Charlotte Keenan

Best Practices for Use of Historical Control Data of Proliferative Rodent Lesions

CHARLOTTE KEENAN, SUSAN ELMORE, SABINE FRANCKE-CARROLL, RAMON KEMP, ROY KERLIN, SHYAMAL PEDDADA, JOHN PLETCHER, MATTHIAS RINKE, STEPHEN PETER SCHMIDT, IAN TAYLOR, AND DOUGLAS C. WOLF GlaxoSmithKline, King of Prussia, Pennsylvania, USA National Toxicology Program (NTP), National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, North Carolina, USA Center for Food Safety and Applied Nutrition (CFSAN), U.S. Food and Drug Administration, College Park, Maryland, USA Merck Research Laboratories, Riom, France Pfizer Inc., Groton, Connecticut, USA NIEHS, Research Triangle Park, North Carolina, USA Charles River, Frederick, Maryland, USA Bayer Schering Pharma AG, Wuppertal, Germany Huntingdon Life Sciences, Eye, United Kingdom U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA

International Harmonization of Toxicologic Pathology Nomenclature: An Overview and Review of Basic Principles

The International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice is a global project that is publishing criteria for both proliferative and nonproliferative changes in laboratory animals. This paper presents a set of general suggestions for terminology across systems. These suggestions include the use of diagnostic versus descriptive terms, modifiers, combination terms, and grading systems; and the use of thresholds, synonyms, and terminology for some processes that are common to several organ systems. The purpose of this paper is to help the reader understand some of the basic principles underlying the International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice process.

The Value of Historical Control Data—Scientific Advantages for Pathologists, Industry and Agencies

Historical control tumor data are useful in the interpretation of long-term rodent carcinogenicity bioassays, especially to assess the occurrence of rare tumors and marginally increased tumor incidences. The major prerequisites to compare historical control data with studies under evaluation are the validity and consistency of the respective databases. The RITA (Registry of Industrial Toxicology Animal-data) database for historical data of tumors and pre-neoplastic lesions collects data according to highly standardized procedures including tissue sampling and trimming, histopathology according to internationally harmonized nomenclature and diagnostic criteria, and peer review. All lesions that are entered are unanimously diagnosed according to IARC (International Agency for Research on Cancer)/WHO criteria. The validity of data is additionally confirmed by a complete peer review performed by a database pathologist. Equivocal diagnoses and selected cases are additionally submitted to a panel of RITA pathologists. In the RITA database, there are currently 10,896 rats from 106 studies with more than 17,604 primary tumors and 16,551 pre-neoplastic lesions. The RITA database for historical control data for Wistar and Sprague Dawley rats as well as for different mouse strains is briefl ydescribed. Based upon RITA background data, the survival rate of Wistar rats has been consistent over a period of 10 years. The occurrence of tumor-bearing animals also shows a stable percentage over a decade. Additionally, examples of how historical control data may support carcinogenic risk assessment in cases of rare tumors or marginally increased incidences of tumors and pre-neoplastic lesions are given.

Standard morphologic evaluation of the heart in the laboratory dog and monkey

The nonrodent species most commonly utilized in preclinical safety studies are the purpose-bred beagle dog and cynomolgus macaque (Macaca fascicularis). Potential effects of a new chemical entity (NCE) on the heart pose serious concerns; consequently in vivo testing is focused on detection of functional alterations as well as morphological changes. Macroscopic and microscopic evaluation of the heart is based on a standard survey of key structures to properly assess presence of spontaneous and potential drug-induced lesions. Evaluation of historical controls to determine type and frequency of background change is valuable, as studies with non-rodent species generally have a small sample size. Archived control dog and monkey data were retrospectively reviewed, including terminal body weight (BW), heart weight (HW), and archival glass slides of heart. Control dogs had minimal background changes that included myxomatous or cartilagenous change in the cardiac skeleton and a variable degree of vacuolation in Purkinje fibers. Control monkey hearts commonly contained inflammatory cell infiltrates, myocyte anisokaryosis, and handling artifacts, while myocyte degeneration, squamous plaques, pigment, and intimal plaques were occasionally observed. These findings highlight the utility of consistently recorded and readily accessible archived control data when attempting to discern background spontaneous changes and artifacts from test-article induced changes.

The North American Control Animal Database: A Resource Based on Standardized Nomenclature and Diagnostic Criteria

Historical control data have been shown to be valuable in the interpretation and evaluation of results from rodent carcinogenicity studies. Standardization of terminology and histopathology procedures is a prerequisite for meaningful comparison of control data across studies and analysis of potential carcinogenic effects. Standardization is particularly critical for the construction of a database that includes incidence data from different studies evaluated by pathologists in different laboratories. Standardized nomenclature and diagnostic criteria have been established for neoplasms and proliferative lesions. Efforts of the National Toxicology Program, the Society of Toxicologic Pathology (STP), and the Registry of Industrial Toxicology Animal-data (RITA) have led to a harmonized pathology nomenclature for the rat and the mouse. This nomenclature with detailed descriptions of lesions is available in publications by the STP and International Agency for Research on Cancer (IARC). A listing of these terms is available on the World Wide Web. Utilizing the model established by RITA and working with the International Life Sciences Institute (ILSI), companies with laboratories in North America formed a working group in 1994 to establish and maintain a database of neoplastic and proliferative lesions from control animals in carcinogenicity studies. The rationale for development of the North American Control Animal Database (NACAD), the factors that influence tumor incidence, operation of the database, and the benefits to be realized by using a standardized approach are discussed.

