Pharmaceutical Process Validation NASH

Copyright 2003 Marcel Dekker, Inc.

Previous edition: Pharmaceutical Process Validation: Second Edition, Revised and Expanded (I. R. Berry, R. A. Nash, eds.), 1993.

Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress. ISBN: 0-8247-0838-5 This book is printed on acid-free paper. Headquarters Marcel Dekker, Inc. 270 Madison Avenue, New York, NY 10016 tel: 212-696-9000; fax: 212-685-4540 Eastern Hemisphere Distribution Marcel Dekker AG Hutgasse 4, Postfach 812, CH-4001 Basel, Switzerland tel: 41-61-260-6300; fax: 41-61-260-6333 World Wide Web http://www.dekker.com The publisher offers discounts on this book when ordered in bulk quantities. For more information, write to Special Sales/Professional Marketing at the headquarters address above. Copyright 2003 by Marcel Dekker, Inc. All Rights Reserved. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher. Current printing (last digit): 10 9 8 7 6 5 4 3 2 1 PRINTED IN THE UNITED STATES OF AMERICA


DRUGS AND THE PHARMACEUTICAL SCIENCES

Executive Editor

James SwarbrickPharmaceuTech, Inc Pinehurst, North Carolina

Advisory BoardLarry L. Augsburger University of Maryland Baltimore, Maryland Douwe D. Breimer Gorlaeus Laboratories Leiden, The Netherlands David E. Nichols Purdue University West Lafayette, Indiana Stephen G. Schulman University of Florida Gamesville, Florida

Trevor M Jones The Association of the British Pharmaceutical Industry London, United KingdomHans E. Junginger Leiden/Amsterdam Center for Drug Research Leiden, The Netherlands Vincent H. L. Lee University of Southern California Los Angeles, California

Jerome P. Skelly Alexandria, Virginia

Felix Theeuwes Alza Corporation Palo Alto, California Geoffrey T Tucker University of Sheffield Royal Hallamshire Hospital Sheffield, United Kingdom

Peter G. Welling Institut de Recherche Jouvemal Fresnes, France


DRUGS AND THE PHARMACEUTICAL SCIENCES A Series of Textbooks and Monographs

1. Pharmacokmetics, Milo Gibaldi and Donald Perrier 2. Good Manufacturing Practices for Pharmaceuticals: A Plan for Total Quality Control, Sidney H. Willig, Murray M. Tuckerman, and William S. Hitchings IV 3. Microencapsulation, edited by J. R Nixon 4. Drug Metabolism. Chemical and Biochemical Aspects, Bernard Testa and Peter Jenner 5. New Drugs: Discovery and Development, edited by Alan A. Rubin 6. Sustained and Controlled Release Drug Delivery Systems, edited by Joseph R. Robinson 7. Modern Pharmaceutics, edited by Gilbert S. Banker and Christopher T. Rhodes 8. Prescription Drugs in Short Supply Case Histories, Michael A. Schwartz 9. Activated Charcoal' Antidotal and Other Medical Uses, David O. Cooney 10. Concepts in Drug Metabolism (in two parts), edited by Peter Jenner and Bernard Testa 11. Pharmaceutical Analysis: Modern Methods (in two parts), edited by James W, Munson 12. Techniques of Solubilization of Drugs, edited by Samuel H Yalkowsky 13. Orphan Drugs, edited by Fred E. Karch 14. Novel Drug Delivery Systems: Fundamentals, Developmental Concepts, Biomedical Assessments, Yie W. Chien 15. Pharmacokmetics: Second Edition, Revised and Expanded, Milo Gibaldi and Donald Perrier 16 Good Manufacturing Practices for Pharmaceuticals' A Plan for Total Quality Control, Second Edition, Revised and Expanded, Sidney H Willig, Murray M Tuckerman, and William S. Hitchings IV 17 Formulation of Veterinary Dosage Forms, edited by Jack Blodinger 18 Dermatological Formulations. Percutaneous Absorption, Brian W Barry 19. The Clinical Research Process in the Pharmaceutical Industry, edited by Gary M. Matoren 20. Microencapsulation and Related Drug Processes, Patrick B. Deasy 21. Drugs and Nutrients The Interactive Effects, edited by Daphne A. Roe and T. Colin Campbell 22. Biotechnology of Industrial Antibiotics, Enck J. Vandamme


23 Pharmaceutical Process Validation, edited by Bernard T Loftus and Robert A Nash 24 Anticancer and Interferon Agents Synthesis and Properties, edited by Raphael M Ottenbrtte and George B Butler 25 Pharmaceutical Statistics Practical and Clinical Applications, Sanford Bolton 26 Drug Dynamics for Analytical, Clinical, and Biological Chemists, Benjamin J Gudzmowicz, Burrows T Younkm, Jr, and Michael J Gudzmowicz 27 Modern Analysis of Antibiotics, edited by Adjoran Aszalos 28 Solubility and Related Properties, Kenneth C James 29 Controlled Drug Delivery Fundamentals and Applications, Second Edition, Revised and Expanded, edited by Joseph R Robinson and Vincent H Lee 30 New Drug Approval Process Clinical and Regulatory Management, edited by Richard A Guarino 31 Transdermal Controlled Systemic Medications, edited by Yie W Chien 32 Drug Delivery Devices Fundamentals and Applications, edited by Praveen Tyle 33 Pharmacokinetics Regulatory Industrial Academic Perspectives, edited by Peter G Welling and Francis L S Tse 34 Clinical Drug Trials and Tribulations, edited by Alien E Cato 35 Transdermal Drug Delivery Developmental Issues and Research Initiatives, edited by Jonathan Hadgraft and Richard H Guy 36 Aqueous Polymeric Coatings for Pharmaceutical Dosage Forms, edited by James W McGmity 37 Pharmaceutical Pelletization Technology, edited by Isaac GhebreSellassie 38 Good Laboratory Practice Regulations, edited by Alien F Hirsch 39 Nasal Systemic Drug Delivery, Yie W Chien, Kenneth S E Su, and Shyi-Feu Chang 40 Modern Pharmaceutics Second Edition, Revised and Expanded, edited by Gilbert S Banker and Chnstopher T Rhodes 41 Specialized Drug Delivery Systems Manufacturing and Production Technology, edited by Praveen Tyle 42 Topical Drug Delivery Formulations, edited by David W Osborne and Anton H Amann 43 Drug Stability Principles and Practices, Jens T Carstensen 44 Pharmaceutical Statistics Practical and Clinical Applications, Second Edition, Revised and Expanded, Sanford Bolton 45 Biodegradable Polymers as Drug Delivery Systems, edited by Mark Chasm and Robert Langer 46 Preclmical Drug Disposition A Laboratory Handbook, Francis L S Tse and James J Jaffe 47 HPLC in the Pharmaceutical Industry, edited by Godwin W Fong and Stanley K Lam 48 Pharmaceutical Bioequivalence, edited by Peter G Welling, Francis L S Tse, and Shrikant V Dinghe


49. Pharmaceutical Dissolution Testing, Umesh V. Sana/car 50. Novel Drug Delivery Systems: Second Edition, Revised and Expanded, Yie W. Chien 51. Managing the Clinical Drug Development Process, David M. Cocchetto and Ronald V. Nardi 52. Good Manufacturing Practices for Pharmaceuticals: A Plan for Total Quality Control, Third Edition, edited by Sidney H. Willig and James R. Stoker 53. Prodrugs: Topical and Ocular Drug Delivery, edited by Kenneth B. Sloan 54. Pharmaceutical Inhalation Aerosol Technology, edited by Anthony J. Mickey 55. Radiopharmaceuticals: Chemistry and Pharmacology, edited byAdrian D. Nunn

56. New Drug Approval Process: Second Edition, Revised and Expanded, edited by Richard A. Guarino 57. Pharmaceutical Process Validation: Second Edition, Revised and Expanded, edited by Ira R. Berry and Robert A. Nash58. Ophthalmic Drug Delivery Systems, edited byAshim K. Mitra

59. Pharmaceutical Skin Penetration Enhancement, edited by Kenneth A. Walters and Jonathan Hadgraft 60. Colonic Drug Absorption and Metabolism, edited by Peter R. Bieck 61. Pharmaceutical Particulate Carriers1 Therapeutic Applications, edited by Alain Rolland 62. Drug Permeation Enhancement: Theory and Applications, edited by Dean S. Hsieh 63. Glycopeptide Antibiotics, edited by Ramakrishnan Nagarajan 64. Achieving Sterility in Medical and Pharmaceutical Products, Nigel A. Halls 65. Multiparticulate Oral Drug Delivery, edited by Isaac Ghebre-Sellassie66. Colloidal Drug Delivery Systems, edited byJorg Kreuter 67 Pharmacokinetics: Regulatory Industrial Academic Perspectives,

Second Edition, edited by Peter G. Welling and Francis L. S. Tse68. Drug Stability: Principles and Practices, Second Edition, Revised and Expanded, Jens T. Carstensen

69. Good Laboratory Practice Regulations: Second Edition, Revised and Expanded, edited by Sandy Weinberg70. Physical Characterization of Pharmaceutical Solids, edited by Harry

