The European Medicine Agency publishes answers to frequently asked questions after they are discussed and agreed to by the GMP/GDP Inspectors Working Group. In April 2011 the Agency published the following statement:
"The Good Manufacturing Practice Basic Requirements for Active Substances used as Starting Materials (EU GMP guide Part II) only applies to the manufacture of sterile active substances up to the point immediately prior to the active substance being rendered sterile. The sterilisation and aseptic processing of sterile active substances are not covered by this guideline and shall be performed in accordance with GMP for medicinal products (Commission Directive 2003/94/EC; as interpreted in the Basic Requirements for Medicinal Products including annex 1 of the EU GMP guide Part I). This implies that for any active substance manufacturer who performs sterilisation and subsequent aseptic handling of the active substance, a valid manufacturing authorisation or GMP certificate from an EEA authority or from an authority of countries where MRA or other Community arrangements apply has to be submitted.
Also the active substance manufacturer has to submit data on the sterilisation process of the active substance (including validation data) to the Marketing Authorisation applicant/holder for inclusion in the dossier submitted for the finished product and approval by the licensing authority(ies)."
Source: EMA Website