sentences:  A 2018 meta-analysis of 12,030 patients from 25 countries in 50 studies has demonstrated that treatment success increases and mortality decreases when treatment includes bedaquiline, later generation fluoroquinolones, and linezolid.One regimen for XDR-TB called Nix-TB, a combination pretomanid, bedaquiline, and linezolid, has shown promise in early clinical trials.Successful outcomes depend on a number of factors including the extent of the drug resistance, the severity of the disease and whether the patient's immune system is compromised.