Durham's Chimerix gets approval to test drug on Ebola patients

Durham drug developer Chimerix said it has received fast-track federal approval to start testing an experimental antiviral drug on people infected with the Ebola virus disease.

The experimental drug will be tested on Ebola patients to measure its effectiveness against the tropical virus whose death rate has risen to 70 percent in the epidemic now raging in Africa.

The drug, called brincidofovir, is emerging as a leading candidate to combat Ebola outbreaks, and Thursday’s announcement that it will be deployed in the fight against Ebola pushed Chimerix’s stock to an all-time high.

“Brincidofovir could represent a promising solution to the epidemic that is escalating in severity,” analyst Y. Katherine Xu of the William Blair & Co. firm wrote Thursday in a research note.

“Different from most other experimental treatments, brincidofovir has an extensive human safety database and large scale manufacturing in place,” Xu wrote.

The Chimerix drug was previously available to individual Ebola patients whose doctors submitted emergency requests to the U.S. Food and Drug Administration. To date, the drug has been released under the emergency protocol to only two known patients, including Thomas Eric Duncan, the Liberian national who died of Ebola last week.

Joseph Schepers, investor relations director for Chimerix, said FDA approval would allow the drug to be tested on Ebola patients outside the United States, but he didn’t specify where. In a recent interview with FierceBiotech, an industry publication, Chimerix CEO M. Michelle Berrey said study centers were being arranged in Europe and the United States to test the drug on Ebola-infected people returning from Africa.

All the patients testing the drug will receive the medication and none would take placebos, Schepers said.

Currently three people in the United States are known to be infected with the Ebola virus. Thousands are infected in three western African countries, where more than 4,400 have died this year in the largest Ebola epidemic to erupt since the virus was discovered in 1976.

The potent Chimerix drug is an attractive alternative to other antivirals because it does not have toxic side-effects. Brincidofovir comes in tablet form and can be stored at room temperature without refrigeration.

“Brincidofovir is stable even in accelerated conditions such as high heat or high humidity, making it particularly well suited for use in tropical climates,” analyst Jonathan Aschoff, of Brean Capital, wrote in a research note Thursday.

Aschoff also noted that brincidofovir could potentially be administered as a safeguard to health care workers with high risk of Ebola exposure. Already, 236 such workers have died treating patients, according to the World Health Organization.

The company is well-stocked with the drug, having about 23,000 treatment courses “warehoused and ready to ship to combat an epidemic,” analyst Daniel Brims of Cantor Fitzgerald wrote in his research note Thursday. That quantity corresponds to enough medicine to treat 23,000 infected people.

Brincidofovir has an established safety record, based on more than 1,000 people who have taken the drug between 2009 and 2012, largely in compassionate use programs.

The drug works by inhibiting replication of certain DNA viruses; it has shown effectiveness against Ebola in laboratory cell cultures.

Brincidifovir is also being tested on common viruses that are not dangerous to healthy people but can be deadly for patients with compromised immune systems.

Company officials say the main focus for Chimerix remains developing its antiviral against a trio of viruses: smallpox; adenovirus, which causes the common cold; and cytomegalovirus, which is related to chicken pox and infects its human hosts for life but stays dormant and asymptomatic in healthy people.

Still, investors have focused on brincidofivor’s Ebola potential, pushing the company’s shares up $3.22 on Thursday to close at $35.40. The stock is up 134 percent this year.

“Once efficacy is demonstrated in either infected animals or humans, brincidofovir could be used in Ebola patients broadly and Chimerix could receive stockpiling orders from various governments,” Xu wrote.

Additionally, bricindofovir is backed by the federal government’s Biomedical Advanced Research and Development Authority. BARDA is funding $22.3 million in research to develop the Chimerix drug as a weapon against the threat of smallpox dispersed through a bioterror attack or accidental release.

The experimental drug is not expected to be approved for general public use until 2016 at the earliest.

In contrast to most other viruses, Ebola easily overwhelms a healthy immune system and typically kills half its victims.

Duncan, the Liberian who was treated for Ebola disease at Texas Health Presbyterian Hospital in Dallas, died Oct. 8. He was in advanced stages of the virus attack when he began using the Chimerix drug.

NBC News freelance cameraman Ashoka Mukpo, who is being treated for Ebola at the Nebraska Medical Center, is also receiving brincidofovir.

Since Duncan’s death, two nurses who treated him have also tested positive for the Ebola virus. It is not clear if they are taking brincidofovir, as their doctors have not publicly disclosed their course of treatment.