Objectives
At the end of this lab the students will be able to
Difene the biopharmaceutics
Known the in-vitro and in-vivo study
Stages of drug discovery
Biopharmaceutics
Biopharmaceutics and pharmacokinetics
are pharmaceutical disciplines useful to
improve the outcome of drug therapies, assist
drug product development, and establish
pharmacokinetics-pharmacodynamics models
and in vitro-in vivo correlations
Biopharmaceutics
can be defined as the study of the physical and
chemical properties of drugs and their proper
dosage as related to the onset, duration, and
intensity of drug action, or it can be defined as
the study of the effects of physicochemical
properties of the drug and the drug product, in
vitro, on the bioavailability of the drug, in vivo, to
produce a desired therapeutic effect.
Both definitions imply the relationship between
the physicochemical properties of the drug, the
drug's biological fate in the body after its
administration, and the resulting pharmacological
action of the drug.
The study of biopharmaceutics is based on
fundamental scientific principles and
experimental methodology .
Studies in biopharmaceutics use both in-vitro
and in-vivo methods.
In vitro is Latin for “in glass.” It describes medical
procedures, tests, and experiments that
researchers perform outside of a living organism.
An in vitro study occurs in a controlled
environment, such as a test tube
In vivo is Latin for “within the living.” It refers to
tests, experiments, and procedures that
researchers perform in or on a whole living
organism, such as a person, laboratory animal,
or plant.
New drugs, also known as drug candidates, undergo
in vitro testing before they enter clinical trials.
During an in vitro preclinical test, researchers will
expose target cells to a novel drug and monitor its
effects. In vitro testing is especially helpful for
identifying whether or not a novel drug has any toxic
or carcinogenic effects.
In vivo
Despite positive preclinical results, around 30% of
drug candidates fail human clinical trials due to
causing adverse side effects. An additional 60% do
not produce the desired effect.
In vivo testing, especially in clinical trials, is a vital
aspect of medical research in general. In vivo
studies provide valuable information regarding the
effects of a particular substance or disease
progression in a whole, living organism.
The main types of in vivo tests are animal
studies and clinical trials.
Animal studies
Researchers use animal studies to uncover the
mechanisms that underlie various disease
processes and to assess the safety of emerging
medical treatments.
Animal studies act as a kind of middle ground
between in vitro experiments and human trials.
Clinical trials
If a drug candidate appears both safe and effective
in in vitro and animal studies, researchers will
evaluate its effects in humans through clinical trials.
Researchers often compare the effects of new drugs
against those of a placebo.
Many consider randomized controlled trials (RCTs)
the gold standard for pharmaceutical testing. All
RCTs must include randomization and control.