Physicians' Views on Generic Medicines: A Narrative Review

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Mohamed Azmi Hassali, Asrul Akmal Shafie, Ahmed Awaisu, Mohamed Izham Ibrahim, Chong Chee Ping and ShaziaPhysicians' Views on Generic Medicines: A Narrative Review

  

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Original Article

Physicians ’ views on generic medicines: A narrative review Received (in revised form): 27 th April 2009

Mohamed Azmi Hassali graduated with a pharmacy degree from the Universiti Sains Malaysia (USM), Malaysia in 1998. Following his pharmacy pre-registration training at Hospital Teluk Intan, Perak, he undertook his Master ’ s studies in the fi eld of clinical pharmacy at USM and graduated in 2000. In 2006, he was successfully awarded a PhD degree from the Victorian College of Pharmacy, Monash University, Melbourne in the fi eld of pharmacy practice. His current research interests are in the areas of clinical pharmacoeconomics, social pharmacy and the pharmacists ’ role in public health. Currently, Dr Azmi is attached to the Discipline of Social & Administrative Pharmacy, School of Pharmaceutical Sciences, USM.

Asrul Akmal Shafi e graduated with a pharmacy degree from the Universiti Sains Malaysia (USM), Malaysia in 2001 and was registered as a professional pharmacist in Malaysia in 2002. He was awarded USM fellowship in 2003 to pursue a doctorate degree in pharmacoeconomics, which he successfully completed at Cardiff University, United Kingdom in 2007. During this time, he also undertook a postgraduate diploma in Health Economics at the University of Glamorgan. His current research interests are in the area of health economics, and social and administrative pharmacy. Currently, Dr Shafi e is attached to the Discipline of Social & Administrative Pharmacy, School of Pharmaceutical Sciences, USM.

Ahmed Awaisu obtained a BPharm degree from Ahmadu Bello University Zaria, Nigeria in 1999 and a MPharm (Clin Pharm) degree from Universiti Sains Malaysia (USM) in 2004. He is an erstwhile lecturer in the Faculty of Pharmacy at the International Islamic University Malaysia and currently a doctoral degree candidate in the School of Pharmaceutical Sciences at USM. His research interests include clinical and outcomes research in cardiology and infectious diseases; evidence-based therapeutics; pharmacoepidemiology; health promotion and disease prevention; and pharmaceutical education. He has published extensively in the areas of clinical pharmacy, pharmacy practice and education in reputable international journals. He is also a recipient of a number of publication, research and scholarship awards.

Mohamed Izham Ibrahim is a professor of social and administrative pharmacy in the School of Pharmaceutical Sciences at Universiti Sains Malaysia. He obtained his BPharm degree from USM in 1991 and a PhD from University of Philadelphia in 1995. Izham has over 15 years of teaching experience and has successfully supervised more than 30 MSc and PhD students. His areas of research interest are pharmaceutical economics, drug policy & management, pharmacoepidemiology, social & behavioral aspects of pharmacy and health. He has published many books and research papers in international journals.

Chong Chee Ping is an academic staff training fellow and a PhD candidate in the Discipline of Clinical Pharmacy, School of Pharmaceutical Sciences, Universiti Sains Malaysia (USM). He graduated with a BPharm degree and an MPharm (Clin Pharm) degree from USM in 2002 and 2005, respectively. He was awarded a USM fellowship to pursue a doctorate degree in 2006, which he is currently undertaking. His current PhD project involves a comparative study investigating the perceptions of various health-care professionals on generic medicines in Malaysia and Australia. He has published a number of papers in impact factor journals.

Correspondence: Mohamed A.A. Hassali Discipline of Social & Administrative Pharmacy, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia E-mail: [email protected]

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Physicians’ views on generic medicines

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INTRODUCTION Most nations demand similar things from their health-care systems: effective services that improve the health and quality of life of their citizens, equitable access to those services, and effi cient use of resources. 1,2 A recent trend common to most nations is the rapid growth in expenditure for prescription drugs. 1,3,4 Efforts to control health-care costs, a major priority in many countries, have produced some interesting shifts in strategy. 1,2 These paradigm shifts do not only focus on limiting government spending on health, but also include some measures to involve citizens and health-care professionals in cost-sharing and cost-reducing mechanisms. Within this policy environment, generic medicines play an important role as an alternative to branded innovator medicines in the treatment of diseases. The cost savings that result from generic medicines can be used to purchase

newer, more effective medicines where they exist. 5 Different countries have historically taken diverse approaches related to generic medicines. Some countries like Austria have drawn on supply-side policies related to pricing and reimbursement to develop their generic medicines market, whereas others such as Denmark, Germany and United Kingdom have chosen demand-side policies related to generic substitution by pharmacists, and physician budgets, respectively. 2 However, there is no single approach towards developing generic medicines market in a given country.