G. Bnttain 71. Pharmaceutical Powder Compaction Technology, edited by Goran Alderborn and Christer Nystrom72. Modern Pharmaceutics. Third Edition, Revised and Expanded, edited

by Gilbert S. Banker and Christopher J Rhodes73. Microencapsulation. Methods and Industrial Applications, edited by Simon Benita

74. Oral Mucosal Drug Delivery, edited by Michael J. Rathbone75. Clinical Research in Pharmaceutical Development, edited by Barry Bleidt and Michael Montagne


76 The Drug Development Process Increasing Efficiency and Cost Effectiveness, edited by Peter G Welling, Louis Lasagna, and Umesh V Banakar 77 Microparticulate Systems for the Delivery of Proteins and Vaccines, edited by Smadar Cohen and Howard Bernstein 78 Good Manufacturing Practices for Pharmaceuticals A Plan for Total Quality Control, Fourth Edition, Revised and Expanded, Sidney H Willig and James R Stoker 79 Aqueous Polymeric Coatings for Pharmaceutical Dosage Forms Second Edition, Revised and Expanded, edited by James WMcGmity 80 Pharmaceutical Statistics Practical and Clinical Applications, Third Edition, Sanford Bolton 81 Handbook of Pharmaceutical Granulation Technology edited by Dilip M Pankh 82 Biotechnology of Antibiotics Second Edition, Revised and Expanded, edited by William R Strohl 83 Mechanisms of Transdermal Drug Delivery, edited by Russell O Potts and Richard H Guy 84 Pharmaceutical Enzymes edited by Albert Lauwers and Simon Scharpe 85 Development of Biopharmaceutical Parenteral Dosage Forms, edited by John A Bontempo 86 Pharmaceutical Project Management, edited by Tony Kennedy 87 Drug Products for Clinical Trials An International Guide to Formulation Production Quality Control, edited by Donald C Monkhouse and Christopher T Rhodes 88 Development and Formulation of Veterinary Dosage Forms Second Edition, Revised and Expanded, edited by Gregory E Hardee and J Desmond Baggot 89 Receptor-Based Drug Design, edited by Paul Leff 90 Automation and Validation of Information in Pharmaceutical Processing, edited by Joseph F deSpautz 91 Dermal Absorption and Toxicity Assessment, edited by Michael S Roberts and Kenneth A Walters 92 Pharmaceutical Experimental Design, Gareth A Lewis, Didier Mathieu, and Roger Phan-Tan-Luu 93 Preparing for FDA Pre-Approval Inspections, edited by Martin D Hynes III 94 Pharmaceutical Excipients Characterization by IR, Raman, and NMR Spectroscopy, David E Bugay and W Paul Fmdlay 95 Polymorphism in Pharmaceutical Solids, edited by Harry G Brittam 96 Freeze-Drymg/Lyophihzation of Pharmaceutical and Biological Products, edited by Louis Rey and Joan C May 97 Percutaneous Absorption Drugs-Cosmetics-Mechanisms-Methodology, Third Edition, Revised and Expanded, edited by Robert L Bronaugh and Howard I Maibach


98. Bioadhesive Drug Delivery Systems: Fundamentals, Novel Approaches, and Development, edited by Edith Mathiowitz, Donald E. Chtckering III, and Claus-Michael Lehr 99. Protein Formulation and Delivery, edited by Eugene J. McNally 100. New Drug Approval Process: Third Edition, The Global Challenge, edited by Richard A. Guarino 101. Peptide and Protein Drug Analysis, edited by Ronald E. Reid 102 Transport Processes in Pharmaceutical Systems, edited by Gordon L Amidon, Ping I. Lee, and Elizabeth M. Topp 103. Excipient Toxicity and Safety, edited by Myra L. Weiner and Lois A. Kotkoskie 104 The Clinical Audit in Pharmaceutical Development, edited by Michael R. Hamrell 105. Pharmaceutical Emulsions and Suspensions, edited by Francoise Nielloud and Gilberte Marti-Mestres 106. Oral Drug Absorption: Prediction and Assessment, edited by Jennifer B. Dressman and Hans Lennernas 107. Drug Stability: Principles and Practices, Third Edition, Revised and Expanded, edited by Jens T. Carstensen and C. T. Rhodes 108. Containment in the Pharmaceutical Industry, edited by James P. Wood 109. Good Manufacturing Practices for Pharmaceuticals: A Plan for Total Quality Control from Manufacturer to Consumer, Fifth Edition, Revised and Expanded, Sidney H Willig 110. Advanced Pharmaceutical Solids, Jens T Carstensen 111. Endotoxins: Pyrogens, LAL Testing, and Depyrogenation, Second Edition, Revised and Expanded, Kevin L. Williams 112 Pharmaceutical Process Engineering, Anthony J. Hickey and David Ganderton 113. Pharmacogenomics, edited by Werner Kalow, Urs A. Meyer, and Rachel F. Tyndale 114. Handbook of Drug Screening, edited by Ramaknshna Seethala and Prabhavathi B. Fernandas 115. Drug Targeting Technology: Physical Chemical Biological Methods, edited by Hans Schreier 116. Drug-Drug Interactions, edited by A. David Rodngues 117. Handbook of Pharmaceutical Analysis, edited by Lena Ohannesian and Anthony J. Streeter 118. Pharmaceutical Process Scale-Up, edited by Michael Levin 119. Dermatological and Transdermal Formulations, edited by Kenneth A. Walters 120. Clinical Drug Trials and Tribulations: Second Edition, Revised and Expanded, edited by Alien Cato, Lynda Sutton, and Alien Cato III 121. Modern Pharmaceutics: Fourth Edition, Revised and Expanded, edited by Gilbert S. Banker and Chnstopher T. Rhodes 122. Surfactants and Polymers in Drug Delivery, Martin Malmsten 123. Transdermal Drug Delivery: Second Edition, Revised and Expanded, edited by Richard H. Guy and Jonathan Hadgraft


Good Laboratory Practice Regulations: Second Edition, Revised and Expanded, edited by Sandy Weinberg 125. Parenteral Quality Control: Sterility, Pyrogen, Particulate, and Package Integrity Testing. Third Edition, Revised and Expanded, Michael J. Akers, Daniel S. Larnmore, and Dana Morion Guazzo 126. Modified-Release Drug Delivery Technology, edited by Michael J. Rathbone, Jonathan Hadgraft, and Michael S. Roberts 127. Simulation for Designing Clinical Trials' A Pharmacokinetic-Pharmacodynamic Modeling Perspective, edited by Hui C Kimko and Stephen B Duffull 128. Affinity Capillary Electrophoresis in Pharmaceutics and Biopharmaceutics, edited by Remhard H. H. Neubert and Hans-Hermann Ruttinger 129. Pharmaceutical Process Validation: An International Third Edition, Revised and Expanded, edited by Robert A Nash and Alfred H. Wachter 130. Ophthalmic Drug Delivery Systems: Second Edition, Revised and Expanded, edited byAshim K. Mitra 131 Pharmaceutical Gene Delivery Systems, edited by Alam Rolland and Sean M. SullivanADDITIONAL VOLUMES IN PREPARATION

124.

Biomarkers in Clinical Drug Development, edited by John C Bloom and Robert A. DeanPharmaceutical Inhalation Aerosol Technology: Second Edition, Revised and Expanded, edited by Anthony J Mickey

Pharmaceutical Extrusion Technology, edited by Isaac Ghebre-Sellassie and Charles MartinPharmaceutical Compliance, edited by Carmen Medina


Dedicated to Theodore E. Byers, formerly of the U.S. Food and Drug Administration, and Heinz Sucker, Professor at the University of Berne, Switzerland, for their pioneering contributions with respect to the pharmaceutical process validation concept. We also acknowledge the past contributions of Bernard T. Loftus and Ira R. Berry toward the success of Pharmaceutical Process Validation.


Preface

The third edition of Pharmaceutical Process Validation represents a new approach to the topic in several important respects. Many of us in the field had made the assumption that pharmaceutical process validation was an American invention, based on the pioneering work of Theodore E. Byers and Bernard T. Loftus, both formerly with the U.S. Food & Drug Administration. The truth is that many of our fundamental concepts of pharmaceutical process validation came to us from Validation of Manufacturing Processes, Fourth European Seminar on Quality Control, September 25, 1980, Geneva, Switzerland, and Validation in Practice, edited by H. Sucker, Wissenschaftliche Verlagsegesellschaft, GmbH, Stuttgard, Germany, 1983. There are new chapters in this edition that will add to the books impact. They include Validation for Medical Devices by Nishihata, Validation of Biotechnology Processes by Sofer, Transdermal Process Validation by Neal, Integrated Packaging Validation by Frederick, Statistical Methods for Uniformity and Dissolution Testing by Bergum and Utter, Change Control and SUPAC by Waterland and Kowtna, Validation in Contract Manufacturing by Parikh, and Harmonization, GMPs, and Validation by Wachter. I am pleased to have Dr. Alfred Wachter join me as coeditor of this edition. He was formerly head of Pharmaceutical Product Development for the CIBA Pharmaceutical Company in Basel, Switzerland, and also spent a number of years on assignment in Asia for CIBA. Fred brings a very strong international perspective to the subject matter. Robert A. Nash


