An experimental Ebola virus treatment may be saving a U.S. patient's life in the days since his homecoming, after contracting the disease while working in Africa. Nearly 750 people have died due to the virus, including more than 50 aid workers, in areas including Liberia and Sierra Leone.

There's still no cure for Ebola, medical experts say, but experimental treatments are helping some patients fight the infection.

"If the situation continues to deteriorate, the consequences can be catastrophic in terms of lost lives, but also severe socioeconomic disruption and a high risk of spread to other countries," Dr. Margaret Chan of the World Health Organization said on Friday, according to theatlantic.com.

Dr. Kent Brantly may be among the first people who contracted Ebola in this recent outbreak to benefit from a secret drug. "Brantly had been working for the Christian aid organization Samaritan's Purse as medical director of the Ebola Consolidation Case Management Center in Monrovia, Liberia. The group yesterday confirmed that he received a dose of an experimental serum before leaving the country," theatlantic.com reported.  

He was seen walking from an air ambulance over the weekend after being flown to Emory University, where he's continuing to recover.

The serum that has saved Brantly's life is explained his way by the website: "The "top-secret serum" is a monoclonal antibody. Administration of monoclonal antibodies is an increasingly common but time-tested approach to eradicating interlopers in the human body. In a basic monoclonal antibody paradigm, scientists infect an animal (in this case mice) with a disease, the mice mount an immune response (antibodies to fight the disease), and then the scientists harvest those antibodies and give them to infected humans. It's an especially promising area in cancer treatment research."

The report goes further to say that the treatment isn't legal to use yet, but given the extreme circumstances, a blending of three monoclonal antibodies, called ZMapp, was used. The treatment was used under what CNN's Sanjay Gupta called the "compassionate use exemption." 

As CNN explained: "The medicine is a three-mouse monoclonal antibody, meaning that mice were exposed to fragments of the Ebola virus and then the antibodies generated within the mice's blood were harvested to create the medicine. It works by preventing the virus from entering and infecting new cells."

Nancy Writebol, the other missionary infected with Ebola "also received a vial of the medication, reported CNN. "Her response was not as remarkable, according to sources familiar with the treatment. However, doctors on Sunday administered Writebol a second dose of the medication, which resulted in significant improvement. She was stable enough to be evacuated back to the United States and is expected to arrive before noon Tuesday."

The two U.S. victims received approval to use the experimental medication within a week to 10 days of making the plea to the U.S. Food and Drug Administration. 

"This is the biggest and most complex Ebola outbreak in history," CDC director Dr. Tom Frieden said in a statement this week. "Far too many lives have been lost already."