Inc. . . . . . . . . . . . . ... ...HCGBioGenex Laboratories . . . . . . . . .RIAGen~-HCGRIA KitMicromedia System, Inc. .. .. ...Micromedia @-HCG RIAOrganon Inc. . . . . . . . . . . . . . . . . . .Neo-Presmosticon Duoclon Tube Kit

5/29/819/1/81

10I13I817126J8110I19I811}191823131823/29/82416/82

41161824/23/826181826/9/82

6I1OI826118/827/13/8271221828/4/829/24/8210/8/82

11/10/821217182

12I1OI8212/14/821113/831/20/832/241833/15/834/5/834/14/834126/834/261834/28/834/28/8341291835125/8351251835/26/835/26/836/1/836/3/83

aAsof61141S3.%heeekitesreforhorneuae.

SOURCE: U.S. Department of Health and Human Services, Food and Drug Administration, National Center for Devices andRadiological Health, 1983.

infections maybe reduced to 2hours using ● Pregnancy testing. Products composed ofMAb-based products, Additionally, Becton polyclonalantibodies have long beenusedtoDickinson (U.S.) has introduced a MAb kit detect high levels of human chorionic gonad-that detects the bacteria responsible for men- otropin (hCG) in the blood as an indicator ofingitis infection. The bacterial strains can be pregnancy. Large amounts of antisera are re-detected in 10 minutes, and the company’s quired to circumvent the need for radioac-price for each test is $2 (17). tive isotope labels, which often accompany


immunoassay. MAb technology is an eco-nomic means of producing the high quantitiesof antibody required in pregnancy testing. *Cancer detection. The detection and quanti-tation of indicators related to malignant tu-mors is potentially one of the most importantapplications of immunoassay and MAbs. Agreat deal of work on tumor markers isunderway, and a few MAb-based productshave been approved for marketing. In some

cases (e.g., prostatic acid prosphatase andCEA), MAbs are used used to detect blood-borne antigens shed by the tumor; in others,the MAb reagents are used to identify tumorcells by staining tissue specimens.

IN VIVO DIAGNOSTIC PRODUCTS

Diagnosis of some diseases requires identifica-tion and localization of the disease within thebody. Antibodies with detectable markers (e.g.,radioactive chemicals) provide highly specificmeans for accomplishing these ends. Antibodiesinjected into the body, although used in diagnosticapplications, are considered drugs; thus, theyrequire extensive testing prior to approval formarketing.

MAb technology provides quantities of antibod-ies for testing, and MAbs are being evaluated inan increasing number of in vivo diagnostic appli-


cations. one application involves radioisotope-labeled MAbs that bind to cardiac myosin (a ma-jor heart muscle protein) to locate and character-ize myocardial infarcts (the most common typeof “heart attack”) (55,56). Another application in-volves the use of radioisotope-labeled MAbs thatbind to antigens on cancer cells, but results to datehave not been encouraging, As yet, no antigenthat occurs on cancer cells exclusively has beenfound. A few clinical trials of in vivo diagnosisusing MAbs have been undertaken, but expertsagree that clinically useful products will require5 or more years of further development (48). Suc-cess in this work could provide useful informa-tion prior to and following surgery.

In certain types of malignancies, such as plas-macytomas whose surface immunoglobulins arehomogeneous and particular to the tumor, MAbscan be made against these proteins and then usedas diagnostic or therapeutic agents. The therapeu-tic approach has been used in clinical trials forsome types of cancer with encouraging results(20,109).

Preventive and therapeutic products

Applications of MAbs to prevent or treat dis-eases are being pursued on two fronts: 1) ad-ministration of MAbs as passive vaccines to pro-tect against specific diseases, and 2) couplingcytotoxic agents (e.g., diptheria toxin, ricin, orcobra venom) to MAbs that direct the agents todiseased cells (7).

Much of the technology being developed thatuses MAbs as diagnostic reagents may lead to de-velopment of MAb-based (passive) vaccines. Thisis especially true in the case of the viral diseaseshepatitis B, herpes, and cytomegalovirus. Untilrecently, no cell culture system for hepatitis B hasbeen available; however, a human liver tumor hasbeen adapted to cell culture, and these tumor cellssecrete the HBsAg (23). The availability of thisHBsAg may make MAb preparation possible, lead-

ing to MAbs that neutralize the virus and areeffective as a passive vaccine. Infants born towomen with hepatitis B apparently benefit fromtreatment with human serum that contains anti-bodies against hepatitis B (78), and such serumis used prophylactically in many parts of theworld. MAb technology provides a means forproducing large quantities of antibodies againsthepatitis B.

Scientists at Genetic Systems have produced hu-man MAbs against Pseudomonas, Klebsiella, andE. coli, all gram negative bacteria which accountfor serious problems in patients with depressedimmune system function (83). Clinical trials ofthese MAbs as passive vaccines are underway.

