Clinical Measurement of Drug Action Flashcards
What is a biomarker?
Something measurable that tells you about a disease state. A readily measurable marker of response.
What is a surrogate endpoint?
Biomarker used for Regulatory Approval. It has a strong association with potential clinical outcome.
e.g. reduction in viral load, CD4+ cell count…
What is the difference between a biomarker and a surrogate endpoint?
A biomarker reflects an important feature of a disease (reflects a response to drug). They are essential in clinical pharmacology.
A surrogate endpoint are SUPPOSED to be readily measurable biomarkers that closely reflect clinical outcome. They are optional but commercially important.
What are important features of biomarkers?
- repeated measurements possible
- cheap
- high content info
- rapid indication of response
- prognostic or diagnostic value
What are 3 things to consider when looking at clinical outcomes? (e.g. death, pain)
- can be subjective (pain)
- Often happens only once
- can take many years for differences to be evident
Out of biomarkers and clinical outcomes, which has lower content information?
Clinical outcomes.
What are 2 issues with biomarkers?
- BP lowering is predictable
- BP rarely predicts individual beneficial clinical outcome
Is BP a good surrogate end point?
NO.
- BP data would predict equal effectiveness of treatments
- Disease processes are complex and sometimes you need more than one biomarker.
What are benefits of using surrogate endpoints than outcomes?
- high content info
- low costs
- accepted as strongly correlated with outcome
- cheaper and shorter than clinical trials
What is the most widely used surrogate endpoint?
Drug concentration. No clinical outcome is required.
Adverse event assessment and monitoring occurs in which two phases?
Phase 3 and 4
What are the biomarkers/surrogate endpoints for the liver, kidney and heart?
Liver: ALT (alanine aminotransferase)
Kidney: Serum creatinine
Heart: QT interval
