Genetic polymorphisms and adverse reactions to antituberculosis therapy

Abstract

Tuberculosis is the leading cause of death from a single infectious agent globally, with the highest burden in low-and middle-income countries. Successful treatment requires prolonged administration of multiple drugs. The increasing threat of multidrug-resistant tuberculosis has prompted the development of a robust pipeline for new drugs. While generally safe and well tolerated, adverse drug reactions (ADRs) to TB drugs have a considerable impact on treatment outcomes. Pharmacogenetic testing has been implemented for some diseases to identify at-risk individuals and prevent ADRs. For tuberculosis treatment, the use of pharmacogenetic testing to optimize complex regimens and avoid ADRs is appealing, but there has been minimal implementation. To improve the use of pharmacogenetics, understanding both the pharmacology of relevant drugs and population-specific pathophysiology of ADRs are essential. This review highlights the major treatment-limiting ADRs with TB drugs, the current understanding of drug metabolic pathways, ADR pathophysiology, and known pharmacogenetic risk alleles. We highlight research gaps and barriers to meaningful clinical use and implementation of pharmacogenomic testing to prevent adverse reactions to TB drugs.

Keywords: HLA; NAT2; Tuberculosis; adverse drug reaction; genetic polymorphisms; isoniazid; pharmacogenomics; rifampicin.

Figure 1.

Major metabolic pathways and key metabolites of antituberculosis drugs.

Figure 2.

Immune-and nonimmune-mediated mechanisms of antituberculosis drug toxicity.