Drug Safety Flashcards
What is pre-clinical testing?
Where pharmaceutical companies trial drugs for toxicity in a number of tissue in vitro or in vivo
What does drug licensing require?
Requires 2 rodent species and 1 non-rodent species through intra-venous, intra-peritoneal or oral dosing
What are Phase 1 trials?
20-100 healthy volunteers are given the drug to assess the pharmacokinetics and to determine dosing regiments and safety
What are Phase 2 trials?
100-500 patients with the disease/condition given the drug
Looks at efficacy and side-effects
What are Phase 3 trials?
1000-5000 patients given the drug
Assesses long-term use and its efficacy - better than best current treatment?
How much does it cost to fully develop a drug?
≈1Bn pounds
How long does it take to develop a drug?
12-15 years
What are adverse drug reactions?
It is a response to a medicinal product which is noxious and unintended
This event has at least reasonable probability
What are type A adverse drug reactions?
Exaggeration of a drugs normal pharmacological actions when given the usual recommended dose
What’s an example of a type A adverse drug response?
Respiratory depression with codeine in CYP2D6 ultra-rapid metabolisers
What are type B adverse drug reactions?
Move, responses that are unexpected/unpredictable from the known pharmacological actions of the drug. May only be discovered after the drug has already been made available for general use
These are rare; 1:100,000 patients
Give 2 examples of type B ADRs.
Anaphylaxis with penicillin
Skin rashes with antibiotics
Typically immune mediated
What are type C ADRs?
Persist for a relatively long time after drug withdrawal
What are type D ADRs?
Become apparent some time after use. Timing may make them more difficult to detect
What are type E ADRs?
Associated with the withdrawal of the medicine
What are idiosynchratic ADRs?
Type B adverse drug reactions - off target
What was thalidomide originally - then laterally - marketed as?
A sedative/hypnotic
Later marketed to alleviate morning sickness
What did thalidomide cause?
Teratogen
Inflammation of fat cells under the skin
How long is the exclusivity license after a drug is marketed for general use?
15 years
What % of drugs have been withdrawn over safety concerns over past 20 year?
4% of all licensed drugs
What effects does ADRs have on pharmaceutical companies?
Risk of ADRs make them more cautious and hence less inventive for new ideas
Prevent potentially good drugs from getting to the market and helping patients who could benefit
What is cervastatin?
A lipid lowering drug
Why was cervastatin removed from the market?
52 deaths reported from kidney failure - rhabdomyolysis - post marketing
How many hospital admissions are because of ADR?
6-7%
