29 July 2015

The ICH Expert Working Group (EWG) responsible for the maintenance of the Q3C Guideline has revised the Permitted Daily Exposure (PDE) for Methyl isobutyl ketone (MIBK) which was listed in ICH Q3C(R5) as a Class 3 solvent (“solvents with low toxic potential”). New carcinogenicity data with MIBK are now available and suggest that MIBK is carcinogenic in rats and mice. Based on this new information, the EWG is recommending that MIBK is moved from the Class 3 category, to the Class 2 category for “solvents with inherent toxicity” which should be limited in pharmaceutical products. In addition, it is proposed to include Triethylamine as a new Class 3 solvent.

The draft Q3C(R6) document is available for download on the Quality Guideline page. You are invited to provide comments on the draft Q3C(R6) document by e-mailing the ICH Secretariat. More details under the Open Consultation page.

Note that stakeholders from EU, USA, Japan, Canada and Switzerland are encouraged to submit their comments to their respective Regulatory Authorities.

For more information about the Q3C maintenance process see the ICH Process of Harmonisation page under about us on the ICH website.