ABSTRACT
INTRODUCTION Lead drug substances might be derived from three sources: chemical, biological, and botanical (including minerals). These compounds (or a mixture of compounds) may be delivered to the preformulation team at a myriad of characterization stages. Whereas the drug discovery group has, by this time, established the pharmacological activity, the synthesis or extraction group has, by this time, not necessarily fully characterized the lead compound. There is also a proposal on the table regarding the prospective drug delivery systems and their routes of administration. The task of the preformulation group therefore starts with the development of a detailed plan for the complete characterization of the lead compound. The depth and breadth of the characterization would depend on the type and source of the compound as well as its destination-the dosage form. Whereas the formulation part is yet to come, the preformulation group must provide lead suggestions on the choice of the excipients through preliminary interaction trials. These studies must be conducted using analytical methods that are established though not necessarily fully validated at this stage.
