Phase 2a Published Results Show the Potential of a New TB Regimen with Novel Drugs Bedaquiline and Pretomanid (PA-824)

Results of study testing BPaZ published in American Journal of Respiratory and Critical Care Medicine; Regimen now being tested in Phase 2b clinical trial

January 28, 2015

A promising new tuberculosis (TB) drug regimen, which could improve the treatment of drug sensitive TB and multi-drug resistant (MDR-) TB, was identified in a clinical trial assessing combinations of new and existing antibiotic drugs, according to research published today in the American Journal of Respiratory and Critical Care Medicine.

Based on the published results of the Phase 2a two-week trial and earlier studies, the BPaZ combination—comprising bedaquiline, a drug that is provisionally approved to treat MDR-TB; pretomanid (formerly PA-824), which is being tested in multiple clinical trials; and pyrazinamide, part of today’s first-line treatment—has been advanced to a two-month Phase 2b clinical trial, called NC-005, which began in 2014.

“This clinical trial shows the importance of testing combinations including new TB drugs, whether already approved or not, to determine the most effective regimens,” said Mel Spigelman, MD, President and CEO of TB Alliance, the sponsor of the study. “With limited resources for TB research, we need to ensure that we advance only the most promising potential new treatment regimens that will maximize the public health impact.”

According to the World Health Organization, TB killed 1.5 million people in 2013—one person every 21 seconds. Part of the challenge of overcoming TB is the difficulty of the treatment, which consists of medicine that must be taken for six months to 2 years.

The trial, called NC-003, took place in two locations in the Cape Town area of South Africa: the Task Clinical Research Centre in Bellville and the Centre for Tuberculosis Research Innovation at the University of Cape Town Lung Institute.

“TB is a huge problem in South Africa, with one out of every 100 persons newly diagnosed with the disease each year,” said Prof. Andreas Diacon, director of TASK Applied Science in South Africa and the lead author of the study. “This study’s results help pave the way for future study of a new treatment that will not only benefit South Africa, but people suffering from TB around the world.”

The 14-day Phase 2a study had seven treatment arms, out of which the BPaZ combination emerged as the most effective for a potential new TB treatment regimen. Specifically, the BPaZ regimen killed more than 99 percent of TB bacteria in patient’s sputum in two weeks, and appeared well tolerated and safe.

The trial also tested another drug, clofazimine, approved to treat leprosy but is sometimes used off-label to treat MDR-TB. However, it had no activity alone or in combinations with other drugs over the course of the two-week study.


About the TB Alliance

The Global Alliance for TB Drug Development (TB Alliance) is a not-for-profit organization dedicated to finding faster-acting and affordable drug regimens to fight tuberculosis (TB). Through innovative science and with partners around the globe, we aim to ensure equitable access to faster, better TB cures that will advance global health and prosperity. The TB Alliance operates with funding from Bill & Melinda Gates Foundation, European Commission, Global Health Innovative Technology Fund, Irish Aid, National Institute of Allergy and Infectious Disease, UNITAID, United Kingdom Department for International Development, United States Agency for International Development, and the United States Food and Drug Administration. For more information please visit