ContentsPreface Contributors Introduction 1. Regulatory Basis for Process Validation John M. Dietrick and Bernard T. Loftus 2. Prospective Process Validation Allen Y. Chao, F. St. John Forbes, Reginald F. Johnson, and Paul Von Doehren 3. Retrospective Validation Chester J. Trubinski 4. Sterilization Validation Michael J. Akers and Neil R. Anderson 5. Validation of Solid Dosage Forms Jeffrey S. Rudolph and Robert J. Sepelyak 6. Validation for Medical Devices Toshiaki Nishihata 7. Validation of Biotechnology Processes Gail Sofer 8. Transdermal Process Validation Charlie Neal, Jr. 9. Validation of Lyophilization Edward H. Trappler


10. Validation of Inhalation Aerosols Christopher J. Sciarra and John J. Sciarra 11. Process Validation of Pharmaceutical Ingredients Robert A. Nash 12. Qualification of Water and Air Handling Systems Kunio Kawamura 13. Equipment and Facility Qualification Thomas L. Peither 14. Validation and Verification of Cleaning Processes William E. Hall 15. Validation of Analytical Methods and Processes Ludwig Huber 16. Computer System Validation: Controlling the Manufacturing Process Tony de Claire 17. Integrated Packaging Validation Mervyn J. Frederick 18. Analysis of Retrospective Production Data Using Quality Control Charts Peter H. Cheng and John E. Dutt 19. Statistical Methods for Uniformity and Dissolution Testing James S. Bergum and Merlin L. Utter 20. Change Control and SUPAC Nellie Helen Waterland and Christopher C. Kowtna 21. Process Validation and Quality Assurance Carl B. Rifino 22. Validation in Contract Manufacturing Dilip M. Parikh 23. Terminology of Nonaseptic Process Validation Kenneth G. Chapman 24. Harmonization, GMPs, and Validation Alfred H. Wachter


Contributors

Michael J. Akers Baxter Pharmaceutical Solutions, Bloomington, Indiana, U.S.A. Neil R. Anderson Eli Lilly and Company, Indianapolis, Indiana, U.S.A. James S. Bergum Bristol-Myers Squibb Company, New Brunswick, New Jersey, U.S.A. Kenneth G. Chapman Drumbeat Dimensions, Inc., Mystic, Connecticut, U.S.A. Allen Y. Chao Watson Labs, Carona, California, U.S.A. Peter H. Cheng New York State Research Foundation for Mental Hygiene, New York, New York, U.S.A. Tony de Claire APDC Consulting, West Sussex, England John M. Dietrick Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Rockville, Maryland, U.S.A. John E. Dutt EM Industries, Inc., Hawthorne, New York, U.S.A. Mervyn J. Frederick NV OrganonAkzo Nobel, Oss, The Netherlands William E. Hall Hall & Pharmaceutical Associates, Inc., Kure Beach, North Carolina, U.S.A. Ludwig Huber Agilent Technologies GmbH, Waldbronn, Germany


F. St. John Forbes Wyeth Labs, Pearl River, New York, U.S.A. *Reginald F. Johnson Searle & Co., Inc., Skokie, Illinois, U.S.A. Kunio Kawamura Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan Christopher C. Kowtna DuPont Pharmaceuticals Co., Wilmington, Delaware, U.S.A. *Bernard T. Loftus Bureau of Drugs, U.S. Food and Drug Administration, Washington, D.C., U.S.A. Robert A. Nash Stevens Institute of Technology, Hoboken, New Jersey, U.S.A. Charlie Neal, Jr. Diosynth-RTP, Research Triangle Park, North Carolina, U.S.A. Toshiaki Nishihata Santen Pharmaceutical Co., Ltd., Osaka, Japan Dilip M. Parikh APACE PHARMA Inc., Westminster, Maryland, U.S.A. Thomas L. Peither PECONPeither Consulting, Schopfheim, Germany Carl B. Rifino AstraZeneca Pharmaceuticals LP, Newark, Delaware, U.S.A. Jeffrey S. Rudolph Pharmaceutical Consultant, St. Augustine, Florida, U.S.A. Christopher J. Sciarra Sciarra Laboratories Inc., Hicksville, New York, U.S.A. John J. Sciarra Sciarra Laboratories Inc., Hicksville, New York, U.S.A. Robert J. Sepelyak AstraZeneca Pharmaceuticals LP, Wilmington, Delaware, U.S.A. Gail Sofer BioReliance, Rockville, Maryland, U.S.A. Edward H. Trappler Lyophilization Technology, Inc., Warwick, Pennsylvania, U.S.A.

*Retired


Chester J. Trubinski Church & Dwight Co., Inc., Princeton, New Jersey, U.S.A. Merlin L. Utter Wyeth Pharmaceuticals, Pearl River, New York, U.S.A. Paul Von Doehren Searle & Co., Inc., Skokie, Illinois, U.S.A. Alfred H. Wachter Wachter Pharma Projects, Therwil, Switzerland Nellie Helen Waterland ware, U.S.A. DuPont Pharmaceuticals Co., Wilmington, Dela-


IntroductionRobert A. NashStevens Institute of Technology, Hoboken, New Jersey, U.S.A.

I. FDA GUIDELINES The U.S. Food and Drug Administration (FDA) has proposed guidelines with the following definition for process validation [1]:Process validation is establishing documented evidence which provides a high degree of assurance that a specific process (such as the manufacture of pharmaceutical dosage forms) will consistently produce a product meeting its predetermined specifications and quality characteristics.

According to the FDA, assurance of product quality is derived from careful and systemic attention to a number of important factors, including: selection of quality components and materials, adequate product and process design, and (statistical) control of the process through in-process and end-product testing. Thus, it is through careful design (qualification) and validation of both the process and its control systems that a high degree of confidence can be established that all individual manufactured units of a given batch or succession of batches that meet specifications will be acceptable. According to the FDAs Current Good Manufacturing Practices (CGMPs) 21CFR 211.110 a:Control procedures shall be established to monitor output and to validate performance of the manufacturing processes that may be responsible for causing variability in the characteristics of in-process material and the drug product. Such control procedures shall include, but are not limited to the following, where appropriate [2]: 1. Tablet or capsule weight variation 2. Disintegration time


3. Adequacy of mixing to assure uniformity and homogeneity 4. Dissolution time and rate 5. Clarity, completeness, or pH of solutions

The first four items listed above are directly related to the manufacture and validation of solid dosage forms. Items 1 and 3 are normally associated with variability in the manufacturing process, while items 2 and 4 are usually influenced by the selection of the ingredients in the product formulation. With respect to content uniformity and unit potency control (item 3), adequacy of mixing to assure uniformity and homogeneity is considered a high-priority concern. Conventional quality control procedures for finished product testing encompass three basic steps: 1. Establishment of specifications and performance characteristics 2. Selection of appropriate methodology, equipment, and instrumentation to ensure that testing of the product meets specifications 3. Testing of the final product, using validated analytical and testing methods to ensure that finished product meets specifications. With the emergence of the pharmaceutical process validation concept, the following four additional steps have been added: 4. Qualification of the processing facility and its equipment 5. Qualification and validation of the manufacturing process through appropriate means 6. Auditing, monitoring, sampling, or challenging the key steps in the process for conformance to in-process and final product specifications 7. Revalidation when there is a significant change in either the product or its manufacturing process [3].

II. TOTAL APPROACH TO PHARMACEUTICAL PROCESS VALIDATION It has been said that there is no specific basis for requiring a separate set of process validation guidelines, since the essentials of process validation are embodied within the purpose and scope of the present CGMP regulations [2]. With this in mind, the entire CGMP document, from subpart B through subpart K, may be viewed as being a set of principles applicable to the overall process of manufacturing, i.e., medical devices (21 CFRPart 820) as well as drug products, and thus may be subjected, subpart by subpart, to the application of the principles of qualification, validation, verification and control, in addition to change control and revalidation, where applicable. Although not a specific re-


quirement of current regulations, such a comprehensive approach with respect to each subpart of the CGMP document has been adopted by many drug firms. A checklist of qualification and control documentation with respect to CGMPs is provided in Table 1. A number of these topics are discussed separately in other chapters of this book.

III. WHY ENFORCE PROCESS VALIDATION? The FDA, under the authority of existing CGMP regulations, guidelines [1], and directives [3], considers process validation necessary because it makes good engineering sense. The basic concept, according to Mead [5], has long been

Table 1 Checklist of Qualification and Control DocumentationQualification and control documentation

SubpartA B C

Section of CGMPsGeneral provisions Organization and personnel Buildings and facilities

D E F

Equipment Control of components, containers and closures Production and process controls

G H I

Packaging and labeling controls Holding and distribution Laboratory controls

J K

Records and reports Return and salvaged drug products

Responsibilities of the quality control unit Plant and facility installation and qualification Maintenance and sanitation Microbial and pest control Installation and qualification of equipment and cleaning methods Incoming component testing procedures Process control systems, reprocessing control of microbial contamination Depyrogenation, sterile packaging, filling and closing, expire dating Warehousing and distribution procedures Analytical methods, testing for release component testing and stability testing Computer systems and information systems Batch reprocessing

Sterilization procedures, Air and water quality are covered in appropriate subparts of Table 1.


applied in other industries, often without formal recognition that such a concept was being used. For example, the terms reliability engineering and qualification have been used in the past by the automotive and aerospace industries to represent the process validation concept. The application of process validation should result in fewer product recalls and troubleshooting assignments in manufacturing operations and more technically and economically sound products and their manufacturing processes. In the old days R & D gurus would literally hand down the go sometimes overformulated product and accompanying obtuse manufacturing procedure, usually with little or no justification or rationale provided. Today, under FDAs Preapproval Inspection (PAI) program [4] such actions are no longer acceptable. The watchword is to provide scientifically sound justifications (including qualification and validation documentation) for everything that comes out of the pharmaceutical R & D function.

