Drug Development Process Flashcards
What are the two main approahces to therapies in respiratory disease
- Symptomatic Relief
- Not disease modifying
- Disease modifying/curative
Outline the pre-clinical drug development (after target identification)
- Synthesis of compounds
- Preliminary screening for pharmoclogical activity
- More pharmacology, Preliminary toxicology
- Selection of promising compounds
- Full animal pharmacology, subacute toxicology
- Preparation of formulations for human studies
What are some outcomes of interest when developing new compounds
- Pharmacodynamics
- Effect
- Minimal Effective Dose
- Pharmacokinetics
- ADME
- Toxicology
- Adverse effects
- NOEL - concentration of drug where no effect is seen on animal
- NOAEL - Beneficial effects but no adverse effects
- Mutagenicity
-
In vitro interaction potential
- CP450
- Reproductive and fertility studies
- Carcinogenesis
- Long-term toxicity
What are some pre-requisites for studying drugs in humans
- Adequate pre-clinical data
- Safety
- Toxicology
- Appropriate drug formulation
- Clinical rationale
- Detailed study protocol
- Risk-Benefit analysis
- Ethics committee permission
- Clinical Trials Registry Number
What are the stages of a clinical trial and briefly explain what happens at each stage
- Phase I
- Healthy volunteers (Except in cancer as very toxic)
- Safety and tolerance
- Phase IIa
- Small studies in patients
- Tolerance, efficacy, PoP
- Phase IIb
- PoC and Dose-ranging study
- 3 dosease vs placebo
- Phase III
- Larger efficacy studies in patients
- Compared with established agents
- Phase IV
- Post-marketing studies to confirm safety, pharmacoeconomics and new indications
What are some outcome measures for clinical trials and breifly explain them (6)
- Proof of Mechanism
- Show effect - mediator level
- Proof of Principle
- Pharmacological effect with a change in biomarker (Phase I/IIa)
- Prood of concept
- Pharmacological or clinical effect on well-validated disease marker/symptom
- Symptomatic Efficacy
- Functional Benefit
- Disease Modification
What subjects are used in Phase I trials?
Healthy human subjects
- Usually not women as there is often no fetotoxicity data*
- Healthy subjects cannot be used for Phase I when the drug is an anti-cancer as these are cytotoxic*
What is the starting dose used for Phase I trials
1/10 of the predicted dose on man
What is the main primary outcome for Phase I studies (3)
- Safety/Tolerance
- Pharmacokinetics
- Drug and food Interactions
- PoM
What subjects are used for Phase II Studies
Patients
What are the primary outcomes for Phase II (a and b) studies (4)
- Pharmacokinetics
- Side Effects
- Toxicity
- PoP/PoC
- Efficacy vs placebo/active comparator
- Optimal Dose
- Dose-ranging
What subjects are used in Phase II trials
Patients
Some additional use of animals for chronic toxicity and reproductive studies
What study deisng do Phase II trials usually use
Double-blind randomised control
Against placebo and active comparator
What are the primary outcomes for Phase III trials
- Efficacy
- Functional
- Symptomatic
- Safety
- Long-term tolerance >1 year
- Risk:Benefit Ratio
What are some special safety considerations for drug development in asthma
- Young:
- Effects on growth
- Pregnancy
- Hyperractivity:
- Inhaler-Induced bronchospasm