Biomedical Research Biomedical Research Definition Study of the

Biomedical Research

Biomedical Research • Definition • Study of the processes of life; the prevention and treatment of disease; and the genetic lifestyle and environmental factors related to disease and health

Types of biomedical research BASIC APPLIED CLINICAL

BASIC • Research conducted to increase fundamental knowledge • Not directed toward solving any particular problem

Basic • Focuses on understanding normal life processes and disease – Molecular – Cellular

BASIC • Provides building blocks for other types of research –is the first stage • Writing a research paper on a particular disease would be an example

APPLIED Directed toward specific objectives, such as the development of a new drug, treatment or surgical procedure

Applied • Conducted with: – – Animals (primarily) Tissue cultures Computer models And humans

Clinical • Usually last stage of medical research • Used when other forms of research have taken place – most clinical trials involve humans • Used to treat potential drugs and treatments in humans • Builds on what is done in basic and applied stages

CLINICAL • Takes place : – Hospital – Clinical setting for health care – Applies directly to: • Prevention, diagnosis, or treatment of a specific disease in the individual or group of individuals or the rehabilation of the individual

Clinical • Broad variety of activities and areas of study – Human clinical trials (Research study for a new medicine or treatment) – Psychosocial and behavioral research – Disease control research (Research study for a particular disease)

Clinical • Edward Jenner – – Inoculated son with cow pox 6 weeks later- exposed son to smallpox Son was resistant “immunization”

Biomedical Research Methods • 1. Chemical, mechanical, mathematical, and computer simulations • 2. In vitro tests • 3. Non-humans animal models • 4. Human Studies • 5. Epidemiological Studies

Strengths of Chemical, Mechanical, Mathematical, and Computer Simulations • 1. Computers increase speed and efficiency with which data is used and processed • 2. Pattern recognition programs enable scientists to compare characteristics of one compound to another

Strengths of Chemical, Mechanical, Mathematical, and Computer Simulations • 3. Can extrapolate data • A. From high – dose experimental exposure to low-dose • B. From animals to humans 4. Reduces the numbers of animals needed for research

Using Computers as a Research Method

Limitations of Chemical, Mechanical, Mathematical, and Computer Simulations • Limitations • 1. Cannot replace laboratory testing • 2. Computers do not generate data – they only process existing data • 3. Computers equipment and software is expensive

In Vitro Tests In Vitro – “in glass” Takes place in an artificial environment (Laboratory)

Strengths of In Vitro Studies • 1. Allow scientists to study a single effect in isolation • 2. Less expensive, less time, more accurate, and easier to control than in vivo (whole animal) systems

Strengths of In Vitro Studies • 3. More precise results as a result of ability to control temperature, acidity, oxygen levels and environmental conditions • 4. Critical to the study of viruses which grow only in living cells

Limitations of In Vitro Studies • 1. The time from chemcical exposure to toxic effect too complicated to be duplicated in vitro • (Cancer as a multistep process for example) • 2. Cells grown in cultures are not exposed to other functions taking place in a living organism

Limitations of In Vitro Studies • 3. Cells do not metabolize toxins in a culture the same way as in the whole body • 4. Difficult to maintain differentiated cells in a culture • 5. Cultures cannot tell us how a substance affects a complex system

Non-Human Animal Models • Animals provide the best known surrogate for humans in the lab • Similarities between animals and humans outweigh differences

Strengths of Animal Models • 1. Ethical alternative to • 3. Animals share the using humans same structures (cells, tissues, organs, • 2. Animals provide a and systems) as whole, integrated humans and function complex biological in much the same way system

Strengths of Animal Models • 4. Scientists can design experiments where they can control for more variables than with humans

Limitations of Animal Models • 1. Animals are NOT humans so results must be extrapolated • 2. Research animals are expensive to purchase, house, feed and provide with veterinary care • 3. Use of animals are governed by federal regulations

Human Studies • Most often used in developing prescription drugs • Looking for the answers to the questions below: • A. Is the drug biologically active in humans? • B. Is the drug safe in humans?

Human Studies – Three Major Phases of Clinical Trials • Phase I • 1. Determine drug’s interaction with the human system • 2. Involves a small number of healthy volunteers • 3. Takes one year

Human Studies – Three Major Phases of Clinical Trials • Phase II • 1. Controlled tests that help determine a drug’s effectiveness on certain organs, etc. • 2. 100 -300 volunteer patients • 3. Simultaneous animal and human tests to assess safety • 4. Takes 4 years

Human Studies – Three Major Phases of Clinical Trials • Phase III • Done to confirm results of earlier tests and identify any adverse reactions • 2. Clinical testing extensive – Need 1000 – 3000 volunteer patients • 3. Takes 3 years

After Clinical Trails • Firm files New Drug Application (NDA) with FDA • Takes 2 ½ years to complete • In all – 12 years from initiation of studies to FDA approval • Each new medicine approved costs millions of dollars

Human Clinical Trials Strengths • Have actual human data (how it affect human) Limitations • 1. Ethical and moral considerations of using human volunteers as test subjects • 2. Numerous variables, which may affect test data, are introduced when humans are used

To Be Continued ….