Title: Pharmacovigilance
1Pharmacovigilance
- Dr. Sunettra Chinnapha
- MRCGP (UK), Diploma Dermatology (London)
- Medical Director, GSK Thailand
Vaccinology Course, Miracle Grand, Bangkok, 19th
May 2009
2Topics
- Definitions and key stakeholders
- History of major events in PV
- Methods used in PV
- Clinical trials
- Spontaneous reports
- Pharmaco-epidemiology
- Intensive monitoring
- Database studies
- PV in vaccines
- Recent developments
- Future perspectives
- References
3WHO definition
- The science and activities related to the
- detection
- assessment
- understanding
- prevention
- of adverse effects or any other drug-related
problem.
4Adverse Event
- Any untoward medical occurrence in a patient or
clinical investigation subject, temporally
associated with the use of a medicinal product,
whether or not considered related to the
medicinal product.
5Serious Adverse Event
- Fatal
- Life-Threatening
- Disabling or incapacitating
- Hospitalization (new or prolonged)
- Congenital anomaly
- Other medically important events (e.g. lab
abnormalities, etc.)
6Key stakeholders in PV
- Patients
- Health professionals
- Governments (regulatory authorities)
- Pharmaceutical companies
- International Organisations, e.g.
- CIOMS
- ICH
Pharmacovigilance Partnership for Patient Safety
7CIOMS
- Council for International Organisations of
Medical Sciences - International, non-governmental, non-profit
organisation - Established in 1949 by WHO and UNESCO (United
Nations Educational, Scientific Cultural
Organisation) - Independent forum to consider and prepare advice
on contentious issues in bioethics and safety of
pharmaceuticals for WHO, regulators,
pharmaceutical industry and others - website www.cioms.ch
8CIOMS Pharmacovigilance Working Groups
- First working group established in 1986
- Composition
- Regulators
- Company pharmacovigilance specialists
- Other invited attendees and observers e.g. WHO
co-ordinating centre - CIOMS has no legal jurisdiction and is reliant on
other bodies for regulatory or legislative
framework
9CIOMS Initiatives
- CIOMS I International Reporting of Adverse
Drug Reactions (1990) - CIOMS I Reporting Form
- CIOMS II International Reporting of Periodic Drug
Safety Update Summaries (1992) - CIOMS III Guidelines for Preparing Core Clinical
Safety Information on Drugs (1999) - CIOMS IV Benefit/Risk Balance for Marketed
Drugs Evaluating Safety Signals (1998) - CIOMS V Current Challenges in Pharmacovigilance
Pragmatic Approaches (2001) - CIOMS VI Management of Safety Information from
Clinical Trials (2005) - CIOMS VII Development Safety Update Report (2006)
10Other CIOMS Initiatives
- Current
- CIOMS VIII Signal Detection (report to be
published in 2009) - Completed
- Definitions and Basic Requirements for the Use of
Terms for Reporting Adverse Drug Reactions (1999) - Pharmacogenetics Towards Improving Treatment
with Medicines (2005) - Standardised MedDRA Queries (2004)
- Joint CIOMS-WHO Working Group on Drug Development
Research and Pharmacovigilance in Resource-Poor
Countries (2006) - CIOMS/WHO Working Group on Vacccine
Pharmacovigilance (2007)
11History of major events in PV (1)
- 1961 Thalidomide
- phocomelia in children of mothers who took this
drug during early pregnancy - ? Introduction of PV related regulations
- 1969 Clioquinol
- subacute myelo-opticus neuropathy (SMON) in
Japan - ? Discovery of ethnic and genetic influences on
drug-related risks
12History of major events in PV (2)
- 1975 Practolol
- oculomucocutaneous reaction
- ? Invention of the Prescription Event
Monitoring (PEM) in the UK and NZ - 1982 Benoxaprofen
- Liver necrosis in the elderly and unusual
photosensitivity - ? Creation of CIOMS (Council of International
Organizations of Medical Sciences)
13History of major events in PV (3)
- 1990s 3rd generation oral contraceptives
- more frequent venous thromboembolism compared
with 2nd generation OCs - ? worldwide fostering of pharmaco-epidemiology
- 2001 Cerivastatin
- more frequent rhabdomyolysis than other statins
if combined with gemfibrozil - ? Introduction of pharmacovigilance plans
14History of major events in PV (4)
- 2002 Hormone replacement therapy (HRT)
- breast cancer
- ? Scientific prestige of RCTs over pharmaco-epi
studies and re- thinking of relevant endpoints in
long-term therapies - 2004 Rofecoxib
- more frequent myocardial infarction than
classical NSAIDs - ? New concepts for risk/benefit balancing
15Methods Used in PV
- Clinical trials
- Spontaneous reporting
- (Including published case reports or literature
reports) - Pharmaco-epidemiology studies
- Intensive monitoring
- Database studies
16Clinical Trials
