Researchers say they have made a major breakthrough in treating tuberculosis.

Results of an international study show a new combination of drugs means that drug-resistant TB can be cured in as little as four months, instead of two years.

The drug combination, known as PaMZ, killed more bacteria than standard treatment and was effective in treating drug-resistant TB.

"This shows its potential to shorten therapy ... for drug-sensitive and some forms of multi-drug-resistant TB," said Dr Mel Spigelman, chief executive of the TB Alliance, which conducted the study.

The results have been released at the International AIDS conference in Melbourne. Around the world, TB remains the largest killer of people with AIDS.

"Seventy-one per cent of people treated with PaMZ were cleared of bacteria at the end of two months when evaluated with the most sensitive diagnostic methods available," the report authors found.

"Only 38 per cent of people treated with standard therapy were clear at eight weeks."

Researchers say the newer therapy can be delivered more cheaply, safely and simply than current standard therapy.

Epidemic on Australia's doorstep

TB remains a serious public health issue in Papua New Guinea. There are fears the country is on the brink of an epidemic.

Tuberculosis as seen under a microscope is the largest killer of people with AIDS around the world. ( www.wadsworth.org )

About 15,000 new cases of tuberculosis are recorded each year in PNG. The World Health Organisation says nearly a quarter of those cases prove fatal.

UNAIDS PNG coordinator Stuart Watson says cases of drug-resistant and extra-drug-resistant TB are increasing.

"We need to get control of this before we really have a completely runaway TB epidemic with greater drug resistance," he told ABC's Pacific Beat.

"TB is treatable, TB is something that is preventable, unlike HIV, so this is really quite a tragedy."

New way to tackle tuberculosis

PaMZ combines three drugs in one pill. This includes two candidate drugs not licensed for use against tuberculosis - PA-824 (Pa) and moxifloxacin (M), and one existing antibiotic used in TB treatment, pyrazinamide (Z).

Earlier study results show PaMZ's potential to treat both drug-sensitive and drug-resistant patients and to dramatically shorten treatment times for some patients.

Only just over half of all patients who start treatment for multi-resistant TB complete a full course because of the long duration of treatment, combined with the pain and side effects of current treatments.

Because of the latest results, a large phase three study will proceed with funding from the Bill and Melinda Gates Foundation.

Australia has also promised to support the development of new TB treatments as part of the Global Partnership for TB drugs.

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