The next day, another surprise: Mukpo, being treated in Nebraska, would also receive brincidofovir.
"After looking at the data on this drug, collaborating with the CDC and FDA and speaking with the patient and his family, we decided this was currently our best option for treatment," Phil Smith, medical director of Nebraska Medical Center's Biocontainment Unit, said in a statement. "Every patient is somewhat different, and we believe brincidofovir is the best choice."
Chimerix again rose. Tekmira again dropped—many were presumably counting on Nebraska to again draw upon TKM-Ebola, especially as Mukpo was in more stable condition than Duncan.
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Then on Wednesday, Texas Presbyterian released the news that Duncan had passed away. Questions swirled—and continue to—about his treatment, the delay in care he received at the hospital, and, of course, the implications for brincidofovir's efficacy against Ebola.
"Chimerix shares are likely to be (awkwardly) tracking the fate of the Ebola outbreak and treated patients," Piper's Schimmer wrote in a research note. "Ultimately, the utility of brin for treating Ebola and other diseases will be defined by animal models and potentially larger human clinical trials, as opposed to n=1 experiences."
In other words, still not enough is understood about the way Chimerix's drug works in people to conclude whether it works for Ebola. Because of its demonstrated safety profile, and the fact that it's a pill (which is easier to manufacture than a large molecule biologic, like ZMapp; or TKM-Ebola, which uses a technology called RNA interference) and can be stored at room temperature, hopes are high. But there is still more work to do before this drug, and any of the others—including Tekmira's—are understood in Ebola.