IV. WHAT IS PROCESS VALIDATION? Unfortunately, there is still much confusion as to what process validation is and what constitutes process validation documentation. At the beginning of this introduction several different definitions for process validation were provided, which were taken from FDA guidelines and the CGMPs. Chapman calls process validation simply organized, documented common sense [6]. Others have said that it is more than three good manufactured batches and should represent a lifetime commitment as long as the product is in production, which is pretty much analogous to the retrospective process validation concept. The big problem is that we use the term validation generically to cover the entire spectrum of CGMP concerns, most of which are essentially people, equipment, component, facility, methods, and procedural qualification. The specific term process validation should be reserved for the final stage(s) of the product/process development sequence. The essential or key steps or stages of a successfully completed product/process development program are presented in Table 2 [7]. The end of the sequence that has been assigned to process validation is derived from the fact that the specific exercise of process validation should never be designed to fail. Failure in carrying out the process validation assignment is often the result of incomplete or faulty understanding of the processs capability, in other words, what the process can and cannot do under a given set of operational circumstances. In a well-designed, well-run overall validation program, most of the budget dollars should be spent on equipment, component, facility, methods qualification, and process demonstration, formerly called process qualification. In such a program, the formalized final process validation


Table 2 The Key Stages in the Product/Process Development SequenceDevelopment stageProduct design Product characterization Product selection (go formula) Process design Product optimization Process characterization Process optimization Process demonstration Process validation program Product/process certification

Pilot scale-up phase1 batch size

10 batch size 100 batch size

With the exception of solution products, the bulk of the work is normally carried out at 10 batch size, which is usually the first scale-up batches in production-type equipment.

sequence provides only the necessary process validation documentation required by the regulatory authoritiesin other words, the Good Housekeeping Seal of Approval, which shows that the manufacturing process is in a state of control. Such a strategy is consistent with the U.S. FDAs preapproval inspection program [4], wherein the applicant firm under either a New Drug Application (NDA) or an Abbreviated New Drug Application (ANDA) submission must show the necessary CGMP information and qualification data (including appropriate development reports), together with the formal protocol for the forthcoming full-scale, formal process validation runs required prior to product launch. Again, the term validation has both a specific meaning and a general one, depending on whether the word process is used. Determine during the course of your reading whether the entire concept is discussed in connection with the topici.e., design, characterization, optimization, qualification, validation, and/ or revalidationor whether the author has concentrated on the specifics of the validation of a given product and/or its manufacturing process. In this way the text will take on greater meaning and clarity.

V. PILOT SCALE-UP AND PROCESS VALIDATION The following operations are normally carried out by the development function prior to the preparation of the first pilot-production batch. The development activities are listed as follows:


1. 2. 3. 4.

Formulation design, selection, and optimization Preparation of the first pilot-laboratory batch Conduct initial accelerated stability testing If the formulation is deemed stable, preparation of additional pilotlaboratory batches of the drug product for expanded nonclinical and/ or clinical use.

The pilot program is defined as the scale-up operations conducted subsequent to the product and its process leaving the development laboratory and prior to its acceptance by the full scale manufacturing unit. For the pilot program to be successful, elements of process validation must be included and completed during the developmental or pilot laboratory phase of the work. Thus, product and process scale-up should proceed in graduated steps with elements of process validation (such as qualifications) incorporated at each stage of the piloting program [9,10].

A. Laboratory Batch The first step in the scale-up process is the selection of a suitable preliminary formula for more critical study and testing based on certain agreed-upon initial design criteria, requirements, and/or specifications. The work is performed in the development laboratory. The formula selected is designated as the (1 ) laboratory batch. The size of the (1 ) laboratory batch is usually 310 kg of a solid or semisolid, 310 liters of a liquid, or 3000 to 10,000 units of a tablet or capsule.

B. Laboratory Pilot Batch After the (1 ) laboratory batch is determined to be both physically and chemically stable based on accelerated, elevated temperature testing (e.g., 1 month at 45C or 3 months at 40C or 40C/80% RH), the next step in the scale-up process is the preparation of the (10 ) laboratory pilot batch. The (10 ) laboratory pilot batch represents the first replicated scale-up of the designated formula. The size of the laboratory pilot batch is usually 30100 kg, 30100 liters, or 30,000 to 100,000 units. It is usually prepared in small pilot equipment within a designated CGMPapproved area of the development laboratory. The number and actual size of the laboratory pilot batches may vary in response to one or more of the following factors: 1. Equipment availability 2. Active pharmaceutical ingredient (API)


3. Cost of raw materials 4. Inventory requirements for clinical and nonclinical studies Process demonstration or process capability studies are usually started in this important second stage of the pilot program. Such capability studies consist of process ranging, process characterization, and process optimization as a prerequisite to the more formal validation program that follows later in the piloting sequence. C. Pilot Production The pilot-production phase may be carried out either as a shared responsibility between the development laboratories and its appropriate manufacturing counterpart or as a process demonstration by a separate, designated pilot-plant or process-development function. The two organization piloting options are presented separately in Figure 1. The creation of a separate pilot-plant or processdevelopment unit has been favored in recent years because it is ideally suited to carry out process scale-up and/or validation assignments in a timely manner. On the other hand, the joint pilot-operation option provides direct communication between the development laboratory and pharmaceutical production.

Figure 1 Main piloting options. (Top) Separate pilot plant functionsengineering concept. (Bottom) Joint pilot operation.


The object of the pilot-production batch is to scale the product and process by another order of magnitude (100 ) to, for example, 3001,000 kg, 300 1,000 liters, or 300,0001,000,000 dosage form units (tablets or capsules) in size. For most drug products this represents a full production batch in standard production equipment. If required, pharmaceutical production is capable of scaling the product/process to even larger batch sizes should the product require expanded production output. If the batch size changes significantly, additional validation studies would be required. The term product/process is used, since one cant describe a product with discussing its process of manufacture and, conversely, one cant talk about a process without describing the product being manufactured. Usually large production batch scale-up is undertaken only after product introduction. Again, the actual size of the pilot-production (100 ) batch may vary due to equipment and raw material availability. The need for additional pilot-production batches ultimately depends on the successful completion of a first pilot batch and its process validation program. Usually three successfully completed pilot-production batches are required for validation purposes. In summary, process capability studies start in the development laboratories and/or during product and process development, and continue in welldefined stages until the process is validated in the pilot plant and/or pharmaceutical production. An approximate timetable for new product development and its pilot scale-up program is suggested in Table 3.

VI. PROCESS VALIDATION: ORDER OF PRIORITY Because of resource limitation, it is not always possible to validate an entire companys product line at once. With the obvious exception that a companys most profitable products should be given a higher priority, it is advisable to draw up a list of product categories to be validated. The following order of importance or priority with respect to validation is suggested:

A. Sterile Products and Their Processes 1. Large-volume parenterals (LVPs) 2. Small-volume parenterals (SVPs) 3. Ophthalmics, other sterile products, and medical devices


Table 3 Approximate Timetable for New Product Development and Pilot Scale-Up TrialsCalendar months24 24 34 13 14 34

EventFormula selection and development Assay methods development and formula optimization Stability in standard packaging 3-month readout (1 size) Pilot-laboratory batches (10 size) Preparation and release of clinical supplies (10 size) and establishment of process demonstration Additional stability testing in approved packaging 68-month readout (1 size) 3-month readout (10 size) Validation protocols and pilot batch request Pilot-production batches (100 size) Additional stability testing in approved packaging 912-month readout (1 size) 68-month readout (10 size) 3-month readout (100 size) Interim approved technical product development report with approximately 12 months stability (1 size) Totals

13 13 34

13 1836

B. Nonsterile Products and Their Processes 1. Low-dose/high-potency tablets and capsules/transdermal delivery systems (TDDs) 2. Drugs with stability problems 3. Other tablets and capsules 4. Oral liquids, topicals, and diagnostic aids

VII. WHO DOES PROCESS VALIDATION? Process validation is done by individuals with the necessary training and experience to carry out the assignment. The specifics of how a dedicated group, team, or committee is organized to conduct process validation assignments is beyond the scope of this introductory chapter. The responsibilities that must be carried out and the organizational structures best equipped to handle each assignment are outlined in Table 4. The


Table 4 Specific Responsibilities of Each Organizational Structure within the Scope of Process ValidationEngineering Development Install, qualify, and certify plant, facilities, equipment, and support system. Design and optimize manufacturing process within design limits, specifications, and/or requirementsin other words, the establishment of process capability information. Operate and maintain plant, facilities, equipment, support systems, and the specific manufacturing process within its design limits, specifications, and/or requirements. Establish approvable validation protocols and conduct process validation by monitoring, sampling, testing, challenging, and/ or auditing the specific manufacturing process for compliance with design limits, specifications, and/or requirements.