- Main method to gather information on a drug in
pre-marketing phase - Regulated by internationally accepted standard,
i.e. ICH-GCP - Safety and tolerability, usually 2º endpoint
- Subject to be informed of risks benefits before
giving consent - Investigators to report SAEs to sponsors within
24 hrs - Sponsors obligations
- Expedite important safety information to
investigators, ethics committees and regulatory
authorities - Annual Safety Report (EU)
17Important definitions
- SAE Serious Adverse event
- Fatal, life-threatening, hospitalisation,
disability/incapacitating, congenital anomaly and
other medically important event - not the same as clinically severe
- Adverse events
- Any untoward event
- Expected and unexpected adverse reactions
- Reactions not included or more severe or more
frequent than those listed in the product
information - SUSAR serious, unexpected, suspected adverse
reaction - Expedited reporting required IND Safety Reports
(US FDA)
18Clinical Trials Advantages
- Double-blind randomised controlled trials are
considered the most rigorous approach to
determine whether cause-effect relationship
exists between a treatment and an outcome.
19Clinical Trials Limitations
- Duration of trial too short to detect ADRs with a
long latency - Study population do not always correspond to the
general population - Strict inclusion and exclusion criteria
- Elderly, women of child-bearing age, children,
ethnic minority groups, are often excluded - Relatively small number of subjects compared to
the whole population - Very rare adverse events typically will not be
discovered in pre-licensure testing - Cannot measure efficacy against rare diseases
20Spontaneous Reporting
- Primary method of collecting post-marketing
information on the safety of drugs - Enable physicians, pharmacists and patients to
report suspected ADRs to a pharmacovigilance
centre - Also used by pharmaceutical companies to collect
information about their drugs
21Minimum Information of a Single Case ADR Report
- An identifiable reporter
- An identifiable patient
- At least one identifiable drug
- At least one identifiable suspected ADR
- Reporters contact details
22Spontaneous Reporting Advantages
- Early detection of signals of new, rare and
serious ADRs - A means to monitor all drugs on the market
throughout their entire life cycle
23Spontaneous Reporting Limitations
- Under-reporting
- Can lead to a false conclusion that a real risk
is absent - Selected reporting
- May give a false impression of a risk that does
not exist - Not possible to establish cause-effect
relationships or accurate incidence rates - However spontaneous reporting strength is still a
valuable tool in detecting new safety issues
24(No Transcript)
25Pharmaco-epidemiology
- Non-interventional study of the use and the
effects of drugs in large numbers of people - Methodologically, it was defined as
- the science of what happens anyway
- (as opposed to experimental clinical
pharmacology) - the science of the denominator
- (i.e. how to relate events occurring to single
persons to the underlying exposed population) - the science of exposure and outcome
- (i.e. relating exposure to outcome and vice
versa)
26Advantages Disadvantages of Pharmaco-epidemiolog
ical Studies
- Compared to spontaneous reports
- ? Provide both numerator and denominator for the
calculation of ADR frequencies - Do not detect extremely rare ADRs and do not
describe the quality of ADRs in detail - Compared to clinical trials (RCTs)
- ? Permit investigation of ADRs with much lower
frequency or latency - ? Real life conditions
- Prone to systematic errors (biases)
- Cannot provide answers to questions related to
very specific interventions not common in medical
practice
27Intensive Monitoring (1)
- Started in late 1970s early 1980s
- NZ Intensive Medicine Event Monitoring
- UK Prescription Event Monitoring (PEM)
- Use prescription data to identify users of
certain drug - The prescriber of the drug is asked about any AE
occurring during the use of the drug
28Intensive Monitoring (2)
- Opportunities
- Potential for the conduct of cohort and
case-control studies - Allowing the determination of absolute and
relative ADR incidences below 1 1000 - Limitations
- Number and quality of answers depend on doctors
compliance - Only feasible in countries with a centralised
system for collection and re-imbursement of
prescriptions
29Database Studies
- Data collected in a reliable and routine fashion
are needed for pharmaco-epidemiological studies - Large automated multipurpose population-based
databases - Administrative data for re-imbursement e.g.
