Research finds a new way to treat tuberculosis with fewer tablets than today's recommended course of treatment.

The novel drug combination makes it easier for patients to complete their course of treatment so helping to overcome the growing problem of drug resistance, which occurs when patients are irregular at taking their medication.

In 2012, an estimated 8.6 million people globally developed TB and 1.3 million died from the disease. In the same year, there were around 9,000 cases in the UK and, of these, 3,500 cases in London alone.

Most cases of TB are curable if treated effectively and promptly. The standard treatment is four drugs daily for two months followed by two drugs daily for four months - around 420 tablets over a six-month period.

This research shows that a novel combination of the drugs rifapentine and moxifloxacin could reduce the number of tablets in a course of treatment by about a third. Trial participants took the drugs ethambutol, moxifloxacin (400 mg), rifampicin and pyrazinamide daily during the first two months of treatment and then rifapentine and moxifloxacin once a week during the last four months.

The results showed 97 percent of patients [180 out of 186] taking the six-month rifapentine and moxifloxacin combination were cured, which was similar to those taking the standard treatment [where 155 out of 163, or 95 percent of patients were cured]. Study participants were assessed 18 months after starting their treatment.

The clinical trial was led by St George's, University of London together with the Medical Research Council Clinical Trials Unit at UCL, working with researchers in Botswana, South Africa, Zambia and Zimbabwe.

Lead researcher Dr Amina Jindani, of the INTERTB Consortium at St George's, University of London, said: "The burden of taking tablets is huge for TB patients. Consequently, even with the best will in the world, patients sometimes stop their treatment once they begin to feel better. Over a long period of time this has led to more drug resistant strains and today's treatment is simply no longer adequate if we are to contain the disease.

"Less tablets means there is a higher chance of the patient completing their treatment. It also makes it easier for clinics to supervise treatment. This is particularly important for countries where clinics are severely under resourced and where it is not uncommon for patients to travel many miles to receive each treatment."

A total of 827 people with newly-diagnosed tuberculosis took part in the trial. The trial was designed to test whether new combinations of drugs could reduce how often patients have to take tablets in a six-month treatment, or reduce the length of treatment from six months to four months. However, the study showed that the combination of rifapentine and moxifloxacin after the first two months of treatment does not allow shortening of treatment from six to four months. Patients still need to take their treatment for six months, but the new once-weekly drug combination could make that easier.

The drug combination could also be used in patients with drug resistant strains because it doesn't contain isoniazid, the drug that patients are most likely to be resistant to.

The findings, which were funded by the European and Developing Countries Clinical Trials Partnership, are published in the New England Journal of Medicine.

The investigators point out that a number of considerations need further investigation before health services could prescribe the once-weekly treatment combination. These include the cost effectiveness of the proposed programme and more data on the effectiveness of the proposed regimen in HIV-positive patients, who are particularly at risk of TB.