Tuberculosis is a leading cause of morbidity and mortality worldwide. Current TB treatments are inadequate, requiring patients closely adhere to multi-drug regimens that are long, complex, and often poorly tolerated. These concerns are greatly magnified in rifampicin-resistant (RIF-R) TB, an urgent global and EU public health priority. WHO estimates that only 54% of patients who began RIF-R TB treatment in 2016 were cured. In addition to these well-recognized shortcomings, current TB treatments, particularly those for RIF-R TB, leave a majority of cured patients with permanent, clinically significant lung impairment and radiographic evidence of bronchiectasis and fibrosis. This project will determine if two adjunctive host-directed therapies (HDTs) can prevent these poor outcomes. 330 patients with RIF-R TB and baseline risk factors for poor outcome will be enrolled in a randomized, controlled, 3-armed multi-centre trial, with clinical sites in Romania, Moldova, Georgia, Mozambique, and South Africa. All patients will receive standard multidrug therapy according to national guidelines. Those patients randomized to the experimental arms will in addition receive either CC-11050 or metformin. These selected HDT candidates represent 2 complementary HDT strategies: reducing inflammation vs inducing host cell anti-microbial activity, respectively. Both candidates are supported by data from preclinical and clinical studies. Co-primary efficacy endpoints will examine effects on lung function (measured by spirometry) and infection (measured as time to stable sputum culture conversion). A sub-study will examine quantitative change in lung radiodensity by CT scan. If successful, this ground-breaking project will increase Europe’s capacity to control RIF-R-TB by developing new treatments that increase the likelihood of cure and reduce the risk of life-long disability.