17. MDR-TB Subjects may have previously been treated for DS-TB with first-line TB drugs (isoniazid, rifampicin, ethambutol, pyrazinamide and/or streptomycin) and/or received ≤7 days MDR-TB treatment, provided that treatment is/was discontinued at least 7 days prior to randomization. It should be confirmed that the MDR-TB treatment can be safely stopped and the screening period is long enough to allow for a washout period of 5 times the longest half-life of the drugs.