Worldwide, tuberculosis (TB) remains one of the most important communicable diseases in terms of morbidity and mortality. Its control requires multi-drug therapy for at least six months and this tends to lead to patient non-compliance, and thus failure of therapy and ultimately emergence of drug resistance. Anti-TB therapy, given in the form of fixed-dose combinations (FDCs) reduces the number of tablets to be consumed and thereby increases patient compliance with recommended treatment regimens. Thus, FDCs play a significant role in preventing the emergence of drug resistance. However, the quality of FDCs and their registration requirements are major hurdles to their implementation in national programmes. There is also concern about the bioavailability of rifampicin.
To increase use of FDCs, their quality and registration needs to be addressed systematically. It is anticipated that a large global market for FDCs will encourage large-scale production and increased competition, which in turn will result in FDCs at affordable prices. The ‘Global TB Drug Facility’, established by WHO and its Stop TB partners, aims to ensure universal uninterrupted access to quality TB drugs for implementation of directly observed treatment short-course (DOTS) in resource-poor countries. In this programme, four-drug FDCs were accepted as the drugs of first choice because of their obvious advantages in controlling TB.
Current knowledge on anti-TB FDCs, their dosage, combinations, available clinical studies and the experiences with TB therapy should serve as lessons for selection of appropriate FDCs for other diseases such as malaria and AIDS.