Chimerix Antiviral to Start in Ebola Clinical Trial

Xconomy Raleigh-Durham — 

Chimerix (NASDAQ: CMRX) is cleared to start a clinical trial studying its antiviral drug brincidofovir in patients infected with Ebola.

The Durham, NC, company announced today that the Food and Drug Administration gave the green light to test the compound in a Phase 2 trial. Chimerix gave no details on the size of the trial, nor did it give locations for where the studies would be conducted. In a presentation to investors Wednesday, Chimerix said that Phase 2 studies would be conducted in the United States and Europe, while studies of the drug for Ebola in West Africa are “under discussion.” But the company says brincidofovir tablets are available for immediate use in the studies.

Chimerix also says it plans to partner with global authorities to provide emergency access to the drug, apart from the clinical trials. Those requests must be made by doctors. The Chimerix drug has already been provided for emergency access in at least two cases. Health professionals identified those individuals as Thomas Eric Duncan, the Liberian man who died last week at Texas Health Presbyterian Hospital in Dallas, TX, and freelance journalist Ashoka Mukpo, who is being treated at Nebraska Medical Center in Omaha, NE.

Brincidofovir is still experimental and is not yet approved by the FDA to treat any viral infections. The drug is based on Gilead Science’s (NASDAQ: GILD) injectable antiviral cidofovir (Vistide). Like the Gilead drug, brincidofovir works by interfering with the process by which viruses make copies of themselves. But cidofovir has also been linked to higher risks of kidney damage. What Chimerix has done with brincidofovir is attach cidofovir to lipids. That makes the drug absorbable in the gut, which in turn makes development of the compound in a tablet form possible. The lipids also mitigate the risk of toxic effects on the kidneys from the drug.

Cidofovir was approved to treat cytomegalovirus, an infection that can set in in patients with weakened immune systems. Chimerix had also identified cytomegalovirus as a target for its brincidofovir, and so already has safety and efficacy data on brincidofovir in patients, having taken the drug into Phase 3 studies in cytomegalovirus in stem-cell-transplant patients.

Even though Chimerix made cytomegalovirus its lead drug target, the company has long touted brincidofovir as a broad spectrum antiviral. Last week, the company revealed the progress of its work developing the drug for other types of infections. Chimerix announced preliminary results showing the drug worked in an open-label study against adenovirus, a type of respiratory infection that can be fatal when it progresses in patients with weakened immune systems. Chimerix last week also revealed it started testing brincidofovir in Ebola, in laboratory tests as well as in animals, adding that it was working with the FDA on a pathway for an Ebola clinical trial.