Definition Of Generic Medicines Biology Essay

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2.1.1 Introduction

Rising in price of medicines is a phenomenon that affects all countries across the world (Ping, et al,2008;Hassali and shafie,2008; Birkett et al, 2001;Dickson,1992;Donelan et al.,1999;Ess,2003;Kanavos,1999). (1-5az).Using generic medicine is One of the most effective ways to face this fact (King and Kanavos,2002;Mould,1992;Nilsson and Melander,2000;Smeaton,2000;Tatchell,2003; Laing et al.,2001)(6-11az).

Generic medicines are less expensive than innovator medicines, generally costing between 30-75% less than innovator brand.(Carroll,1995;Lofgrn,2004;Yarnall,1994;Lieberman,1986;Karim et al.,1996) (12-16az) .Two reasons for this low coast, first generic medicines does not need to spend money on research, development and marketing(17-20), A second reason is competition; when several manufacturers produce generic versions of a medicine, competition among these manufacturers can drive down the price (13,21-23az). Savings would be achieved through the use of generic medicines helps the Ministry of Health in reviving the health situation of Iraq.

2.1.2 Definition of generic medicines

The term 'generic medicine' is used in different ways. It can mean a product marketed under the drug's approved international non-proprietary name (INN), or it can, mean a product marketed under a different brand (proprietary) name. The world health organization (WHO) defines generic medicine as "a pharmaceutical product, usually intended to be interchangeable with the innovator product, marketed after the expiry of patent or other exclusively right". In some countries, they may be marketed in dosage form and/or strengths different from that of innovator products. (WHO,1997) (20)

According to the European Generic Medicines Association (EMEA) a generic medicine is defined as: "a medicinal product which has the same qualitative and quantitative composition in active substances and the same pharmaceutical form as the reference medicinal product, and whose bio-equivalence with the reference medicinal product has been demonstrated by appropriate bio-availability studies."( Jan Donovan ,2003).A generic medicine is marketed in accordance with patent law and is identified either by its own brand name or by its internationally approved proprietary scientific name. A generic medicine is of the same quality, efficacy and safety as the original brand name product and undergoes strict scrutiny before it is licensed and given market approval (European Generic Medicines Association 2007 ) .

In the United States, the Food and Drug Administration (FDA), which is responsible for registering and marketing authorization, defines generic medicine as 'a medicine that is identical, or bioequivalent, to a brand name medicine in dosage form, safety, strength, route of administration, quality, performance characteristics, and intended use.' (FDA, 2010). The therapeutic good administration (TGA),which is the regulatory body for registering and licensing medical products in Australia defines generic medicine as "medicine which has the same qualitative and quantitative composition in term of active principles, same pharmaceutical form and bioavailability have been carried."(TGA, 1994)(24). In terms of basic generalization a generic medicine should be marketed without a commercial brand name, under the International Non-proprietary Name (INN), but practically generics can be classified categorically as branded generics, which means copies of pharmaceutical specialties with their own brand, semi-branded generics which means products marketed only under the INN followed by the name of the manufacturer , and unbranded generics medicines marketed under the INN (Garattini and Tediosi ,2000)(25).

2.1.3 Naming process of medication

Each a pharmaceutical substance is given an international nonproprietary name (INN) or a generic name (Guidance in INN,2009 ), the generic name is commonly used by physicians and pharmacist and usually created when a new drug is ready to be marketed (Gundersen, 1998).This INN is generated by the World Health Organisation (WHO) for all pharmaceuticals worldwide, using a procedure adopted by the WHO executive board(Guidance in INN,2009 ). Each INN is a unique name that is globally recognised and is public property (Guidelines on the use of international non-proprietary names,2009). An important feature of the INN system is that the names of pharmacologically related substances demonstrate their relationship by using a common "stem". as show in table ( 2.1 ). This enables healthcare professionals dealing with pharmaceutical products to recognize that the substance belongs to a specific group of substances, having similar pharmacological activity. (Guidance in INN,2009 )

Table 2.1 Generic name for common WHO approved stems


Class of drug

Generic name


Î’-adrenoreceptor antagonists

Metoprolol, atenolol


Benzodiazepine family



Antiviral agents

a cyclovir










While a brand name medication can only be produced and sold by the company that holds the patent for the drug. Usually on the basis that it can be recognised, pronounced and remembered by health professionals and members of the public (Branded and generic medicines,2009).

In addition to, a chemical name medication which is scientific name based on the compound's chemical structure and this name not uses to identify the drug in clinical situation(Kenagy,2001) .

