Lecture 3 Flashcards
Definition of Clinical trials from NIH
A research study in which one or more human subjects are prospectively assigned to one or more interventions (which may include placebo or other control) to evaluate the effects of these interventions on health-related biomedical or behavioural outcomes.
What are the 5 stages of clinical testing?
- Pre-clinical tests
- Phase I
- Phase II
- Phase III
- Phase IV
What happens in the pre-clinical tests? (2)
Testing in animals and on cells
establish:
- dose
-major effects on organs
-long term side effects
What is Phase I of clinical trials?
First in man trials/first human dose
How many people is the drug tested on in Phase I and who are these people ?
Conducted with smaller samples (20-100) of usually ‘healthy volunteers’
What happens in Phase I?(6)
- Establish dosage, frequency
- takes up to 2 years payment
- thought little risk
- biotech medicines may behave differently
- conducted on smaller samples (20-100) of usually healthy volunteers
Phase I of clinical trials can be harmful. Give 2 examples of phase I tests that went wrong
- Autoimmune drug trial 2006
- Chronic pain drug trial 2016
What went wrong in autoimmune drug trial 2006?
- 6 participants needed up with organ failure, life-threatening conditions
What did the autoimmune drug trial 2006 lead to ?
Led to changes in trial management - importance of sequential dosage
What went wrong in chronic drug trial 2016? (2)
- One participant died, others left with severe brain damage
- Issues with jumps in dosage during trial
What is Phase II of clinical trials?
Proof of concept
Who does Phase II of clinical trials test on ?
- Test on patients with the disease (200-500)
What does phase II of clinical trials look at?
Looks at:
- doses
- response rates
- side effects
How long does phase II of clinical trials take?
Takes about 2 years
Where do phase II tests take place and by who monitors the participants being tested ?
Usually in hospital with non-pharma doctors
Who wants pays the participants?
- hospitals/clinical research networks paid to recruit (cover costs)
The drug is usually patented at what stage ?
Phase II
What is phase III of a clinical trial?
Efficacy of treatment
How many people are involved in phase III ?
May be thousands involved
What happens in phase III ?
- Randomised controlled trial of new drug versus current treatment (if exists) - can be tested against placebo
- Collect data on response, side effects and death
- First real evidence of safety and efficacy
What is phase IV of a clinical trial ?
Post license testing
What happens during phase IV ?
- Monitor safety and efficacy
- Yellow card system UK
- Patent runs out out after 5 years - attempt to extend with ‘over the counter’ e.g. ibuprofen
- Big push to gets drugs into practise in first few months
- Long term side effects take years
There can be exceptions to clinical trials. Name one example
University of Oxford Covid-19 vaccine development
When and what happened at each stage of the university of Oxford Covid-19 vaccine development?
- Phase I - April 2020 - healthy volunteers, n=1,077
- Phase II/III - May 2020 - healthy adults and children, n=47,000 in 4 countries (UK, USA, South Africa, Brazil)
- Nov 2020 phase II/III trial results published in The Lancet
- Approved for use December 2020
