New York, Oct 24 (IANS): There is bad news for patients suffering from tuberculosis (TB) as researchers have found that a shortened (four months) treatment could not be considered as an alternative to the current six-month standard treatment.

While the shortened treatment regimen was found to be effective for some, some of the patients suffered relapse within months after the treatment ended.

"Unfortunately, the results do not support a much-needed shortened TB regimen," study co-author Piero Olliaro, head of TDR's (Special Programme for Research and Training in Tropical Diseases) intervention and implementation research at World Health Organization.

TB remains a significant public health problem worldwide. There were an estimated 8.6 million people who developed TB and 1.3 million died from the disease in 2012.

The study was designed to verify whether replacing one of the four drugs of the standard regimen with gatifloxacin could shorten the overall treatment duration of TB from six to four months.

The study enrolled over 1,800 patients in five African countries of Benin, Guinea Conakry, Kenya, Senegal and South Africa.

Half of the patients received the standard six-month treatment of rifampicin, isoniazid, pyrazinamide and ethambutol. The other half received the shortened four-month treatment with gatifloxacin replacing ethambutol.

The new treatment was found to be safe and cleared the lungs from TB bacteria rapidly, but a proportion of patients relapsed within months after treatment ended.

The shortened treatment appeared beneficial to patients with no TB cavitation in their lungs, undernourished patients, and people living with HIV, but it was less effective among other groups.

"The standard treatment is very effective if taken for the full six months," Christian Lienhardt from WHO pointed out.

The results of the study were published in the New England Journal of Medicine.