Current treatment for drug-resistant tuberculosis (DR-TB) involves going through a punishing two-year regimen, taking up to 20 tablets daily in addition to months of daily painful injections. Side-effects of the treatment can include permanent hearing loss, with some developing suicidal depression and psychosis, and even after all that, only around half of patients with multi-drug resistant tuberculosis (MDR-TB), and only one quarter suffering with extensively drug resistant TB (XDR-TB) will be cured.
Now, new recommendations from the World Health Organization (WHO) have the goal of faster detection and improved treatment outcomes for MDR-TB through use of a novel rapid diagnostic test and a shorter, cheaper treatment regimen.
This alternative, at least for adults and children who are eligible, opens the door to a more easily tolerated, shorter regimen with better chances for successful cure. These shorter treatments will also enable national TB programs to widen access to more effective treatment, resulting in hopefully lowering rates of disease transmission.
“This is a critical step forward in tackling the MDR-TB public health crisis,” said Dr Mario Raviglione, Director of WHO’s Global TB Programme. “The new WHO recommendations offer hope to hundreds of thousands of MDR-TB patients who can now benefit from a test that quickly identifies eligibility for the shorter regimen, and then complete treatment in half the time and at nearly half the cost.”
The shorter treatment regimen also costs significantly less - at just under $1,000 per patient in developing countries, said Raviglione.
The shorter regimen is recommended for patients diagnosed with uncomplicated MDR-TB, for example those individuals whose MDR-TB is not resistant to the most important drugs used to treat MDR-TB (fluoroquinolones and injectables), known as “second-line drugs”. It is also recommended for individuals who have not yet been treated with second line drugs.
The WHO is encouraging researchers to finish ongoing research, so that the evidence base for use of this regimen can be strengthened.
Multidrug-resistant TB (MDR-TB) is caused by TB bacteria that are resistant to at least isoniazid and rifampicin, the two most effective TB drugs. Based on figures from 2014, the latest year for which data are available, WHO estimates that 5% of TB cases are multidrug-resistant.
This translates into 480,000 cases and 190,000 deaths each year.
Extensively drug-resistant TB (XDR-TB) is a form of MDR-TB that is also resistant to any fluoroquinolone and any of the second–line anti-TB injectable agents (i.e. amikacin, kanamycin or capreomycin). About 9% of MDR-TB patients develop XDR-TB, which is even more difficult to treat.
The WHO End TB Strategy, adopted by all WHO Member States, acts as the roadmap for countries to reduce TB incidence by 80% and TB deaths by 90%, and to eliminate catastrophic costs for TB-affected households by 2030.
Image: Courtesy McGill University