Chimerix drug used on US Ebola victim after swift approval

The first patient diagnosed with Ebola on US soil has been treated with an experimental therapy developed by Chimerix after a last-minute approval from the FDA.

Liberian national Thomas Duncan - who is fighting for his life in a Texas hospital - is being treated with Chimerix's brincidofovir candidate, a broad-spectrum antiviral that is already in Phase III trials to prevent cytomegalovirus (CMV) infections.

The news comes as an investigation gets underway in Spain into an Ebola case involving a female nurse who treated two infected missionaries, in what could be the first Ebola case to have been contracted outside West Africa.

The nurse was reported to have been wearing protective at all times when in contact with the two patients, who have since died, and the probe is centring on how safety measures failed. Efforts are also underway to identify and test all people with whom she may have been in contact since being exposed to the virus.

The outbreak has killed more than 3,400 people since it officially began in West Africa in March and has now started to accelerate, infecting almost 7,200 people at last count, according to the World Health Organization (WHO).

Doctors treating Duncan - who contracted the disease in Africa but was asymptomatic until he had been in the US for several days - were cleared to administer brincidofovir after the FDA approved an Emergency Investigational New Drug Application (EIND) for the drug yesterday.

"Based on in vitro data ... we are hopeful that brincidofovir may offer a potential treatment for Ebola virus disease during this outbreak," said Chimerix's chief executive Michelle Berrey.

More and more companies are accelerating Ebola projects as the death toll rises, and the WHO has already issued guidance indicating it is ethically acceptable for patients to be treated with experimental therapies and vaccines given the seriousness of the outbreak.

One unapproved drug - MAPP Biologicals' ZMapp - was used on some of the first cases among healthcare and aid workers, but supplies are now exhausted, while others under test include Biocryst's BCX 4430, Fab'entech's Hyperimmune horse sera, Sarepta's AVI-7537, Toyama/MediVector's favipiravir, and Tekmira's TKM-Ebola, as well as preclinical candidates from NanoViricides.

The European Medicines Agency (EMA) started a review of potential candidates last month to help guide treatment decisions, while the WHO has also organised clinical testing of two vaccine candidates - GlaxoSmithKline's cAd3-ZEBOV and NewLink Genetics' rVSV-ZEBOV - that could start efficacy trials in early 2015. Johnson & Johnson's Crucell unit is also developing a vaccine that could start safety trials next year.

Meanwhile, scientists at Lancaster University have predicted that there is a 75 per cent chance of the virus reaching France by the end of this month, and a 50 per cent chance it will reach the UK, given the air traffic links between the two countries and West Africa.