Drug prescribing around the world is the prerogative of a number of health-care professionals – from physicians to physician assistants to nurse practitioners, depending on prescribing rights available in respective countries. However, physicians are traditionally the dominant prescribing health

Shazia Jamshed is a doctoral research fellow in the Discipline of Social & Administrative Pharmacy, School of Pharmaceutical Sciences, Universiti Science Malaysia. She graduated with a BPharm, MPharm and MPhil (Pharmacology) degrees from the University of Karachi, Pakistan. She has over 10 years of teaching and research experience with a reasonable number of publications. For the PhD, she is currently working on generic medicines issues in Pakistan.

ABSTRACT Most countries are facing escalating health-care expenditures. A recent trend to control these staggering increases in costs is to encourage the use of generic medicines. Physicians are at the centerpiece of the medication use process as they are the dominant prescribers in all clinical settings. It is therefore prudent to examine what they perceive about generic medicines. The current study attempts to identify and review the literature on physicians ’ perceptions and practices on the use of generic medicines. Using subject-related keywords, an extensive literature search was undertaken through indexing services available in the authors ’ institution ’ s library. Full text papers written in English language between 1980 and 2008 were retrieved and reviewed. Fourteen studies, majority ( n = 5) from the United States were reviewed and included. Most of the studies used quantitative methodology. Generally, physicians were neutral to slightly supportive on the use of generic medications. Most of the studies reviewed highlighted the factors that can infl uence physicians ’ views as policy-related issues, patient-related variables, drug characteristics and physician-related variables. Although physicians accept generic substitution under policy and economic pressures, they still have concerns about the overall quality and reliability of generic drugs as well as generic interchange of certain drug categories. Journal of Generic Medicines (2010) 7, 30 – 39. doi: 10.1057/jgm.2009.32 ; published online 1 September 2009

Keywords: generic medicines ; generic prescribing ; generic substitution ; perceptions ; physicians ; review

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professionals. 2 Therefore, physicians play a pivotal role in promoting and implementing the practice of generic prescribing and substitution. Prescribing lower costs generic medicines is recognized as a good prescribing practice and encouraged from an educational and cost-effectiveness point of view. 3,4,6

To the best of our knowledge, there is no published systematic or narrative review investigating the perceptions of physicians on generic medicines prescribing and substitution. Therefore, in order to get a better understanding on areas of agreement and disagreement held by physicians around the world on the concepts of generic prescribing and substitution, this narrative review was undertaken. In this article, we provide a chronological literature review on physicians ’ perceptions, experiences, and opinions towards generic medicines prescribing and use.

METHODS A literature search was performed from September to November 2008 to identify published studies on the views of physicians on generic medicines. The search strategy involved the use of Boolean connectors for combination of the terms ‘ generic ’ , ‘ brand ’ , ‘ multisource ’ , ‘ medications ’ , ‘ medicines ’ , ‘ drugs ’ , ‘ pharmaceuticals ’ and ‘ physicians ’ , ‘ general practitioners (GPs) ’ , and ‘ prescribers ’ . Equivalent terms in thesauruses or Medical Subject Headings browsers were used whenever possible. The search was limited to full text articles published in English language from 1980 until November 2008. Studies that measured physicians ’ perceptions on specifi c generic medicines or in specifi c disease conditions were excluded from this review. Studies that used aggregated data on prescribing were also excluded from this review. Electronic databases searched were those available in the authors ’ institution ’ s library and included: PubMed, Inside Web, ISI Web of Knowledge, Science Direct, Springer Link, Proquest, Ebsco Host and Google Scholar. This was supplemented by a

hand search of the reference lists of the retrieved articles and those that could be retrieved in full text were included. Identifi ed reports were sorted chronologically starting from 1980. The year 1980 was our starting point because we could not retrieve any full text papers before then.

Two hundred and nineteen titles and abstracts were identifi ed from the electronic search of all the eight databases and hand search. Subsequently, 159 titles and abstracts not related to physicians ’ views on generic medicines and duplicated citations were identifi ed and excluded. The full texts of 60 articles were retrieved for further evaluation. Lastly, 44 out of the 60 articles were excluded for further analysis as they only measured views on effi cacy of selected generic drugs used in specifi c disease conditions. The quorum fl ow chart for selection in this review is shown in Figure 1 .

