Pharmaceutical Administration and Regulations in Japan - Nihs

(1) Human pharmacology studies
(2) Therapeutic exploratory studies
(3) Therapeutic confirmatory studies
(4) Therapeutic use studies
Objectives and types of studies in
these four categories are listed in Table 5
(Classification of Clinical Studies
According to Objectives).
Studies must be designed and data
analyzed or evaluated according to the
above clinical guideline. Fig. 10
(Correlation between Development
Phases and Types of Study) illustrates
the close but variable correlation between
the two classification systems. The
distribution of the circles, open circles and
shaded circles, in the figure shows that
the types of study do not automatically
define the phases of development.
Clinical development is ideally a
step-wise process in which information
from small early studies is used to support
and plan later larger, more definitive
studies. To develop new drugs
efficiently, it is essential to identify
characteristics of the investigational
product in the early stages of
development and to plan appropriate
development based on this profile.
(i) Phase I (typical study: clinical
pharmacology)
Pharmaceutical Regulations in Japan:
Phase I entails the initial
administration of an investigational
new drug to humans. The most
typical study is that on clinical
pharmacology. Although clinical
pharmacology studies are typically
identified with Phase I, they may
also be indicated at other points in
the development sequence.
Studies conducted in Phase 1
typically involve one or a
combination of the following aspects:
(1) Estimation of initial safety and
tolerability
(2) Characterization of
pharmacokinetics
(3) Assessment of
pharmacodynamics
(4) Early assessment of efficacy
As a reference, the basic
concepts concerning the study items
and conduct of all clinical
pharmacokinetic studies for the
purpose of drug development are
given in Notification No. 796 of the
Evaluation and Licensing Division,
PMSB dated June 1, 2001 entitled
“Clinical Pharmacokinetic Studies on
Drugs.”
(ii) Phase II (typical study: therapeutic
exploratory)
Phase II is usually considered to
be the phase in which studies with
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