Manufacturing

Quality assurance

Source: Ref. 8.

best approach in carrying out the process validation assignment is to establish a Chemistry, Manufacturing and Control (CMC) Coordination Committee at the specific manufacturing plant site [10]. Representation on such an important logistical committee should come from the following technical operations: Formulation development (usually a laboratory function) Process development (usually a pilot plant function) Pharmaceutical manufacturing (including packaging operations) Engineering (including automation and computer system responsibilities) Quality assurance Analytical methods development and/or Quality Control API Operations (representation from internal operations or contract manufacturer) Regulatory Affairs (technical operations representative) IT (information technology) operations

The chairperson or secretary of such an important site CMC Coordination Committee should include the manager of process validation operations. Typical meeting agendas may include the following subjects in the following recommended order of priority: Specific CGMP issues for discussion and action to be taken Qualification and validation issues with respect to a new product/process


Technology transfer issues within or between plant sites. Pre-approval inspection (PAI) issues of a forthcoming product/process Change control and scale-up, post approval changes (SUPAC) with respect to current approved product/process [11].

VIII. PROCESS DESIGN AND CHARACTERIZATION Process capability is defined as the studies used to determine the critical process parameters or operating variables that influence process output and the range of numerical data for critical process parameters that result in acceptable process output. If the capability of a process is properly delineated, the process should consistently stay within the defined limits of its critical process parameters and product characteristics [12]. Process demonstration formerly called process qualification, represents the actual studies or trials conducted to show that all systems, subsystems, or unit operations of a manufacturing process perform as intended; that all critical process parameters operate within their assigned control limits; and that such studies and trials, which form the basis of process capability design and testing, are verifiable and certifiable through appropriate documentation. The manufacturing process is briefly defined as the ways and means used to convert raw materials into a finished product. The ways and means also include people, equipment, facilities, and support systems required to operate the process in a planned and effectively managed way. All the latter functions must be qualified individually. The master plan or protocol for process capability design and testing is presented in Table 5. A simple flow chart should be provided to show the logistical sequence of unit operations during product/process manufacture. A typical flow chart used in the manufacture of a tablet dosage form by the wet granulation method is presented in Figure 2.

IX. STREAMLINING VALIDATION OPERATIONS The best approach to avoiding needless and expensive technical delays is to work in parallel. The key elements at this important stage of the overall process are the API, analytical test methods, and the drug product (pharmaceutical dosage form). An integrated and parallel way of getting these three vitally important functions to work together is depicted in Figure 3. Figure 3 shows that the use of a single analytical methods testing function is an important technical bridge between the API and the drug product development functions as the latter two move through the various stages of develop-


Table 5 Master Plan or Protocol for Process Capability Design and TestingObjective Types of process Typical processes Process definition Definition of process output Definition of test methods Process analysis Pilot batch trials Pilot batch replication Process redefinition Process capability evaluation Final report Process capability design and testing Batch, intermittent, continuous Chemical, pharmaceutical, biochemical Flow diagram, in-process, finished product Potency, yield, physical parameters Instrumentation, procedures, precision, and accuracy Process variables, matrix design, factorial design analysis Define sampling and testing, stable, extended runs Different days, different materials, different equipment Reclassification of process variables Stability and variability of process output, economic limits Recommended SOP, specifications, and process limits

Figure 2 Process flow diagram for the manufacture of a tablet dosage form by wet granulation method. The arrows show the transfer of material into and out of each of the various unit operations. The information in parentheses indicates additions of material to specific unit operations. A list of useful pharmaceutical unit operations is presented in Table 6.


Table 6 A List of Useful Pharmaceutical Unit Operations According to CategoriesHeat transfer processes: Cooking, cooling, evaporating, freezing, heating, irradiating, sterilizing, freeze-drying Change in state: Crystallizing, dispersing, dissolving, immersing, freeze-drying, neutralizing Change in size: Agglomerating, blending, coating, compacting, crushing, crystallizing, densifying, emulsifying, extruding, flaking, flocculating, grinding, homogenizing, milling, mixing, pelletizing, pressing, pulverizing, precipitating, sieving Moisture transfer processes: Dehydrating, desiccating, evaporating, fluidizing, humidifying, freeze-drying, washing, wetting Separation processes: Centrifuging, clarifying, deareating, degassing, deodorizing, dialyzing, exhausting, extracting, filtering, ion exchanging, pressing, sieving, sorting, washing Transfer processes: Conveying, filling, inspecting, pumping, sampling, storing, transporting, weighingSource: Ref. 13.

ment, clinical study, process development, and process validation and into production. Working individually with separate analytical testing functions and with little or no appropriate communication among these three vital functions is a prescription for expensive delays. It is important to remember that the concept illustrated in Figure 3 can still be followed even when the API is sourced from outside the plant site or company. In this particular situation there will probably be two separate analytical methods development functions: one for the API manufacturer and one for the drug product manufacturer [14].

X. STATISTICAL PROCESS CONTROL AND PROCESS VALIDATION Statistical process control (SPC), also called statistical quality control and process validation (PV), represents two sides of the same coin. SPC comprises the various mathematical tools (histogram, scatter diagram run chart, and control chart) used to monitor a manufacturing process and to keep it within in-process and final product specification limits. Lord Kelvin once said, When you can measure what you are speaking about, and express it in numbers, then you know something about it. Such a thought provides the necessary link between the two concepts. Thus, SPC represents the tools to be used, while PV represents the procedural environment in which those tools are used.


Figure 3 Working in parallel. (Courtesy of Austin Chemical Co., Inc.)

There are three ways of establishing quality products and their manufacturing processes: 1. In-process and final product testing, which normally depends on sampling size (the larger the better). In some instances, nothing short of excessive sampling can ensure reaching the desired goal, i.e., sterility testing. 2. Establishment of tighter (so called in-house) control limits that hold the product and the manufacturing process to a more demanding stan-


dard will often reduce the need for more extensive sampling requirements. 3. The modern approach, based on Japanese quality engineering [15], is the pursuit of zero defects by applying tighter control over process variability (meeting a so-called 6 sigma standard). Most pharmaceutical products and their manufacturing processes in the United States today, with the exception of sterile processes are designed to meet a 4 sigma limit (which would permit as many as eight defects per 1000 units). The new approach is to center the process (in which the grand average is roughly equal to 100% of label potency or the target value of a given specification) and to reduce the process variability or noise around the mean or to achieve minimum variability by holding both to the new standard, batch after batch. In so doing, a 6 sigma limit may be possible (which is equivalent to not more than three to four defects per 1 million units), also called zero defects. The goal of 6 sigma, zero defects is easier to achieve for liquid than for solid pharmaceutical dosage forms [16]. Process characterization represents the methods used to determine the critical unit operations or processing steps and their process variables, that usually affect the quality and consistency of the product outcomes or product attributes. Process ranging represents studies that are used to identify critical process or test parameters and their respective control limits, which normally affect the quality and consistency of the product outcomes of their attributes. The following process characterization techniques may be used to designate critical unit operations in a given manufacturing process. A. Constraint Analysis One procedure that makes subsystem evaluations and performance qualification trials manageable is the application of constraint analysis. Boundary limits of any technology and restrictions as to what constitutes acceptable output from unit operations or process steps should in most situations constrain the number of process variables and product attributes that require analysis. The application of the constraint analysis principle should also limit and restrict the operational range of each process variable and/or specification limit of each product attribute. Information about constraining process variables usually comes from the following sources: Previous successful experience with related products/processes Technical and engineering support functions and outside suppliers Published literatures concerning the specific technology under investigation


A practical guide to constraint analysis comes to us from the application of the Pareto Principle (named after an Italian sociologist) and is also known as the 8020 rule, which simply states that about 80% of the process output is governed by about 20% of the input variables and that our primary job is to find those key variables that drive the process. The FDA in their proposed amendments to the CGMPs [17] have designated that the following unit operations are considered critical and therefore their processing variables must be controlled and not disregarded: Cleaning Weighing/measuring Mixing/blending Compression/encapsulation Filling/packaging/labeling

B. Fractional Factorial Design An experimental design is a series of statistically sufficient qualification trials that are planned in a specific arrangement and include all processing variables that can possibly affect the expected outcome of the process under investigation. In the case of a full factorial design, n equals the number of factors or process variables, each at two levels, i.e., the upper (+) and lower () control limits. Such a design is known as a 2n factorial. Using a large number of process variables (say, 9) we could, for example, have to run 29, or 512, qualification trials in order to complete the full factorial design. The fractional factorial is designed to reduce the number of qualification trials to a more reasonable number, say, 10, while holding the number of randomly assigned processing variables to a reasonable number as well, say, 9. The technique was developed as a nonparametric test for process evaluation by Box and Hunter [18] and reviewed by Hendrix [19]. Ten is a reasonable number of trials in terms of resource and time commitments and should be considered an upper limit in a practical testing program. This particular design as presented in Table 7 does not include interaction effects.