Description of the studies included Eighteen studies were identifi ed, but fi ve studies 7 – 11 were excluded as they used aggregated data on prescribing rather than directly eliciting physicians ’ views. Subsequently, 14 published studies were included in the review (see Table 1 for more details). Of this, the majority ( n = 5) were from the United States, 12 – 16 and the rest from other countries of the world: one each from Australia, 17 Finland, 18 Malaysia, 19 Slovenia, 20 France, 21 Ireland, 22 United Kingdom 23 and Jamaica. 24 All the studies, except three 17 – 19 used quantitative methodology in exploring physicians ’ perceptions and experiences about generic medications. Further, all the studies, except two, 19,24 were conducted in developed nations. Six of the studies were directed to GPs, 17,20 – 23,25 one study involved family physicians, 13 and another study targeted resident physicians. 14 The rest of the studies 12,15,16,18,19,24 were directed to physicians, irrespective of their medical specialty. In addition, two studies, 12,21 reported their outcomes in the form of econometric models that explained factors affecting prescribing decisions by

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physicians, whereas most of the studies used descriptive and / or inferential statistics in reporting beliefs, knowledge and attitudes of physicians towards generic drugs 13 – 16,18 – 20,22 – 25 . The review also identifi ed two studies which utilized full qualitative methodology 17,18 and one study that used mixed methodology in reporting the results. 19

Methodological quality The retrieved literature was abstracted using a standardized data abstraction form in a table format containing most of the elements presented in Table 1 and our selection criteria. Each study was reviewed by all the six authors and a consensus meeting was convened to ensure quality assurance. The most prominent pitfall identifi ed was that the studies were restricted to certain geographical areas, provinces or states in which the results could not be generalized to the whole country of study. Three studies suffered

from inadequate sampling technique, 14,16,18 where convenience sampling and panel design, which might have an impact on generalization were used. Two studies suffered from self-report bias owing to dependence on physicians to report their recognition of drugs ’ names and dispensed drug data, respectively. 13,22 One study was supported by a brand name industry, which implied caution about its fi ndings. 15

RESULTS Generally, physicians were neutral to slightly supportive on the use of generic medications. However, the extent of their neutrality and acceptance varied substantially with several factors that can be summarized in the following main categories: policy-related issues, patient-related variables, drug characteristics and physician-related variable. Each of these categories is briefl y discussed in a narrative way below.

Titles and abstracts identified by electronic search of all nine databases and wherever possible review of the reference lists (n = 219)

Full text of articles retrieved for further assessment (n = 60)

Titles and abstracts not related to physicians’ views on generic medicines and duplications (n =159)

Studies related to physicians’ views on generic medicines which fulfill the selection criteria are included in the review (n = 14)

Articles not really assessing physicians’ views on generics, but targeting at the clinical efficacy and safety of generic medicines used in certain diseases or using aggregated data on prescribing (n = 46)

Figure 1 : Quorum fl ow chart of the review process.

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Tab

le 1

: A

sum

mar

y of

the

stu

dies

incl

uded

in t

he r

evie

w in

vest

igat

ing

phys

icia

ns ’ p

erce

ptio

n of

gen

eric

med

icin

es

Stud

y Co

untr

y M

etho

ds

Part

icipa

nts

Out

com

es

Lim

itatio

ns

Bear

den

and

Mas

on

(198

0)

USA

M

ail s

urve

y 41

8 ph

ysic

ians

R

esul

ts r

evea

led

that

con

fi den

ce in

reg

ulat

ion,

pot

entia

l sav

ings

, and

im

pact

s on

med

icin

e re

sear

ch r

epre

sent

rea

sona

ble

dete

rmin

ants

of

phy

sici

an p

refe

renc

e of

gen

eric

med

icin

es.

Stud

y w

as d

one

in o

nly

one

unsp

ecifi

ed

stat

e an

d th

e se

ttin

g w

as n

ot w

ell

desc

ribe

d.

Bow

er a

nd B

urke

tt

(198

7)

USA

M

ail s

urve

y 31

7 fa

mily

pr

actic

e ph

ysic

ians

The

maj

ority

(62

.5 %

) of

the

res

pond

ents

rep

orte

d th

at t

hey

had

enou

gh c

onfi d

ence

to

pres

crib

e ge

neri

c m

edic

ines

reg

ular

ly b

ut

only

26.

9 % in

dica

ted

that

the

y ac

tual

ly p

resc

ribe

d m

ostly

gen

eric

s.

The

gen

eric

pre

scri

bing

was

mor

e co

mm

on a

mon

g fa

mily

phy

sici

ans

who

wer

e re

side

ncy

trai

ned

and

who

rel

ied

leas

t on

dru

g co

mpa

ny

repr

esen

tativ

es fo

r in

form

atio

n on

new

med

icin

es, a

nd b

eing

a

read

er o

f the

New

Eng

land

Jour

nal o

f Med

icin

e.

Pres

ence

of d

iffer

ence

s be

twee

n re

spon

dent

s an

d no

n-re

spon

dent

s w

ith r

espe

ct t

o th

e va

riab

les

stud

ied.

The

stu

dy’s

dep

ende

nce

on r

espo

nden

ts t

o te

st t

heir

ow

n ab

ilitie

s to

rec

ogni

ze t

he n

ames

of

pres

crip

tion

drug

s.

