Form Considerations in Preformulation

Preformulation studies inevitably extend beyond the basic characterization of the lead compound, because what is considered as an acceptable characteristic of a lead compotmd will largely depend on the intended or anticipated dosage form. For example, the solubility issues will largely determine the route of administration conversely, if a particular route of administration is the only desired route, then preformulation studies should attempt to find out the structural changes necessary for the candidate molecule. 

In most instances the choice of a prospective dosage form will depend on a variety of factors  

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With these limitations in mind, this chapter concentrates on the specific considerations which are fundamental to the development of pharmaceutical dosage forms designed for application to the skin. Many of the early pharmaceutical development stages for these dosage forms, such as preformulation and drug substance stability, are common to dosage forms designed for other routes of delivery. These have been fully discussed elsewhere in this volume and will not be discussed in depth here. 

The contents and definition of preformulation studies included are generally broader than those found in published articles or conventional textbooks. The intent is to include articles to assist the formulator in developing an optimal and ideal dosage form either for marketing or for subsequent reformulation. Thus, the following considerations should be included in a comprehensive preformulation report. 

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