Oct 8 (Reuters) - Chimerix Inc said its experimental oral antiviral, which was used earlier this week to treat the first Ebola patient diagnosed in the United States, improved the survival rate of patients with a certain type of respiratory infection.
Chimerix, whose shares were up 6 percent at $35.25 premarket, said preliminary data on the drug, brincidofovir, was based on a late-stage study of 48 patients with adenovirus, a common virus that causes respiratory illnesses.
Up to Tuesday's close, the stock had risen nearly 11 percent since the company said on Monday that the drug could potentially be used to treat Ebola patients.
Chimerix said the 48 patients who took the drug had a mortality rate of 35 percent, compared with historic rates of up to 80 percent in the first month after diagnosis.
A majority of the patients also had suppression or clearance of adenovirus from the blood, the company said.
Texas Health Presbyterian Hospital said on Monday that Liberian man Thomas Eric Duncan, the first person to be diagnosed with Ebola in the United States, was receiving Chimerix's drug to treat the disease.
The drug has never been tested on laboratory animals infected with Ebola let alone in human Ebola patients.
Medical experts said the choice of the Chimerix drug may have been influenced both by the deterioration in Duncan's condition and the therapy's safety profile.
Duncan, who is fighting for his life, is on a ventilator and a kidney dialysis machine to help stabilize his condition, the hospital said on Tuesday. (Reporting by Ankur Banerjee and Rosmi Shaji; Editing by Savio D'Souza and Ted Kerr)