Active pharmaceutical ingredient physical characteristics

For pharmaceutical scientists, the value in cocrystals would be if such materials would be superior active pharmaceutical ingredients relative to the drug substance itself. This possibility has been studied for the carbamazepine-saccharin cocrystal, where its performance characteristics were compared with the marketed form of carbamazepine [46]. It was learned that the physical and chemical stability of formulations containing the carbamazepine-saccharin cocrystal product were similar to those of carbamazepine in the marketed product, and comparative bioavailability studies demonstrated that the cocrystal was a viable alternative drug substance to the anhydrous drug form used in the conventional solid dose forms. 

By the time an active pharmaceutical ingredient (API) is made available to an analytical chemist in the formulation development group, most or all of the physical characteristics of an API has already been studied and the information should be available in some sort of a report from the drug substance group or preformulation group. Some of the key parameters that an analytical chemist in formulation development requires from such a report are the solubility and solution stability. 

Specification Established requirements for a raw material, packaging material, intermediate product, or active pharmaceutical ingredient in terms of its physical, chemical and (possibly) biological characteristics. 

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