Small Animal Clinical Pharmacology - CYF MEDICAL DISTRIBUTION

CHAPTER 1 PRINCIPLES OF CLINICAL PHARMACOLOGY
Regulatory review
Regulatory evaluation of submissions in support of a
new animal drug is a multidisciplinary activity, involving
chemists, toxicologists, environmental scientists,
clinically trained veterinarians and sometimes epidemiologists
and other skills. The review may take 1–2 years
or longer, depending on the novelty of the product and
completeness or complexity of the data evaluated.
Among the critical elements of the review is the generation
of the labeling of the product (described below)
and a decision as to the availability of the drug, particularly
if the product should be available only from veterinarians
or be obtained from pharmacists or more
readily available without restriction over-the-counter
(OTC). This important decision involves a balancing of
risks and benefits and comprises a number of criteria
that vary from country to country but generally include
the following considerations:
● the ability to prepare adequate labeling instructions
for nonprofessional use
● the potential for abuse, particularly for drugs of
addiction
● the potential for misuse, e.g. anabolic steroids,
which may have illicit uses in humans
● the safety of the drug in the target species
● the safety of the drug in humans
● the seriousness of side effects
● the need for further information and evaluation of
safety and efficacy
● the nature of the indications (disease being treated)
and the need for professional diagnosis and
monitoring
● the route and complexity of administration (e.g. is
special or sophisticated equipment or skill
necessary)?
● other public health considerations, e.g. impact of
use of a new antimicrobial agent on microbial
resistance and its transfer to human pathogens.
Once all issues are resolved and the regulatory agency
is satisfied with the safety, efficacy, quality and labeling
of the proposed product, the application is approved
and marketing can commence.
Pharmacovigilance/postmarketing
experiences
For those few new products that are commercialized,
study, data collection and analysis continue in order to
ensure that important new information on safety and
efficacy is not overlooked. During the development of
new animal drugs only small numbers of treated animals
(generally fewer than 2000) are closely monitored. Consequently,
unusual or rare manifestations of toxicity
may not be encountered. Only after marketing, when
large numbers of animals receive the treatment, is there
an opportunity to seek this information. On the basis
of postmarketing surveillance, high-risk groups may be
identified and product label details amended accordingly
to ensure continued safe use.
LABELING OF DRUGS
The labeling of a drug product is a legal document
and provides critical information permitting proper use
of the product. It includes all the information presented
on the immediate label, outer packaging and any
package inserts and consumer information leaflets.
Label information is based on the findings of the multitude
of studies undertaken during the development of
the drug and any additional experience gained after
approval.
The importance of familiarity and understanding of
the content of labeling information is underscored by a
recognition that it is frequently illegal (in some cases
even for veterinarians) to use a product in a way that is
inconsistent with the directions presented on the label.
Apart from the importance of legal responsibilities, the
information on the label should be sufficient to allow
the effective and safe use of the product for the approved
indications.
Labels contain a large amount of information that is
frequently presented poorly, both with respect to font
size and clarity of layout and expression. There is no
standard label presentation and data requirements for
inclusion on labels vary widely both within a country
(e.g. there are differences between pesticide labels, OTC
labels and veterinarian-only labels) and between countries.
Nevertheless, it is an important responsibility of
the prescriber and user to be completely familiar with
the labeling details before use of a product.
Information that typically is presented on a label
includes the following. However, veterinarians should
be familiar with the labeling requirements of their own
jurisdictions. Many of the label requirements as well as
copies of labeling information can be accessed via the
regulatory web addresses previously presented.
● Signal heading. A prominent statement that indicates
if the product is scheduled or controlled or available
only by prescription. Examples of signal headings
include ‘PRESCRIPTION ANIMAL REMEDY’ or
‘Caution. Federal law restricts this drug to use by or
on the order of a licensed veterinarian’. Other components
of the heading may be related to the safety
of the product (CAUTION, POISON, DANGER-
OUS POISON, CONTROLLED DRUG) and exposure
of children (KEEP OUT OF REACH OF
CHILDREN).
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