New drug regimen could help save millions of lives

Better treatments for TB that can be used in patients with HIV are in great demand worldwide because millions of people have both diseases, complicating their treatment and putting them at high risk of death. About one-fifth of the 1.6 million people who died with HIV or AIDS in 2012 were killed by TB.

On Monday, representatives of the Global TB Alliance said a new drug regimen, known as PaMZ, was the first that could treat both drug-sensitive and multi-drug-resistant TB while remaining compatible with anti-retroviral treatments for HIV.

Senior medical officer with the alliance Daniel Everitt said a phase-two trial of the drug regimen in about 200 African patients over eight weeks showed it cleared TB bacterium in the sputum of 71 per cent of people who received it, compared with 38 per cent of those in a control group who received standard TB treatment.

About 40 of the 200 patients had HIV and continued their anti-retroviral treatment without any negative consequences. This was exciting, he said, because one of the key drugs used to treat TB complicates HIV treatment, creating the need for more medical attention and changes to medication.

Dr Everitt told the 20th International AIDS Conference in Melbourne that aside from being compatible with HIV medication, it was hoped PaMZ would reduce the number of pills and injections used to treat TB, curing people in a simpler, faster and more affordable way.

At the moment, he said patients with drug-sensitive TB generally received a cocktail of daily pills for about six months, leading to a cure rate of about 90 per cent to 95 per cent. Patients with multi-drug-resistant TB endure daily injections and pills for about two years, with a 60 per cent cure rate.

"We're aiming to get treatment up to 90 plus per cent cure," he said.

Dr Everitt said he also hoped the new drug regimen would prevent people acquiring multi-drug-resistant TB, a growing problem particularly in the Asia-Pacific region.

"A lot of the reason we have drug resistance is because of the complexity of treating regular drug-sensitive TB patients. People take the medication for a while but they stop when they feel better and then they don't come back for six months and then they're fine for a month or two and then it comes back as multi-drug-resistant TB and they need two years of treatment. So, to get simpler, shorter, better drug therapies for drug-sensitive TB will, hopefully, prevent drug resistance later on," he said.

A phase-three trial of PaMZ is about to begin, involving 1500 patients in 15 countries. If it is successful, Dr Everitt said the drug regimen may be available, hopefully in a single daily pill, by 2018. He said new treatments would not only extend the lives of the estimated 12 million people suffering from an active TB infection but would also help limit its spread.

"Every person treated prevents the spread,'' he said. "Typically, one patient coughing with pulmonary TB will infect 20 other people."

Meanwhile, a panel of leading HIV researchers said they were hopeful of finding a cure for HIV, which affects more than 38 million people, but said strategies to achieve "long-term remission" were more likely to be found first.

On Monday, seven of the world's top HIV scientists, including International AIDS Society President Francoise Barre-Sinoussi who discovered HIV, said they did not want to raise false hopes of a cure but believed remission was achievable.

Remission, which is also known as a ''functional cure", means someone can still have detectable HIV in their body but the virus is not active enough to require treatment.

Professor Barre-Sinoussi said a group of 14 French patients who received treatment very early in the course of their infection had already demonstrated this phenomenon, with some of them living for more than 10 years without the need for treatment.

''There is no reason not to be optimistic,'' she said.