ABSTRACT

Along with the fast developments in the drug production and control technologies, it has been easier to comment on the drug and its production, as well as observing/seeing the defects. These developments have brought within new arrangements in the regulations. Recently added ICH Q8, Q9, Q10 and Q11 guidelines have aimed to make the drug industry to develop rather an information based understanding towards the drug. Within this frame, especially during the drug formulation and active substance development studies, all factors that may affect the quality of the drug should be examined with scientific/statistical methods. For drug development that is compliant with the regulations, proper understanding and interpretation of new concepts explained in the guidelines are initially necessary. Some of these new concepts are Quality by Design (QbD), Critical Quality Attributes (CQA) and Critical Process Parameters (CPP). Each dosage form has its specific Design Space, Critical Quality Attributes and Critical Process Parameters. Correct determination of these parameters and values during the formulation development studies decreases the possible problems related to the drug throughout the drug’s life cycle and help them to be eliminated entirely. Therefore, it contributes to provide the quality that is expected from the drug.