Trials of MAbdirected cytotoxic agents againsttumor cells indicate that while cytotoxic agentssuch as cobra venom factor can be made to directtheir activity in a very specific fashion againsttheir targets, problems with finding cancer-spe-cific antigens noted earlier restrain such applica-tions of MAbs (36,60,147,148,161). other prob-lems associated with the use of MAbs in eitherchemotoxic or direct anticancer therapy includethe

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following:

toxicity problems associated with rapid ad-ministration of antibodies,cancer defense mechanisms that apparentlyinvolve shielding of target antigens by tumorcells (109),the difficulty of getting the cytotoxic agentsinside the tumor cells, andthe difficulty of getting the agent to the ma-jority of cells of a solid tumor.

MAbs will undoubtedly play a major role in thepharmaceutical industry in the future, both asproducts and reagents for pharmaceutical re-search. R&D in the use of MAbsas pharmaceuti-cals is proceeding rapidly in the United States,where several MAb-based biotechnology compa-nies have emerged, in the United Kingdom, whereMAb technology was invented, and in Japan.


DNA hybridization probes

DNA ‘(hybridization” occurs when two singlestrands of DNA join to reform the double helix(see Chapter 3: The Technologies). The DNAstrands must have exact, corresponding se-quences of nucleotide bases for hybridization tooccur; thus, a given strand can hybridize onlywith its complementary strand.

DNA hybridization is a powerful tool in molec-ular biology. Radioactive phosphorus is commonlyincorporated into one of the DNA strands, the“probe,” so that the hybridization process can befollowed using the radioactive label. DNA hybridi-zation is used to identify and isolate for furtherstudy particular DNA sequences (and cells thatbear this DNA). DNA hybridization is also usedto determine where certain DNA sequences arelocated on chromosomes. In addition, DNA probesare being tested as reagents in clinical medicine.Probe DNA obtained from a pathogenic organismsuch as a virus, for example, can be used to iden-tify the presence of that virus within human cells,thus allowing specific diagnosis based on whetheror not the radioactive DNA probe hybridizes withDNA in the cells.

Radioactive labeling of DNA hybridizationprobes raises problems of safety, handling, anddisposal that in many cases limit the use of suchprobes to the research laboratory. Furthermore,since radioactive phosphorus loses its radioactivestrength rapidly, only small batches of probesmay be practically labeled with radioactivity atany given time.

Several methods to label DNA probes with non-radioactive substances are emerging. The mostpredominant new method, developed and pat-ented by Dr. David C. Ward and his colleaguesat Yale University’s School of Medicine, is to cou-ple chemically the molecule biotin to DNA. Biotin-labeled DNA probes hybridize with the targetDNA and the hybrids are identified using com-pounds that recognize biotin (62) (see fig. 15).With such detection systems, only a few hoursare required to identify DNA sequences usingbiotin-labeled probes, whereas 1 or more days arerequired when radioactive phosphorus labels areused. Additionally, biotin-labeled probes have the

potential to be more sensitive than radioactiveprobes (70).

Nonradioactively labeled DNA is stable and safeto handle, so these probes can be prepared inlarge (manufacturer’s level) quantities and storedfor long periods of time. Almost any given shortDNA fragment can now be chemically synthesizedfor use as a probe rather than isolating the frag-ment from a natural source. Another method ofpreparing DNA for use as probes is the isolationof DNA fragments made by restriction enzymes.Several companies (e.g., Applied Biosystems (U.S.),University Genetics (U.S.)) are working towardproducing a large repertoire of DNA fragmentsfor use as probes.

The ready availability of DNA probes and theconvenience of nonradioactive labeling is likelyto encourage widespread use of DNA hybridiza-tion probes in the near future. While many usesfor DNA probes exist in basic research, developerssuch as Enzo Biochemical (U. S.) and Cetus Corp.(U. S.) are striving to produce probes for clinicaluse, where much larger markets exist. Somepromising clinical applications of DNA probes in-clude the following:

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Diagnosis of infectious diseases. DNA probesthat identify and differentiate among speciesof bacteria that cause diarrheal diseases havebeen made. other DNA probes may proveuseful in diagnosing human sexually trans-mitted diseases. DNA probes to detect infec-tions of rotavirus, cytomegalovirus, hepatitis,herpes, and other viruses are being devel-oped (29), In some clinical situations, DNAprobes may be more useful than MAbs fordiagnosis.Prenatal diagnosis of congenital abnormalitiessuch as sickle cell anemia (97), beta-thalasse-mia (101), and duchenne muscular dystro-phy.Diagnosis of disease susceptibility. Research-ers in several laboratories are developingDNA probes that recognize DNA abnormali-ties leading to such conditions as atheroscle-rosis, the leading cause of death in the UnitedStates (5).


