Drug Development Process 1

Question 1

Define a drug

Answer 1

A chemical compound of defined structure that upon administration to a living organism produces a biological effect.

Question 2

What can a chemical compound be?

Answer 2

• A natural product which is isolated and purified
• Synthetic i.e. made by a chemical process
• Semi - synthetic

Question 3

What is a medicine?

Answer 3

A chemical preparation which contains a drug and other substances.

Question 4

What can be prescribed for waterborne parasites?

Answer 4

Pomegranate as it contains a powerful antihelminthic.

Question 5

When did the Royal Pharmaceutical Society form and what did they do?

Answer 5

In 1841
They began legislating for higher standards

Question 6

What did the Venereal diseases act of 1917 lead to?

Answer 6

The control of unsubstantiated claims for medicines
- Thought as one of the forbears of evidence based medicine

Question 7

What happened in 1956 for the development of legal framework?

Answer 7

Previous legislation was rationalised and the control of both the sale and manufacture of medicines was combined into a single piece of legislation.

Question 8

What is extemporaneous dispensing?

Answer 8

The preparation of a medicinal product for an individual patient by the instruction from a doctor.

Question 9

State the standards for the following elements of extemporaneous dispensing.

Answer 9

• Personal hygiene
• Personal protective equipment
• Work area and equipment
• Label preparation
• Avoidance of contamination
• Suitable record keeping and processes

Question 10

Why were galenicals made?

Answer 10

• To separate active compounds from inactive from plants

Question 11

How were galenicals made?

Answer 11

• By macerating a crude drug with a solvent

Question 12

Why were pills good to make?

Answer 12

• Easy to make
• Compact
• Could mask foul tastes

Question 13

What are the problems with pills?

Answer 13

• Were often coated in insoluble materials and too dense
• This meant they often went through the GI tract unchanged and unabsorbed.

Question 14

What is aromatic water?

Answer 14

• An aqueous solution of a volatile substance

Question 15

What is aromatic water used for?

Answer 15

• Flavouring agent
• Some do have mild therapeutic actions usually carminative

Question 16

How are waters now prepared?

Answer 16

• From their concentrates; must be diluted with 39 times its volume of potable water to make a single strength water

Question 17

How do you make money on a drug?

Answer 17

• Stop other people selling it who don’t have the cost of developing it
• Market it
• Develop a patentable formulation

Question 18

What must you show to patent an entity (not just a drug)?

Answer 18

• Must be novel
• Must involve an inventive step
• Must have utility

Question 19

What is the lifespan of patents?

Answer 19

20 years

Question 20

Describe discovery of a target selection/assay development.

Answer 20

• Starts with research into disease mechanisms to identify potential targets that a drug could work on

Question 21

What is the next stage of drug discovery?

Answer 21

Finding a chemical agent that will act specifically on the target - which is called a lead

Question 22

Describe the sources of leads.

Answer 22

• Originally relied on natural sources
• Now we are able to ‘design’ leads

Question 23

State the 5 sources of leads.

Answer 23

• ‘Design’
• Plant
• Marine
• Microorganism
• Semi - synthetic

Question 24

Describe lead selection - SAR

Answer 24

• Develop an assay that displays interaction of your molecule with the
  target plate based/cell based
• This identifies ‘drug like’ chemistry that is active against the target
• Possible to start at this stage if you have a chemical you know has an effect

Question 25

Describe lead refinement.

Answer 25

* Activity/Potency (how well it works) * Selectivity (how well it binds just to your target) * Stability (will the compound fall apart in solution?) * Toxicity * Solubility

Question 26

Describe pre-clinical development.

Answer 26

* Routes of manufacture and purity * Partition co-efficient and pKa * Crystal properties- polymorphism (solid state) * Particle size * Dissolution * Biopharmaceutical properties * Chemical stability- long term * Robust analytical methodologies * Routes of administration and formulation

Question 27

Why do we use animals?

Answer 27

In the body a drug may have problems we can’t predict It may:- * be deactivated before it reaches the part of the body where it needs to act * be quickly excreted from the body * be changed in the body to a different chemical, may become inactive or toxic * Affect other parts of the body as well * have unwanted side effects

Question 28

What are the principles of 3Rs for animal testing?

Answer 28

Refinement - Development of methods to reduce distress to animals Reduction - Obtain most precise information with smallest number of animals Replacement - Use of alternatives to animals

Question 29

How do we screen the drugs in animals?

Answer 29

* Small doses of drug are given to mice (or rats) with a tumour * The tumour size is measured regularly to check for a response * The animal is under close watch to check for side effects

Question 30

Why do we animals have their own care team?

Answer 30

- To check if the drug kills the cancer cells inside the body and at what dose it does this

Question 31

What are clinical trials?

Answer 31

Human trials: Phase 1 - involve a small number of volunteers People given small doses of drug and carefully monitored Trial tests whether the new drug is safe and how the body deals with it Phase 2a/b - involves small number of patients Designed to test whether the new drug has a positive effect on the disease being treated and determine the dose Phase 3 - involves a large number of patients Trails tests efficacy and safety in a larger population Phase 4 - Post marketing safety and efficacy

Question 32

Where might drugs come from in the future?

Answer 32

- genomics - proteomics - metabolomics

Question 33

Describe genomics?

Answer 33

Study of the genome of an organism.

Question 34

Describe proteomics.

Answer 34

Study of the structure and function of proteins

Question 35

Describe metabolomics.

Answer 35

Studying the cell's activities via its metabolites