While the new drug was not directly compared with the currently available flu drugs Tamiflu and Relenza, it appears to work at least as well, says Shigeru Kohno, MD, of the Nagasaki University Graduate School of Medicine.
"We strongly believe that peramivir will be a fine future option for influenza treatment," Kohno tells WebMD.
The findings were presented at a joint meeting of the American Society of Microbiology and the Infectious Diseases Society of America.
Peramivir vs. Placebo
The new study involved 296 people aged 20 to 64 who had the flu. They were given either a single intravenous (IV) injection of one of two doses of peramivir or a placebo injection.
Participants answered questionnaires that asked about the presence and severity of sore throat, aches and pains, cough, fatigue, and other flu symptoms.
Kohno says that similar questionnaires were used in studies of Tamiflu and Relenza.
Results showed that both doses shortened the time people were sick by 32% to 33%. The median time to alleviation of symptoms was 59 hours for those receiving the lower dose, 60 hours for those receiving the higher dose, and 82 hours for those receiving placebo.
"Patients given either dose recovered about 20 hours faster than those receiving placebo," Kohno says.
He adds that the success rates were higher than those previously reported with Tamiflu, "although we interpret this finding with caution as it involved comparison across studies." The cautionary note was given since the drugs were not directly compared in the study.
Peramivir was well tolerated and caused no serious side effects, Kohno says.
Other Flu Drugs Also in Pipeline
Tamiflu, Relenza, and peramivir are all antiviral drugs that inhibit neuraminidase, an enzyme that is critical to the spread of flu.
William Sheridan, MD, chief medical officer of BioCryst, which is helping to develop the drug, says that if approved, the drug will give flu patients another option. Relenza is given by an inhaler; Tamiflu is a pill. In contrast, the new drug is given by injection.
Other new neuraminidase inhibitors are also being developed, adds William Schaffner, MD, of Vanderbilt University School of Medicine in Nashville, Tenn.
More options are always welcome, he says. Sheridan notes that flu mutates quickly and in laboratory tests, peramivir has shown activity against viral strains that have developed resistance to currently available treatments.
The next step will be a larger, longer study known as a phase III trial. Its results, if positive, will be submitted to the FDA to gain U.S. approval for the drug, Kohno says.
The study was sponsored by BioCryst's partner for peramivir, Shionogi & Co., Ltd., of Japan.
source:webmd
