Mar 24, 2015 - 41(2) Stimuli to the Revision Process: Modernization of Identification Tests ... Questions in the survey addressed demographics, use of chapter ...
41(2) Stimuli to the Revision Process: Modernization of Identification Tests in USP-NF
Page 1 of 7
STIMULI TO THE REVISION PROCESS Stimuli articles do not necessarily reflect the policies of the USPC or the USP Council of Experts
Modernization of Identification Tests in USP–NF Nancy Lewen,a Anthony C Bevilacqua,b Bernard A Olsen,b Anne Warner,b Michelle Adamson,b Geoffrey Carr,b Pei Chen,b Jonathan DeVries,b Maryna Dmitriieva,b Michael Hornig,b Jeffrey Rohrer,b Antonio Hernandez-Cardosoc,d ABSTRACT For consistency with the overall USP effort to modernize monographs and general chapters, Identification Tests—General 191 was identified for revision to address safety and environmental concerns, clarity and accuracy of the description of wet-chemistry tests, harmonization with other pharmacopeias, and provision of an option to use instrumental methods. This Stimuli article accompanies the proposed revision of general chapter 191 , also published in this issue of Pharmacopeial Forum, and describes the rationale and strategy used to revise the chapter. INTRODUCTION Identity is a critical quality attribute of a pharmaceutical, and identification tests are critical for any pharmacopeial monograph. In USP–NF, some procedures for identification testing are included in individual monographs, and two general chapters containing identification procedures are referenced frequently in monographs. General chapter Identification Tests— General 191 is applied for the identification of ions or counterions of drug salts. Infrared (IR) and ultraviolet (UV) spectrophotometric tests, described in general chapter Spectrophotometric Identification Tests 197 , are used frequently for identification of active ingredients or their salts. For consistency with the overall USP effort to modernize monographs and general chapters, chapter 191 was identified for revision to address safety and environmental concerns, clarity and accuracy of the description of wet-chemistry tests, harmonization with other pharmacopeias, and the option to use instrumental methods. Existing flame tests in chapter 191 will be replaced; affected monographs will show other complementary tests (e.g., wet-chemistry tests from other pharmacopeias) or introduction of a specific flame test to a specific monograph. The proposed revision of chapter Pharmacopeial Forum.
191
is included in this issue of
The potential impact of changes to 191 is significant. Wet-chemistry tests have been used for many years and may still provide valid options; however, a revised chapter 191 will
http://www.usppf.com/pf/pub/data/v412/GEN_STIMULI_412_s201224.xml
3/24/2015
41(2) Stimuli to the Revision Process: Modernization of Identification Tests in USP-NF
Page 2 of 7
provide greater flexibility by providing options for wet-chemical and/or instrumental approaches to identification tests. Although qualitative wet-chemistry tests may continue to be used, the instrumental options in the proposed revision of the chapter can provide results that are less subjective, and in many cases, quantitative. If a quantitative test is required for a given ion in a monograph, an additional qualitative identification test is usually not necessary. In cases where multiple identification tests are required in a monograph, different (nonredundant) methods must be used. For example, if an IR identification test with reference to chapter 197 is included in a monograph and an additional identification test is included in the monograph with reference to chapter 191 , a test option from chapter 191 other than IR must be used. RATIONALE FOR MODERNIZATION—SURVEY RESULTS In August 2011, USP staff conducted an international survey to obtain industry feedback regarding chapter 191 and the potential need to modernize the chapter. A total of 392 responses to the online survey were received. The survey was designed to determine industry practices for identification testing and preferences regarding chapter 191 . Questions in the survey addressed demographics, use of chapter 191 , use of alternatives to chapter 191 tests, level of satisfaction with chapter 191 , and suggestions for modernization of chapter 191 . The survey revealed that although many of the wet-chemistry tests in chapter 191 are used (because they are the official tests), almost 65% of the respondents use, or would like to use, instrumental tests to fulfill identification test requirements. Some alternative tests are already being used to quantify counterions, to provide process information, and to meet regulatory requirements. Other survey results indicated a strong interest in harmonizing tests with other pharmacopeias and in clarifying the procedures as well as the acceptance criteria. There has also been interest from the Food and Drug Administration in more rigorous identification tests that could help in the fight against adulteration and counterfeiting. Table 1 lists the top 10 ions tested by survey respondents. Also included in Table 1 is the number of monographs referencing chapter 191 for each ion. Not surprisingly, the listing of the top ions identified by survey respondents overlaps significantly with the most frequently referenced ions in monographs. Table 1. Top 10 Ions Tested by Survey Respondents and Frequency of Reference to Chapter
Ion
191
in USP Monographs (Second Supplement to USP 36–NF 31) Number of USP Monographs Percentage of Survey Respondents Testing for Ion Referencing Chapter 191 for Ion Identification (rank) (in rank order)
http://www.usppf.com/pf/pub/data/v412/GEN_STIMULI_412_s201224.xml
3/24/2015
41(2) Stimuli to the Revision Process: Modernization of Identification Tests in USP-NF
Chloride Sodium Calcium Sulfate Potassium Phosphate Magnesium Bicarbonate/Carbonate Iron/Ferrous salts Acetate
86% 75% 63% 61% 60% 57% 55% 52% 51% 50%
Page 3 of 7
286 (1) 195 (2) 60 (5) 103 (3) 79 (4) 28 (9) 50 (6) 16 (12)
