View Study

Status: Ongoing First registered on: 18/10/2022

Last updated on: 20/10/2022

1. Study identification

EU PAS Register NumberEUPAS49355

Official titleIn vitro mutagenicity methodology for nitrosamines

Study title acronymInVitroNAmutagenicity

Study typeOther: In vitro study on mutagenicity of nitrosamines

Brief description of the studyThe project “In vitro mutagenicity methodology for nitrosamines” aims at generating a better understanding how the Ames test and the in vitro Comet assay can be methodologically optimized to reliably detect mutagenicity of different nitrosamines (NAs). A carefully selected set of reference NAs, active pharmaceutical ingredient (API)-derived NAs and supporting reference compounds will be used to demonstrate reproducibility, sensitivity (the proportion of genotoxic carcinogens that generate positive results), and specificity (the proportion of non-genotoxic compounds that generate a negative result) of each test model and provide data to estimate and compare the genotoxic potency of test compounds in the two different in vitro assays. One part of the project focuses on evaluation and optimization of the Ames test to improve its sensitivity in detecting the mutagenic potential of NAs with one focus on appropriate solvents and solvent concentrations as well as metabolising systems. The other part is dedicated to evaluation and optimization of the in vitro Comet assay with metabolically competent liver cell models (primary rat and human hepatocytes versus HepG2 cells) as a complementary or alternative assay for detection of potentially mutagenic/carcinogenic NAs and for respective risk assessment. Determination of compound solubility, compound puritiy and determination of metabolic competence of both S9 fractions and cell models will be part of the study.

Was this study requested by a regulator?Yes: EMA

Is the study required by a Risk Management Plan (RMP)? Not applicable

Regulatory procedure number (RMP Category 1 and 2 studies only)Not applicable

Other study registration identification numbers and URLs as applicableSPECIFIC CONTRACT No. 02 implementing framework contract No. EMA/2020/46/L1.02

2. Research centres and Investigator details

Coordinating study entity

Centre nameFraunhofer Institute for Toxicology and Experimental Medicine ITEM

Centre locationHannover, Germany

Details of (Primary) lead investigator

Title Dr

Last name Ziemann

First name Christina

Is this study being carried out with the collaboration of a research network?

Other centres where this study is being conducted

Multiple centres

In total how many centres are involved in this Study?6

Federal Institute for Drugs and Medical Devices (BfArM), Bonn, Germany

Technical University Kaiserslautern, Kaiserslautern, Germany

ICCR-Rossdorf, Rossdorf, Germany

Swansea University Medical School, Swansea, UK

Leadscope, Columbus, Ohio, USA

Countries in which this study is being conducted

International study

Germany

United Kingdom

United States

3. Study timelines: initial administrative steps, progress reports and final report

PlannedActual

Date when funding contract was signed09/08/202109/08/2021

Start date of data collection01/01/202201/01/2022

Start date of data analysis04/10/2022

Date of interim report, if expected

Date of final study report30/06/2023

4. Sources of funding

Please provide estimates of the percentage of funding by source for this study

Names(s)Approximate % funding

Pharmaceutical companies

Charities

Government bodyEMA100

Research councils

EU funding scheme

5. Contact details for enquiries

Scientific Enquiries

Title Dr

Last name Ziemann

First name Christina

Address line 1Nikolai-Fuchs-Str. 1

Address line 2

Address line 3

CityHannover

Postcode30625

CountryGermany

Phone number (incl. country code)495115350203

Alternative phone number

Fax number (incl. country code)495115350155

Email address christina.ziemann@item.fraunhofer.de

Public Enquiries

Title Dr

Last name Ziemann

First name Christina

Address line 1Nikolai-Fuchs-Str. 1

Address line 2

Address line 3

CityHannover

Postcode30625

CountryGermany

Phone number (incl. country code)495115350203

Alternative phone number

Fax number (incl. country code)495115350203

Email address christina.ziemann@item.fraunhofer.de

11. Scope of the study

What is the scope of the study?

Risk assessment

Optimization of in vitro mutagenicity/genotoxicity assays for prediction of in vivo mutagenicity and cancerogenicity of nitrosamines

Primary scope : Optimization of in vitro mutagenicity/genotoxicity assays for prediction of in vivo mutagenicity and cancerogenicity of nitrosamines

12. Main objective(s)

What is the main objective of the study?

Generating a better understanding on how the Ames test and the in vitro Comet assay can be methodologically optimized to reliably detect mutagenicity of different nitrosamines (NAs) and API-derived nitroso compounds.

Are there primary outcomes?Yes

Experimental data on mutagenicity of nitrosamines and API-derived nitroso compounds in the Ames test under different conditions, experimental Comet assay data on induction of DNA damage by these compounds using in vitro liver cell models and data on solubility, purity and on metabolic competence of S9 fractions and cell models.

Are there secondary outcomes?No

13. Study design

What is the design of the study?

In vitro compound mutagenicity study using the Ames test and the alkaline Comet assay

14. Follow-up of patients

Will patients be followed up?Not applicable/no follow-up

15. Data analysis plan

Please provide a brief summary of the analysis method

A carefully selected set of reference NAs, active pharmaceutical ingredient (API)-derived NAs and supporting reference compounds will be used to finally evaluate reproducibility, sensitivity (the proportion of genotoxic carcinogens that generate positive results), and specificity (the proportion of non-genotoxic compounds that generate a negative result) of each test model and provide data to estimate and compare the genotoxic potency of test compounds in the two different in vitro assays. The study will be complemented by a small Comet assay round robin study with HepG2 cells to demonstrate reproducibility.