XI. OPTIMIZATION TECHNIQUES Optimization techniques are used to find either the best possible quantitative formula for a product or the best possible set of experimental conditions (input values) needed to run the process. Optimization techniques may be employed in the laboratory stage to develop the most stable, least sensitive formula, or in the qualification and validation stages of scale-up in order to develop the most sta-


Table 7 Fractional Factorial Design (9 Variables in 10 Experiments)Trial no.1 2 3 4 5 6 7 8 9 10

X1 + + + + +

X2 + + + + +

X3 + + + + +

X4 + + + + +

X5 + + + + +

X6 + + + + +

X7 + + + + +

X8 + + + + +

X9 + + + + +

Worst-case conditions: Trial 1 (lower control limit). Trial 10 (upper control limit). X variables randomly assigned. Best values to use are RSD of data set for each trial. When adding up the data by columns, + and are now numerical values and the sum is divided by 5 (number of +s or s). If the variable is not significant, the sum will approach zero.

ble, least variable, robust process within its proven acceptable range(s) of operation, Chapmans so-called proven acceptable range (PAR) principle [20]. Optimization techniques may be classified as parametric statistical methods and nonparametric search methods. Parametric statistical methods, usually employed for optimization, are full factorial designs, half factorial designs, simplex designs, and Lagrangian multiple regression analysis [21]. Parametric methods are best suited for formula optimization in the early stages of product development. Constraint analysis, described previously, is used to simplify the testing protocol and the analysis of experimental results. The steps involved in the parametric optimization procedure for pharmaceutical systems have been fully described by Schwartz [22]. Optimization techniques consist of the following essential operations: 1. Selection of a suitable experimental design 2. Selection of variables (independent Xs and dependent Ys) to be tested 3. Performance of a set of statistically designed experiments (e.g., 23 or 32 factorials) 4. Measurement of responses (dependent variables) 5. Development of a predictor, polynomial equation based on statistical and regression analysis of the generated experimental data 6. Development of a set of optimized requirements for the formula based on mathematical and graphical analysis of the data generated


XII. WHAT ARE THE PROCESS VALIDATION OPTIONS? The guidelines on general principles of process validation [1] mention three options: (1) prospective process validation (also called premarket validation), (2) retrospective process validation, and (3) revalidation. In actuality there are four possible options. A. Prospective Process Validation In prospective process validation, an experimental plan called the validation protocol is executed (following completion of the qualification trials) before the process is put into commercial use. Most validation efforts require some degree of prospective experimentation to generate validation support data. This particular type of process validation is normally carried out in connection with the introduction of new drug products and their manufacturing processes. The formalized process validation program should never be undertaken unless and until the following operations and procedures have been completed satisfactorily: 1. The facilities and equipment in which the process validation is to be conducted meet CGMP requirements (completion of installation qualification) 2. The operators and supervising personnel who will be running the validation batch(es) have an understanding of the process and its requirements 3. The design, selection, and optimization of the formula have been completed 4. The qualification trials using (10 size) pilot-laboratory batches have been completed, in which the critical processing steps and process variables have been identified, and the provisional operational control limits for each critical test parameter have been provided 5. Detailed technical information on the product and the manufacturing process have been provided, including documented evidence of product stability 6. Finally, at least one qualification trial of a pilot-production (100 size) batch has been made and shows, upon scale-up, that there were no significant deviations from the expected performance of the process The steps and sequence of events required to carry out a process validation assignment are outlined in Table 8. The objective of prospective validation is to prove or demonstrate that the process will work in accordance with a validation master plan or protocol prepared for pilot-product (100 size) trials. In practice, usually two or three pilot-production (100 ) batches are prepared for validation purposes. The first batch to be included in the sequence


Table 8 Master Plan or Outline of a Process Validation ProgramObjective Type of validation Type of process Definition of process Definition of process output Definition of test methods Analysis of process Control limits of critical variables Preparation of validation protocol Organizing for validation Planning validation trials Validation trials Validation finding Final report and recommendations Proving or demonstrating that the process works Prospective, concurrent, retrospective, revalidation Chemical, pharmaceutical, automation, cleaning Flow diagram, equipment/components, in-process, finished product Potency, yield, physical parameters Method, instrumentation, calibration, traceability, precision, accuracy Critical modules and variables defined by process capability design and testing program Defined by process capability design and testing program Facilities, equipment, process, number of validation trials, sampling frequency, size, type, tests to perform, methods used, criteria for success Responsibility and authority Timetable and PERT charting, material availability, and disposal Supervision, administration, documentation Data summary, analysis, and conclusions Process validated, further trials, more process design, and testing

may be the already successfully concluded first pilot batch at 100 size, which is usually prepared under the direction of the organizational function directly responsible for pilot scale-up activities. Later, replicate batch manufacture may be performed by the pharmaceutical production function. The strategy selected for process validation should be simple and straightforward. The following factors are presented for the readers consideration: 1. The use of different lots of components should be included, i.e., APIs and major excipients. 2. Batches should be run in succession and on different days and shifts (the latter condition, if appropriate). 3. Batches should be manufactured in equipment and facilities designated for eventual commercial production. 4. Critical process variables should be set within their operating ranges and should not exceed their upper and lower control limits during process operation. Output responses should be well within finished product specifications.


5. Failure to meet the requirements of the validation protocol with respect to process inputs and output control should be subjected to requalification following a thorough analysis of process data and formal review by the CMC Coordination Committee.

B. Retrospective Validation The retrospective validation option is chosen for established products whose manufacturing processes are considered stable and when on the basis of economic considerations alone and resource limitations, prospective validation programs cannot be justified. Prior to undertaking retrospective validation, wherein the numerical in-process and/or end-product test data of historic production batches are subjected to statistical analysis, the equipment, facilities and subsystems used in connection with the manufacturing process must be qualified in conformance with CGMP requirements. The basis for retrospective validation is stated in 21CFR 211.110(b): Valid in-process specifications for such characteristics shall be consistent with drug product final specifications and shall be derived from previous acceptable process average and process variability estimates where possible and determined by the application of suitable statistical procedures where appropriate. The concept of using accumulated final product as well as in-process numerical test data and batch records to provide documented evidence of product/ process validation was originally advanced by Meyers [26] and Simms [27] of Eli Lilly and Company in 1980. The concept is also recognized in the FDAs Guidelines on General Principles of Process Validation [1]. Using either data-based computer systems [28,29] or manual methods, retrospective validation may be conducted in the following manner: 1. Gather the numerical data from the completed batch record and include assay values, end-product test results, and in-process data. 2. Organize these data in a chronological sequence according to batch manufacturing data, using a spreadsheet format. 3. Include data from at least the last 2030 manufactured batches for analysis. If the number of batches is less than 20, then include all manufactured batches and commit to obtain the required number for analysis. 4. Trim the data by eliminating test results from noncritical processing steps and delete all gratuitous numerical information. 5. Subject the resultant data to statistical analysis and evaluation. 6. Draw conclusions as to the state of control of the manufacturing process based on the analysis of retrospective validation data. 7. Issue a report of your findings (documented evidence).


One or more of the following output values (measured responses), which have been shown to be critical in terms of the specific manufacturing process being evaluated, are usually selected for statistical analysis. 1. Solid Dosage Forms Individual assay results from content uniformity testing Individual tablet hardness values Individual tablet thickness values Tablet or capsule weight variation Individual tablet or capsule dissolution time (usually at t50%) or disintegration time 6. Individual tablet or capsule moisture content 2. Semisolid and Liquid Dosage Forms 1. 2. 3. 4. 5. 6. pH value (aqueous system) Viscosity Density Color or clarity values Average particle size or distribution Unit weight variation and/or potency values 1. 2. 3. 4. 5.

The statistical methods that may be employed to analyze numerical output data from the manufacturing process are listed as follows: 1 2. 3. 4. 5. 6. Basic statistics (mean, standard deviation, and tolerance limits) [21] Analysis of variance (ANOVA and related techniques) [21] Regression analysis [22] Cumulative sum analysis (CUSUM) [23] Cumulative difference analysis [23] Control charting (averages and range) [24,25]

Control charting, with the exception of basic statistical analysis, is probably the most useful statistical technique to analyze retrospective and concurrent process data. Control charting forms the basis of modern statistical process control. C. Concurrent Validation In-process monitoring of critical processing steps and end-product testing of current production can provide documented evidence to show that the manufacturing process is in a state of control. Such validation documentation can be provided from the test parameter and data sources disclosed in the section on retrospective validation.


Test parameterAverage unit potency Content uniformity Dissolution time Weight variation Powder-blend uniformity Moisture content Particle or granule size distribution Weight variation Tablet hardness pH value Color or clarity Viscosity or density

Data sourceEnd-product testing End-product testing End-product testing End-product testing In-process testing In-process testing In-process testing In-process testing In-process testing In-process testing In-process testing In-process testing

Not all of the in-process tests enumerated above are required to demonstrate that the process is in a state of control. Selections of test parameters should be made on the basis of the critical processing variables to be evaluated. D. Revalidation Conditions requiring revalidation study and documentation are listed as follows: 1. Change in a critical component (usually refers to raw materials) 2. Change or replacement in a critical piece of modular (capital) equipment 3. Change in a facility and/or plant (usually location or site) 4. Significant (usually order of magnitude) increase or decrease in batch size 5. Sequential batches that fail to meet product and process specifications In some situations performance requalification studies may be required prior to undertaking specific revalidation assignments. The FDA process validation guidelines [1] refer to a quality assurance system in place that requires revalidation whenever there are changes in packaging (assumed to be the primary container-closure system), formulation, equipment or processes (meaning not clear) which could impact on product effectiveness or product characteristics and whenever there are changes in product characteristics. Approved packaging is normally selected after completing package performance qualification testing as well as product compatibility and stability studies. Since in most cases (exceptions: transdermal delivery systems, diagnostic tests, and medical devices) packaging is not intimately involved in the manufacturing process of the product itself, it differs from other factors, such as raw materials.


