After several decades without any notable progress, there are encouraging results in research and development of anti-TB drugs, the result of a large number of projects now in competition. Along with developing new drugs to treat
tuberculosis (
TMC207, SQ109,
LL3858) are being reassessed others to optimize their effectiveness in order to shorten and simplify
therapy (
rifampin and
rifapentine) and three other drugs, currently used for other indications, were forwarded towards TB (
gatifloxacin and
moxifloxacin,
linezolid). Time to approval as a antiTB
drug is 10-15 years, consisting of phases of preclinical and clinical research. Substitution of
moxifloxacin for
isoniazid during intensive phase treatment of
pulmonary tuberculosis resulted in a small but statistically nonsignificant increase in 8th- week culture negativity.
TMC207, a
diarylquinoline with a unique way to address Mycobacterial
ATP synthetase, shows high activity in vitro against Mycobacterial strains sensitive or resistant to all drugs in the first and second line, including
fluoroquinolones, demonstrating exceptional qualities in vivo against several species of mycobacteria, in various animal models.
TMC207 was added to a basic standard regimen in a study of MDR-TB patients. After two months and satisfactory tolerability, sputum conversion rate in culture was 48% (versus 9% in the placebo group). Two
nitroimidazole (PA-824 and OPC-67683) are currently in clinical development.
PA-824 demonstrated good safety and tolerability in adult patients with pulmonary TB in South Africa, when given once daily for 7 days. Associating
isoniazid, would prevent the selection of mutants resistant to
Isoniazid.
Linezolid 600 mg is currently being tested in a Phase II for treatment of
XDR-TB in the Republic of Korea.
PNU-100480, analogous to the previous one, has the potential to significantly shorten the treatment in cases where there is sensitivity and in those with resistance to drugs. 300 mg dose is under investigation in a phase II pilot study in MDR-TB in South Africa. With this interest and commitment, it appears that there is a chance of having a new
drug available soon.