Tily

ard

et a

l (19

90)

New

Zea

land

M

ail s

urve

y 20

0 G

Ps

Mos

t of

the

res

pond

ents

(67

% )

activ

ely

pres

crib

ed g

ener

ic m

edic

ines

. A

bout

52 %

of G

Ps w

ere

oppo

sed

to p

harm

acis

ts ’ g

ener

ic

subs

titut

ion

and

thei

r vi

ews

wer

e in

fl uen

ced

by t

he p

roof

of

gene

ric

bioe

quiv

alen

ce a

nd c

ost

savi

ng. A

nd 7

0 % in

dica

ted

that

pa

tient

s ’ g

ener

ic m

edic

ine

use

was

bec

ause

of t

he G

Ps c

hoic

e.

Smal

l sam

ple

size

and

sam

plin

g te

chni

que

was

not

wel

l des

crib

ed.

Shul

kin

et a

l (19

92)

USA

M

ail s

urve

y 63

res

iden

t ph

ysic

ians

M

ost

of t

he r

espo

nden

ts (

73 %

) be

lieve

d th

at g

ener

ic a

nd b

rand

nam

e m

edic

ines

wer

e eq

ually

effe

ctiv

e. S

ome

diffe

renc

es b

y sp

ecia

lty

wer

e se

en: f

or in

stan

ce, p

sych

iatr

y re

side

nts

wer

e m

ore

likel

y th

an

surg

ery

or in

tern

al m

edic

ines

res

iden

ts t

o pr

escr

ibe

bran

d na

me

med

icin

es.

Sam

plin

g te

chni

que

(con

veni

ence

sa

mpl

ing)

and

sm

all s

ampl

e si

ze.

Tur

nbul

l and

Pa

rson

s (1

993)

U

K

Res

earc

her

adm

inis

tere

d su

rvey

39 G

Ps

The

phy

sici

ans ’

att

itude

s to

war

ds g

ener

ic m

edic

ines

dep

ende

d on

va

riou

s pr

oduc

t fe

atur

es, n

amel

y, t

he t

hera

peut

ic c

ateg

ory

and

dosa

ge fo

rm c

ompl

exity

. The

att

itude

s al

so v

arie

d am

ong

diffe

rent

ph

ysic

ians

’ pra

ctic

e ch

arac

teri

stic

s. P

hysi

cian

s w

ho w

orke

d al

one

had

an a

vers

ion

to g

ener

ic p

resc

ribi

ng. T

he p

hysi

cian

s w

ith h

ighe

r nu

mbe

r of

yea

rs p

ract

isin

g in

gen

eric

pra

ctic

e w

ere

mor

e in

clin

ed

to p

resc

ribe

bra

nd n

ames

.

The

sam

plin

g po

pula

tion

rest

rict

ed t

o a

smal

l geo

grap

hic

area

, sam

plin

g te

chni

que

(con

veni

ence

sam

plin

g)

and

smal

l sam

ple

size

.

Bana

han

and

Kol

assa

(1

997)

U

SA

Mai

l sur

vey

396

phys

icia

ns

Phys

icia

ns w

ere

clas

sifi e

d in

to p

ro-s

ubst

itutio

n (4

3.2 %

) an

d an

ti-su

bstit

utio

n gr

oups

(56

.8 %

). T

he p

ro-s

ubst

itutio

n an

d an

ti-su

bstit

utio

n gr

oups

wer

e si

gnifi

cant

ly d

iffer

ent

with

res

pect

to

bel

iefs

abo

ut a

nd e

xper

ienc

es w

ith g

ener

ics

and

know

ledg

e of

th

e FD

A b

ioeq

uiva

lenc

y st

anda

rd. O

nly

17 %

of p

hysi

cian

s co

rrec

tly

iden

tifi e

d th

e FD

A s

tand

ards

for

bioe

quiv

alen

cy.

The

stu

dy w

as s

uppo

rted

by

gran

t fr

om a

bra

nd n

ame

indu

stry

.

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Physicians’ views on generic medicines

35

McG

ettig

an e

t al

(199

7)

Irel

and

Mai

l sur

vey

107

GPs

Se

vera

l fac

tors

con

trib

uted

to

low

gen

eric

pre

scri

bing

am

ong

the

Iris

h ph

ysic

ians

. The

phy

sici

ans

wer

e co

ncer

ned

abou

t th

e re

liabi

lity

or q

ualit

y of

gen

eric

pro

duct

s, p

ossi

ble

lega

l lia

bilit

ies

asso

ciat

ed

with

gen

eric

s us

e an

d th

e fa

ct t

hat

phar

mac

ists

may

dis

pens

e m

ore

expe

nsiv

e pr

opri

etar

y pr

epar

atio

ns in

the

cas

e of

pri

vate

pr

escr

iptio

ns w

ritt

en g

ener

ical

ly.

Sam

ple

size

was

sm

all a

nd m

ay n

ot b

e re

pres

enta

tive

of G

Ps in

the

cou

ntry

.

