Meet the Tiny Company Behind the Experimental Antibodies for Ebola

— -- The companies manufacturing an experimental drug treating two American Ebola patients aren't among the largest multinational pharmaceuticals in the world. In fact, leading the effort is a small nine-employee firm in San Diego.

Mapp Biopharmaceutical Inc., founded in 2003, says on its website that it develops "novel pharmaceuticals for the prevention and treatment of infectious diseases, focusing on unmet needs in global health and biodefense."

Mapp's commercialization arm is LeafBio Inc., which has no employees and just two owners, Mapp President Larry Zeitlin tells ABC News.

Mapp, along with LeafBio and Defyrus Inc. in Toronto, Canada, collaborated to create the trademarked ZMapp.

The three firms say in a statement that ZMapp has not yet been evaluated for safety in humans, but was first identified as a drug candidate in January 2014.

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"As such, very little of the drug is currently available," the three companies said in a statement on Monday. "Any decision to use an experimental drug in a patient would be a decision made by the treating physician under the regulatory guidelines of the FDA. Mapp and its partners are cooperating with appropriate government agencies to increase production as quickly as possible."

Defyrus could not be reached for comment.

According to USASpending.gov, Mapp has received nearly $7.5 million from the U.S. government in the form of eight federal grants since 2005, which is included in the more than $40 million it has received from the federal government overall.

Vaccines and treatments for rare diseases are very complicated to make and only a handful of the big players participate, according to Damien Conover, a pharmaceutical industry analyst with Morningstar who does not cover the three companies.

"Vaccines tend not to have the pricing power of other drugs, so there is little commercial benefit," he said. "Any new procedure that could bring down the cost or develop [a vaccine] more quickly would be very helpful."

According to Mapp’s website, its Ebola drug is a “cocktail” of monoclonal antibodies, which had been used in monkey studies.

“When administered one hour after infection, all animals survived,” a 2012 company statement reads. “Two-thirds of the animals were protected even when the treatment, known as MB-003, was administered 48 hours after infection.”

The death toll of the Ebola outbreak in Guinea, Liberia, Nigeria and Sierra Leone climbed to 887, according to the World Health Organization. In all, 1,603 people have been infected.

ABC News' Sidney Lupkin contributed to this report.