Linezolid for the treatment of complicated drug-resistant tuberculosis: a systematic review and meta-analysis
The treatment of multi drug-resistant TB (MDR-TB) is complicated by the fact that most medicines have poorly established efficacy and are associated with a relatively high frequency of side effects. As a result, treatment success averages around 60%, and around 10% of patients default from treatment, and another 10% die while on treatment. Therefore, there is an urgent need to expand treatment options for patients with MDR-TB. A number of promising drugs are in development, but in addition there are a number of drugs used to treat other bacterial infections that show promise for MDR-TB. One such drug is linezolid. However, its use has been limited by the fact that the evidence base for linezolid use for treating MDR-TB is poor, and the drug is associated with severe side-effects.
In order to further explore the potential for using linezolid, MSF authors conducted a systematic review of the available evidence for its use in treating patients with MDR-TB. The review found 11 studies which overall reported a relatively high rate of treatment success for patients treated with linezolid as part of combination therapy (68% treatment success). There appeared to be no difference in treatment success comparing patients treatment with lower or higher doses. This is potentially important because lowering the dose may be a way to limit side effects.
Overall, this study concludes that linezolid appears to be a useful drug for the treatment of patients with complicated drug-resistant TB. However, price is a barrier: In South Africa, where linezolid is patent protected, linezolid costs approximately US$2500 per month of treatment. In contrast, a generic version is available in India for US$50–70/month.