Efficient Risk Based Regulatory Scrutiny for Assuring Pharmaceutical Quality in the 21st Century
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Efficient Risk Based Regulatory Scrutiny for Assuring Pharmaceutical Quality in the 21st Century Ajaz Hussain, Ph.D. and David Horowitz, Esq. CDER, FDA Arden House 2004, London Outline Challenging opportunities for improving efficiency and effectiveness Science, Risk, Quality Systems, Harmonization Risk based CMC & Biopharm Review What type of “knowledge” may be most useful Risk based GMP Inspections Part I: What type of “knowledge” may be most useful for risk based CMC Review Evolution of Product Development Data base -to- Knowledge base Empirical models Mechanistic models Regulatory utility Efficient and Effective Design Product quality and performance achieved and assured by design Dosage form Manufacturing process, ... Specifications based on mechanistic understanding of how formulation and process factors impact product performance Continuous "real time" assurance of quality Highest (pragmatic) level of process understanding Mitigate Risk Risk of incorrect identity Poor product & process Changes in clinical trial product Inadequate Design Specifications Critical to quality and performance? Risk of unqualified impurities Risk of poor bioavailability Risk of incorrect expiry date Risk of inadequate controls Risk of SUPAC,.. Risk of unrepresentative test samples] Risk of Inadequate Facility and QS Tests & Controls -Risk Mitigation Design for Intended Use: Focus on Reliability Intended Use Route of administration Patient population ….. Product Design Design Specifications (Customer requirements) Regulatory Specs. Manufacturing Process and its Control Efficient Design: Different Strategies Design strategies are generally company dependent Regulatory process should only focus on the outcome of these efforts Certain information and knowledge utilized during design justification and development can be useful for science based regulatory decisions Regulatory Utility of Development Knowledge Structured knowledge that provides a means for evaluating and predicting product performance Can be for certain aspects or be broad to cover all aspects Fragmented/incomplete not be useful bits of data may Need a general understanding and criteria for the type of knowledge useful for regulatory utility Elements of Decision Making in PD Long-term memory Data - Information (communication)Knowledge -relationship in Product Development Significant reliance on personal knowledge as information source in PD Generation of memory and experience is achieved over a long period of time Court A W. Int. J. Info. Management.. 17: 123, 1997 Short-term memory Pharmaceutical Product Development Multi-factorial complex problem Significant reliance on personal knowledge Historical data likely to have been generated by a “Trialn-Error” approach Many choices for achieving target specifications Without up-to-date information, high potential for: misjudgments “reinventing the wheel” Mobile “institutional memory” Approved product needs frequent changes .. Evolution of Product Development Process “Art” Science & Engineering based Trial-and-Error DOE CAD Few creative options tested Many creative options tested Dosage forms Drug Delivery Intelligent Drug Delivery CMC Review : Increased Reliance on Pharmaceutics to optimize regulatory tests & filing req. Product Development Knowledge Level of Sophistication HIGH Details Resolved Rules HIGH MECHANISTIC MODELS MEDIUM LOW EMPIRICAL MODELS HEURISTIC RULES “Rules of Thumb” HISTORICAL DATA DERIVED FROM TRIAL-N-ERROR EXPERIMENTATION MEDIUM LOW Artificial Intelligence (AI) and Information Technology (IT) can Improve the Utility of Historical Data Expert Systems (AI) Rules MECHANISTIC MODELS Fuzzy ES EMPIRICAL MODELS HEURISTIC RULES “Rules of Thumb” HISTORICAL DATA DERIVED FROM TRIAL-N-ERROR EXPERIMENTATION ANN (IT) Hypothesis (Hussain,1989): “ANN Based Computer Aided Formulation Design” Many Challenges Very complex systems Subjective descriptions of excipient “functionality” Historic process controls that do not necessarily control critical attributes of inprocess materials Subjective equipment similarity descriptions Initial focus on Comparison to RSM Tool