(Reuters) - Mapp Biopharmaceutical Inc said on Thursday that the U.S. Food and Drug Administration granted fast track status to its Ebola drug ZMapp.

The FDA grants the status to drugs intended to treat serious conditions that have few or no treatment options and expedites the review of such drugs.

ZMapp, which also has an orphan drug status from the regulator, was first tested on humans during the Ebola virus outbreak in West Africa in 2014, but was not subjected to controlled trial to determine its potential.

The drug was given on an emergency basis initially to sick health workers evacuated from the region.

The Ebola epidemic is the largest in history, affecting multiple countries in West Africa, according to the Centers for Disease Control and Prevention.

Cases were reported in Liberia, Nigeria, Mali, Senegal, and has killed over 11,000 people since 2013.

Mapp Biopharma is based in San-Diego, California.