Regulatory Forum Commentary* Through the Looking Glass—SENDing the Pathology Data We Have INHAND

During 2011, International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice (INHAND) Global Editorial Steering Committee representatives had discussions with representatives of the Food and Drug Administration (FDA) Center for Drug Evaluation and Research (CDER), Clinical Data Interchange Standards Consortium (CDISC), and the National Cancer Institute (NCI) Enterprise Vocabulary Services (EVS) to examine the potential use of INHAND terminology for SEND (Standard for Exchange of Nonclinical Data) submissions to the FDA. The interest in utilizing the INHAND nomenclature, based on input from industry and government toxicologists as well as information technology specialists, suggests that there will be wide acceptance of INHAND nomenclature. The purpose of this article is 2-fold: (1) to provide a brief historical background on the development of SEND and how it is structured and (2) to discuss the impact of SEND on toxicologic pathology and the role of INHAND.

Industry Survey of Approaches to Examination and Terminology of Spontaneous Changes in the Heart of Young Rats

Toxicologic pathologists are tasked with morphologic evaluation of tissues in animal toxicity studies to ascertain drug or chemical-related effects. These assessments are based on knowledge of the species and spectrum of morphologic changes that occur in the untreated control population. Within the rat heart, a number of morphologic changes have been observed as spontaneous events in control populations, one of the most common being myocardial degeneration or cardiomyopathy (Greaves 2000; King and Russell 2006; Kemi et al. 2000). Experience suggests this change can be observed with a highly variable incidence in very young rats and increases in severity with age; however, many classic literature descriptions identify this as a condition of aging rats. To gain better understanding of the industry’s approach to sampling the heart and terminology in common use in young rats, an informal survey was conducted in 2009 that focused on rat studies of 7 days’ to 28 days’ duration. The survey was sent to 89 individuals who represent the pharmaceutical (53), contract research organization (CRO) and consultant (35), or chemical industries (1). Responses were received from 36 contacts, for a 40.5% return rate. Respondents were asked if survey results could be published; all but one agreed. Sectors represented in the reported data include 20 pharmaceutical (13 North America, 5 Europe, 2 Japan), 9 CRO (6 Europe, 3 North America), 4 consultants (2 Europe, 2 North America), 1 chemical company (Japan), and 1 anonymous (unknown affiliation). A graphical summary of selected survey questions is presented in Figure 1A-J. The following general trends in short-term studies (less than 28 days) were noted:

Potential for a Global Historical Control Database for Proliferative Rodent Lesions

CHARLOTTE KEENAN (CHAIR), SUSAN ELMORE, SABINE FRANCKE-CARROLL, ROY KERLIN, SHYAMAL PEDDADA, JOHN PLETCHER, MATTHIAS RINKE, STEPHEN PETER SCHMIDT, IAN TAYLOR, AND DOUGLAS C. WOLF GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland 20740, USA Pfizer Inc., Groton, Connecticut 06340, USA National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA Charles River, Frederick, Maryland 21701, USA Bayer Schering Pharma AG, Wuppertal, Germany Huntingdon Life Sciences, Eye, Suffolk IP23 7PX, UK U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND) Progress to Date and Future Plans

The International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice proposal (INHAND) has been operational since 2005. A Global Editorial Steering Committee manages the overall objectives of the project, and the development of harmonized terminology for each organ system is the responsibility of the Organ Working Groups, drawing upon experts from North America, Europe, and Japan. Great progress has been made with 9 systems published to date—respiratory, hepatobiliary, urinary, central/peripheral nervous systems, male reproductive and mammary, zymbals, clitoral, and preputial glands in Toxicologic Pathology and the integument and soft tissue and female reproductive in the Journal of Toxicologic Pathology as supplements and on a Web site—www.goReni.org. INHAND nomenclature guides offer diagnostic criteria and guidelines for recording lesions observed in rodent toxicity and carcinogenicity studies. The guides provide representative photomicrographs of morphologic changes, information regarding pathogenesis, and key references. The purpose of this brief communication is to provide an update on the progress of INHAND.

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND) progress to date and future plans

The INHAND Proposal (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) has been operational since 2005. A Global Editorial Steering Committee (GESC) manages the overall objectives of the project and the development of harmonized terminology for each organ system is the responsibility of the Organ Working Groups (OWG), drawing upon experts from North America, Europe and Japan.Great progress has been made with 9 systems published to date – Respiratory, Hepatobiliary, Urinary, Central/Peripheral Nervous Systems, Male Reproductive and Mammary, Zymbals, Clitoral and Preputial Glands in Toxicologic Pathology and the Integument and Soft Tissue and Female Reproductive System in the Journal of Toxicologic Pathology as supplements and on a web site – www.goreni.org. INHAND nomenclature guides offer diagnostic criteria and guidelines for recording lesions observed in rodent toxicity and carcinogenicity studies. The guides provide representative photo-micrographs of morphologic changes, information regarding pathogenesis, and key references. During 2012, INHAND GESC representatives attended meetings with representatives of the FDA Center for Drug Evaluation and Research (CDER), Clinical Data Interchange Standards Consortium (CDISC), and the National Cancer Institute (NCI) Enterprise Vocabulary Services (EVS) to begin incorporation of INHAND terminology as preferred terminology for SEND (Standard for Exchange of Nonclinical Data) submissions to the FDA. The interest in utilizing the INHAND nomenclature, based on input from industry and government toxicologists as well as information technology specialists, suggests that there will be wide acceptance of this nomenclature. The purpose of this publication is to provide an update on the progress of INHAND.