Gilead mulls repositioning failed Ebola drug in China virus 

Gilead Sciences is considering repositioning NUC inhibitor remdesivir as a treatment for the coronavirus now sweeping across parts of China. The antiviral last made headlines when Gilead tested it, with little success, as a treatment for Ebola virus.

As happened during the Ebola outbreak, the surge in cases of infection with a potentially fatal strain of the coronavirus in parts of China has led to a flurry of statements from biotechs with assets they claim could help keep the virus under control. Gilead became the latest drug developer to throw its hat into ring when it issued statements about its plans to Bloomberg Law and Reuters.

“Gilead is in active discussions with researchers and clinicians in the United States and China regarding the ongoing Wuhan coronavirus outbreak and the potential use of remdesivir as an investigational treatment,” the big biotech said. 

Based on previous outbreaks, few, if any, of the programs now being talked up will lead to drugs that make a difference, either therapeutically or commercially. However, Gilead is in a slightly different position than some of the other companies with an interest in the virus.

Whereas Moderna is applying its untested “rapid response capability” to the development of a new mRNA vaccine and other companies are at similarly early stages, Gilead has a drug that has already been tested in humans. That positions Gilead to respond more quickly to the outbreak, although it also leaves scope to doubt whether it has a drug capable of tackling coronavirus.

Gilead pushed remdesivir forward quickly in collaboration with the Centers for Disease Control and Prevention and the U.S. Army Medical Research Institute for Infectious Diseases in response to the West African Ebola virus epidemic that began in 2013. The R&D program culminated in a randomized controlled clinical trial that tested remdesivir and three other drugs in patients with Ebola.

The trial found two of the drugs were more effective than remdesivir, putting an end to efforts to establish the NUC inhibitor as a treatment option in Ebola. Despite the setback, remdesivir could emerge as a potential treatment for coronavirus.

Interest in the use of remdesivir against coronavirus is underpinned by data including the findings of early-stage tests published in 2018. The tests generated preliminary evidence that remdesivir inhibits murine hepatitis virus and Middle East respiratory syndrome coronavirus without spurring the rise of dangerous drug-resistant strains. 

“These studies define the target of GS-5734 activity and demonstrate that resistance is difficult to select, only partial and impairs fitness and virulence of MHV and SARS-CoV, supporting further development of GS-5734 as a potential effective pan-[coronavirus] antiviral,” the authors of the 2018 paper (PDF) wrote.