Of all potential Ebola drugs, Brincidofovir is latest stage by far, so I think Chimerix might turn out to be a good Ebola play despite the ho-hum reaction by the market so far today.
Favipiravir (Toyama Chemical) was approved in Japan on March 2014 for influenza. The drug has broad spectrum activity against RNA viruses and there's approximately 20,000 doses available in Japanese inventory. In terms of U.S. clinical testing Favipiravir (influenza indication) may have a slight lead on Chimerix's Brincidofovir*. Favipiravir is potentially the best existing option for multiple strains of influenza and it will be studied in Ebola.
If you asked me in advance, I would not have predicted that brincidofovir would have inhibitory activity toward Ebola. Brincidofovir has been touted – and shown efficacy in humans – against DNA viruses.
But Ebola is not a DNA virus. Its genome is made of RNA and the virus uses a very different enzyme to make more copies to create more viruses.