Biomedical Engineering Reference
In-Depth Information
TABL E 9.4. Rationale of Solution Formulation Selection
Factors
Selection Rationale
The same optimal and robust pH
range, with identical choice of
buffer type and concentration, is
selected to match the final drug
product
Critical excipient such as surfactant
stabilizer may need to be included
in the API matrix to minimize
physical instability issues
The recommendation for appropriate
storage temperature condition is
based on preformulation
characterization, forced
degradation, formulation DOE
optimization, and stability study
results to meet the product shelf life
requirement
The recommendation of proper
measure for headspace and light
effect is based on forced
degradation and preformulation
characterization results
Other excipients, such as antioxidant
and chelating agent, may need to be
included depending on formulation
stability properties
The acceptable pH range is selected
to balance the chemical stability,
physical stability, thermal stability,
and solubility properties. The
optimal and robust pH range can be
determined by DOE results
summarized in the context of
formulation design space
Appropriate buffer type and
concentration is selected to have
adequate buffer capacity and
minimal effect on solubility and
stability properties within the
optimal and robust pH range
