To effectively treat patients diagnosed with drug-resistant (DR) tuberculosis (TB) and protect the population from further transmission of this infectious disease, an uninterrupted supply of quality-assured (QA), second-line anti-TB drugs (SLDs) is necessary. Patients diagnosed with multidrug-resistant tuberculosis (MDR TB)--a disease caused by strains of Mycobacterium tuberculosis (M.tb.) resistant to two primary TB drugs (isoniazid and rifampicin)--face...