The reader should realize that there is no one way to establish proof or evidence of process validation (i.e., a product and process in control). If the manufacturer is certain that its products and processes are under statistical control and in compliance with CGMP regulations, it should be a relatively simple matter to establish documented evidence of process validation through the use of prospective, concurrent, or retrospective pilot and/or product quality information and data. The choice of procedures and methods to be used to establish validation documentation is left with the manufacturer. This introduction was written to aid scientists and technicians in the pharmaceutical and allied industries in the selection of procedures and approaches that may be employed to achieve a successful outcome with respect to product performance and process validation. The authors of the following chapters explore the same topics from their own perspectives and experience. It is hoped that the reader will gain much from the diversity and richness of these varied approaches.

REFERENCES1. Guidelines on General Principles of Process Validation, Division of Manufacturing and Product Quality, CDER, FDA, Rockville, Maryland (May 1987). 2. Current Good Manufacturing Practices in Manufacture, Processing, Packing and Holding of Human and Veterinary Drugs, Federal Register 43(190), 45085 and 45086, September 1978. 3. Good Manufacturing Practices for Pharmaceuticals, Willig, S. H. and Stoker, J. R., Marcel Dekker, New York (1997). 4. Commentary, Pre-approval Inspections/Investigations, FDA, J. Parent. Sci. & Tech. 45:5663 (1991). 5. Mead, W. J., Process validation in cosmetic manufacture, Drug Cosmet. Ind., (September 1981). 6. Chapman, K. G., A history of validation in the United States, Part I, Pharm. Tech., (November 1991). 7. Nash, R. A., The essentials of pharmaceutical validation in Pharmaceutical Dosage Forms: Tablets, Vol. 3, 2nd ed., Lieberman, H. A., Lachman, L. and Schwartz, J. B., eds., Marcel Dekker, New York (1990). 8. Nash, R. A., Product formulation, CHEMTECH, (April 1976). 9. Pharmaceutical Process Validation, Berry, I. R. and Nash, R. A., eds., Marcel Dekker, New York (1993). 10. Nash, R. A., Making the Paper Match the Work, Pharmaceutical Formulation & Quality (Oct/Nov 2000). 11. Guidance for Industry, Scale-Up & Postapproval Changes, CDER, FDA (Nov 1995). 12. Bala, G., An integrated approach to process validation, Pharm. Eng. 14(3) (1994). 13. Farkas, D. F., Unit operations optimization operations, CHEMTECH, July 1977.


14. Nash, R. A., Streamlining Process Validation, Amer. Pharm. Outsourcing May 2001. 15. Ishikawa, K., What is Total Quality Control? The Japanese Way, Prentice-Hall, Englewood Cliffs, NJ (1985). 16. Nash, R. A., Practicality of Achieving Six Sigma or Zero-Defects in Pharmaceutical Systems, Pharmaceutical Formulation & Quality, Oct./Nov. 2001. 17. CGMP: Amendment of Certain Requirements, FDA Federal Register, May 3, 1996. 18. Box, G. E. and Hunter, J. S., Statistics for Experimenters, John Wiley, N.Y. (1978). 19. Hendrix, C. D., What every technologist should know about experimental design, CHEMTECH (March 1979). 20. Chapman, K. G., The PAR approach to process validation, Pharm. Tech., Dec. 1984. 21. Bolton, S., Pharmaceutical Statistics: Practical and Clinical Applications, 3rd ed., Marcel Dekker, New York (1997). 22. Schwartz, J. B., Optimization techniques in product formulation. J. Soc. Cosmet. Chem. 32:287301 (1981). 23. Butler, J. J., Statistical quality control, Chem. Eng. (Aug. 1983). 24. Deming, S. N., Quality by Design, CHEMTECH, (Sept. 1988). 25. Contino, AV., Improved plant performance with statistical process control, Chem. Eng. (July 1987). 26. Meyer, R. J., Validation of Products and Processes, PMA Seminar on Validation of Solid Dosage Form Processes, Atlanta, GA, May 1980. 27. Simms, L., Validation of Existing Products by Statistical Evaluation, Atlanta, GA, May 1980. 28. Agalloco, J. P., Practical considerations in retrospective validation, Pharm. Tech. (June 1983). 29. Kahan, J. S., Validating computer systems, MD&DI (March 1987).


1Regulatory Basis for Process ValidationJohn M. DietrickU.S. Food and Drug Administration, Rockville, Maryland, U.S.A.

Bernard T. LoftusU.S. Food and Drug Administration, Washington, D.C., U.S.A.

I. INTRODUCTION Bernard T. Loftus was director of drug manufacturing in the Food and Drug Administration (FDA) in the 1970s, when the concept of process validation was first applied to the pharmaceutical industry and became an important part of current good manufacturing practices (CGMPs). His comments on the development and implementation of these regulations and policies as presented in the first and second editions of this volume are summarized below [1].

II. WHAT IS PROCESS VALIDATION? The term process validation is not defined in the Food, Drug, and Cosmetic Act (FD&C) Act or in FDAs CGMP regulations. Many definitions have been offered that in general express the same ideathat a process will do what it purports to do, or that the process works and the proof is documented. A June 1978 FDA compliance program on drug process inspections [2] contained the following definition:

This chapter was written by John M. Dietrick in his private capacity. No official support or endorsement by the Food and Drug Administration is intended or should be inferred.


A validated manufacturing process is one which has been proved to do what it purports or is represented to do. The proof of validation is obtained through the collection and evaluation of data, preferably, beginning from the process development phase and continuing through the production phase. Validation necessarily includes process qualification (the qualification of materials, equipment, systems, buildings, personnel), but it also includes the control on the entire process for repeated batches or runs.

The first drafts of the May 1987 Guideline on General Principles of Process Validation [3] contained a similar definition, which has frequently been used in FDA speeches since 1978, and is still used today: A documented program which provides a high degree of assurance that a specific process will consistently produce a product meeting its pre-determined specifications and quality attributes. III. THE REGULATORY BASIS FOR PROCESS VALIDATION Once the concept of being able to predict process performance to meet user requirements evolved, FDA regulatory officials established that there was a legal basis for requiring process validation. The ultimate legal authority is Section 501(a)(2)(B) of the FD&C Act [4], which states that a drug is deemed to be adulterated if the methods used in, or the facilities or controls used for, its manufacture, processing, packing, or holding do not conform to or were not operated or administrated in conformity with CGMP. Assurance must be given that the drug would meet the requirements of the act as to safety and would have the identity and strength and meet the quality and purity characteristics that it purported or was represented to possess. That section of the act sets the premise for process validation requirements for both finished pharmaceuticals and active pharmaceutical ingredients, because active pharmaceutical ingredients are also deemed to be drugs under the act. The CGMP regulations for finished pharmaceuticals, 21 CFR 210 and 211, were promulgated to enforce the requirements of the act. Although these regulations do not include a definition for process validation, the requirement is implicit in the language of 21 CFR 211.100 [5], which states: There shall be written procedures for production and process control designed to assure that the drug products have the identity, strength, quality, and purity they purport or are represented to possess. IV. THE REGULATORY HISTORY OF PROCESS VALIDATION Although the emphasis on validation began in the late 1970s, the requirement has been around since at least the 1963 CGMP regulations for finished pharmaceuticals. The Kefauver-Harris Amendments to the FD&C Act were approvedCopyright 2003 Marcel Dekker, Inc.

