CHICAGO (AFP) - A NEW regime of antibiotic drugs appears to dramatically shorten the time needed to cure highly infectious and deadly tuberculosis (TB) from six months to just four, according to research unveiled at a medical conference on Tuesday.

A team of Brazilian and US TB experts reported at a meeting of the American Society for Microbiology that adding the drug moxifloxacin to a standard cocktail of antibiotics increased by 17 per cent the number of patients who cleared active TB infection from their lungs, from 68 to 85 per cent.

The drug mixture shortened by two months the time needed to cure the dreaded lung ailment which kills some 1.5 million people each year, mostly in developing countries, experts reported at a meeting of the 47th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC).

The new combination drug therapy uses moxifloxacin in the place of an older, more traditional anti-TB drug, ethambutol.

'This is the most compelling evidence in nearly 25 years that a novel antibiotic drug combination works better than the current gold standard at curing active TB infection,' said study senior author Richard Chaisson, a professor of medicine, epidemiology and international health at The Johns Hopkins University School of Medicine.

He noted nearly nine million new cases of TB are diagnosed each year in the world, and more than one-and-a-half million people die from the disease.

TB can be particularly lethal for those with HIV and Aids. The lung ailment has reached epidemic levels in developing countries with the high HIV infection rates.

In coordination with the conference, the Bill and Melinda Gates Foundation announced that it was donating US$280 million (S$422 million) to research on tuberculosis.

The Gates donation would be spread over five years through 11 separate grants covering TB vaccines, diagnostic tests, and medications.

The foundation said research on the highly infectious lung ailment is antiquated and urgently is need of updating, according to a press release.

The 80-year old TB vaccine rarely is effective after childhood, while TB drugs, which require long and cumbersome regimens, have been less effective over time as they become more drug-resistant.