Figure 15.—DNA Probe Filter Assay

Sample Deposit organismson a matrix

Break open organismsand isolate the DNA

Treat the DNA with chemicalsto separate the strands and

bind them to the matrix

2 < - - ‘ -

Add labeled DNA probes DNA probes hybridize Wash away extra probesto complementary and add signal moleculesDNA in the sample to identify

SOURCE: A. Klausner and T. Wilson, “Gene Detection Technology Opena Doors for Many Industries,” Wotechnology, Auguat 1983; Ron Carboni, N. Y., N. Y., artist.

The success of DNA probes for clinical use prob-ably depends most on convenience and safe label-ing of the DNA. Enzo Biochem (U.S.), capitalizingon Ward’s biotin labeling technique, markets kitsfor labeling any given DNA sequence with biotinfor use as a probe. Enzo has granted Ortho Diag-nostics, a subsidiary of Johnson &Johnson (U.S.),exclusive worldwide marketing rights for itshuman diagnostic products. Cetus (US,), the ex-clusive licensee of a patent that involves diagnos-tic applications of DNA probes stemming fromwork at the University of Washington, is also em-phasizing diagnostic applications of probes (91).Other NBFs that have amounced their intentionsto develop commercial diagnostic products basedon DNA probe technology are Amgen (with back-ing by Abbott Laboratories) and Integrated Genet-

ics (in collaboration with the University of Califor-nia, San Diego).

The development of DNA hybridization probesrepresents a challenge to MAb technology forclinical diagnostic applications. MAb kits fordiagnosing human venereal diseases are now onthe market, but proponents of DNA hybridizationprobes claim that DNA hybridization offers aneven more specific method of diagnosing infec-tions (58). DNA hybridization can be performedwith a minimum of tissue handling and may beused on some fixed tissues that are not amenableto MAb use. Ultimately, the relative strengths ofDNA hybridization probes and other diagnosticproducts must be assessed on an individual basis.

150 . commercial Biotechnology: An International Analysis

Commercial aspects of biotechnologyin the pharmaceutical industry

The path leading from the concept for a drugto a marketable product is arduous, costly, andextremely speculative. Discovery and develop-ment costs alone in the United States are esti-mated to range from $54 million to over $70 mil-lion per drug (43). Despite the generally low re-turns on the majority of potential drugs, however,high investments in pharmaceutical R&D con-tinue. With an average of 11.5 percent of annualsales invested in R&D (99), the U.S. pharmaceu-tical industry ranks only below the informationprocessing and semiconductor industries in termsof R&D as a percentage of annual sales (16).

During the past 40 years, the pharmaceuticalindustry has given increasing attention to R&D,and extensive government regulation of pharma-ceutical products has evolved. Despite the increas-ing R&D commitments, however, recent trendsindicate that the rate of innovative return to phar-maceutical companies throughout the world hasdeclined (89). In short, fewer new drug introduc-tions are emanating from larger research com-mitments by the public and industry (40).

Reasons most often cited for this decline in theUnited States center on the burdens imposed byGovernment legislation, including high costs ofobtaining FDA approval, brevity and insufficien-cy of patent protection for new drugs, sponsor-ship of competition and product undercutting byState substitution laws and maximum allowablecost programs, and other regulatory factors thatact as disincentives for renewed industrial R&Dfor new drugs. other popular hypotheses forlower pharmaceutical innovation are decentraliza-tion of R&D resources by pharmaceutical compa-nies to other industries such as specialty chemi-cals, cosmetics, and agricultural products, and in-creased displacement of R&D in industrial coun-tries by R&Din less developed countries, empha-sizing substitution rather than innovation.

Although biotechnology should not be viewedas a panacea for the problem of diminishing in-novation in the pharmaceutical industry, it doesoffer promise in augmenting existing technologies

in the pharmaceutical industry. In addition to al-lowing improvements in pharmaceuticals them-selves, the adoption of biotechnology may pro-vide ways for companies to streamline R&D costsfor such things as biological screening, pharma-cological testing, and clinical evaluation of newproducts. To a large degree, pharmaceutical de-velopment involves the correlation of functionand molecular structure, and biotechnology mayaid in making such correlations. Prior knowledgeabout the structure of drug receptor molecules,as gained partially from gene cloning and DNAsequencing research, for example, could supplyinvestigators with information about which struc-tures of new drugs might be effective in reactingwith these receptors. This predictive ability maybe increased by the use of computers to selectappropriate drugs for development, as has beendone in the development of synthetic subunit vac-cines (67,68).

