For the first time in nearly half a century, the world may be on the verge of adding a new drug to its arsenal against tuberculosis (TB) – one that would not only drastically improve the treatment of TB and its multidrug-resistant strains, but also shorten it.
Adding a new drug, TMC207 to standard multidrug-resistant TB (MDR-TB) treatment regimens dramatically cuts the period from when patients start treatment to their sputum testing negative for TB, according to a study published in the June issue of the New England Journal of Medicine, in the US. The drug is being developed by pharmaceutical research company, Tibotec.
After two months, almost 50 percent of MDR-TB patients on the drug had sputum samples that tested negative for TB, compared to about 10 percent of the study's placebo group. The new antibiotic, TMC207, targets the bacteria's energy-producing enzyme, killing it off.
As a bonus, the drug has proven relatively easy to stomach in more ways than one, with potential dosing as low as three times a week – a factor that bodes well for treatment adherence.
"Currently, TB requires six months of treatment ... if strains become resistant to first-line drugs, patients require the use of second-line drugs, which are expensive and require two years of treatment, usually," said the study's co-author, Dr Alexander Pym, chief special scientist at the TB research unit of the South African Medical Research Council (MRC).
|New drugs are exciting, especially for people with drug-resistant TB but South Africa [still] needs to fix its TB and HIV health care provision|
"As a complete new class of antibiotic, it can be active against both TB and MRD-TB; the bugs have never seen [this drug] before; they haven't had opportunities to develop resistance."
But it remains to be seen whether it is a complete cure, what other drugs it must be combined with and whether it is completely safe.
TMC207 can also be stored at room temperature, cutting out the need for the costly refrigeration systems that are sometimes unavailable in developing countries, which bear the brunt of the world's TB burden.
Dr David Clark, CEO of the Aurum Institute, an independent health research institute in Johannesburg, South Africa, said the study - and the drug technologies produced by it - represented a breakthrough in TB treatment. The Aurum Institute runs one of the largest studies in TB preventative treatment in South Africa.
In 2007, an estimated 500,000 people globally were diagnosed with MDR-TB, but less than one percent received sufficient treatment, according to the latest Global TB Control report by the World Health Organization.
Although 13 percent of patients in the trial were HIV-positive, those on antiretroviral (ARV) treatment were excluded from this phase to allow doctors to isolate TMC207's effects without possible drug interactions between it and ARVs. However, the MRC's Pym said studies to look at the effectiveness of TMC207 in patients on ARVs were in the pipeline.
Dr Francois Venter, of the South African HIV Clinicians Society, told IRIN/PlusNews that despite the good news, TB remained a multifaceted problem:
"New drugs are exciting, especially for people with drug-resistant TB, but South Africa ... [still] needs to fix its TB and HIV health care provision."