At this early stage of pharmaceutical development, the key goal is successful PK and Tox studies with visibility into first in human studies. This requires a physical form of the API that has the best absorption properties to provide acceptable exposures and safety margins.  Physical and chemical stability must be evaluated to ensure no form change during the course of the Tox studies.  Also, choosing the best API form for these studies minimizes program delays associated with bridging studies.

Activities involving solid state properties include:

     •     Preclinical and toxicology formulation development

     •     Based on solubility/stability needs

     •     Solid form screening

     •     Investigate Salts/co-crystals/amorphous or is crystalline neutral acceptable?

     •     Property assessment for regulatory filing

     •     Performed with desired API phase to avoid repeating

     •     Solubility and dissolution

     •     Biorelevant media and process solvents

     •     Physical and chemical stability

     •     Crystallization

            •    What other forms to avoid – how to avoid – avoid solvates