For monitoring the performance of the manufacturing process, the CGMP requires that a well-written procedure for in-process controls be established and followed. The in-process controls should be examined based on appropriate samples drawn from each batch. Appropriate samples are usually referred to as
representative samples drawn from respective raw materials, in-process materials, and lot or batch of the final product according to sampling plans as specified in CGMP or USP/NF. The objective of in-process controls is to control expected and/or unexpected sources of variabilities that may occur during the manufacturing process. When there is a deviation from established control specifications, the possible causes for deviation must be found and immediate corrective actions taken. In this chapter we focus on in-process controls for quality assurance of a manufacturing process. Unless otherwise specified, in-process controls are referred to as raw materials inspection, in-process materials quality assurance, and final product quality control and release targets.