Para

pona

ris

et a

l (2

004)

Fr

ance

M

ail s

urve

y 60

0 G

Ps

Thi

s st

udy

eval

uate

d fa

ctor

s ex

plai

ning

GPs

’ will

ingn

ess

to p

resc

ribe

in

inte

rnat

iona

l non

-pro

prie

tary

nam

es (

INN

). N

earl

y 76

% o

f th

e re

spon

dent

s in

dica

ted

that

the

y w

ere

will

ing

to w

rite

the

ir

pres

crip

tions

usi

ng IN

N. T

he G

Ps w

ere

less

rel

ucta

nt t

o pr

escr

ibe

INN

w

hen

they

hav

e hi

gh w

orkl

oads

, reg

ular

ly u

se p

ract

ice

guid

elin

es, p

ay

for

med

ical

jour

nals

, hav

e a

pers

onal

com

pute

r to

get

dis

tant

ele

ctro

nic

mat

eria

ls o

r ha

ve s

ome

activ

ities

in a

hos

pita

l or

heal

th c

entr

e.

The

dat

a w

ere

colle

cted

from

one

pr

ovin

ce, t

hus

the

gene

raliz

abili

ty o

f th

e re

sults

is li

mite

d.

Barr

ett

(200

5)

USA

W

eb-b

ased

sur

vey

425

phys

icia

ns

The

maj

ority

of t

he p

hysic

ians

(95 %

) sup

port

the

use

of g

ener

ic s

ubst

itute

s fo

r br

and

nam

e m

edic

ines

whe

n th

ey a

re a

vaila

ble

and

appr

opria

te fo

r th

e pa

tient

s. Ph

ysic

ians

say

that

they

feel

pre

ssur

ed b

y pa

tient

s (6

9 % ),

heal

th-

care

pla

ns o

r in

sura

nce

com

pani

es (9

1 % ) t

o pr

escr

ibe

gene

ric d

rugs

.

Onl

ine

sam

ples

are

lim

ited

to o

nly

thos

e w

ho p

artic

ipat

ed in

the

re

sear

ch. H

ence

, the

re a

re p

oten

tials

fo

r no

n-re

spon

se e

rror

.

K

ersn

ik a

nd P

elka

r (2

006)

Sl

oven

ia

Mai

l sur

vey

117

GPs

A

bout

38 %

of t

he G

Ps d

id n

ot ta

ke p

rice

into

con

sider

atio

n w

hen

pres

crib

ing

med

icin

es. N

early

89 %

of t

he G

Ps p

erce

ived

gen

eric

s to

hav

e eq

ual e

ffect

iven

ess

as b

rand

nam

e m

edic

ines

. One

qua

rter

of t

he G

Ps

wou

ld p

resc

ribe

mor

e ge

neric

s if

addi

tiona

l clin

ical

tria

ls w

ere

avai

labl

e.

Abo

ut 1

6 % o

f the

res

pond

ents

thou

ght t

hat t

he p

harm

aceu

tical

indu

stry

ha

d a

huge

infl u

ence

on

thei

r pr

escr

ibin

g pa

tter

ns.

Ran

dom

izat

ion

met

hod

not

wel

l el

ucid

ated

.

De

Run

and

Fel

ix

(200

6)

Mal

aysi

a In

-dep

th in

terv

iew

s an

d se

lf-ad

min

iste

red

surv

ey

15 h

ospi

tal-b

ased

ph

ysic

ians

(in

terv

iew

ed in

th

e fi r

st p

hase

) an

d 62

phy

sici

ans

from

the

sam

e in

stitu

tion

answ

ered

a

ques

tionn

aire

Thi

s st

udy

dete

rmin

ed p

erce

ptio

ns o

f phy

sici

ans

in a

pub

lic h

ospi

tal

tow

ards

pat

ente

d an

d ge

neri

c m

edic

ines

. The

res

pond

ents

vie

wed

pa

tent

ed m

edic

ines

as

supe

rior

in q

ualit

y, e

ffi ca

cy a

nd s

afet

y.

Gen

eric

med

icin

es w

ere

perc

eive

d as

mor

e af

ford

able

, but

lack

of

qual

ity c

ontr

ol a

nd u

ncer

tain

effi

cacy

. Fac

tors

tha

t af

fect

phy

sici

ans ’

pr

escr

ibin

g de

cisi

ons

incl

ude

thei

r ow

n ex

peri

ence

, lite

ratu

res,

pa

tient

affo

rdab

ility

and

hos

pita

l pol

icy.

Dat

a w

ere

colle

cted

from

one

pr

ovin

ce, t

hus

the

gene

raliz

abili

ty

of t

he r

esul

ts is

lim

ited.

Bia

ses

from

ex

peri

ence

of r

espo

nden

ts c

ould

ha

ve a

ffect

ed t

he r

elia

bilit

y of

the

fi n

ding

s.

