Pharmaceutical Administration and Regulations in Japan - Nihs

information.
2.4) Studies concerning new indications,
new dosage regimens, etc.
Development of additional indications,
dose levels, dosage regimens,
administration routes, etc. requires new
protocols for both clinical and nonclinical
studies. Human pharmacology may also
be necessary for application.
2.5) Special considerations
Consideration should be given to
special circumstances and populations
when they are targeted as part of the
development plan.
(i) Studies of drug metabolites
The main metabolites must be
identified and detailed
pharmacokinetic studies performed.
The timing for studies to evaluate
metabolism is decided in
accordance with the characteristics
of the drug concerned.
(ii) Drug interactions
If a potential for drug interaction
is suggested by the metabolism
profile, by the results of nonclinical
studies or by information on similar
drugs, studies on drug interaction
are highly recommended. To
explore interaction with the drugs
that are frequently coadministered, it
Pharmaceutical Regulations in Japan:
is usually important that drug
interaction studies be performed in
nonclinical and, if appropriate, in
clinical studies.
(iii) Special populations
Some groups in the general
population may require special study
because they deserve unique
risk/benefit considerations, or
because they may need modification
of use of a drug or schedule of a
drug compared to general adult use.
Pharmacokinetic studies in
patients with renal and hepatic
dysfunction are important to assess
the impact of the potentially altered
drug metabolism or excretion.
Other special populations are as
follows:
(1) Elderly.
(2) Ethnic populations.
(3) Pregnant women.
(4) Nursing women.
(5) Children.
(iv) Microdose studies
Clinical studies to obtain
information on pharmacokinetics of
the investigational product in
humans and desired information at
the preclinical stage in development
candidate screening studies based
on pharmacokinetic information. A
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