Quantitative Structure Activity Relationships: An Overview
Date and Time: Tuesday, November 14, 2017, 11:00 AM to 12:00 Noon EST
Speaker: Dr. Prachi Pradeep, US EPA/ORISE
Brief Abstract: Chemical risk assessment is often limited by the lack of experimental toxicity data for a large number of diverse chemicals. In the absence of experimental data, potential chemical hazard is often predicted using data gap filling techniques such as quantitative structure activity relationship (QSAR) models. QSARs are theoretical models that relate a quantitative measure of chemical structure to a physical property or a biological effect. QSAR tools are a widely utilized alternative to time-consuming clinical and animal testing methods, yet concerns over reliability and uncertainty limit application of QSAR models for regulatory chemical risk assessments. The reliability of a QSAR model depends on the quality and quantity of experimental training data and the applicability domain of the model. This talk will describe the basics concepts and best practices in QSAR modeling, principles associated with validation of QSAR models, summary of available QSAR tools, limitations and challenges in the acceptance of QSAR models within a regulatory framework, and the current status and prospects of QSAR modeling methods in the medical devices community.
Regulations, Standards and Practices for Biocompatibility & Toxicology Assessment in China
Date and Time: Friday, October 13, 2017 11:00 AM to 12:00 Noon EST
Speaker: Chenghu Liu, Director, Biological Evaluation Department, Shandong Quality Inspection Center for Medical Devices Jinan, China
Brief Abstract: The purpose of this webinar is to help participants learn about evaluating biocompatibility of medical devices in China. In recent years, the China Food and Drug Administration (CFDA) has released several important policies and regulations that impact local medical device submission and registration. At the same time, local biocompatibility evaluation standards have also evolved to align with advances in the global ISO 10993 standards. Technical Committee 248 of the Standardization Administration of the People’s Republic of China (SAC) is currently based at the Shandong Quality Inspection Center for Medical Devices and is chartered with establishing local biocompatibility standards. The current Chinese GB16886 standards were adopted from the ISO 10993 standards and are essential for biocompatibility evaluation in China. In addition, China has also developed specific test method standards to supplement the GB16886 standards. This webinar will provide an overview of the current status and future trends in biocompatibility evaluation, regulatory requirements, and best practices in China.
ISO 10993–1 Biological Evaluation—The Risk Management of Unstudied Extractables and Leachables (E&L) Impurities in Medical Devices and Combination Products
Date: April 10, 2017, 11:00 AM–12:30 PM EST
Use of In Silico Modelling in Preclinical Testing, Co-Sponsored with IVAMSS
Speaker: Kim Li, PhD, DABT, MPH, Amgen Inc. Thousand Oaks, CA
Abstract: In 2016, the FDA issued final guidance on the use of ISO 10993–1 “Biological evaluation of medical devices—Part 1: Evaluation and testing within a risk management process.” The guidance describes a framework whereby chemical characterization of device materials and the toxicology assessment of the extractables and leachables (E&L) impurities may reduce certain biocompatibility testing requirements.
The chemical characterization of the device materials and components is often a comprehensive profile with known as well as tentatively identified structures (TIS). TIS may result from degradation and/or fragmentation of the chemical additives and processing aids used in the production of polymeric materials. The polymeric materials of construction in medical devices are also common materials of construction for bioporocess materials and primary containers that have direct contact with drug product. Therefore the widespread use of polymeric materials underscores the need for a holistic approach in the evaluation of leachables in combination products. Protein therapeutics are more susceptible than chemically synthesized drug products to the leachables that may impact product safety and quality.
While the risk assessment of known chemical compounds is well established based on the known toxicity endpoints (e.g. target organ toxicity, mutagenicity, carcinogenicity and reproductive/developmental toxicity), TIS are unstudied chemicals for which the current risk assessment practices and threshold concepts may not apply. However, it is neither practical nor technically feasible to conduct animal testing on TIS. On the other hand, biocompatibility tests using extracts as described in ISO 10993–12 do not have the specificity nor sensitivity offered by chemical characterization and toxicology assessment of the E&L profiles of the test materials.