Has

sali

et a

l (20

06)

Aus

tral

ia

Sem

i-str

uctu

red

qual

itativ

e in

terv

iew

10 G

Ps

The

res

pond

ing

GPs

hav

e m

ixed

att

itude

s to

war

d ge

neri

cs p

resc

ribi

ng.

The

re w

ere

GPs

who

vie

wed

gen

eric

s as

equ

ally

effe

ctiv

e as

the

in

nova

tor

bran

ds. S

ome

GPs

wer

e di

ssat

isfi e

d w

ith t

he g

ener

ic

subs

titut

ion

polic

y be

caus

e th

eir

pers

onal

rol

e as

pre

scri

ber

is b

eing

th

reat

ened

by

the

phar

mac

ists

. The

re w

ere

conc

erns

abo

ut p

atie

nt

conf

usio

n ar

isin

g fr

om s

ubst

itutio

n. N

one

of t

he G

Ps k

new

the

bi

oequ

ival

ence

acc

epta

bilit

y cr

iteri

a fo

r ge

neri

c m

edic

ines

.

Stud

y w

as c

onfi n

ed t

o on

e st

ate

only

, so

the

fi nd

ings

can

not

be

extr

apol

ated

.

© 2010 Macmillan Publishers Ltd. 1741-1343 Journal of Generic Medicines Vol. 7, 1, 30–39

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36

Policy-related issues One of the factors related to the policy is knowledge of regulatory requirements imposed on generic drugs by regulatory authorities. In this context, the available data, 15,17 shows that physicians lack the knowledge of these requirements. Another factor is physicians ’ confi dence in regulatory authorities in ensuring the quality, safety and effi cacy of generic drugs. Although this confi dence was seen as an important determinant for supporting generics by physicians, 12 it differed across countries, 15,17 and within the same country over time.

Besides requirements imposed by regulatory authorities, physicians also found that specifi c provision of health-care fi nancing plan do have an impact on the utilization pattern for generic by physicians. 16

Patient-related factors Physicians ’ prescribing decision was seen to be the result from essentially their own decision-making process. However, a certain proportion of this decision can be explained by patient-related variables. These variables include feelings that they can contribute to consumers ’ saving on drugs by prescribing generically. 12,15 – 19,24

Drug-related factors Being cheaper than their branded counterparts raised the concerns of the physicians about their quality, safety and effectiveness, especially in the presence of heavy and successful promotional activities from brand name industry. 16,19,20 These concerns faded in many drug classes, but strengthen in a few classes which are considered by physicians to be critical dose drugs. 15,18 The issues also stem from the exceptional situation of prescription drugs, where drug companies know more about their drugs than the professionals who prescribe them. Another issue that deserves mention is the source of information about drugs that is available to physicians. Most studies found that physicians are exposed to biased and unbalanced T

able

1 C

ontin

ued

Stud

y Co

untr

y M

etho

ds

Part

icipa

nts

Out

com

es

Lim

itatio

ns

Hei

kkila

et a

l (20

06)

Finl

and

Stru

ctur

ed

qual

itativ

e in

terv

iew

s

49 p

hysi

cian

s T

he m

ajor

ity o

f phy

sici

ans

(86 %

) w

ere

satis

fi ed

with

gen

eric

su

bstit

utio

n po

licy.

The

mai

n re

ason

men

tione

d fo

r su

bstit

utio

n w

as

cost

sav

ing.

Aro

und

half

of t

he p

hysi

cian

s th

ough

t in

terc

hang

eabl

e m

edic

ines

in c

erta

in m

edic

ine

grou

ps a

re n

ot e

qual

ly e

ffect

ive

and

safe

.

Con

veni

ent

sam

plin

g te

chni

que,

thu

s th

e re

sults

can

not

be g

ener

aliz

ed t

o al

l Fin

nish

phy

sici

ans.

Gos

sell-

Will

iam

s (2

007)

Ja

mai

ca

Surv

ey a

dmin

iste

red

via

mul

ti ch

anne

ls

(e-m

ails

, fax

, fac

e-to

-face

inte

rvie

ws

and

by p

hone

)

60 p

hysi

cian

s A

roun

d 49

% o

f the

res

pond

ing

phys

icia

ns w

ere

mos

tly p

resc

ribi

ng

gene

ric

will

ingl

y. T

here

wer

e do

ubts

abo

ut w

heth

er b

ioeq

uiva

lenc

e of

a g

ener

ic w

as e

quita

ble

to t

hera

peut

ic e

quiv

alen

ce t

o in

nova

tor

med

icin

e. A

bout

33 %

of t

he p

hysi

cian

s ha

d ex

peri

ence

d cl

inic

al

prob

lem

s w

ith g

ener

ic s

ubst

itute

s th

at t

hey

perc

eive

d w

ould

not

ha

ve o

ccur

red

with

the

inno

vato

r.

