Pharmacovigilance

Question 1

4 main aims of pharmacovigilance?

Answer 1

identify previously unrecognised drug safety hazards and seek to quantify their frequencies
elucidate those factors predisposing to toxicity
attempt to obtain evidence of safety so a new drug’s use’smay be widened
‘false +ve’ adverse drug reaction

Question 2

4 features of type A adverse drug reactions?

Answer 2

common
predictable
dose dependent
high morbidity, low mortality

Question 3

4 features of type B adverse drug reactions?

Answer 3

rare
unpredictable
independent of dose
high mortality

Question 4

describe the log interval scale related to the frequency of verbal reporting of adverse events

Answer 4

very common: >1 in 10
common: between 1 in 10 and 1 in 100
uncommon/less commonly: between 1 in 100 and 1 in 1000
rare: between 1 in 1000 and 1 in 10,000
very rare: <1 in 10,000

Question 5

limitations of pre-marketing clinical studies in identifying drug safety issues?

Answer 5

relatively small no patients treated
frequent exclusion of patients who may be at greater risk of ADR development
structured nature: limited tment duration, restricted doses, expereinced, specialist investigators

Question 6

how are ADRs detected?

Answer 6

spontaneous reporting-MHRA- medicines and healthcare products regulatory industry/yellow card= regulatory authority, journals and pharmaceutical company
case control studies
cohort studies

Question 7

what to report via yellow card scheme?

Answer 7

black triangle drugs- new products, changed indication, changed formulation, combination product
all reactions to vaccines
all paediatric reactions
serious or unusual reactions to established products

Question 8

advantages of spontaneous reporting?

Answer 8

operates as soon as drug is marketed
covers entire population receiving drug
overlooks all drugs
detects common and rare reactions
continues indefinitely
all doctors
inexpensive

Question 9

limitations of spontaneous reporting?

Answer 9

gross under-reporting of possible ADRs
no control group
poor quality data
delays in reporting
misleading reports
difficulty recognising previously unknown ADRs
denominator data poor

Question 10

how can cohort studies be used to report ADRs?

Answer 10

select group of people exposed to drug and follow up to see who gets ADRs- rate and outcomes
control group
prospective or retrospective, hypothesis testing and generating
prospective part expensive, and lose subjects to follow up

Question 11

how can case control studies be used to report ADRs?

Answer 11

select people with ADR= cases, and match controls= without adverse event
compare exposure to risk factor i.e. drug, so who took the drug?
calculate OR= A X D/ B X C

Question 12

advantages of case-control studies for reporting ADRs?

Answer 12

cheap
can give quick answer if suitable database available
good for rare ADRs or where long latency
indicate degree of increased risk

Question 13

disadvantages of case-control studies for reporting ADRs?

Answer 13

many biases
expertise 
credibility
suitable database often not available
requires a prior hypothesis

Question 14

why are ADRs undereported?

Answer 14

FAILURE
failure of ptnt to report ADR to dr
ADR is too trivial
ignorance of reporting and its procedures
lack of time
uncertainty of relationship between drug and ADR
relating to duration of marketed drug
experience and familiarity with the ADR