This presentation will examine the science- and risk-based decision analysis to integrate the current threshold concepts with in silico tools for the screening of TIS impurities. The presentation will discuss the three different modules of Toxtree (IdeaConsult): in vitro mutagenicity (Ames test) prediction, Cramer classification for systemic toxicity and protein binding alerts. When integrated into a systematic analysis, these modules offer understanding of the chemical reactivity and toxicity for the TIS, which may form the basis to reduce certain unnecessary biocompatibility testing.
Animal-Specific Modelling for the 3R in Preclinical Assessment: A Bone Drugs Example
Speaker: Marco Viceconti, Executive Director, Insigneo Institute for In Silico Medicine, The University of Sheffield and Sheffield Teaching Hospital NHS Foundation Trust
Abstract: There is a growing societal pressure toward the Reduction, Refinement, and Replacement (3R) of animal experimentation in most developed countries, primarily motivated by ethical considerations. But there is also a growing concern that the approach used to test the safety and the efficacy of products potentially affecting human health needs some serious revision: a 2014 report of the Tufts Center for the Study of Drug Development suggests that the cost to take to the market a new drug today exceed US$2.5bn; most of these money is spent during the clinical assessment, but it is probably the preclinical assessment to be blamed most, if (according to Pharmaceutical Research and Manufacturers of America) out of five compounds cleared in the preclinical phase, only one will survive the clinical trials. This means that pre-clinical trials, which are mostly based on animal experimentation, are wrong four times out of five, and this is clearly unacceptable.
Under these combined pressures, the drive for the 3R is combining with the need for the development of Non-Animal Alternatives that not only help to solve this delicate ethical conundrum, but also improve our ability to predict safety and efficacy of a new product before it is tested on humans. There are other industrial sectors that develop products potentially hazardous for human health; if a large airliner crashes, or a nuclear power plant blows, hundreds if not thousands of lives can be at risk, and the environmental damage could eventually affect many more. But in none of these sectors it is conceivable to evaluate safety by trial and error, which is at the basis of the preclinical testing of products affecting human health. These products are most entirely tested through laboratory experiments, and the massive use of modelling and simulation. However, until recently no human health products regulator would even consider in a submission evidences obtained with modelling and simulation.
Here we present the results of a research funded by the UK National Centre for the Reduction, Refinement, and Replacement of animal experimentation (NC3R), where a well establish murine model widely used to test preclinically the efficacy of bone drugs was critically revised using animal-specific modelling based on longitudinal imaging. The methods developed were able to reduce of 63% the number of animals required to achieve statistical significance. But more important, the possibility of observing the effect of the drug being tested over large anatomical volumes, and over time in the same animal non-invasively, has put in serious question the need for a series of interventions that if removed would significantly refine this animal experiment. Last, we will present some preliminary results where animal-specific models are used to partially replace animal experimentation altogether, using an approach call in silico augmented study. We will conclude by suggesting that animal-specific modelling, when combined with human-specific model could produce conclusive evidences on non-animal alternatives are better suited than animal models in predicting the response in humans.
Effects of Nanoscale Particles in the Brain
Speaker: Alison Elder, PhD, Associate Professor of Toxicology in the Department of Environmental Medicine at the University of Rochester Medical Center.
Research Focus: Toxicology of Inhaled Ultrafine Particles and Engineered Nanomaterials
MDCPSS—ISO 10993-4 Biological Evaluation of Medical Devices: Selection of Tests for Interaction with Blood
Speaker: Michael Wolf, BS, MS, Medtronic Inc.
