April 2 (HealthDay News) -- Using a new antibiotic called moxifloxacin in combination with other drugs could cut several months off the six months it currently takes to cure patients with drug-treatable tuberculosis, according to a phase 2 study.

Long treatment times can result in patients failing to complete their drug therapy, so a shorter period of treatment could improve patient compliance, the researchers noted. Shorter TB treatment regimens would also reduce the workload for overburdened TB control programs, especially in countries with high TB rates.

The study included 170 TB patients treated at a hospital in Rio de Janeiro, Brazil, who were receiving a standard combination of three first-line TB drugs. They were randomly selected to receive as their fourth drug either moxifloxacin 400 milligrams, along with an ethambutol placebo (85 patients), or ethambutol (15-20 mg per kilogram of body weight) plus moxifloxacin placebo (85 patients) five days a week for eight weeks.

The drug ethambutol is widely used in TB treatment but has very little activity and was used as a control in this study.

After eight weeks, 80 percent of patients in the moxifloxacin group tested negative for TB, compared with 63 percent of patients in the ethambutol group. A total of 16 negative events (eight in each group) were reported in 12 patients, but only one of those events was linked to moxifloxacin, according to Dr. Richard E. Chaisson, of the Center for Tuberculosis Research at Johns Hopkins University School of Medicine in Baltimore, and colleagues.

The study is in the April 4 edition of The Lancet.

"The results of our trial have substantial implications for future trials. First, the improved culture conversion rate found after 8 weeks in the experimental group suggest that moxifloxacin, in combination with other first-line anti-tuberculosis drugs, could shorten the time needed to cure tuberculosis by several months," the research team wrote.

SOURCE: The Lancet, news release, April 2, 2009