ABSTRACT
It is axiomatic that the physicochemical properties of candidate drugs can influence their subsequent development. The results of characterization studies carried out will influence their product design. However, in the interest of only doing necessary work, any detailed studies should only be carried out after the candidate drug has successfully overcome the safety and clinical trials performed in early development as many will fail at this stage. Since pharmaceuticals are formulated in a variety of dosage forms, the studies that should be undertaken include those of solid and solution state. In terms of solid-state evaluation, material science has assumed great importance (Cui, 2007), and this is especially true for compounds to be delivered via the inhalation route (Chow et al., 2007; Young et al., 2007). If the solid-state characteristics of the candidate drugs are less than desirable from a formulation perspective, then crystal engineering techniques can sometimes be employed to give them more amenable properties (Chow et al., 2008).
