clinical trial design week 9 Flashcards
1
Q
what are the stages in development of a new drug
A
- research (can take up to 10 years), within this time have to do toxicity studies, register intellectual property, decide what formulation they want
- then decision for development can take up to a year once they have evidence from their research
- then go into the development stages, 1,2,3, (phase 4 is post marketing)
2
Q
what tests do they do pre-clinical development of a new drug
A
- animal pharmacology (dose, adverse effects)
- animal toxicology (teratogenicity, fertility, mutagenicity)
- tissue culture
3
Q
what happens in phase 1 of clinical development
A
volunteer studies
- clinical pharmacology in normal volunteers generating pharmacokinetic, metabolic and pharmacodynamic data
- usually involves around 100 subjects (normally healthy individuals)
- certain drugs e.g. cytotoxic will bypass this phase (if developing drugs for cancer won’t give them to normal volunteers so bypass this stage)
4
Q
what happens in phase 2 of development
A
- clinical investigation to confirm kinetics and dynamics in patients (who may have renal/liver/GI absorption problems)
- provides some evidence of efficacy and identifies a likely dosage range
- involves up to 500 patients
5
Q
what happens in phase 3 of development
A
- formal therapeutic trials where efficacy will be established and evidence of safety obtained
- involves 1,000-10,000 patients
- at completion all data (pre-clinical, pharmaceutical and clinical data) is submitted as an application to the regulatory authority for a license to sell the drug
6
Q
what is phase 4 of development
A
- post-marketing surveillance to produce evidence of long term safety
- may involve tens or hundreds of thousands of patients world wide
7
Q
who are clinical trials regulated by
A
- MHRA
- test efficacy (compare with placebo, compare with another drug)
- test safety
8
Q
what is an observational study
A
- if you don’t want to do a big study you can do a small one say 500 patients in Aberdeen
- although there are issues with replication and diversity, patients in Aberdeen may be very different to those in Japan
- can be issues with causation or correlation because it is a small study
- observational studies on their own are not robust enough to allow companies to give out drugs
9
Q
what are pilot studies
A
- not to estimate outcome, they are to test study design
10
Q
what is a double blind trial
A
- neither patient or doctor knows which compound the patient is getting
11
Q
what is a single blind study
A
- patient blinded, doctor knows
12
Q
what is a prospective study
A
- protocol is decided before hand
13
Q
what is a retrospective study
A
- looking back at data, so more open for bias, can put your own spin on data
14
Q
what are the different comparisons you can do to test efficacy in clinical trials
A
- compare with placebo
- compare with other drug
15
Q
what is cross over design
A
- both groups get the two different compounds at some point with wash over period in between
- e.g. group 1 gets drug A, wash over period for 8 weeks, then group 1 gets drug B and vice versa for group 2
- allows you to use a smaller number of people
- can be useful if you can’t find enough people for two separate groups
- one of the issues is patient can change over time e.g. change their diets