Abstract: For medical device companies with blood-contacting products, the ISO 10993-4 guidance document is important because it defines general requirements and considerations for evaluating interactions of concern between the devices and blood. The document describes: (1) classification of blood-contacting medical devices based upon intended use and duration of contact as defined in ISO 10993-1, (2) fundamental principles and scientific bases behind various methods of evaluating interactions of devices with blood, and (3) a structured selection of tests for consideration based upon intended use and blood contact duration. In short, this standard is a guide for start-up companies, established industry, and regulatory agencies to assess the apparent pre-clinical blood compatibility of candidate cardiovascular devices and materials intended for human blood contact applications.
The foundation of ISO 10993-4 has several sources. However, since its inception in 2002, the document has received only minor revision. Over the past several years the revision of this document has involved review of hundreds of comments from around the world, with the FDIS recommended for formal approval in 2016. Concisely, the new document provides a simplified process flow diagram for high level planning decisions, a reduced and simplified table of example devices vs. testing categories for consideration, and a streamlined table of actual tests for consideration in each test category.
Importantly, the standard suggests more opportunities for meaningful in vitro testing to supplement or replace certain animal testing. More emphasis is also placed on the importance of testing blood contacting devices for impact on thrombosis.
Evaluation of Medical Devices for Genetic Toxicity: A Global Perspective
Webinar Recording | Presentation Slides
The current presentation will discuss the topics below:
Use of International Standard ISO 10993-1, “Biological Evaluation of Medical Devices—Part 1: Evaluation and Testing within a Risk Management Process”
Hosted by: US FDASpeakers: Jennifer Goode, Office of Device Evaluation, Center for Devices and Radiological Health
Date: Thursday, July 21, 2016, 1:00 PM–2:30 PM EST
Abbreviated Abstract: On July 21, 2016, the US FDA held a webinar for industry to review the Use of International Standard ISO 10993-1, “Biological Evaluation of Medical Devices—Part 1: Evaluation and Testing within a Risk Management Process” final guidance document. The recommendations in this final guidance clarify and update how medical device developers may use ISO 10993-1 standard in their premarket submission to determine the potential for an unacceptable adverse biological response resulting from contact of a medical device with the body. This final guidance replaces the Office of Device Evaluation (ODE) Blue Book Memorandum #G95-1 (1995), entitled “Use of International Standard ISO-10993, ’Biological Evaluation of Medical Devices—Part 1: Evaluation and Testing.”
Exploring Certifications in General Toxicology: An Introduction to ABT/ERT/ATS Certification
Hosted by: American College of Toxicology
Speakers: Bas Blaauboer, PhD, Emeritus Professor of Toxicology at the Division of Toxicology, Institute for Risk Assessment Sciences, Utrecht University, Chair of the Registration Subcommittee of EUROTOX; Michael Holsapple, PhD, ATS, Director and Endowed Chair at the Center for Research on Ingredient Safety/Professor of Food Science & Human Nutrition at Michigan State University, President of ATS; and Christopher P. Weis, PhD, DABT, Toxicology Liaison/Senior Adviser, Office of the Director, National Institute of Environmental Health Sciences, Vice-President of ABT
Abbreviated Abstract: Professional toxicologists across the world pursue certifications to add value to their credentials as part of their career development. There are three primary professional certifications in toxicology.
I. The American Board of Toxicology (ABT) offers Diplomate status to qualified individuals who demonstrate relevant education, actively practice in toxicology, and pass a comprehensive examination.
II. The European Registry of Toxicologists (ERT) includes toxicologists, who demonstrate knowledge of the major areas of toxicology. This knowledge can be acquired by either following an appropriate academic program, e.g. by attending courses, or by practical experience and on the job training. At least 5 years of relevant toxicological experience is needed.
III. The Academy of Toxicological Sciences (ATS) awards Fellow status to individuals with demonstrated contributions to the discipline of toxicology over their career, as judged by peer review of relevant education, professional practice in toxicology, and professional recognition.
Each of these three certifications is complementary, professionally valuable, and has unique requirements for eligibility. This webinar will provide a primer on eligibility, value, and maintenance for each certification followed by a Q&A session.