2.1.4 Patent protection for pharmaceutical

"The term patent usually refers to a right granted to anyone who invents or discovers any new and useful process, machine, article of manufacture, or composition of matter, or any new and useful improvement thereof." (Melzer,1998; patent,2009)

Under the World Trade Organization's (WTO) Agreement on Trade-Related Aspects of Intellectual Property Rights, patents should be available in WTO member states for any inventions, in all fields of technology including pharmaceutical companies, and the term of protection available should be the minimum twenty years. Different types of patents may have varying durations (Melzer 1998 ) .Regarding to the medicines, when the period of exclusivity expires and the patent runs out, it is possible for other pharmaceutical manufacturers to market generic forms of the innovative medicine. A generic medicine has the same qualitative and quantitative composition in active substance(s) as an innovative medicine that has already been authorized ( Lamarque et al, 2008) This means that these drugs are usually interchangeable.

Although generic prescribing is encouraged, there are some circumstances in which it is preferable to prescribe by brand name. Table ( 2.2 ) outlines the main instances where generic substitution may not be suitable. (National medicine information center, 2009)

Table ( 2.2 ). Circumstances in which generic substitution may not be suitable



Differing bioavailability between formulations

(drugs with narrow therapeutic index)

Carbamazepine, lithium

phenytoin, ciclosporin, theophylline

Modified-release preparations

Nifedipine; diltiazem; morphine

Medicines of biological origin

Growth hormone; erythropoietin

Similar medicines with different administration devices

Inhalers; adrenaline pre-filled syringes

2.1.5 Generic medicines in international markets

Generic medicines markets have not developed to the same degree in European countries. This variation due to differences in generic medicines policy.(1) To highlight the need for developing generic medicines markets, a study was conducted by prof.Dr.Steven Simoens to quantifying the potential savings from increased substitution of generic for innovator medicines in a number of countries for which data were available. Focusing on the off-patent market, the top 10 active substances were selected by expenditure of innovator medicines in 2004. As these active substances have the highest expenditure of innovator medicines, they would be expected to generate the largest potential savings from generic substitution. This study shows the savings that can be made if innovator medicines for the top 10 active substances are replaced by generic medicines. Tables (3-5) show the top 10 active substances for a countries (Austria, France, and UK (Simoens,2006a).

Table 2.3 Potential savings from increased generic substitution in Austria, 2004

Active substance

Public expenditure on originator medicines(£)

Savings from generic substitutions(£)











































57,962,838 (27%)

Table 2.4 Potential savings from increased generic substitution in France, 2004

Active substance

Public expenditure on originator medicines(£)

Savings from generic substitutions(£)











































525,290,734 (35%)

Table 2.5. Potential savings from increased generic substitution in United Kingdom, 2004


Active substance

Public expenditure on originator medicines(£)

Savings from generic substitutions(£)











































349,844,935 (33%)

These tables indicate that increased substitution of generic for originator medicines can yield substantial savings for the top 10 active substances by expenditure of originator medicines.

The EU's generic market today is worth around 7 billion euros, compared to around 70 billion euros for the total European pharmaceutical market value. It is estimated that the value of the world generic market will reach about 38 billion euros in 2003.

The size of the generic market differs widely in the various EU member states. Generics make up a relatively large part of the medicine market in Germany (41%), Sweden (39%), Denmark (22-40%), the UK (22%) and the Netherlands (12%). In Italy, Spain and Portugal, generics barely count for 1% of the medicine market, compared to 3-4% in France. By contrast, generic medicines in the United States account for 40% of all prescribed medicines (Generic medicine, 2009).

2.1.6 Bioequivalence requirements for generic medicines according to FDA

Generic drug formulations are often substituted for 'brand name' (i.e., innovator) formulations by pharmacists in an effort to reduce the cost of prescription-drug therapy. In most states, generic substitution is allowed and encouraged, provided that the generic formulation is deemed to be therapeutically equivalent to the innovator formulation by the FDA.

Generally, before a new generic formulation of an innovative medicine can be marketed, the pharmaceutical manufacturer must prove that its action will be essentially the same as the innovator formulation. The purpose of the testing of generic medicine is not to demonstrate the clinical usefulness of the drug but to ensure that the generic medicine has the same relative bioavailability and bioequivalent to the innovator product.(92)

The term bioavailability defined as " the degree to which, or the rate at which, a medication or other substance is absorbed or becomes available at the targeted place in the body."(92). Bioavailability can be affected by inactive ingredients in the medicine such as additives that prevent the medication from dissolving in the stomach. For example, if a medication that is intended to be taken on an empty stomach is taken instead with food, this can also change the absorption rate and affect the bioavailability of the active ingredient(s). (bioavailability-diffenetion and example,2006 ).