in 1962 with Section 501(a)(2)(B) as an amendment. Prior to then, CGMP and process validation were not required by law. The FDA had the burden of proving that a drug was adulterated by collecting and analyzing samples. This was a significant regulatory burden and restricted the value of factory inspections of pharmaceutical manufacturers. It took injuries and deaths, mostly involving cross-contamination problems, to convince Congress and the FDA that a revision of the law was needed. The result was the KefauverHarris drug amendments, which provided the additional powerful regulatory tool that FDA required to deem a drug product adulterated if the manufacturing process was not acceptable. The first CGMP regulations, based largely on the Pharmaceutical Manufacturers Associations manufacturing control guidelines, were then published and became effective in 1963. This change allowed FDA to expect a preventative approach rather than a reactive approach to quality control. Section 505(d)(3) is also important in the implementation of process validation requirements because it gives the agency the authority to withhold approval of a new drug application if the methods used in, and the facilities and controls used for, the manufacture, processing, and packing of such drug are inadequate to preserve its identity, strength, quality, and purity. Another requirement of the same amendments was the requirement that FDA must inspect every drug manufacturing establishment at least once every 2 years [6]. At first, FDA did this with great diligence, but after the worst CGMP manufacturing situations had been dealt with and violations of the law became less obvious, FDA eased up its pharmaceutical plant inspection activities and turned its resources to more important problems. The Drug Product Quality Assurance Program of the 1960s and 1970s involved first conducting a massive sampling and testing program of finished batches of particularly important drugs in terms of clinical significance and dollar volume, then taking legal action against violative batches and inspecting the manufacturers until they were proven to be in compliance. This approach was not entirely satisfactory because samples are not necessarily representative of all batches. Finished product testing for sterility, for example, does not assure that the lot is sterile. Several incidents refocused FDAs attention to process inspections. The investigation of complaints of clinical failures of several products (including digoxin, digitoxin, prednisolone, and prednisone) by FDA found significant content uniformity problems that were the result of poorly controlled manufacturing processes. Also, two large-volume parenteral manufacturers experienced complaints despite quality control programs and negative sterility testing. Although the cause of the microbiological contamination was never proven, FDA inspections did find deficiencies in the manufacturing process and it became evident that there was no real proof that the products were sterile. What became evident in these cases was that FDA had not looked at the process itselfcertainly not the entire processin its regulatory activities; it was quality control- rather than quality assurance-oriented. The compliance offiCopyright 2003 Marcel Dekker, Inc.

cials were not thinking in terms of process validation. One of the first entries into process validation was a 1974 paper presented by Ted Byers, entitled Design for Quality [7]. The term validation was not used, but the paper described an increased attention to adequacy of processes for the production of pharmaceuticals. Another paperby Bernard Loftus before the Parenteral Drug Association in 1978 entitled Validation and Stability [8]discussed the legal basis for the requirement that processes be validated. The May 1987 Guideline on General Principles of Process Validation [3] was written for the pharmaceutical, device, and veterinary medicine industries. It has been effective in standardizing the approach by the different parts of the agency and in communicating that approach to manufacturers in each industry.

V. UPDATE As discussed in the preceding sections, process validation has been a legal requirement since at least 1963. Implementation of the requirement was a slow and deliberate process, beginning with the development and dissemination of an agency policy by Loftus, Byers, and others, and leading to the May 1987 guideline. The guideline quickly became an important source of information to pharmaceutical manufacturers interested in establishing a process validation program. Many industry organizations and officials promoted the requirements as well as the benefits of validation. Many publications, such as Pharmaceutical Process Validation [1] and various pharmaceutical industry journal articles, cited and often expanded on the principals in the guideline. During the same period, computer validationor validation of computer controlled processes also became a widely discussed topic in both seminars and industry publications. The regulatory implementation of the validation requirement was also a deliberate process by FDA. During the 1980s, FDA investigators often reported processes that had not been validated or had been inadequately validated. Batch failures were often associated with unvalidated manufacturing processes. The FDA issued a number of regulatory letters to deficient manufacturers citing the lack of adequate process validation as a deviation from CGMP regulations (21CFR 211.100), which causes the drug product to be adulterated within the meaning of Section 501(a)(2)(B) of the federal FD&C Act. Process validation was seldom the only deficiency listed in these regulatory letters. The failure of some manufacturers to respond to these early warnings resulted in FDA filing several injunction cases that included this charge in the early 1990s. Most of these cases resulted in consent decrees, and ultimately the adoption of satisfactory process validation programs by the subject manufacturers. One injunction case filed in 1992, however, was contested in court and led to a lengthy written order and opinion by the U.S. District Court in February of 1993 [9]. The court


affirmed the requirement for process validation in the current good manufacturing regulations, and ordered the defendants to perform process validation studies on certain drug products, as well as equipment cleaning validation studies. This case and the courts ruling were widely circulated in the pharmaceutical industry and became the subject of numerous FDA and industry seminars. The court also criticized the CGMP regulations for their lack of specificity, along with their ambiguity and vagueness. Responding to this criticism, FDA drafted revisions to several parts of these regulations. The proposed revisions were published in the Federal Register on May 3, 1996 [10]. One of the main proposed changes was intended to emphasize and clarify the process validation requirements. The proposal included a definition of process validation (the same definition used in the 1987 guideline), a specific requirement to validate manufacturing processes, and minimum requirements for performing and documenting a validation study. These were all implied but not specific in the 1978 regulation. In proposing these changes, FDA stated that it was codifying current expectations and current industry practice and did not intend to add new validation requirements. Comments from all interested parties were requested under the agencys rule-making policies, and approximately 1500 comments were received. Most of the responses to the changes regarding process validation supported the agencys proposals, but there were many comments regarding the definitions and terminology proposed about which processes and steps in a process should or should not require validation, the number of batches required for process validation, maintenance of validation records, and the assignment of responsibility for final approval of a validation study and change control decisions. Because of other high-priority obligations, the agency has not yet completed the evaluation of these responses and has not been able to publish the final rule. In addition to the official comments, the proposed changes prompted numerous industry and FDA seminars on the subject. Process validation is not just an FDA or a U.S. requirement. Similar requirements are included in the World Health Organization (WHO), the Pharmaceutical Inspection Co-operation Scheme (PIC/S), and the European Union (EU) requirements, along with those of Australia, Canada, Japan, and other international authorities. Most pharmaceutical manufacturers now put substantial resources into process validation for both regulatory and economic reasons, but despite continued educational efforts by both the agency and the pharmaceutical industry, FDA inspections (both domestically and internationally) continue to find some firms manufacturing drug products using unvalidated or inadequately validated processes. Evidently there is still room for improvement, and continued discussion, education, and occasional regulatory action appears warranted. The future of process validation is also of great interest, especially with the worldwide expansion of pharmaceutical manufacturing and the desire for


harmonized international standards and requirements. Many manufacturers are also working on strategies to reduce the cost of process validation and incorporate validation consideration during product design and development. New technologies under development for 100% analysis of drug products and other innovations in the pharmaceutical industry may also have a significant effect on process validation concepts and how they can be implemented and regulated.

REFERENCES1. Loftus, B. T., Nash, R. A., ed. Pharmaceutical Process Validation. vol. 57. New York: Marcel Dekker (1993). 2. U.S. Food and Drug Administration. Compliance Program no. 7356.002. 3. U.S. Food and Drug Administration. Guideline on General Principles of Process Validation. Rockville, MD: FDA, 1987. 4. Federal Food Drug and Cosmetic Act, Title 21 U.S. Code, Section 501 (a)(2)(B). 5. Code of Federal Regulations, Title 21, Parts 210 & 211. Fed Reg 43, 1978. 6. U.S. Code, Federal Food Drug and Cosmetic Act, Title 21, Section 510 (h). 7. Byers, T. E. Design for quality, Manufacturing Controls Seminar, Proprietary Association, Cherry Hill, NJ, Oct. 11, 1974. 8. Loftus, B. T. Validation and stability, meeting of Parenteral Drug Association, 1978. 9. U.S. v. Barr Laboratories, Inc., et al., Civil Action No. 92-1744, U.S. District Court for the District of New Jersey, 1973. 10. Code of Federal Regulations, Title 21, Parts 21 & 211, Proposed Revisions, Fed Reg (May 3, 1996).


2Prospective Process ValidationAllen Y. ChaoWatson Labs, Carona, California, U.S.A.

F. St. John ForbesWyeth Labs, Pearl River, New York, U.S.A.

Reginald F. Johnson and Paul Von DoehrenSearle & Co., Inc., Skokie, Illinois, U.S.A.

I. INTRODUCTION Validation is an essential procedure that demonstrates that a manufacturing process operating under defined standard conditions is capable of consistently producing a product that meets the established product specifications. In its proposed guidelines, the U.S. Food and Drug Administration (FDA) has offered the following definition for process validation [1]. Process validation is establishing documented evidence that provides a high degree of assurance that a specific process (such as the manufacture of pharmaceutical dosage forms) will consistently produce a product meeting its predetermined specifications and quality characteristics. Many individuals tend to think of validation as a stand-alone item or an afterthought at the end of the entire product/process development sequence. Some believe that the process can be considered validated if the first two or three batches of product satisfy specifications. Prospective validation is a requirement (Part 211), and therefore it makes validation an integral part of a carefully planned, logical product/process developmental program. An outline of the development sequence and requirements relevant to process validation is presented in Figure 1. After briefly discussing organizational aspects and documentation, the integration of validation into the product development sequence is discussed. At the end of the chapter there is a


brief discussion of specific ways in which experimental programs can be defined to ensure that critical process development and validation objectives are met.

II. ORGANIZATION Prospective validation requires a planned program and organization to carry it to successful completion. The organization must have clearly defined areas of responsibility and authority for each of the groups involved in the program so that the objective of validating the process can be met. The structure must be tailored to meet the requirements in the specific organization, and these will vary from company to company. The important point is that a defined structure exists, is accepted, and is in operation. An effective project management structure will have to be established in order to plan, execute, and control the program. Without clearly defined responsibilities and authority, the outcome of process validation efforts may not be adequate and may not comply with CGMP requirements.

III. MASTER DOCUMENTATION An effective prospective validation program must be supported by documentation extending from product initiation to full-scal

Pharmaceutical Process Validation NASH

Documents