Webinar: SCENIHR Opinion on the Determination of Potential Health Effects of Nanomaterials Used in Medical Devices
Speaker: Wim De Jong, DVM, PhD, Centre for Health Protection at the National Institute for Public Health and the Environment (RIVM)
Abbreviated Abstract: The use of nanomaterials in medical devices poses a challenge for the safety evaluation and risk assessment of these medical devices as the specific character of the nanomaterial used should be taken into consideration. The various aspects of safety evaluation and risk assessment of medical devices containing nanomaterials are addressed in this Guidance. The use of nanomaterials in medical devices can vary considerably. Examples are the use of free nanomaterials being a medical device and administered to the patient as such (e.g. iron oxide or gold nanomaterials for heat therapy against cancer), free nanomaterials in a paste-like formulation (e.g. dental filling composites), free nanomaterials added to a medical device (e.g. nanosilver as antibacterial agent in wound dressings), fixed nanomaterials forming a coating on implants to increase biocompatibility (e.g. nano-hydroxyapatite) or to prevent infection (e.g. nano-silver), or embedded nanomaterials to strengthen biomaterials (e.g. carbon nanotubes in a catheter wall). In all these cases the potential exposure to the nanomaterials should be considered. It is additionally recognised that wear-and-tear of medical devices may result in the generation of nanosized particles even when the medical device itself does not contain nanomaterials.
Guidance is provided on physico-chemical characterisation of nanomaterials, the determination of hazards associated with the use of nanomaterials, and risk assessment for the use of nanomaterials in medical devices. The safety evaluation of the nanomaterials used in medical devices is discussed in the context of the general framework for biological evaluation of medical devices as described in the ISO 10993-1:2009 standard. Therefore, the risk assessment should be performed taking into consideration the type of device, the type of tissue contact, and the contact duration, thus identifying the specific exposure scenario.
A phased approach is recommended for evaluating the risk of the use of nanomaterials in medical devices based on potential release and characteristics of the nanomaterials to avoid unnecessary testing. In phase 1 an evaluation of the potential for the device to release nanoparticles either directly or due to wear of the device during use should be carried out. In phase 2 the aim is to determine the distribution of the particles released and also their persistence potential. In phase 3 the hazard is assessed using appropriate toxicity tests taking account of the exposure characteristics and potential for persistence in specific organs. This will provide input for the final risk characterisation (phase 4). The estimated risk needs to be compared to the risk from the use of comparable devices not incorporating nanomaterials in judging the acceptability of the risk. In conclusion, the potential risk from the use of nanomaterials in medical devices is mainly associated with the possibility for release of free nanoparticles from the device and the duration of exposure.
Webinar: The Threshold of Toxicological Concern: Application to Medical Devices and Pharmaceuticals.
Speakers: Ron Brown, FDA, CDRH, and Douglas Ball, Pfizer
Abstract: Over the past 50 years, this question of assessing human health risk of unstudied or incompletely characterized chemicals has been the subject of many publications. The most widely accepted scientific approach to assess the risk of exposure to incompletely characterized chemicals is to consider a level of exposure for all chemicals below which there is no appreciable risk to human health; a threshold of toxicological concern (TTC). The concept of a TTC holds true across a wide spectrum of toxicity endpoints, such as genotoxicity, carcinogenicity, neurotoxicity, reproductive and developmental toxicity and acute and repeated dose systemic toxicity (Munro and Kroes [JECFA], 1998; Muller, 2006; Delaney et al., 2007; Bernauer et al., 2008; van Ravenzway, 2011). The literature provides evidence of the scientific community’s acceptance of the TTC concept, which many regulatory authorities around the world have also endorsed. The TTC concept has been applied to many applications including food packaging, food flavorings, pesticide metabolites in groundwater, pharmaceuticals, herbal substances and preparations and genotoxic drug impurities.
