MOSCOW, August 21 (RIA Novosti) - An experimental drug used against Marburg, a virus from the same filovirus family as Ebola, could be used to end the epidemic in West Africa, researchers say.
“This is the first study showing that we can treat [filovirus infections] when we first start seeing signs of illness,” Thomas Geisbert, a professor of microbiology and immunology at the University of Texas Medical Branch at Galveston, reports in the Science Translational Medicine journal.
Geisbert, who spent two decades at the US Army Medical Research Institute of Infectious Diseases working on treatments for emerging and lethal pathogens, tested a promising therapy for the Marburg virus on monkeys. All of the 16 animals infected with the most dangerous Marburg strain and later treated with the experimental drug survived, while none of the animals who were not treated did.
“I am very confident that the same will hold true with Ebola. We demonstrated in 2010 that the same strategy works against Ebola Zaire and I think we certainly can optimize the strategy to perhaps do even better,” Thomas Geisbert says.
During the 2010 tests on the Ebola Zaire virus strain, the animals were treated within an hour of being infected and survived. Geisbert now wants to see whether delaying treatment up to several days after infection will reduce the effectiveness of the drug. People who have contracted Ebola may not exhibit any symptoms in the first stages of the illness, so it is necessary to find a drug that would be equally effective both in immediate and delayed treatment.
Another experimental treatment for Ebola called ZMapp is being developed by Mapp Biopharmaceutical and San Diego-based LeafBio. The drug, created using tobacco plants, was tested on primates and then administered to two Ebola-infected US missionaries in Liberia, with positive results.
Unlike the drug in Geisbert’s study, which blocks the virus’ ability to reproduce, ZMapp prevents Ebola from entering cells.
ZMapp supplies were exhausted after the last doses were sent to Liberia, but its creators are now working with the US government to determine how quickly more can be produced.
Meanwhile Tekmira, a Canadian biotech company, has started testing the safety of the Ebola version of Geisbert’s therapy on humans. The US Food and Drug Administration requires human trials for all new drugs and vaccines, making exceptions only for the so-called exotic viruses like Ebola and Marburg. The agency accepts tests involving animals that replicate the human course of the disease, and safety trials in uninfected, healthy human volunteers.
There are currently no officially approved vaccines or drugs for the treatment of Ebola, which has claimed over 1,300 lives in West Africa since March.