In genotoxicity testing of pharmaceuticals the rodent alkaline comet assay is being increasingly used as a second in vivo assay in addition to the in vivo micronucleus assay to mitigate in vitro positive results as recommended by the ICH S2(R1) guideline. This paper summarizes a survey suggested by the Safety Working Party of European Medicines Agency (EMA), and conducted by the European Federation of Pharmaceutical Industries and Associations (EFPIA) to investigate the experience among European pharmaceutical companies by conducting the in vivo comet assay for regulatory purpose. A special focus was given on the typology of the obtained results and to identify potential difficulties encountered with the interpretation of study data. The participating companies reported a total of 147 studies (conducted in-house or outsourced) and shared the conclusion on the comet assay response for 136 studies. Most of the studies were negative (118/136). Only about 10% (14/136 studies) of the comet assays showed a positive response. None of the positive comet assay results were clearly associated with organ toxicity indicating that the positive responses are not due to cytotoxic effects of the compound in the tissue examined. The number of comet assays with an equivocal or inconclusive response was rare, respectively <1% (1/147 studies) and 2% (3/147 studies). In case additional information (e.g. repeat assay, organ toxicity, metabolism, tissue exposure) would have been available for evaluation, a final conclusion could most probably have been drawn for most or all of these studies. All (46) negative in vivo comet assays submitted alongside with a negative in vivo micronucleus assay were accepted by the regulatory authorities to mitigate a positive in vitro mammalian cell assay following the current ICH S2 guidance. The survey results demonstrate the robustness of the comet assay and the regulatory acceptance of the current ICH S2 guidance.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.mrgentox.2014.09.008 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Assessing the Potential Synergistic/Antagonistic Effects of Citrinin and Cannabidiol on SH-SY5Y, HepG2, HEK293 Cell Lines, and Human Lymphocytes.
Toxins (Basel)
December 2024
Division of Toxicology, Institute for Medical Research and Occupational Health, HR-10 000 Zagreb, Croatia.
The increasing use of products for medicinal, dietary, and recreational purposes has raised concerns about mycotoxin contamination in cannabis and hemp. Mycotoxins persist in these products' post-processing, posing health risks via multiple exposure routes. This study investigated cytotoxic and genotoxic interactions between cannabidiol (CBD) and the mycotoxin citrinin (CIT) using human cell models: SH-SY5Y, HepG2, HEK293, and peripheral blood lymphocytes.
View Article and Find Full Text PDFGenetic instability of a single exposure to sevoflurane at different concentrations in monitored mice.
Environ Mol Mutagen
December 2024
GENOTOX Laboratory, São Paulo State University (UNESP), Medical School, Botucatu, Brazil.
Sevoflurane is an inhalation anesthetic widely used for general anesthesia, but its genotoxic potential is controversial in clinical studies. It is unknown whether the effects are due to surgery or the anesthetic. Thus, for the first time, the present study investigated genotoxicity in peripheral blood cells and in target organs (liver, lung, and kidney) and micronucleus (MN) in the bone marrow of a single exposure to sevoflurane at three different concentrations in monitored mice.
View Article and Find Full Text PDFHazard assessment of nanomaterials: how to meet the requirements for (next generation) risk assessment.
Part Fibre Toxicol
December 2024
Health Effects Laboratory, Department of Environmental Chemistry and Health Effects, NILU, 2007, Kjeller, Norway.
Background: Hazard and risk assessment of nanomaterials (NMs) face challenges due to, among others, the numerous existing nanoforms, discordant data and conflicting results found in the literature, and specific challenges in the application of strategies such as grouping and read-across, emphasizing the need for New Approach Methodologies (NAMs) to support Next Generation Risk Assessment (NGRA). Here these challenges are addressed in a study that couples physico-chemical characterization with in vitro investigations and in silico similarity analyses for nine nanoforms, having different chemical composition, sizes, aggregation states and shapes. For cytotoxicity assessment, three methods (Alamar Blue, Colony Forming Efficiency, and Electric Cell-Substrate Impedance Sensing) are applied in a cross-validation approach to support NAMs implementation into NGRA.
View Article and Find Full Text PDFIMPACT OF ASTAXANTHIN ON MANIFESTATIONS OF THE DIRECT AND RESCUE TUMOR-INDUCED BYSTANDER EFFECT.
Probl Radiac Med Radiobiol
December 2024
State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine», 53 Yuriia Illienka Str., Kyiv, 04050, Ukraine.
Objective: to investigate the reciprocal impact on the genome of malignant and normal human peripheral bloodlymphocytes under their co-culture and the possibility to modify the effects by astaxanthin.
Methods: Separate and joint/separate culturing of peripheral blood lymphocytes (PBL) of the chronic lymphocyticleukemia (CLL) patients (n = 6) and conditionally healthy individuals (n = 6), Comet assay method, fluorescencemicroscopy with automated software for the analysis of results, statistical methods.
Results: Both direct and rescue tumour-induced bystander effects were observed under the joint/separate culturing of blood lymphocytes of conditionally healthy individuals (the bystander cells) and blood cells from CLL patients(the inducer cells).
ANALYSIS OF DNA METHYLATION CHANGES IN MANIFESTATION OF DIRECT AND RESCUE BYSTANDER EFFECTS.
Probl Radiac Med Radiobiol
December 2024
Educational and Scientific Center «Institute of Biology and Medicine» of the Taras Shevchenko Kyiv National University, 64/13 Volodymyrska Str., Kyiv, 01601, Ukraine.
Objective: to investigate changes in DNA methylation in bystander and inducer cells during the manifestation ofdirect and rescue bystander effects.
Methods: Separate and co-cultivation of peripheral blood lymphocytes (PBL) of 10 conditionally healthy individuals; γ-quantum irradiation (IBL-237C emitter); modified comet electrophoresis method (Comet assay) under neutralconditions using the methylation-sensitive restriction enzyme HpaII; fluorescence microscopy with an automatedcomputer software system for analyzing the results; statistical methods.
Results: The level of DNA methylation in PBL was quantitatively assessed using DNA migration parameters inagarose gel: the length of the comet tail (in μm), the percentage of DNA in the tail part of the comet, and TailMoment (TM), which simultaneously takes into account both the amount of DNA in the tail part of the comet andthe length of the tail.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!