Bioequivalence is defined as "the rate and extent of absorption of the test drug do not

show a significant difference from the rate and extent of absorption of the reference drug when administered at the same molar dose of the therapeutic ingredient under similar experimental conditions in either a single dose or multiple doses;" or "the extent of absorption of the test drug does not show a significant difference from the extent of absorption of the reference drug when administered at the same molar dose of the therapeutic ingredient under similar experimental conditions in either a single dose or multiple doses and the difference from the reference drug in the rate of absorption of the drug is intentional, is reflected in its proposed labeling, is not essential to the attainment of effective body drug concentrations on chronic use, and is considered medically insignificant for the drug."(Joseph,1999).While the term pharmaceutical equivalents refers to the drug products that contain identical amount of identical active drug ingredient, i.e., the same salt or ester of the same therapeutic moiety, in identical dosage forms, but not necessarily containing the same inactive ingredients.(27,91,93). Drug products are considered to be therapeutic equivalents only "if they are pharmaceutical equivalents and they can be expected to have the same clinical effect and safety profile when administered to patients under the conditions specified in the labeling."(Leslie,2002 ; Joseph,1999)

2.1.7 Determining bioequivalence

The typical study design employed in bioequivalence studies is the two-treatment, two-period, crossover design (Figure 2.1 ). In this study design, subjects are randomly separated into two groups of equal number. The innovator formulation is administered to group 'A' in the first study period, and the test formulation is administered to group 'B' in the first period. During the second study period, group 'A' receives the test formulation and group 'B' receives the innovator formulation. The first and second study periods are separated by a washout period, which is designed to be of sufficient duration to allow elimination of the drug administered in the first period. Subjects are separated into two groups to allow identification of 'period' or 'sequence' effects in the study results.

Fig. 2.1. Schematic representation of the standard two-treatment crossover study design commonly employed in bioequivalence trials.

This procedure is usually carried out by calculating a 90% confidence interval which is constructed around the ratio of the test and reference by means of two one-sided test procedure.(95,96,98)To show bioequivalence, it requires 90% confidence interval limits in the range of 80-125% based upon logarithm transformed AUC and Cmax data.(95,96,98).This is commonly referred to as the 80%/125% "goalposts" for the average bioequivalence criterion and currently has been adopted by most of the drug regulatory bodies in the world.(91-93,95-99)


Ping CC, Bahari MB, Hassali MA. A pilot study on generic medicine substitution practices among community pharmacists in the State of Penang of Penang, Malaysia. Pharmacoepidemiol Drug Saf 2008; 17(1):82-89.

Hassali MA, Shafie AA. Price comparison between innovator and generic medicines sold by community pharmacists in the State of Penang. Journal of Generic Medicines 2008 (in press).

Birkett DJ,Mitchell AS,McManus P.Acost-effectiveness approach to drug subsidy and pricing in Australia. Health Aff 2001;20(3):pp104-14.

Dickson M.The priceing of pharmaceuticals: An international comparison. Clin Ther 1992;14(4),pp 604-610.

Donelan K,Blendon RJ,Schoen C,Davis K,Binns K.The cost of health system chang:public discontent in five nations.Health Aff 1999;18(3)pp.206-216.

Ess SM,Schneeweiss S,Szucs TD. European healthcare policies for controlling drug expenditure.Pharmacoeconomics 2003;21(2):pp.89-103.

Kanavos P.Financing pharmaceuticals in transition economies. Croat MedJ 1999;40(2):244-59.

King DR, Kanavos P .Encouraging the use of generic medicines: implications for transition economies. . Croat Med J 2002;43(4):462-9.

Moulds R: Generic prescribing - the pros. Australian Prescriber 1992, 15:50.

Nilsson JLG, Melander A. Use of generic drugs and effects of the reference price system in Sweden. Drug Inf J 2000;34(4):1195-1200.

Smeaton J. The generic market. Aust J Pharm 2000;81:pp 540-42.

Tatchel M.Controlling drug expenditure,. Aust J Pharm 2003;84:229.

Laing R,Hogerzeil H,Rooss-Degnan D. Ten recommendations to improve use of medicines in developing countries. Health Policy Plan 2001;16(1):pp.13-20.

Carroll NV.Impact of generic and therapeutic interchange incentives on community pharmacy.AM Pharm 1995;NS35(7):27-34.

Lofgren H. Generics drug: International trends and policy developments in Australia. Aust Health Rev 2004;27(1):pp.39-48.

