FORMULATION DEVELOPMENT
Compared to small molecules, biopharmaceutical drugs such as mAbs offer
high specificity and potency, arising from their macromolecular
structure. However, their structural complexity is the cause for
challenges in formulation and delivery of mAb drugs (Mitragotri, Burke,
& Langer, 2014). Formulability is defined as the suitability of a drug
product to be formulated in a way appropriate for the desired route of
administration (RoA) or delivery method. Its quality attributes include,
but are not limited to, solubility, stability, viscosity and
aggregation. Early formulability assessment is an important aspect in
the development program of any new biopharmaceutical and is often not
emphasized enough (Zurdo, 2013). In line with the QbD paradigm, the
intended use of an antibody is considered in the target product profile
(TPP), usually during early stages of drug development. By completing a
TPP, considerations into RoA, dosage form, bioavailability and stability
can be addressed in early stages (Figure 2). Ultimately, every single
aspect of development that affects the efficacy, cost or simplicity of
an antibody can become the difference between success and failure of a
drug (Zurdo, 2013).