Process Validation

Process validation is establishing documented evidence which provides a high degree of assurance that a specific process ( such as manufacture of pharmaceutical dosage forms) will consistently produce a product meeting its predetermined specifications and quality characteristics. THE MAIN REASONS FOR PROCESS VALIDATION ARE: 1. QUALITY ASSURANCE: Quality cannot be assured by daily quality control testing because of the limitations of statistical samples and the limited facilities of finished product testing. Validation checks the accuracy and reliability of a system or a process to meet the predetermined criteria. A successful validation provides high degree of assurance that a consistent level of quality is maintained in each unit of the finished product from one batch to another batch. 2. ECONOMICS: Due to successful validation, there is a decrease in the sampling and testing procedures and there are less number of product rejections and retesting. This lead to cost-saving benefits. 3. COMPLIANCE: For compliance to current good manufacturing practices CGMPs, validation is essential. ELEMENTS OF VALIDATION: Qualification is prior required condition for validation. The qualification includes the following steps: 1. Design Qualification (DQ) In this qualification, compliance of design with GMP should be demonstrated. The principles of design should be such as to achieve the objectives of GMP with regard to equipment. Mechanical drawings and design features provided by the manufacturer of the equipment should be examined. 2. Installation Qualification (IQ) Installation qualification should be carried out on new or modified facilities, systems and equipment. 3. Operational Qualification (OQ) Operational qualification should follow IQ, OQ should include the: Tests developed from the knowledge of the processes systems and equipment. 4. Performance Qualification (PQ): After IQ and OQ have been completed, the next qualification that should be completed is PQ. PQ should include the following: Tests using production materials, substitutes or simulated product. These can be developed from the knowledge of the process and facilities, systems or equipment. Before any batch from the process is commercially distributed to consumers,a manufacturer should have gained a high degree of assurance in the performance of the manufacturing process such that it will consistently produce APIs and drug products meeting those attributes relating to identity, strength, quality, purity, and potency.The assurance should be obtained from objective information and data from laboratory-,or commercial scale studies. TYPES OF PROCESS VALIDATION 1 PROSPECTIVE VALIDATION: This type of validation is performed before production, during a product’s development stage. A risk analysis is performed to assess the production process by breaking it down into separate steps. These are individually evaluated and based on past experience, the likelihood of each one leading to critical situations is determined. 2 CONCURRENT VALIDATION:This approach involves monitoring of critical processing steps and end product testing of current production, to show that the manufacturing process is in a state of control. You should monitor the first three batches produced on a production-scale as closely as possible. 3 RETROSPECTIVE VALIDATION Retrospective validation is used for facilities, processes, and process controls in operation that have not undergone a formally documented validation process. Validation of these facilities, processes, and process controls is possible using historical data to provide the necessary documentary evidence that the process is doing what it is believed to do. Therefore, this type of validation is only acceptable for well-established processes and will be inappropriate where there have been recent changes in the composition of product, operating processes, or equipment. Retrospective validation should not be considered a quality assurance measure, rather it should be performed only in certain circumstances,like when you’re introducing validation requirements for the first time. It is more useful for establishing priorities for validation, so avoid this technique for new products or processes. 4. REVALIDATION: Revalidation is essential for ensuring that any changes made to the process or its environment have not resulted in adverse effects on product quality or process characteristics.Conditions that require revalidation studies are: 1.Changes in Starting Materials  2.Changes in Packaging Material 3.Changes in Process 4.Changes in Equipment 5.Changes in Support System or Production Area