Phys

icia

ns s

elec

ted

to p

artic

ipat

e in

th

e su

rvey

is li

mite

d to

the

ir li

stin

g in

loca

l dir

ecto

ry, h

ence

thi

s w

ill

incr

ease

the

pot

entia

l of

non-

resp

onse

bia

s.

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information about drugs from brand name companies, 19,20 and at the same time weak promotional activities from generic companies. 16

Physician-related factors Factors found to be related to physicians and their generic versus branded drugs prescribing decisions are socio-demographic factors, unobservable characteristics of physicians and the concern of legal liabilities in case of prescribing generic medicines. Socio-demographic characteristics of physicians studied include age, training level and type, time since graduation, specialty, fi eld experience, practice setting and caseload. Although some studies found some of these socio-demographic variables to be associated with prescribing generically, 13,19 one study found them to explain only a small percentage of prescribing decisions. 20

DISCUSSION Generally, the review suggests that physicians will resist generic practices at the beginning of introducing them, but this resistance will wane in the face of policy measures and economic pressures, but not to the extent of regular generic prescribing. The study has managed to contribute to the existing literature related to physicians ’ view on generic prescribing and substitution and what infl uences their decision making. However, there are a few limitations to the review. Notable among these is that the review was limited to studies published in English language only, which might have prevented us from including the work done in other languages. Another limitation is that the review was limited to full text papers retrieved from databases subscribed by our institution ’ s library.

In the late 1980s in the US drug market which is one of the earliest markets to introduce the concept of generic drugs, researchers and policy-makers were concerned about the acceptance of new legislations enacted to increase generics market share,

because health professionals showed substantial reluctance to generic prescribing and substitution. The view that was dominant was that generic drugs produced by small and unknown companies were less satisfactory than branded ones produced by well-known companies. 12 With time, regulatory measures taken in response to economic pressures and experience with generics have revolutionalized the resistance. These views and resistances therefore have changed and more physicians looked to generics as equivalents to branded drugs and started to accept generic alternatives and prescribed them willingly. 24 However, concerns and doubts persisted about this equivalency in certain drug categories 24 and prescribing by brand names continued to be the most prevalent practice. 12 – 15 In Britain, GPs showed a great deal of resistance to prescribing generics voluntarily until when policy measures were taken (introduction of black list which is not available through National Health Services fund-holding scheme), which forced GPs to prescribe by generic names. 23 Physicians from the rest of the countries reviewed here held similar opinions about generic prescribing and substitution to those held by their colleagues in countries where generic substitution was introduced earlier as narrated above. The most common opinions held by physicians from these countries are their concerns about the quality of generic drugs in comparison with branded ones and about the switchability of certain drug classes considered critical to these physicians. 17 – 22

CONCLUSION Although physicians accepted generic substitution under policy and economic pressures, they still have concerns about overall generic drugs ’ quality and reliability, and switchability of certain drug categories which differ from country to country. These concerns prevent the full adoption of generic drugs prescribing and substitution by physicians, which can lead to escalation in

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health-care costs either on the governments, insurers or consumers directly. In order to eliminate these concerns, there should be full cooperation between governments, educators, professional organizations and consumers associations: regulatory authorities through assuring that generics are produced and kept according to the required standards; educators through teaching the concepts and values of generic medicines and disseminating knowledge on the standards required to register generics; professional bodies through declaring their views from generic practices in their policy statements; and consumers ’ associations through demanding to be informed about the drugs they will pay for, especially in cases of out-of-pocket payments.

ACKNOWLEDGEMENTS This article is dedicated to late Mr Nabil Abdo Al-Gedadi who passed away peacefully earlier last year. Nabil was instrumental in devising the fi rst version of this manuscript and his sudden demise is a great loss to all the authors. This study received no specifi c grant from any funding agency in the public, commercial or not-for profi t sectors.

REFERENCES 1 . Kanavos , P . ( 1999 ) Financing pharmaceuticals in

transition economies . Croatian Medical Journal 40 (2) : 244 – 259 .

2 . Ess , S . M . , Schneeweiss , S . and Szucs , T . D . ( 2003 ) European healthcare policies for controlling drug expenditure . Pharmacoeconomics 21 (2) : 89 – 103 .

3 . Kirking , D . M . and Ascione , F . J . ( 2001 ) Perspectives on generic pharmaceuticals: Some conclusions . Journal of the American Pharmaceutical Association 41 (6) : 826 – 828 .

4 . Evers , P . ( 2001 ) Generics past, present and future . Pharmaceutical Times (October): 30 – 32 .

5 . King , D . R . and Kanavos , P . ( 2002 ) Encouraging the use of generic medicines: Implications for transition economies . Croatian Medical Journal 43 (4) : 462 – 469 .

6 . Hassali , M . A . , Kong , D . C . and Stewart , K . ( 2007 ) A comparison between senior medical students ’ and pharmacy pre-registrants ’ knowledge and perceptions of generic medicines . Medical Education 41 (7) : 703 – 710 .

