In a new study, scientists have found that though a shortened 4 month treatment for TB could work well in subsets of TB patients, but could not taken as a substitute for current 6 month standard treatment.
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.
A clinical drug trial conducted in five Sub-Sahara African countries found the new treatment to be safe that cleared the lungs from TB bacteria rapidly, but a proportion of patients relapsed within months after treatment ended. The 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. Therefore, the regimen could not be recommended to replace the current treatment, though the difference in effectiveness between the two treatments varied considerably across the different countries where the study took place.
The study enrolled over 1,800 patients, where half of the patients received the standard six month treatment (rifampicin, isoniazid, pyrazinamide and ethambutol); the other half received the four month treatment with gatifloxacin replacing ethambutol.
This was a large study with 1,356 patients from five countries (Benin, Guinea Conakry, Kenya, Senegal and South Africa), noted the trial statistician Dr Katherine Fielding from the London School of Hygiene and Tropical Medicine. Additional analyses of their data and combining data from other trials would be essential to continue the search for new and improved TB treatments.
The results of the study are published in the New England Journal of Medicine.