for improving technical and marketing support functions of an excipient supplier: Klucel Net (Aqualon) Formulation and marketing tool for a propriety formulation technology: TIMERx ANN Structure and Function Data/Information Ability to predict outcome (Knowledge) OUTPUT INPUT Simulation tool; “What-If” analysis Pattern visualization tool, Optimization, etc. Feasibility of Predicting Drug Dissolution From Multisource Tablet Formulations V.K. Tammara,1 A.S. Carlin,2 M.U. Mehta1 and A.S. Hussain 2 1 Division of Pharmaceutical Evaluation I, Office of Clinical Pharmacology and Biopharmaceutics and 2 Division of Product Quality Research, Office of Testing and Research, CDER, FDA AAPS Annual Meeting 1999 Proposed SUPAC-IR Network Phase III Phase I Phase II In Vitro Dissolution Drug attributes and dissolution test conditions Composition Equipment (D/OP) and Process Methods • Similarity between training (FDA/UMAB) and test (ANDA) formulations FDA/UMAB 1 2 3 4 5 6 7 8 9 Binder X X Diluent A X X Disint. Diluent B X Lubricant X Granulation X method Test Formulation 9 ANDA 1 Prediction Error %: Q(10) -29 Prediction Error %: Q(30) -15 ANDA 2 -2 -2 ANDA 3 13 13 ANDA 4 - 6 - 4 ANDA 5 25 4 ANDA 6 7 2 ANDA 7 14 -5 ANDA 8 - 4 4 ANDA 9 - 14 7 Innovator 6 -7 Results and Discussion Component Diluent A (IN) Diluent A (OUT) Diluent B Disintegrant (IN) Disintegrant (Out) Binder Lubricant SUPAC Reco. Limit (Level 2) 10% 10% 10% 2% 2% Max change in component having no impact on dissolution (15% or less difference in dissolution) 15% 30% 70% 7% 3% 1% 0.5% 5% 2% Specifications Product specifications based on mechanistic understanding of how formulation and process factors impact product performance Continuous "real time" assurance of quality Empirical Models: Experimental Designs (e.g., Mixture Designs) Set of combinations of the proportions (or blends) used to collect observed response values range of interest of the formulator (entire simplex surface or partial surface) Properties of the polynomials used to estimate the response function depend on the experimental design Factor Space x1 =1 (1,0,0,0) x1 =1 x1=x2=0.5 x2 =1 x1 =1 (1,0,0) x4 =1 (0,0,0,1) x3 =1 (0,0,1,0) x2 =1 (0,1,0,0) x2 =1 (0,1,0) x3 =1 (0,0,1) Response Surface Choice of model to approximate the surface over the “region of interest” Testing for adequacy of the model Suitable experimental design Assumption - existence of a continuous functional relationship ( x1 , x2 ,....., x q ) Sathyan, G., Ritschel, W. A. and Hussain, A. S.: Transdermal delivery of tacrine, I: Identification of a suitable delivery vehicle. Int. J. Pharm. 114: 75-83 (1995). In Vitro Flux (Human Skin) Permeability (Human Skin) 0.0 1.0 0.0 1.0 P 0.5 0.5 E 0.5 E P 36 42 48 30 0.5 8 24 5 18 4 12 0.0 1.0 1.0 0.0 0.0 1.0 16 19 22 0.5 E 25 0.5 28 31 1.0 0.0 0.5 W 3 0.5 W Lag-Time (Human Skin) P 0.5 W 2 6 1.0 0.0 7 6 0.0 1.0 0.0 1.0 Drug-Polymer and Polymer #1Polymer #2 Ratios Effect on drug release mechanism form a hydrophilic matrix capsule containing HEC + Na.CMC Drug + HEC + Na.CMC =1 Variables: M Response: n, T50% M k t Design: Factorial Drug HEC Na.CMC HEC Na.CMC t n Hussain, A. S., Johnson, R. D., Shivanand, P. and Zoglio, M. A.: Effects of blending a nonionic and an anionic cellulose ether polymer on drug release from hydrophilic matrix capsules. Drug. Dev. Ind. Pharm. 20: 2645-2657 (1994). Optimal Formulations Composition Formulation 1 Formulation 2 HEC 0.35 0.43 Na. CMC 0.46 0.44 Drug 0.19 0.13 Response Calc. Obs. Calc. Obs. n 1 1 (0.13) 1 1(0.08) T50% 7.5 7.8(0.73) 8 8.1(0.8) Region of Interest (Mixture+Process) X1=1 Z=+1 w2 w1 X2=1 X3=1 Z=-1 w2 w1 X2=1 X3=1 A move towards “Mechanism” (macro-scale) The following slides provide a brief summary of current research on topical microbicide vaginal products is an example of the “mechanistic” approach • linking physics with physiology to identify critical product attributes and explain how these attributes effect product performance Desired Distribution Profile of Certain Vaginal Formulations VAGINA CERVIX MUCUS INTROITUS PROPHYLACTIC COATING CONTRACEPTIVE COATING Interactions in the Vagina Fluid Contents Anatomy, Geometry Microbicide Formulation Surface Properties Mechanical Properties Pre-Coital Forces Acting on a Bolus of Gel in Vagina “SQUEEZING” visceral contractions pressure tissue elasticity rugae “SEEPING” surface energies interfacial tensions “SLIDING” gravity David Katz. Duke University Mechanistic Analysis of Subprocesses (Squeezing) • THEORY • SIMULATION vehicle epithelial surfaces F R FORMULATION 2h Area(t)= David Katz. Duke University Solution for elastic surfaces (E, n); lubrication approximation; power law fluid (n, m); conserved bolus volume V = 2hoπ R2 SLIDING THEORY Vavg velocity profile velocity depends upon… vagina properties tilt angle a tissue separation Htot gel properties density rheology Htot a David Katz. Duke University David Katz. Duke University Axial and Angular Dependence of Coating Thickness Distribution Conceptrol Advantage Axial Dependence Thickness (m m) Thickness (m m) Axial Dependence 1000 Scaled to length of 71.11 mm 500 0 0 0.5 1000 500 315 270 500 0 225 135 180 % Volume Distal to Fornix 1 Angular Dependence Thickness in microns 85% 45 90 0.5 Axial Length 39% 0 1000 0 0 1 Axial Length Angular Dependence Thickness in microns Scaled to length of 51.67 mm 0 1000 315 % of Area Coated 36% 100% 270 500 0 225 45 90 135 180 http://www.fda.gov/cder/gmp/21stcenturysummary.htm Desired State Regulatory policies tailored to recognize the level of scientific knowledge supporting product applications, process validation, and process capability Risk based regulatory scrutiny relate to the: level of scientific understanding of how formulation and manufacturing process factors affect product quality and performance, and the capability of process control strategies to prevent or mitigate risk of producing a poor quality product Quality Risk Scenarios Risk of unacceptable quality (examples) Releasing a unacceptable quality product • Inadequate controls/specifications “New” impurities or degradation products Bio-in-equivalence • Inadequate process validation Process not understood, sampling not “representative” Stability failure Unacceptable S&E profile, Bio-in-equivalence Poor Process quality Others AAPS Poster, November 2001 STABILITY PROFILES OF DRUG PRODUCTS EXTENDED BEYOND LABELED EXPIRATION DATES Jeb S. Taylor1, Robbe C. Lyon1, Hullahalli R. Prasanna1, Ajaz S. Hussain2 Center for Drug Evaluation and Research, FDA, 1Division of Product Quality Research, Nicholson Research Center, Kensington, MD; 2Office of Pharmaceutical Sciences, Rockville, MD INTRODUCTION The FDA administers the Shelf Life Extension Program for the U.S. Military. Selected drug products are tested to determine if their shelf life can be extended past labeled expiration date. Program probably contains the most extensive source of stability data available. The test attributes, methods of evaluation and analysis are described. This report summarizes extended stability profiles for 96 different drug products. SUMMARY Results from 1122 lots (96 drug products) were evaluated. 84% of the lots were extended for an average of 57 months past the original expiration date. Of the 946 lots extended, 14% were eventually terminated due to failure. The rest are still active or discontinued by the military. 22 Drug Products showed no signs of stability failure (at least 5 lots of each tested). 10 Drug Products were unstable with most lots failing initial extension. Group 6: Unstable Products: Most* Lots Fail Initial Extension Drug Product Albuterol Brompheniramine Maleate Phenylpropanolamine HCl Diphenhydramine HCl Isoproterenol HCl Levarterenol Bitartrate Lidocaine HCl & Epinephrine Mefloquine HCl Penicillin G Procaine Phenobarbital Sodium Inj Physostigmine Salicylate * 50% Occurrence Dosage Form Aerosol SR Tablets # of Lots # of Lots Initial Extension Tested Extended Failures 2 0 Assay: Stress (2) 4 0 Appearance: Stress (4) Spray Injection 2 8 0 2 Injection Injection 9 7 2 0 Tablets Powder Cartridge-Needle Injection 19 5 3 14 4 1 1 4 Assay (2) Assay (4) Assay: Stress (2) Assay: Stress (7) Assay (2) Assay : Stress (5) Dissolution (15) Assay (4) Assay (2) Low pH (10) CONCLUSIONS Actual Shelf Life may be much longer than indicated by Expiration Date on the label. Stability Period is highly variable from lot to lot. Continued testing and systematic evaluation is required to provide assurance that stability and product quality is maintained. YES Dissolution generally “overdiscriminating” Why? Dissolution fails to signal bio-in-equi ~ 30% (?) NO Bioequivalent Dissolution Test & Bioequivalence: Risk Assessment NO YES Dissolution Specification Appropriate Specification or “Overdiscrimination” All Bioequivalent to RLD DISSOLUTION OF GENERIC & RESEARCH TABLETS 110 100 90 ANDA1 ANDA2 80 ANDA3 ANDA4 70 ANDA5 60 ANDA6 ANDA7 50 ANDA8 40 ANDA8 74-217 30 UMAB-SLOW UMAB-MEDIUM 20 UMAB-FAST 10 0 0 5 10 15 20 TIME IN MINUTES 25 30 35 % Drug Dissolved Failure to Discriminate Between Bio-inequivalent Products: Inappropriate Acceptance Criteria Product B 110 100 90 80 70 60 50 40 30 20 10 0 Product B was not bioequivalent to Product A Product A Log(AUCinf): CI 94.6 - 123.6 USP Specification 0 10 20 30 Time in Minutes Log(AUC): CI 89.1 - 130.0 40 50 Cmax: CI 105.3 - 164.2 Failure to Discriminate Between Bio-inequivalent Products: Inappropriate Test Method? (weak acid, rapid dissolution in SIF) Capsule (Ref.) 1800 1600 Tablet 1 (wet-granulation - starch) Drug Concentration in Plasma (ng/ml) 1400 1200 Tablet 2 (direct compression calcium phosphate) 1000 800 600 400 200 USP Paddle 50rpm, Q 70% in 30 min 0 0 1 2 3 Time in Hours 4 5 6 False Positives and False Negatives!!! Test/Ref. Mean 15 min 30 min 45 min AUC Cmax Ref 95 96 98 100 100 B 96 97 97 104 95 C 62 84 92 84 55 D 82 94 95 88 87 E 103 103 103 112 120 F 13 35 53 100 102 I. J. MacGilvery. Bioequivalence: A Canadian Regulatory Perspective. In, Pharmaceutical Bioequivalence . Eds. Welling, Tse, and Dighe. Marcel Dekker, Inc., New York, (1992)). Failure of Dissolution Tests to Signal Bio-in-equivalence Inappropriate “acceptance criteria” Inappropriate test method One point specification Set “too late” media composition (pH,..) media volume hydrodynamics Excipients affect drug absorption Dissolution is NOT “RATE LIMITING” Other reasons (many critical test variables) Is Dissolution Rate Limiting? Concentration 3.5 Capsule Solution 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0 4 8 12 Time 16 20 24 ICH Q6A DECISION TREES #7: SETTING ACCEPTANCE CRITERIA FOR DRUG PRODUCT DISSOLUTION What specific test conditions and acceptance criteria are appropriate? [IR] What? YES dissolution significantly affect BA? Develop test conditions and acceptance distinguish batches with unacceptable BA NO Do changes in formulation or manufacturing variables affect dissolution? Why? Are these changes controlled by another procedure and acceptance criterion? YES YES NO NO Adopt appropriate test conditions and acceptance criteria without regard to discriminating power, to pass clinically acceptable batches. Adopt test conditions and acceptance criteria which can distinguish these changes. Generally, single point acceptance criteria are acceptable. aaps Annual Meeting How? 49 ICH Q6A: Decision Tree #7 (1) Modified release? Yes No Establish drug release acceptance criteria: ER: Multiple time point MR: Two stage, parallel or sequential High solubility? Yes Rapid dissolution? ? Yes Relationship between Disintegration - Dissolution? No No Generally single-point dissolution acceptance criteria with a lower limit No Yes Generally disintegration acceptance criteria with an upper limit Disintegration - Dissolution Relationship Disintegration Time (DT) Disintegration Fraction dissolved Ft Fl Tablet Surface (t) 10# screen Fs Large Fragments (l) Fs* Small Fragments (s) Total Dissolution = Ft + Fl + Fs + Fs* Prior to DT After DT Note: Disintegration and dissolution process in a dissolution apparatus may differ from that in a disintegration apparatus (different hydrodynamics and other conditions) Data Dissolution and disintegration time data and the impact of formulation variables on dissolution at various time points (Figure 1) C u m u la tiv e D is s o lu tio n a n d D is in te g r a tio n D a ta : C r itic a l F o r m u la tio n V a r ia b le s 120 M C C (-) S S G (+ ) [M g S (-)] D r u g D is s o lv e d 100 M C C (-) S S G (+ ) M g S (-) 80 60 % 40 20 0 C o r r e s p o n d in g D is in te g r a tio n T im e D a ta 0 5 10 15 20 T im e in M in u te s Li et al, Pharm. Develop. And Tech. 1: 343-355, 1996 and Rekhi et al., Pharm. Develop. and Tech. 2: 11-24, 1997 25 30 35 Predicting Dissolution of Experimental Furosemide Tablets Using Near Infrared Spectroscopy Everett