7 . Hellerstein , J . K . ( 1998 ) The importance of the physician in the generic versus trade-name prescription decision . Rand Journal of Economics 29 (1) : 108 – 136 .

8 . Mott , D . A . and Cline , R . R . ( 2002 ) Exploring generic drug use behavior: The role of prescribers and pharmacists in the opportunity for generic drug use and generic substitution . Medical Care 40 (8) : 662 – 674 .

9 . Steinman , M . A . , Chren , M . M . and Landefeld , C . S . ( 2007 ) What’s in a name? Use of brand versus generic drug names in United States outpatient practice . Journal of General Internal Medicine [Brief Reports] 22 : 645 – 648 .

10 . Muijrers , P . E . , Janknegt , R . , Sijbrandij , J . , Grol , R . P . and Knottnerus , J . A . ( 2004 ) Prescribing indicators. Development and validation of guideline-based prescribing indicators as an instrument to measure the variation in the prescribing behaviour of general practitioners . European Journal of Clinical Pharmacology 60 (10) : 739 – 746 .

11 . Gill , P . S . and Roalfe , A . ( 2001 ) Determinants of prescribing costs amongst single-handed general practitioners . Journal of Clinical Pharmacy & Therapeutics 26 (6) : 433 – 435 .

12 . Bearden , W . O . and Mason , J . B . ( 1980 ) Determinants of physician and pharmacist support of generic drugs . Journal of Consumer Research 7 (2) : 121 – 130 .

13 . Bower , A . D . and Burkett , G . L . ( 1987 ) Family physicians and generic drugs: A study of recognition, information sources, prescribing attitudes, and practices . Journal of Family Practice 24 (6) : 612 – 616 .

14 . Shulkin , D . J . et al ( 1992 ) Generic versus brand name drug prescribing by resident physicians in Pennsylvania . American Journal of Hospital Pharmacy 49 (3) : 625 – 626 .

15 . Banahan 3rd , B . F . and Kolassa , E . M . ( 1997 ) A physician survey on generic drugs and substitution of critical dose medications . Archives of Internal Medicine 157 (18) : 2080 – 2088 .

16 . Barrett , L . L . ( 2005 ) Physicians ’ Attitudes and Practices Regarding Generic Drugs . Washington DC: AARP Knowledge Management , [updated 2005; cited 11 September 2008], pp. 1 – 33 , http://assets.aarp.org/rgcenter/health/phys_generic.pdf .

17 . Hassali , M . A . , Kong , D . C . M . and Stewart , K . ( 2006 ) Generic medicines perceptions of general practitioners in Melbourne, Australia . Journal of Generic Medicines 3 (3) : 214 – 225 .

18 . Heikkila , R . , Mantyselka , P . , Hartikainen-Herranen , K . and Ahonen , R . ( 2007 ) Customers ’ and physicians ’ opinions of and experiences with generic substitution during the fi rst year in Finland . Health Policy 82 (3) : 366 – 374 .

19 . De Run , E . C . and Felix , M . -K . N . ( 2006 ) Patented and generic pharmaceutical drugs: Perception and

© 2010 Macmillan Publishers Ltd. 1741-1343 Journal of Generic Medicines Vol. 7, 1, 30–39

at Universiti Sains Malaysia on December 13, 2011jgm.sagepub.comDownloaded from

Page 11

Physicians’ views on generic medicines

39

prescription . International Journal of Business and Society 7 (2) : 55 .

20 . Kersnik , J . and Peklar , J . ( 2006 ) Attitudes of Slovene general practitioners towards generic drug prescribing and comparison with international studies . Journal of Clinical Pharmacy and Therapeutics 31 (6) : 577 – 583 .

21 . Paraponaris , A . et al ( 2004 ) Delivering generics without regulatory incentives? Empirical evidence from French general practitioners about willingness to prescribe international non-proprietary names . Health Policy 70 (1) : 23 – 32 .

22 . McGettigan , P . , McManus , J . , O ’ Shea , B . , Chan , R . and Feely , J . ( 1997 ) Low rate of generic prescribing in the Republic of Ireland

compared to England and Northern Ireland: Prescribers ’ concerns . Irish Medical Journal 90 (4) : 146 – 147 .

23 . Turnbull , P . W . and Parsons , N . E . ( 1993 ) Generic prescribing in general medical practice: An attitudinal study of general practitioners . Marketing Intelligence & Planning 11 (4) : 30 .

24 . Gossell-Williams , M . ( 2007 ) Generic substitutions: A 2005 survey of the acceptance and perceptions of physicians in Jamaica . West Indian Medical Journal 56 (5) : 458 – 463 .

25 . Tilyard , M . W . , Dovey , S . M . and Rosenstreich , D . ( 1990 ) General practitioners ’ views on generic medication and substitution . New Zealand Medical Journal 103 (893) : 318 – 320 .

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