Drug Testing

							               Objectives
• outline the process of testing new drugs
  for safety and effectiveness
             Drug Testing
Drugs must be tested

• To check that they work
• To check that they are not toxic
• To test for side effects

It takes years to develop a new drug
• Tests on animals are   • Tests on humans are
  called laboratory        called clinical trials
  tests.
• Drugs tested in the lab on cells are called

• In vitro tests

• Trials using animals or humans are called

• In vivo tests
1. Search through natural
sources to find a
chemical. Look at
computer models. Do In
vitro tests on human cells


 2. Animal tests




3. Clinical trials
Drug Testing. Put the following in the correct order.


f. Tests on human volunteers.               e. Computer modelling.


  a. Tests on animals.          d. Tests on a few people with the illness.


 c. Find a suitable chemical. Look at earlier treatments. Look in plants.


            b. Tests on human tissue samples..
 The correct order is ………
c. Find a suitable chemical. Look at earlier treatments. Look in plants.


 e. Computer modelling.


b. Tests on human tissue samples.


  a. Tests on animals.


  f. Tests on human volunteers.


  d. Tests on a few people with the illness.


                 WHY IS EACH STAGE NECESSARY?
 WHY EACH STAGE IS NECESSARY
c. Find a suitable chemical..


 e. Computer modelling. Checks that the molecules are the correct shape.


b. Tests on human tissue samples. Checks that the new drug is not toxic.


  a. Tests on animals. Check for side effects. Does the drug work in a
  whole animal

  f. Tests on a few human volunteers. Check for side effects.


  d. Tests on a few people with the illness. Does the drug work?
                 Patents
• If animal tests go well, then the developers
  will apply for a patent
• This means no other company can sell the
  drug for 20 years
• However, because clinical trials take so
  long, the company only gets around 10
  years when they are the only ones selling
  the drug
                    Task
• Use your text books to complete the table
 STAGE         TESTING                  TO FIND OUT




 ONE           Drug tested on human     1. How safe the drug
               cells grown in the lab       is for human cells
               (In vitro tests)         2. How well it works
                                            against the disease
 TWO


 THREE
              Clinical trials
• People who take part will be put randomly
  into one of two groups. Random groups
  are important so the results are reliable
• One group will be given the new drug,
  another group will not. This is the control
  group
• Results from both groups are compared
               Clinical Trials
• Double blind trial:
• The patient and the doctor do not know if they
  were getting the new drug or not
• Blind trial:
• The doctor knows but the patient doesn’t. This
  may be so the doctor can look for a certain side
  effect
• Open trial:
• Both the patient and the doctor know
• A random double blind trial is the best type
                  Placebo
• In most clinical trials the control group are
  given the treatment currently used
• If there isn’t any current treatment a
  placebo is used. It looks like the real
  treatment but has no drug in it
• Using a placebo in clinical trials is very
  rare
              Ethical issues
• It may seem unfair that the control group
  miss out if they take a placebo but proper
  testing is needed
• If the trial shows the risks are too great it
  will be stopped
• If the trial shows the drug has benefits it
  will immediately be offered to the control
  group
           No control group
• Occasionally a new drug is given to all the
  patients
• This is where there is no current treatment
  and the patients are so ill they will not
  recover by themselves
• It would be wrong not to offer the hope of
  a new drug to all those patients
               Questions
• Explain why drug trials must be random

• Explain the differences between blind and
  double blind trials

• Describe a situation in which it would be
  wrong to use placebos in a trial
• Drug testing in the United Kingdom is
  thorough and effective.
• However, occasionally things go wrong.
• Do you know anything about a drug called
  thalidomide?
• Do you know anything about the TGN1412
  drug trials of 2006?