In January 2011 the FDA issued guidance entitled “Process Validation: General Principles and Practices,” which replaces the 1987 guidance . The guidance stresses lifecycle management, with the ability to store and retrieve data being important. The document describes three basic stages of process validation: process design, process qualification, and continued process verification. Design of experiments (DoE) and statistical process control (SPC) are urged. The document states that operations controlled by process analytical technology (PAT) may be preferred over non-PAT systems. The FDA urges readers to contact them with specific questions in areas not covered by this and related guidances.
In December 2010 Organic Process Research & Development posted a manuscript I wrote with two colleagues, entitled “Current Practices of Process Validation for Drug Substances and Intermediates.” . This manuscript is consistent with the current FDA guidance. Described in the manuscript are a number of previously unpublished examples of challenges and successes of implementing processes. More experienced process chemists and engineers may groan at some of these “war stories,” which can serve as valuable lessons.
 Guidance for Industry. Process Validation: General Principles and Practices” issued 1/24/2011 http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM070336.pdf
 Anderson, N. G.; Burdick, D. C.; Reeve, M. M. Org. Process Res. Dev. 2011, 15, 162.