BRACKETING AND MATRIXING DESIGNS (Q1D)

· To reduce the total number of samples to be tested, the ICH guidelines introduced the concept of bracketing and matrixing. · BRACKETING · Definition : Bracketing is the design of a stability schedule such that only samples on the extremes (high level) of certain design factors (e.g., strength, container size and/or fill) are tested at all time points as in a full design. · The use of a bracketing design would not be considered appropriate if it cannot be demonstrated that, o the strengths or container sizes and/or fills selected for testing are actually the extremes o Bracketing can be applied to studies with multiple strengths where the relative amounts of drug substance and excipients change in a formulation. · ...