JOHANNESBURG--South Africa launched a new drug program to treat multidrug-resistant tuberculosis (TB) on Friday in a bid to combat the leading cause of natural deaths in Africa's most industrialized economy.

The Health Department said it will run a clinical research program for the drug Delamanid, made by Japan's Otsuka Holdings Co Ltd, involving 400 patients over the next two years.

"Resistance is very minimal to it. The added advantage of this drug is it is more tolerable," Health Minister Aaron Motsoaledi told a briefing for World TB Day in Johannesburg.

TB is a bacterial infection which kills more people each year in South Africa than any other infectious disease. It accounted for 7.2 percent of natural deaths in 2015, more than diabetes or HIV/AIDS.

Delamanid has already been used in the European Union, Japan and South Korea.

TB is normally treated with a combination of antibiotics. But extensive overuse of antibiotics worldwide has led to a rise in drug-resistant strains.

A report this week in The Lancet Respiratory Medicine, a scientific journal, said this threatened to derail the progress made in controlling TB worldwide.

In 2015 the World Health Organization estimated that 1.8 million people died globally due to TB, with South Africa among the top six countries that together account for 60 percent of deaths.

An estimated 480,000 people developed multidrug-resistant TB (MDR-TB) that year, according to the WHO.