The quality of the raw material is unfortunately a parameter that is rarely taken into account in granting export permits for generics if they are not licensed for sale on the domestic market, and rarely is this parameter considered important by international purchasers.
Equally, the method of drug synthesis is an important consideration which will enhance the quality of the drug. Pharmacopoeial monographs are based on the latest synthesis procedures where impurities, related substances and subproducts of degradation are well defined. A change in the method of synthesis must therefore be followed by a suitable adaptation to the process control, which is not always the case. The purchaser of generic drugs should be aware that conducting analyses which rely solely on pharmacopoeial monographs may not necessarily indicate the risk of toxicity from degradation products or impurities in the event that the method of synthesis has been changed (1).
The raw material market is extensive and a great choice of products is available worldwide. The following quality problems may be encountered when suppliers are located in different parts of the world:
• Geographical distance makes it difficult to locate or get information on the actual suppliers. The practice of using brokers or commercial intermediaries to facilitate administration and communication tends to break the bond between supplier-client. Additionally, a broker may be dealing with several manufacturers who are providing different components of one finished product.
• It may be difficult to locate the manufacturer of the raw material and obtain details of the synthesis procedure (profile of impurities and degradation products).
• Even when the manufacturer is known, distances make it both difficult and costly to audit.
• Production may be held up if suppliers are changed, if a source is suddenly cut or if the raw material is of a different standard and requires adjustments to the product formula.
Greater vigilance is therefore needed to assure quality when suppliers are situated at great distances. None the less, some countries have good systems and testing facilities in place.