LONDON: Scientists have successfully tested a new tuberculosis treatment that has the potential to check an epidemic of a deadly, drug-resistant strain of the disease that has been threatening to sweep the globe.

Results from a groundbreaking trial of three drugs given in combination — one of them completely new and one not yet licensed for this use — killed more than 99 per cent of patients’ TB bacteria after two weeks of treatment. Currently people with TB must take drugs daily for six months and up to two years if they have a drug-resistant strain.

The trial was carried out in 85 patients in two centres in Africa. A larger trial, using the drugs for two months rather than two weeks, is now underway, but scientists are already excited by the early findings. The disease has been spreading on the back of the HIV epidemic — it is the leading cause of death of people whose immune systems have been weakened by the HIV virus in developing countries.

Remarkably, the new drug combination appears to be equally effective on drug-resistant TB — strains of the disease now spreading around the world which are susceptible to few of the established antibiotics used for TB. Such cases can take years to treat and are extremely expensive.

“The implications of this trial are huge,” said Dr Mel Spigelman, chief executive of TB Alliance, a non-profit organisation dedicated to the hunt for new TB drugs.

It was the first time that more than one unapproved drug had been tested at a time, he said, which could prove to be a more successful strategy for the future than trialling one drug at a time.

“People with drug-susceptible and drug-resistant TB could be cured in as little as four months or even shorter,” he said. In the case of multi-drug-resistant TB, “we could be reducing their treatment by one to two years or more. The regimen also promises to be in the order of 90% cheaper than the current MDR treatment regimen.”

If the new combination turns out to be as effective as scientists hope, doctors would be able to treat all patients with it no matter what sort of TB they have, said the study's lead author, Dr Andreas Diacon, of Stellenbosch University, Cape Town, South Africa.

“Treating drug-sensitive and drug-resistant TB with the same regimen can simplify the delivery of TB treatment worldwide.”

The new combination is also safe to use with patients on HIV treatment, unlike some existing TB drugs.  The results of the study were presented at the International Aids Conference in Washington and published in the Lancet medical journal, which also ran a commentary by Dr Giovanni Battista Migliori of the World Health Organisation Collaborating Centre for Tuberculosis and Lung Diseases.

While Migliori said the study's results were very promising, he warned that new drug regimens would need to be used carefully if healthcare providers were to avoid repeating the mistakes of the past and allowing resistance to develop.

“The international community has the chance to prevent the misuse of new drugs and regimens,” he wrote. “To protect the investment in these drugs, the rational use of antibiotics within strengthened health systems is necessary to avoid the real risk of losing these new agents in a time shorter than that needed to develop them.”

By arrangement with the Guardian

By Sarah Boseley