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Describe phase 1 of clincial trails - size, lenght

20-100 healthy volunteers
last several months to a year


what are they testing for in phase 1

does - may gradually increase throughout
side effects
bodys reaction
process in the body


how many drugs move from phase 1 into 2

approx 70%


what is the purpose of phase 2

asses the safety, efficacy and side effects


how big is phase 2

upto several hundred patients


how long is phase 2

6 months to 3 years


describe the two steps of phase 2

phase IIa - small number of patients to demostrate saftey and first signs of efficacy

Phase IIb established does and overall efficacy, establish inital benefit to risk ratio


purpose of phase 3

efficacy and monitoring of adverese reactions


number of partcipants in phase 3

300-3000 volunteers who have the condition


how long does phase 3 last

1-3 years


describe the two stages of phase 3

phase IIIa - evidence of saftey, efficiacy and side effects, often include pivotal trails

Phase IIIb - conducted after the drug has been submitted for marketing approval
compare to current treatments
use in additonal populations


describe phase IV

commerially orinentated trails conducted after the drug has been approved for marketing
expand testing to broader patient population
look at long term effectiveness


what is an observational study

address questions that randomsied control studies cannot
lead to a determaination of associations
idenitfy patterns


describe the translational pipeline

idea - generated by oberservation
basic research - idea development
clinical trials - drug development and testing
regulatory approval
patients care


example of a randomaised control trail

effectiveness and sustainaible mutilmedia education for children with asthma
control gorup pedatric pateints given standard educational rescourse
experimental group pedriatic pateints given standard and mulitmedia rescources
reduction in daily symptoms, emergrnecy vists, school missed and days of limited activty in experimenal group


what is a single blind trail

patients dont know the treatment but doctors do


what is a double blind trail

researches and patients do not know


what are the benefits of blind trails

prevents doctors, researches and pateints from knowing which study group they are in so they cannot influnce results
protects against bias - reduces performance and ascertainment bias


what should you do if you cant blind

measure objective as possible
treat groups in the same manner
assign indivduals to differnt surgeons each performing


what is intention to treat analysis

all patients who were enrolled and randomly allocated to treatment are included in the analysis and are analysed in the group to which they were randomsied


inclusions in ITT happen even if ..

- withdawal
- protocol violations
- losses to follow up


pros of intention to treat analysis

more reliable estimate of true treatment by replicating what happens in the real world
simplifies task of dealing with suspiciuos outcomes
prevents bias when incomplete data is related to outcome
preserves sample size
when ITT analysis and per protocol analysis come to the same conclusions, confidence in the study is increased


cons of intention to treat analysis

estimate of treatment effect is conserative becuse of dilutaion to non compliance and more prone to type 2 errors (false negatives)
does not asses treatment efficacy accutately unless there is negligable protocol violations
protocol violations and poorly conducted trails may cause results obtained from two different treatment groups to appear similar


what is the role of NICE

act as a rationaing body to reduces varaiation in acess to new interventions
guideline development group, on the use of drugs and spending


what is the cost effective analysis

is looks at the ratio of cost to health effect (QALYS)
compares the price and effectivness of treatments


what are QALYS

'currency' for health
a measure of the overal effictiveness, combines
- lenght of life
- quality of life (1=full health, 0=dead)


what is the equation for QALYs

life expectancy x (HR-QoL)


what is the EQ-5D questionnaire

pateinst are asked 5 questions referring to 5 domains of health e.g mbolity, pain
this gives as overall score
asses life today


time trade off

asks how long you would like to live at full health compare to living in your current state
- the worse the health state the more time one will be willing to sacrifes in order to avoid it e.g rather than living for 10 years at 50% health you would rather live for 2 years at full health


what is the standard gamble

the worst the health state the higher the risk of possible immediate death one will accept in order to avoid current state


incremental cost effictiveness ration equation

difference in cost/difference in QALYs
e.g avg cost of B - avg cost of A/avg QALY B - Avg QALT A
= £500 per QALY gained


what is the current ICER threshold

1 QALY = £20,000