Two drug therapies that could cure all forms of tuberculosis
Two new drug therapies may be able to cure all forms of tuberculosis, even the ones most difficult to treat (New Scientist, 2017).
TB Alliance is coordinating trials of the two treatments. The organisation’s president, Mel Spigelman, said “We will have something to offer every single patient. We are on the brink of turning TB around.”
At the moment it takes six months of drug treatment to cure ordinary TB, and two years to cure people whose infections are resistant to drugs. People with TB may need to take up to twenty tablets a day, plus injections.
Together the new treatments, called BPaMZ and BPaL, could make treating TB much simpler and more effective. BPaMZ involves taking four drugs once a day. Trials carried out in two hundred and forty people across ten countries in Africa suggest that it cures almost all cases of ordinary TB in four months, and most people with drug-resistant TB in about six months. In the majority of cases, the TB bacterium had disappeared from sputum within two months. Mel Spigelman said “The alliance has never before seen such rapid action against TB bacteria.”
Meanwhile, BPaL, a therapy that involves taking three drugs once a day, has so far cured forty of sixty nine patients with “extremely-drug-resistant TB” – the most difficult form to treat. What’s more, it achieved this within six months. The twenty nine remaining participants in this trial are still to be assessed.
The TB Alliance said BPaMZ has the potential to treat 99% of people who catch TB, while BPaL could treat the remainder.
Researchers presented results from both sets of trials at the Conference on Retroviruses and Opportunistic Infections in Seattle this week.
Mel Spigelman said the arrival of new drugs is long-awaited, because the existing treatment for TB is now fifty years old. According to the latest figures from the World Health Organisation, there were 10.4 million new cases of TB in 2015. Only 20% of people with resistant TB were treated, and of those only half were cured.
Once mass produced, BPaMZ could cost just a tenth of the $3,000 it now costs to treat drug-resistant TB.
Mel Spigelman said larger trials are needed to confirm the effectiveness of both therapies and for them to be approved for global use. At best, this would take at least three years for BPaMZ, although the therapy for extremely-drug-resistant TB may be available sooner.
David Moore, from the London School of Hygiene and Tropical Medicine, said “The results are exciting and encouraging, but we must be cautious saying we can treat everyone with these regimes. These are only preliminary data, so there’s a danger of jumping the gun.”