The two-antibody cocktail developed at Canada's National Microbiology Laboratory was able to cure Ebola-infected monkeys, according a study published in Science Translational Medicine, a US journal.

The MIL77E cocktail was based on the three-antibody cocktail called ZMapp, which cured a number of foreign aid workers in West Africa during the latest and biggest Ebola outbreak, the article said.

It was because one antibody named 4G7 from ZMapp has been hard to produce and the yield is quite low compared to the other two mAbs the mew drug has two antibodies instead of three according to Xiangguo Qiu, the first author of the article, Xinhua reported.

"The two monoclonal antibodies (mAb) in the MIL77E cocktail are 13C6 and 2G4, which act similarly to the three mAb ZMapp treatment," Qiu said.

Another reason for reducing the number of antibodies is "the cost of treatment would be decreased if it worked," she said.

ZMapp was produced by U.S.-based Mapp Biopharmaceutical Inc., but two of its three components were originally developed at the National Microbiology Laboratory, and the third at the U.S. Army Medical Research Institute of Infectious Diseases.

In the new study, Qiu and colleagues produced 13C6 and 2G4 in modified Chinese hamster ovary cells and found that the two-antibody cocktail protected all three monkeys three days after infection with the Ebola virus.

However, a similar cocktail comprised of two ZMapp antibodies, which are produced in tobacco leaves instead of mammalian cells, protected only two of three monkeys.

"This finding is very exciting," Qiu said, given that ZMapp is only effective to Zaire Ebola, one of five species.

"It has the potential to include an additional monoclonal antibody against another Ebola virus strain, providing a broader coverage against outbreak strains," she said.

Currently, there are currently no licensed therapies against the Ebola virus.