- Kaiser Permanente (US) 7.5 M patients
- Saskatchewan (Canada) 1 M citizens
- Representative doctors e.g.
- General Practitioners Research Database (GPRD in
UK) 500 GPs, 4 M patients - Regional pharmacies and hospitals e.g.
- PHARMO in Netherlands 2 M patients
30Advantages Disadvantages of Database Studies
- Advantages over field studies
- Quick and cost effective
- No bias due to interviewer or recall
- Disadvantages
- Missing data necessary to answer special
questions - ( the reason these databases were not
designed for specific questions)
31Pharmacovigilance of Vaccines
32Smallpox vaccine Jenner started it all
33Vaccines
- Biological preparation that establishes or
improves immunity to a particular disease - Contains a small amount of a weakened agent
(virus or microorganism) - Stimulates the immune system to recognize the
agent as foreign, destroys it, and "remember" it,
so that the immune system can more easily
recognize and destroy any of these microorganisms
that it later encounters - Stored under optimal temperature to ensure
potency - Prophylactic (vaccines against infection)/Therapeu
tic (cancer vaccine)
34Smallpox
NOTE Before vaccination annual mortality was
10-15 of the worlds population
35Vaccine Preventable Diseases from the
maximum/year to 2000, USA
Source CDC unpublished data. Personal
communication J Ward (UCLA)
36The Paradox of Concern
Infection
SAE due to vaccines
37The Paradox of Concern
Infection
SAE due to vaccines
38Real or Perceived Safety Issues of Vaccines
Hexavalent Vaccines Sudden Infant Death
MMR Autism
Hepatitis B MS
Rotavirus Vaccine Intussusception
Varilrix Sepsis
Adjuvants Autoimmune Disease
39WHO on Vaccines
- There is no such thing as a "perfect" vaccine
which protects everyone who receives it AND is
entirely safe for everyone. - Effective vaccines (i.e. vaccines inducing
protective immunity) may produce some undesirable
side effects which are mostly mild and clear up
quickly. - The majority of events thought to be related to
the administration of a vaccine are actually not
due to the vaccine itself - many are simply
coincidental events, others (particularly in
developing countries) are due to human, or
programme, error. - It is not possible to predict every individual
who might have a mild or serious reaction to a
vaccine, although there are a few
contraindications to some vaccines. By following
contraindications the risk of serious adverse
effects can be minimized.