H. Jefferson1, Alan S. Carlin1, Robbe C. Lyon1, Lawrence X. Yu2, Robert L. Hunt1, Jin T. Wang1, William N. Worsley1, Ajaz S. Hussain3 1Division of Product Quality Research, FDA, Kensington, MD 2Office 3Office of Generic Drugs, FDA, Rockville, MD of Pharmaceutical Science, FDA, Rockville, MD Predicting Product Dissolution Develop Casual Links based on Critical Attributes Formulation-Processing Casual Link NIR Spectra Non-destructive Test Casual Link Correlation Dissolution (opportunity to consider direct link to PK/PD) Destructive Test Dissolution - Formulation: Casual Link Dissolution is a function of processing variables: Dissolution = f (Ex1, Ex2, P1, P2, PS…) Ex1, Ex2 = Excipients (USP/NF) P1, P2 = Process parameters (time, hardness ...) PS = Drug particle size (specification) Use Multiple Linear Regression (MLR) to determine the variables critical to dissolution: y = 0 + 1 x1 + 2 x2 + 3 x3 + 12 x1 x2 + 13 x1 x3 + 23 x2 x3 + ... Dissolution-Formulation Correlation: Direct Compression (%Diss at 15 min) Regression Model: %Diss_15 = 56.3 + 25.3 x2 - 15.1 x1 x2 Filler AcDiSol MgS Hardness Filler*AcDiSol Filler*MgS Filler* Hardness AcDiSol*MgS AcDiSol*Hardness MgS*Hardness x2 x1 x2 The critical formulation variables (p<0.05): disintegrant level disintegrant and filler interaction Within the design space only - e.g.,other variables held constant NIR - Dissolution Correlation: Direct Compression (%Diss at 15 min) Predicted % Dissolution 100 Direct Compression (Lots 121-132) PLS1 Model 2nd Derivative Spectra 80 60 Training Set (n=72) R2 = 0.9771 40 Test Set (n=72) R2 = 0.9465 20 0 0 20 40 60 Measured % Dissolution 80 100 NIR - Formulation: Casual Link NIR Spectra of the Raw Materials 2.0000 3.0000 Furosemide Avicel Magnesium Stearate 2.5000 2.0000 1.5000 Intensity Intensity 1.5000 1.0000 0.5000 1.0000 0.5000 0.0000 0.0000 -0.5000 -0.5000 -1.0000 -1.0000 -1.5000 1100 1300 1500 1700 1900 Wavelength 2100 2300 2500 Lactose Monohydrate Ac-Di-Sol Starch Povidone -1.5000 1100 1300 1500 1700 1900 2100 2300 2500 Wavelength NIR - Formulation Correlations Lactose 250 200 Direct Com pression PLS1 Model 2nd Derivative Spectra 200 Training Set (n=72) 2 R = 0.9790 150 Avicel 250 Direct Com pression PLS1 Model 2nd Derivative Spectra Predicted Avicel (mg) 2.5000 Predicted Lactose (mg) 3.0000 100 Test Set (n=72) 2 R = 0.9786 50 0 Training Set (n=72) 2 R = 0.9741 150 100 Test Set (n=72) 2 R = 0.9742 50 0 0 50 100 150 200 250 -50 0 50 100 150 -50 Measured Lactose (mg) Manufacturing Constituent Process Ac-Di-Sol Direct Compression Mg Stearate Direct Compression Starch W et Granulation Povidone W et Granulation Measured Avicel (mg) Training Set R2 n 72 0.9897 72 0.9780 48 0.9758 24 0.9911 Test n 72 72 48 24 Set R2 0.9860 0.9781 0.9539 0.9873 200 250 Process Understanding CMC regulatory oversight cGMP regulatory oversight Company’s Quality system Post approval change Risk (P/R) Process Understanding CMC regulatory oversight Process Understanding CMC regulatory oversight cGMP regulatory oversight cGMP regulatory oversight Company’s Quality system Company’s Quality system Post approval change Risk Post approval change Risk CMC-GMP Risk Model Should allow us to recognize the level of process understanding for a given product Provide a means to move towards a one time CMC review process for well understood products and processes (current system will remain for others) Exception - unless specifications need to change Continuous improvement within a companies quality system Share and have available knowledge throughout the organization Risk Mitigation Opportunities • Advances in application of risk analysis and risk management (including IT revolution) • More systematically applied outside pharmaceutical sector Including data generated by advanced manufacturing technologies • Risk management approaches to regulatory compliance gaining wider acceptance among regulators Risk to Quality “Risk” to pharmaceutical quality is associated with factors that relate to the probability or severity of adverse effects on these attributes Factors associated with compromising : • e.g., identity, strength/potency, bioavailability, purity, or clear/accurate labeling Applying Risk Management to Drug Quality Regulation (cont’d) Tools and techniques for