Yarnall W. Generic substitution:therapeutic equivalence and cost containment. AM Druggist 1994;210:59-68.

Lieberman M. The essential guide to generic drugs. 1st ed.New york: Harper&Row;1986. p12.

Karim S,pillai G,Ziqubu-pageTT,CassimjeeMH,Morar MS. Potential savings from generic prescribing and generic substitution in south Africa. Health policy plan 1996;11(2):198-205..

Nuss P,Taylor D,DeHert M,Hummer M. The generic alternative in schizophrenia: opportunity or threat? CNS Drugs 2004;18(12):769-75.

Weaver L,Drug coast containment-the case for generics: Situation in the U.S.A. J Soc Admin pharm 1989;6(1):9-13.

Kirking DM,Ascione FJ,Gaither CA,Welage LS. Economics and structure of the generic pharmaceutical industry.J.AM pharm Assoc 2001;41(4):578-84.

Kirking DM,Ascione FJ. Perspectives on generic pharmaceutical:some conclusions.J AM Pharm Assoc 2001;41(6):826-8.

Generic drug. Wikipedia, the free encyclopedia. Accessed 15th October 2009.

Stevens A.Fogg S,Healy-north J, Hobbs M, Bell K, Tatchell M.Aqustion of generics,Aust J Pharm 1993;74:469-71.

McGavock H.Generic substitution:Issues relating to the Australia experience. Pharmacoepidemiol drug saf 2001;10(6):555-6.

Lofgren H, Boer R. Pharmaceuticals in Australia:developments in regulation and governance. Soc Sci Med 2004;58(12):2397-407.

Definition reference

World health organization. quality assurance of pharmaceutical: A Compendium of guidelines and related materials:volium 1.Geneva : World health organization;1997.P.65.

Jan Donovan: Is There a Role for Generic Medicines in the Pharmaceutical Benefits Scheme?, Health Issues, 2003, Number 75, pp. 9-11.

European Generic Medicines Association 2007, Facts and Figures What are Generics?, 19thOctober2009.

U.S. Food and Drug Administration. What are generic drugs? Available at: Accessed 13\2\2010.

Theraputics goods Administration (1994),"Australian Guidelines for registration of drug" VOL1, prescription and other specified drug product,2nd ed.,Australian Government printing service,Canberra.

Garattini L, Tediosi F. A comparative analysis of generics markets in five European countries. Health Policy. 2000 Apr; 51(3):149-62.

Generic name reference

4- Guidance in INN,2009 Available on WHO website at:

accessed 15th July 2009

5- Guidelines on the use of international non-proprietary names (INNs) for

pharmaceutical substances. WHO/PHARM S/NOM 1570. Avaiilable online


Accessed 15th July 2009

-Branded and generic medicines, Why do medicines sometimes have more than one name? 13th October 2009)

33-Kenagy J,Stein G. Naming,Labelling,and packaging of pharmaceuticals. Am J Health Syst Pharm 2001;58(21):3033-3041.

-Gundersen L.The complex process of naming drugs. Ann Intern Med1998;129(8),pp677-8.

Patent reference

-Melzer, David. Patent protection for medical technologies: Why some and not others? -Lancet, 1998, Vol. 351, Issue 9101

-Patent, Wikipedia, the free encyclopedia, ( Accessed 19th October2009.

- Lamarque V, Merle L, Demarez JP;.Generics and Substitution Modalities: Proposed Methods for the Evaluation of Equivalence, Traceability and Pharmacovigilance Reporting, Thérapie 2008 Juillet-Aout; 63 (4): 301-309. DOI: 10.2515/therapie:2008047(abstracte only)

- National Medicines Information Centre: generic prescribing (2009),VOL.15(1)

Reference international

-Steven Simoens and Sandra De Coster. (2006a)Sustaining Generic Medicines Markets in Europe, Research Centre for Pharmaceutical Care and Pharmaco-economics, April 2006 ,pp.86-91

- Generic medicine,2009. EurActiv_com - Generic Medicines EU - European Information on Health & Lifestyle.,accessed 7th October 2009.

Bioavailability reference

Bioavailability-definition and example

Leslie Z. Benet, 2002.Consideration of Polymorphism in Therapeutic Equivalence, accessed13th october2009.

Joseph P. Balthasar,1999. Bioequivalence and Bioequivalency TestingAmerican Journal of Pharmaceutical Education Vol. 63, Summer 1999.pp.194-198.

Walker R.B.; Kanfer I.; Skinner M.F. Bioequivalence assessment of generic products: an innovative south African approach.Clinical reaserch and regulatory affairs,2006;23(1),pp.11-20.