40Classification of Adverse events following
Immunization
- Vaccine reaction event caused or precipitated by
the vaccine when given correctly, caused by the
inherent properties of the vaccine - Programme error event caused by an error in
vaccine preparation, handling, or administration - Coincidental event that happens after
immunization but not caused by the vaccine - a
chance or temporal association but not causal
association - Injection reaction event from anxiety about, or
pain from, the injection itself rather than the
vaccine - Unknown events cause cannot be determined
http//www.who.int/immunization_safety/publication
s/aefi/en/AEFI_WPRO.pdf
41Programme errors
- Non-sterile injection
- infection
- Incorrect preparation
- abscess (inadequate shaking)
- drug effect (use of drug instead of
vaccine/diluent) - Injection in wrong site
- local reaction/abscess (wrong tissue level)
- nerve damage
- Vaccine frozen
- local reaction
- lack of efficacy (breakthrough infections)
- Contraindication ignored
- avoidable severe reaction
41
42Mistaking one vial for another
TT
DTP
Insulin vial
42
43FIXING THE PROBLEM
- Treat the patient
- Communicate with patient, parent, health worker
and community - Take corrective action
- Programme error
- change in logistics for supplying, storing or
handling vaccine - change in procedures at the health facility
- training of health workers
- intensified supervision
- Coincidental
- communication so people understand that link is
just coincidental - Vaccine Reaction (if higher rate than expected)
- -Withdraw specific lot (NRA action)
-
43
44Barriers to reporting among health workers
- Not considering the event as related to
immunization - Not knowing about reporting system and process
- Lethargy - procrastination, lack of interest or
time, inability to find report form - Fear that the report will lead to personal
consequences - Guilt about having caused harm and being
responsible for the event - Diffidence about reporting an event when not
confident about the diagnosis
44
45Temporal or causal AEFIs?
- The problem if a vaccine is given to every
infant in a population, every single disease in
that population will happen after that vaccine - for most people, if B happens after A, then A is
the cause of B - it explains why most diseases of unknown
aetiology have been attributed to vaccination at
one point in time until association disproven
46Temporally linked AEFIs
vaccine
AEFI
- Multiple sclerosis
- Sudden Infant Death Syndrome
- Crohns disease
- Autism
- Hep B
- DTP pert.
- Me/MMR
- Me/MMR
Adapted from S. Plotkin, Vaccine 2001
47MMR/autism trend analysis
48HepB vaccines ..
not the cause of MS!!
- incidence of MS in France 2-5 cases/100,000
population - investigated frequency in the French population
vaccinated against HepB 0.65 cases / 100,000
vaccinees
49Causally linked AEFIs
vaccine
AEFI
- anaphylaxis
- paralysis (VAPP)
- intussusception
- aseptic meningitis
- many injectables
- Polio Sabin (OPV)
- Rotashield Rh strain
- mumps/Urabe Am9
Adapted from S. Plotkin, Vaccine 2001
50GMPs, GISPs, GMPs
- good medical practices
- good immunisation services practices
- good management practices
first "do no harm principle"
51Recent development in PV
- Transparency data open to the public
- Clinical trial registry
- Spontaneous report database in CN, NL, UK
- Risk management plans
- Proactive post-marketing strategies to prevent or
minimise risk
52Future Perspectives in PV
- Post-marketing surveillance
- Data collection and evaluation
- Quality and quantity of reports
- Real life / real-time databases
- Research into risk management strategies
- effective ways to minimise risk / communicate
benefits risks of medicines - Pharmacogenetics
- Education to health professionals and patients
53References
- http//www.who-umc.org/
- http//www.cioms.ch
- Beckmann J. Basic pharmacovigilance A two-day
seminar according to a curriculum of the
International Society of Pharmacovigilance
Ha(ISoP). October 27-28, 2005, Bangkok - Harmark L and van Grootheest AC.
Pharmacovigilance methods, recent developments
and future perspectives. Eur J Clin Pharmacol
200864743-752 - Pillans PI. Clinical perspectives in drug safety
and adverse drug reaction. Expert Rev Clin
Pharmacol 20081(5)695-705
54Safety and Pharmacovigilance
Patient safety is always a priority!
55Thank you
Vaccinology Course, Miracle Grand, Bangkok, 19th
May 2009