Application of the TTC to Pharmaceuticals: In 2013, the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) published a draft consensus guideline on the Assessment and Control of DNA Reactive (Mutagenic) impurities in Pharmaceuticals to Limit Potential Carcinogenic Risk, M7. The ICH M7, which applies to products to the pharmaceutical market and to combination drug devices, was written “to provide a practical framework that can be applied for the identification, categorization, qualification, and control of these mutagenic impurities to limit potential carcinogenic risk.” The guideline also extends the TTC to less than lifetime patient exposures by allowing for higher thresholds for shorter exposure duration, such as during clinical drug trials. Douglas Ball (Pfizer) will provide background on the derivation of the TTC and how it is applied in pharmaceuticals and the pharmaceutical industry through case studies including a process-related mutagenic impurity and Leachable & Extractable qualification using a modified Cramer Classification strategy.
Application of the TTC to Medical Devices: Ron Brown will focus on how the proposed application of the TTC concept for Leachables & Extractables from medical device materials is similar to/different than the approach for impurities in drugs. The International Standards Organization (ISO) Technical Committee 121 has begun work on the development of a TTC approach for volatile compounds released from respiratory devices.
Webinar: Medical Device Color Additives: Legislative History and Regulatory Perspective
Presenter: Brenda Seidman, MS, PhD, RAC
MDCPSS 2015 Annual Reception
Date: Tuesday, March 24, 2015, 6:00 PM–7:30 PM
Continuing Education Courses
Date: Sunday, March 22, 2015
MDCPSS Fall Webinar: Quantitative Risk Assessment of the Genotoxicity and Tumorigenicity of CoCr-Containing Hip Implants
Date: September 24, 2014, 12:00 Noon
Description: Cobalt-chromium (CoCr) alloys have long been used in metal-containing hip implants because of their biocompatibility. Like all implant materials, CoCr alloys undergo some degree of wear and corrosion in vivo, and as a result implant patients experience blood and tissue Co and Cr(III) concentrations that are higher than background levels associated with dietary intake. Although to date epidemiology studies do not indicate an increased incidence of cancer in patients with hip implants, questions continue to be raised about the potential cancer risk posed by CoCr-containing implants. To address these concerns, the scientific literature investigating the genotoxic and tumorigenic effects of Co particles and ions, Cr particles and ions, CoCr alloy particles, as well as CoCr alloy implants was gathered, and NOAEL/LOAEL values were compared with body burdens of Co/Cr particles and ions that were calculated to exist in systemic tissues of hip implant patients under normal and excessive wear conditions. This presentation will illustrate the quantitative methods that were used to evaluate the weight-of-evidence regarding a causative relationship between CoCr-containing hip implants and increased cancer risk to determine whether the existing toxicology data support epidemiological findings.
Supporting Information: Toxicology-based cancer causation analysis of CoCr-containing hip implants: a quantitative assessment of genotoxicity and tumorigenicity studies. Christian WV, Oliver LD, Paustenbach DJ, Kreider ML, Finley BL. J Appl Toxicol. 2014 Sep;34(9):939–67.
Speaker Bio: Whitney V. Christian, PhD
Dr. Whitney V. Christian is a Health Scientist II with Cardno ChemRisk. He received a PhD in Molecular Toxicology from the Department of Environmental Medicine at the University of Rochester and a BA in Biology from Davidson College. Prior to attending graduate school he conducted cancer research in the Lineberger Comprehensive Cancer Center at the University of North Carolina at Chapel Hill. Combining his experience with genetics and toxicology, Dr. Christian possesses a unique understanding of gene-environment interactions and their contribution to the development of human disease. Dr. Christian’s areas of expertise include applied toxicology involving the use of exposure assessment methods, such as physiologically-based pharmacokinetic (PBPK) models, for quantitative risk assessment as well as specific areas of toxicology, including toxicokinetics, endocrine-disruption, metal toxicology, nanotoxicology, neurotoxicology, and genotoxicology/carcinogenesis.
