NF IVIV Flashcards
Standardised conditions 3
Temperature
Solid-liquid interface
Media composition
Biopharmacuetical def of dissolution
amount of active ingredient (in solid dosage form) the is dissolved per unit time (under standardised conditions)…
Two main purposes of dissolution testing
QC and predict PK in vivo
Dissolution QC purposes 4
Batch reproducibility
Shelf life stability
Batch release
Assures changes to manufacturing process do not impact performance (requires BE study)
Predict PK in vivo purposes
Guide formulation selection, design and scale-up during
development
– set specifications for API form and particle size
– Guide bioequivalence strategy
– Biowaiver
– In vitro-in vivo correlations
The main factors influencing dissolution
Testing Conditions
Drug Formulation
Drug properties
Condition factors influencing dissolution 3
Apparatus
Method parameters
Dissolution medium
Formulation actors influencing dissolution 3
Compositon
Manufacturing process
M/r?
Drug properties influencing dissolution5
Solubility in dissolution medium Hydrophilic/hydrophobic Shape/size Crystalline/amorphous Polymorphs present?
Phycoco,logical conditions affecting dissolution
Properties of GI fluids (composition, pH)
� Gastric emptying (especially for non
disintegrating systems)
� Intestinal transit time
� GI motility and hydrodynamic patterns
� GI enzymes
� Fasted state/ Fed
The media considerations
Buffers
Media proposed by pharmacopeia
Bio relevent media
Hydrodynic conisidrations 5
Design if apparatus Agitation intensity Flow volume Viscosity if medium Formulation/drug location
pH of fasted/fed small intestine
Fasted 6.8
Fed 5
Bio relevant media types
Milk (fed stomach)
Fasted/fed state simulated gastric/intestinal/colonic fluid
Two closed testing apparatus
USP apparatus I (rotating basket)
USP apparatus II (rotating paddle)
Advantages of closed system ap 3
Simple
Robust
Adequately standardised
(Per infant incubation of dosage form in the SAME medium)
Disadvantages of closed app 3
Homogenising
Dispersion
agglomeration
Open system appparatus
USP AP III (cylinder bio-dis)
USP AP IV (flow through cell)
Advantages of open systems 3
Multiple pH levels/sequential changes
Residence time in GI
Hydrodynamics in GI
Ap IV can be used for
Specific dosage forms
Multi particulate or suspensions
FDA definition of IVIVC
Mathematic model describing the relationship between in vitro property and relevant in vivo response
Generally:
In vitro: rate/extent of dissolution/release
In vivo: plasma drug conc/amount absorbed
BA
Rate and extend to which an active drug is absorbed from the drug product and becomes available at the site of caution
BE
Absence if significant difference in BA in pharmaceutical alternatives
(Administered at same molar dose + similar conditions)
Which level can be used to justify changes
Level a