The 3T3 neutral red uptake phototoxicity test: Practical experience and implications for phototoxicity testing – The report of an ECVAM–EFPIA workshop

This is the report from the “ECVAM-EFPIA workshop on 3T3 NRU Phototoxicity Test: Practical Experience and Implications for Phototoxicity Testing”, jointly organized by ECVAM and EFPIA and held on the 25-27 October 2010 in Somma Lombardo, Italy. The European Centre for the Validation of Alternative Methods (ECVAM) was established in 1991 within the European Commission Joint Research, based on a Communication from the European Commission1. The main objective of ECVAM is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine and replace the use of laboratory animals. The European Federation of Pharmaceuticals Industries and Association (EFPIA) represent the pharmaceutical industry operating in Europe. Through its direct membership of 31 national associations and 40 leading pharmaceutical companies, EFPIA is the voice on the EU scene of 2,200 companies committed to researching, developing and bringing to patients new medicines that improve health and the quality of life around the world. The workshop, co-chaired by Joachim Kreysa (ECVAM) and Phil Wilcox (GSK, EFPIA) involved thirty-five experts from academia, regulatory authorities and industry that were invited to contribute with their experiences in the field. The main objectives of the workshop were: - to present 'in use' experience of the pharmaceutical industry with the 3T3 Neutral Red Uptake Phototoxicity Test (3T3 NRU-PT), - to discuss why it differs from the results in the original validation exercise, - to discuss technical issues and - consider ways to improve the usability of the 3T3 NRU-PT for (non-topical) pharmaceuticals, e.g. by modifying technical aspects of the assay or adjusting the criteria used to classify for a positive response. During the workshop, the assay methodology was reviewed by comparing the OECD Test Guideline with the actual protocol used, data from EFPIA and JPMA ‘surveys’ were presented and possible reasons for the outcomes were discussed. Experts from cosmetics and pharmaceutical industries presented their experience with the 3T3 NRU-PT and evidence was presented for phototoxic clinical symptoms that could be linked to certain relevant molecules. Brainstorming sessions discussed if the 3T3 NRU-PT needed to be improved and whether alternatives to the 3T3 NRU-PT exist. Finally, the view point from EU and US regulators was also presented. In the final session, the conclusions of the meeting were summarised with action points. It was concluded that the 3T3 NRU-PT is a hazard-based assay with a high level of sensitivity. It is relevant and an accepted test that correctly identifies non-phototoxic materials. However, positive results in the 3T3 NRU-PT often do not translate into a clinical phototoxicity risk. Possible ways to improve the practical use of this assay include: (i.) implementation of absorption criteria as a means to reduce the number of materials tested, (ii.) limit the highest concentration tested, and (iii.) consider modifying the criteria used to identify “positives” in the test.

CERIDONO Mara;  BAUER Daniel;  BARROSO Joao Felipe;  ALEPEE Natalie;  CORVI Raffaella;  DE SMEDT An;  FELLOWS Mick;  GIBBS Neil K;  HEISLER Eckhard;  JACOBS Abby;  JIROVA Dagmar;  JONES David;  KANDAROVA Helena;  KASPER Peter;  KINYAMU AKUNDA Jacqueline;  KRUL Cyrille;  LEARN Douglas;  LIEBSCH Manfred;  LYNCH Anthony;  MUSTER Wolfgang;  NAKAMURA Kazuichi;  NASH J Frank;  PFANNENBECKER Uwe;  PHILLIPS Gareth;  ROBLES Catherine;  ROGIERS Vera;  VAN DE WATER Femke;  WANDEL LIMINGA Ulla;  VOHR Hans-Werner;  WATTRELOS Olivier;  WOODS Julie;  ZUANG Valerie;  KREYSA Joachim;  WILCOX Phil; 

2014-01-15

ACADEMIC PRESS INC ELSEVIER SCIENCE

JRC67307

0273-2300,   

http://www.sciencedirect.com/science/article/pii/S0273230012001109,    https://publications.jrc.ec.europa.eu/repository/handle/JRC67307,   

10.1016/j.yrtph.2012.06.001,