Asthma experts have called for a ban on the use

of preservatives such as the commonly used

benzalkonium chloride and the stabilizer ethyl-

enediamine tetra acetate (EDTA), in medications

because of links with increased airway obstruc-

tion in sufferers of asthma and chronic pul-

monary disease. A review of studies on the use

of medications with and without preservatives,

could not find any real benefit from their use in

terms of reducing bacterial contamination. The

researchers in these studies, including Leslie

Hendeles (University of Florida College of

Medicine, Gainesville, FL, USA), recently dis-

cussed the safety implications of these addi-

tives in nebulizer solutions, used to treat lung

dysfunction, and believe that, rather than

benefiting the patient and preventing infection,

they pose a substantial risk by constricting air-

ways and reducing the effectiveness of the

medication1.

Nebulizer solutions are used in the treatment

of asthma, emphysema and chronic bronchitis.

Researchers have found that the amount of

benzalkonium chloride contained in a standard

prescription vial actually leads to constriction of

the airways, counteracting the effects of the

medication and sometimes worsening lung

function in the patient; similar effects were re-

ported for EDTA when higher doses of the stabi-

lizer were inhaled. According to Hendeles, safer,

preservative-free medications are available in

sterile, single-dose vials and pharmacists, at

least in the USA, tend not to consider the pres-

ence of preservatives in a vial and (legally) dis-

pense preservative-containing and preservative-

free products as if they were equivalent – often

regardless of the specification of the prescribing

doctor. Alerted to the problem, the Florida State

Board of Pharmacy has drawn attention to the

issue in a newsletter, that was sent to pharma-

cists throughout the state.

The more common metered-dose inhalers,

which release salbutamol and/or corticosteroids,

do not include the preservatives and so, accord-

ing to the scientists, users are not at risk.

Reference01 Beasley, R. (1998) Pharmacotherapy 18, 130–139

update news PSTT Vol. 1, No. 3 June 1998

94

Concern over preservativesDavid Bradley, tel/fax: 144 1954 202218, Web: http://www.camsoft.com/elemental/

The stated aim of the book is to provide an

overview of the science and applications of

biopharmaceutical products. A tall order for

any single volume. It is targeted at under-

graduate and postgraduate students or em-

ployees in the industry seeking to gain a

wider perspective of the field.

Inevitably, given the scope and target mar-

kets, there are areas of lightweight coverage

and omission. However, the rationale for se-

lective coverage of topics is not always clear;

perhaps this represents the coverage of a re-

lated coursework programme. For example,

Chapter 3 detailing manufacturing processes

spans some 80 pages; biopharmaceutical

products present a complex set of problems

for manufacture, and it is understandable

that this section should be extensive. The sec-

tion detailing modern approaches to devel-

opment of pharmaceuticals extends to just

under 40 pages and this section incorporates

scant coverage of new drug discovery. This

itself should have warranted a separate

section, given the recent and on-going rev-

olution in advanced technologies such as

combinatorial chemistry, high-throughput

screening and genomics.

The sections focusing on therapeutic

agents themselves include extensive coverage

of cytokines, growth factors, hormones, blood

products and therapeutic enzymes, and anti-

bodies, vaccines and adjuvants. The book

focuses on peptide-based therapies, and the

major topics of nucleic acid therapeutics,

antisense and gene therapy are therefore

dealt with in a single brief chapter.

The author has managed to combine a

considerable amount of information in a sin-

gle volume to provide a useful, basic ground-

ing for the tyro. In particular, the sections on

development and manufacture (comprising

more than one-third of the content) give the

newcomer an understanding of the workings

of the product pipeline. This could have been

complemented by further discussion of the

research technologies in more basic research.

A short chapter on the corporate dynamics

of the pharmaceutical/biotechnology sector

in recent years could also have provided an

entertaining addition.

At the price, this book provides an informa-

tive introduction to the world of biopharma-

ceutical products and product workflow.

David Hughes

Copyright ©1998 Elsevier Science Ltd. All rights reserved. 1461-5347/98/$19.00.

Book reviewBiopharmaceuticals: Biochemistry and Biotechnology by Gary Walsh, John Wiley & Sons, 1998. £29.95 (xvi1431 pages) ISBN: 0 4719 7789 6