Webinar: Use of Computational Toxicology for the Biological Evaluation of Medical Devices
Recording Date: Monday, June 23, 2014, 12:00 Noon
Description: The biological safety of medical devices is typically assessed by conducting biocompatibility testing of an extract of the device or the device itself; however, there is growing interest in an alternate approach that involves characterizing the chemical composition of the device extract and conducting a risk assessment on the compounds identified in the extract. One limitation to the practical implementation of this chemical characterization/risk assessment approach is the lack of toxicity data for many compounds released from device materials. To address this need, computational toxicology models, such as Quantitative Structure-Activity Relationship (QSAR) models, are being increasingly used to predict the toxicity or carcinogenicity of compounds based on their chemical structure. Efforts are underway to validate the predictive ability of QSAR models for compounds that are known to be released from device materials. This webinar will describe the computational modeling approaches available to predict the toxicity, mutagenicity, and carcinogenicity of compounds released from device materials and will explore ways to use model-derived predictions as part of the biological evaluation of a device, notably, to determine when certain types of testing may not be necessary.
MDCPSS 2014 Annual Reception
Date: Monday, March 24, 2014, 6:00 PM–7:30 PM
Location: Sheraton Paradise Valley Room
Symposium: In Vitro Medical Device Testing
Date: December 10–11, 2013
Location: Johns Hopkins University, Mt. Washington Conference Center, Baltimore, Maryland
This symposium, hosted by the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), will examine how the National Academy of Sciences, Toxicity Testing in the 21st Century can be applied to Medical Devices. The program will examine current requirements and testing approaches, followed by an examination of in vitro assays useful in medical device testing. The agenda includes speakers from industry, academia, and government.
Webinar: Medical Device Testing In Vitro—Pyrogenicity Testing and Beyond
Date: Friday, May 24, 2013, 11:59 AM
Speaker: Dr. Thomas Hartung
Description: In vitro methodologies are only slowly embraced by the field of medical device safety testing. The Limulus amebocyte lysate assay might be considered a forerunner for non-animal tests here as it is applied to eluates from medical devices in order to determine microbiological contaminations. However, this test is limited to Gram-negative bacterial endotoxin. More recently, assays based on the human fever reaction were developed. They make use of human white blood cells, which respond to many further stimuli. Especially the whole blood pyrogen assay allows to measure directly on the surface of the medical devices avoiding pyrogen eluation. Its adaptation to medical devices showed, that both eluation and depyrogenation by standard methodologies are not adequate to determine and remove pyrogen burden of medical devices. This test case is used to discuss opportunities and limitations for in vitro medical device testing in general. The webinar will benefit toxicologists involved with the safety assessment of medical devices, drugs, and combination devices.
Webinar: Current Testing and Alternative Methods for Assessment of Medical Device Blood-Material Interactions
Date: Friday, February 8, 2013, 12:00 Noon
Description: One of the most complex organs in the body is blood. There is a rich diversity of cells, proteins, small signaling molecules, electrolytes, etc., in the blood, and maintaining equilibrium in the interconnected systems is critical for health. Materials utilized in medical devices can interact directly or indirectly with blood and related systems, and ensuring and verifying hemocompatibility is a primary concern in interventional health care products. Technologies and strategies for assessing hemocomaptibility have appreciably advanced over the last several years, and the webinar will address emerging approaches. Any toxicologist with particular interest in hemocompatibility, or working on projects or programs where the blood or blood components are potential targets or effectors will benefit from the discussion. It should be noted that the speaker, Dr. Michael Wolf is a recognized expert in hemocompatibility, and is the chairperson for the ISO 10993 committee responsible for the ISO 10993 standard on hemocompatibility.
Webinar: Polyphenol-Eluting Stent reduces Restenosis and Promotes Vascular Healing in a Rat Model of Arterial Angioplasty and Stenting
Date: November 2, 2011, 11:00 AM
Presenter: Jim Kleinedler, LSU Health Science Center