The Guideline mentioned in the title aims to cover the EU Directive on the manufacture of medicinal products in more details and interpret it. This is one of the main reasons why the Guideline has been revised. In its last version from 1996, the Guideline referred to the former Directive which has now been replaced by Directive 2001/83/EC. Furthermore, since the creation of the Guideline in the 90's, further fundamental GMP papers have come into force, i.e. the ICH Q8-10 series, and the CTD format for marketing authorizations has been introduced. The ongoing revisions of the validation guidelines at the moment should also be taken into consideration in the revised Guideline.
The currently applicable version of the Guideline from 1996 can be found here and the concept paper on the revision of the Guideline here.
Once the revision is completed, a 6-month comment period will start. After a further 6 months, the Paper should be valid.