identifying and focusing on critical processes and parameters potentially include: Failure Modes and Effects Analysis (FMEA) Hazard Analysis and Critical Control Points (HACCP) Fault Tree Analysis (FTA) Hazard and Operability Study (HAZOP) Applying Risk Management to Drug Quality Regulation (cont’d) To support more focused regulatory scrutiny we need: Greater understanding of the sources of risk to product quality • Including factors predictive of that risk, as well as those that are predictive of the successful mitigation of the risk; and Enhanced hazard identification and risk assessment capacity Applying Risk Management to Drug Quality Regulation (cont’d) Greater uncertainly requires greater regulatory scrutiny Burden must rest largely with regulated industry to demonstrate to regulators that reduced regulatory scrutiny is justified by the science/data Regulators need to support industry efforts to develop and provide the needed science/data Applying Risk Management to Drug Quality Regulation (cont’d) Risks to pharmaceutical quality can be ranked by identifying and weighting factors associated with the probability or severity of adverse effects on quality attributes and surrogates What processes and parameters are critical for identity, strength/potency, bioavailability, purity, or clear/accurate labeling? What factors will adversely (or positively) affect critical parameters/processes, increasing probability or severity or impact? Risk Management and Resource Allocation FDA is developing a model using a Risk Ranking and Filtering technique to better focus inspectional resources based upon the risk of manufacturing deficiencies that would reduce drug quality systematically incorporate our current knowledge about drug quality risks and manufacturing sites Prioritize sites for periodic systems-based inspections Risk Management and Resource Allocation (cont’d) Starting in FY ‘03, shifted emphasis to facilities making drugs perceived to be of higher risk if subject to manufacturing deficiencies • Sterile drugs • Rx drugs (non-medical gas) • New registrants New model under development for pilot implementation later this year A RISK-BASED FRAMEWORK FOR PRIORITIZING SITES FOR cGMP INSPECTION SITE RISK POTENTIAL PRODUCT PROCESS Site potential risk score: [wp Product weight] x [wPr Process weight] x [wfx Facility weight]; “w” is the relative weight assign to the individual module Semi-quantitative weights high, medium, low; yes/no; ordinal scales 1- 5 FACILITY Risk Ranking Model: Product Factors What are the intrinsic properties of drug products such that deficiencies in quality, if any, would have more adverse public health impact than others? sterile Rx vs. OTC Route of administration Mining recall data can help weight product factors (e.g., product or dosage form associated with prevalence of serious recalls?) Risk Ranking Model: Facility Factors Are some manufacturing facilities (or manufacturers) more likely to produce a product with quality problems? Effectiveness of quality systems and process capability Inspectional record and compliance history • Exposure: volume produced at facility Product sales volume Special/sensitive populations • Other characteristics? New Registrants? Macher and Nickerson study will help identify Risk Ranking Model: Process Factors Are some manufacturing processes, for particular product classes, more likely to go wrong than others? Are some process problems of greater public health significance? What are the consequences of process problems? • Use expert elicitation to identify risk factors and weightings At the unit operation level By product classes • Risk of contamination or mix-ups • Maintaining state of control of the process Risk Management and Resource Allocation (cont’d) Risk ranking and filtering technique may be a useful tool for other aspects of drug quality regulation Focus compliance programs? Guidance development? Regulatory action decisions? Industry internal audits? Risk Management and Resource Allocation (cont’d) The product can only be as good as the scientific/technical input/assumptions that are used to develop the risk scores Multiple iterations and successive revisions will reflect growing knowledge base and extensive input from internal and external experts