By Natalie Grover
Aug 8 (Reuters) - Investors are showering attention on drug developers working on a potential treatment for the Ebola virus, even if some of the drugs are a long way from production.
The World Health Organization has declared the West African epidemic a public health emergency, reviving interest in antiviral drugs that could treat Ebola.
Companies such as Tekmira Pharmaceutical Corp , BioCryst Pharmaceuticals Inc and NanoViricides Inc have drugs that are still in pre-clinical trials, meaning they are yet to be tested in humans.
Sarepta Therapeutics Inc undertook some human trials on its drug, but lost government funding two years ago.
U.S. health regulators on Thursday allowed Canadian drugmaker Tekmira to test a drug in people infected with Ebola, relaxing its stance after blocking human tests last month.
Tekmira's stock jumped 40 percent on Friday, while BioCryst rose 12 percent. Sarepta was up 5 percent and NanoViricides rose 6 percent.
The severity of the current outbreak in Africa, in which around 1,000 people have died, has forced governments to expedite research funding and speed up approvals. Stockpiling drugs could also be a possibility as the virus spreads.
While these companies have other drugs that are closer to being approved, the spotlight for now is on their potential Ebola treatments.
BioCryst's BCX4430 drug is in pre-clinical trials to treat Marburg, a hemorrhagic fever virus like Ebola, and analysts said it may be a potential treatment for Ebola.
"This (drug's) broad-spectrum potential could be an appealing option for governments as BCX4430 offers the potential of a single drug for multiple viruses (including Ebola)," JP Morgan analyst Cory Kasimov said in a note.
Sarepta may be able to get back funding to test its anti-Ebola drug, which the U.S. Department of Defense withdrew in 2012, said Robert W. Baird & Co analyst Brian Skorney.
"I think the probability is that funding will rematerialize for the program, given that the WHO elevated Ebola to a critical threat today," Skorney told Reuters.
NanoViricides said on Monday it would restart development of its drug to combat Ebola.
Two other treatments have shown particular promise in monkeys. The first, produced by Mapp Biopharmaceutical Inc, gained prominence when it was given to two U.S. aid workers who contracted Ebola and have since shown signs of improvement.
The other, an intramuscular injection, from privately held Profectus BioSciences, was found to protect all the rhesus monkeys exposed to Ebola three weeks later.
Tekmira is one of a few companies with a treatment advanced enough to be tested on people. But the U.S. Food and Drug Administration halted clinical trials in July due to safety concerns.
Tekmira's shares rose 38 percent to C$21.55. BioCryst's stock was up 11 percent at $14.30. NanoViricides was up 7 percent at $4.26, while Sarepta was up 5 percent at $20.83. (Editing by Savio D'Souza)
Our Standards: The Thomson Reuters Trust Principles.