Tekmira's RNAi antivirals protect animals from lethal doses of Ebola, Marburg

Canada's Tekmira Pharmaceuticals ($TKMR) has unveiled new data showing that its antiviral RNA interference therapeutics were effective at abolishing Ebola and Marburg viruses in preclinical studies when treatment was delayed.

In a study of the company's TKM-Ebola drug, which is being developed under a contract with the U.S. Department of Defense, 83% of nonhuman primates survived when treated 24 or 48 hours after being infected with a lethal dose of the Ebola virus. When treatment was delayed to 72 hours after infection, the drug showed a 67% survival rate. Meanwhile, no animals treated with a placebo survived.

In nonhuman primates infected with a lethal quantity of Marburg virus--which belongs to the same family of hemorrhagic fever viruses as Ebola--Tekmira's TKM-Marburg achieved 100% survival when the drug was administered 48 hours after infection.

"These recent studies with TKM-Ebola and TKM-Marburg demonstrate survival in nonhuman primates despite delayed treatment after infection with lethal doses of the Ebola and Marburg viruses," Tekmira President and CEO Dr. Mark Murray said in a statement.

RNA interference (RNAi) therapeutics like Tekmira's work by "silencing" disease-causing genes. The use of RNAi therapeutics is currently limited because the newly introduced genetic material is difficult to deliver. Tekmira's lipid nanoparticle delivery technology platform is designed to capture and systemically deliver different nucleic acid molecules, such as small interfering RNA.

Tekmira says it expects to complete preclinical, chemistry, manufacturing and control studies as well as a submission to the FDA by the end of the year. The company hopes to launch a Phase I trial for TKM-Ebola in the first quarter of 2014.

- see the press release