A changing industry
Since the establishment of the European Pharmacopoeia in the 1960s, the world, and with it the pharmaceutical industry, has changed significantly. International harmonization among the three pharmacopoeias of Europe, Japan, and the United States (i.e., the three regions that started the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use [ICH]) was, therefore, a logical development. Harmonization activities among the European, Japanese, and US pharmacopoeias began in 1989 with the establishment of the Pharmacopoeial Discussion Group (PDG); an informal harmonization initiative between these pharmacopoeias parallel to ICH. In fact, it was a prerequisite for the ICH Steering Committee to agree on the elaboration of the ICH Guideline Q6A Specifications: Test Procedures and Acceptance Criteria for New Drug Substances and New Drug Products that the PDG committed to harmonizing the 11 general methods referred to in the document at that time and not to make unilateral changes once harmonization was complete. The ICH Q6A guideline includes a specific reference to the work of the PDG in chapter 2.8 “Pharmacopoeial Tests and Acceptance Criteria.”Where harmonization of general chapters is carried out, the aim is to arrive at interchangeable methods or requirements so that demonstration of compliance using a general chapter from one of the three pharmacopeias implies that the same result would be obtained using the general chapter of any of the other two PDG pharmacopeias. However, the activities of the PDG in harmonizing general methods have not been limited to the Q6A methods; a wide range of general methods (35) has since been added to the work program. These include methods, such as chromatography, that are crucial for the quality control of medicines and a prerequisite for further harmonization of specific monographs. Besides the harmonization of general methods, the PDG has also been working on monographs for widely used excipients. Currently, 62 such excipients are included in its work program. Clearly, the purpose of harmonizing a monograph is to arrive at identical requirements for all attributes of the product in question.
To date, 28 of the 35 general methods and 43 of the 62 excipient monographs have been harmonized. Detailed information on the work program of the PDG is published in Pharmeuropa and the respective forums of the other two PDG pharmacopeias. In addition, the Ph. Eur. contains a specific General Chapter 5.8., Pharmacopoeial harmonization, that provides more information on the outcome of harmonization. This chapter was revised by the Ph.Eur. Commission in November 2012 to provide further support to users by highlighting information on any nonharmonized attributes/provisions and on any local requirements (i.e., attributes that are present only in the Ph. Eur. text). Non-harmonized attributes/provisions are placed between black diamonds in the corresponding Ph. Eur. texts, and the local requirements are marked by white diamonds ().
The PDG has often been criticized of slow progress. However, it has to be acknowledged that the three pharmacopeias have differing legal statuses; the Japanese Pharmacopoeia is part of the Japanese government’s Ministry of Health, Labour and Welfare; the European Pharmacopoeia is part of the Council of Europe (an inter-governmental organization); while the US Pharmacopeia Convention (USP) is a private, not-for-profit organization that is independent of the US government. In addition, all three are embedded in their specific national/regional regulatory frameworks that, after more than 20 years of activity at the ICH level, are only partially harmonized.