[(2S)-1-(4-amino-2-oxopyrimidin-1-yl)-3-hydroxypropan-2-yl]oxymethyl-(3-hexadecoxypropoxy)phosphinic acid

Brincidofovir (CMX001) is an experimental antiviral drug being developed by Chimerix of Durham, NC, for the treatment of cytomegalovirus, adenovirus, smallpox, and ebolavirus infections. Brincidofovir is a prodrug of cidofovir. Conjugated to a lipid, the compound is designed to release cidofovir intracellularly, allowing for higher intracellular and lower plasma concentrations of cidofovir, effectively increasing its activity against dsDNA viruses, as well as oral bioavailability.
In animal trials the drug has shown activity against cytomegalovirus, adenoviruses, BK virus, smallpox, and herpes simplex viruses. Preliminary in vitro tests have also shown it to have potential for the treatment of Ebola virus disease, which is somewhat paradoxical, as Ebola is not a DNA virus.
Brincidofovir is currently in Phase III clinical trials for use in humans against cytomegalovirus and adenovirus, after testing for safety in over 1000 human subjects, and has received FDA Fast Track Designation for treatment of cytomegalovirus, adenovirus, and smallpox. Chimerix announced in December 2015 that the Phase III trials for use of the drug in preventing cytomegalovirus infection in stem cell transplant patients had failed, and in February 2016 shut down two other late-stage trials for use of the drug in preventing infection after kidney transplants. The company is planning on returning trials of the drug for use in stem cell transplant patients to Phase II, while continuing to advance a late-stage trial for use against adenovirus infections in patients suffering from weakened immune systems.
On October 6, 2014, Chimerix received an FDA authorization for emergency investigational new drug applications of brincidofovir for the treatment of Ebola virus disease. Brincidofovir was administered to the first patient diagnosed in the Ebola virus disease outbreak in the US in 2014. The patient was given the drug starting six days after hospital admission when he was already critically ill; he died four days later. Brincidofovir was also given to Ebola patient Ashoka Mukpo at the Nebraska Medical Center, who had developed the disease and then was pronounced Ebola-free and released from the Center on 22 October 2014.
In October 2014, Chimerix reported it had been given approval by the FDA to start Phase 2 trials in patients infected with ebolaviruses for brincidofovir's safety, tolerability, and efficacy. A trial commenced during January 2015 in Liberia, but was subsequently discontinued. Because of a lack of suitable subjects in Liberia, Oxford University and Médecins Sans Frontières planned to extend the trial to Sierra Leone, where there were still Ebola cases; but on the 30th of January 2015, the manufacturer decided to withdraw support for the trial and end discussion of future trials.