Pharmacoeconomics Flashcards
Pharmacoeconomics
Comparing the costs and benefits of interventions and making choices is the basis of health economics. Decision makers need to consider the cost and the benefit of new interventions; in the UK, the cost-effectiveness is preferred. Interventions are compared with one another or the SOC, and an incremental cost for the benefit is reported.
EQ-5D
EQ-5D questionnaire includes mobility, self-care, effect (improvement, worsening) on activities, pain/ discomfort experienced, anxiety/ depression. The EQ-5D does not include social contact or employment, and certain diseases influence EQ5D more (physical conditions may influence the score more than mental conditions).
The EQ-5D can be used to calculate utility and compare between therapies; a quality-adjusted life year (QALY) is often used – one QALY is equal to 1 year of life in perfect health.
A drug is deemed cost-effective
if it is £20-30,000 ICER per QALY; end of life treatment (extends life beyond three months) is cost effective if £50,000 ICER per QALY.
If a drug falls in quadrant 1
it is less effective and more expensive, so will be rejected. If a drug falls in quadrant 4, it is more effective and less expensive, so will be accepted. If a drug falls into quadrants 1 or 3, an ICER must be performed to compare the cost-effectiveness.
Decision analysis models are used to simulate costs & consequences of different care pathways
The probability of a patient following a pathway is assessed and the pathway costs and benefits assigned; decision trees may be used for simple diseases in acute settings, but for complex diseases, there are too many options for them to be viable.
The Markov Model
The probability of length of time spent in different health states is calculated, developing QALY based on the cycling. This gives a better indication on cost-effective scale. It is useful for cancer, as it accounts for progression states.
Sensitivity analysis
SA is essentially the study of how changes in model inputs (quantities, prices, life years, probabilities) affect model outputs (average or expected costs, average or expected benefits, average or expected ICER or Net Monetary Benefit).
There are two types of sensitivity analyses:
- Deterministic: Values for one or more parameters are chosen, and the rest are kept constant
- Probabilistic: Parameters and probability distribution are assigned, and simulations are used to compute new ICERs
Evaluating the cost of anti-cancer drugs
To gain marketing authorisation, there is a high cost for pharmaceutical companies, so they aim to make some of this back. Most incurable cancers are treated with each approved agent (sequentially or in combination), creating a virtual monopoly because the use of one drug does not automatically mean that the others are no longer needed. Generics are seen as sub-standard to new therapies and are therefore not used. In addition, cancer is seen as a more serious disease, so there is increased willingness to pay a higher price.
Cancer drugs fund
Established in 2010, the aim was to give cancer patents access to non-NICE approved drugs. Initially set at £50 million, the fund is now £280 million. It was put into place temporarily as a new method of cost effectiveness analysis was developed – value-based pricing (VBP). In terms of pharmacoeconomics, the cancer drugs fund is disastrous; there has been an exponential rise in cost.
The CDF may undermine the underlying NICE/NHS principle that all lives are of equal value. The new CDF (from 2016) is part of NICE and aims to review all new cancer drugs within 90 days of license for use in England, and 1 of the following 3 decisions will be made regarding the use:
- Yes - the drug should be routinely available on the NHS
- No - the drug should not be routinely available on the NHS
- Maybe - the drug can be made available via the Cancer Drugs Fund, to ensure efficacy before allowing routine availability