The costs of applying biotechnology to the de-velopment of new pharmaceutical entities cannotbe readily determined at this time. In most in-stances, however, biotechnological methods ofproduction are probably not yet cost-competitivewith conventional methods. With biotechnology,as with other new technologies, there are costsassociated with learning the technology that willdiminish as facilities and skills are acquired.Achieving the limited goal of supplying MAbs suc-cessfully to manufacturers of in vitro diagnosticproducts, it has been estimated, will require acumulative 3-year investment of $3.5 million to$4 million, and final immunodiagnostic productdevelopment may require 5 to 10 times thisamount (138). The costs of commercial rDNAwork are considerably higher. Although expend-itures are rarely disclosed, indications of the costof production for rDNA produced products canbe gleaned from Schering-Plough’s (U.S.) $6 mil-lion investment in a pilot-scale bioprocessing andpurification facility (52), Genentech’s drive to raise$32 million to sponsor clinical testing and develop-ment of its rDNA produced tPA (32), and Eli Lilly’s$60 million investment in facilities to produce hI(129).


The international pharmaceutical market rep-resents a major source of trade between nations,and foreign sales are comprising increasing per-centages of total sales in the developed countries.From 1975 to 1981, for example, U.S. companies’control of their domestic market fell to 73 per-cent from 85 percent, and Japanese companies’share of their domestic market fell to 69 percentfrom 87 percent (120). Foreign sales account for43 percent of total sales by U.S. ethical drugmanufacturers. West German and Swiss compa-nies are even more oriented toward foreign mar-kets than their U.S. counterparts (40).

Many companies conducting biotechnologyR&D are considering markets on a global scale,and for that reason, international market dif-ferences are likely to have strong effects on thepattern of biotechnology’s introduction to thepharmaceutical industry. These differences aresuggested by the fact that the most widely usedpharmaceuticals in the U.S. market are neuroac-tive drugs, while those most widely used in for-eign markets are anti-infective compounds. Thus,national preferences lead to differences in thechoice of R&D ventures among leading compa-nies, as exemplified by Japanese companies’ in-terest in thrombolytic compounds. The potentialof these new agents is more readily appreciatedby Japanese drug firms than their U.S. counter-parts, and thrombolytic agent R&D efforts by U.S.NBFs are underwritten largeIy by Japanese com-panies.

International differences of pharmaceutical usemay also make the high costs associated with

developing new methods such as biotechnologymore acceptable in certain nations. In Japan,where blood products are imported because ofcultural barriers to domestic collection, theGovernment may choose to subsidize the costsfor domestic production of HSA by rDNA tech-nology (which is likely to exceed the current priceof HSA on the world market) rather than perpet-uate the import trade. Such an action mightenable firms involved with HSA biotechnology inJapan to move more rapidly along the manufac-turing learning curve with generally applicabletechnology. Ultimately, this could reverse Japan’ssubstantial pharmaceutical trade debt with theUnited States.

Biotechnology is likely to augment the interna-tional stature of the pharmaceutical industrythrough international corporate arrangementsthat combine research, production, and licensingin ways that best satisfy market needs in variouscountries. Because biotechnology offers possibil-ities of creating novel pharmaceutical compoundsin large quantities and at reduced costs (e.g., Ifns,growth hormones, vaccines, and other biologicalresponse modifiers) and because many small newcompanies are involved in pharmaceutical R&D,the demands of “less glamorous” markets forproducts such as parasitic vaccines may havegreater chances of being met than they have inprevious years. Thus, biotechnology provides thepharmaceutical industry with a variety of newsources of R&D possibilities.

priorities for future research

Funding from NIH has been and will continue research that would benefit pharmaceutical inno-to be instrumental in developing biotechnology vation in biotechnology including the following:for pharmaceutical use. The new biological tech- ● clarification of the functions and mechanismsniques have dramatically increased the under- of action of immune regulators such as Ifnstanding of many disease mechanisms. Areas of and interleukin-2,


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investigation into the clinical use of neuroac- ●

tive peptides and thrombolytic and fibrino-lytic peptides,development of improved drug delivery sys-tems, ●

clarification of the mechanisms of acquiredimmunity leading to better vaccine develop-ment procedures,

Chapter 5 references

development of the ability to culture and anincreased understanding of the lifecycle ofthe world’s more debilitating protozoanparasites, andacquisition of a better understanding of thephysiology and genetics of cancer.


36

41,

42,

43,

44.

45ti

46.

47.

48.

49.

50.

25-561 0 - 84 - 11



93,

94,

95,

96,

97,

99,

100,

101!

102.

103.

104.

105.

106.

107.

108.

109.

110.

111.

112.

113.

114,

115,

116.

117,

118,

119,

120,

121,

122,duction,” June 23, 1982, p. 8.

123. Scrip 704,June 23, 1982, p. 16.

124. Scrip 713, “Cutter/Genetic Systems Joint Ven-ture,” July 26, 1982, p. 7.

125. Scrip 715, ‘(Leading Japanese Antibiotics Sur-veyed,” Aug. 2, 1982, p. 13.



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