New Drug Helps Fight the Flu
Study Shows Peramivir Shortens the Length of Illness
Oct.29, 2008 (Washington, D.C.) -- The experimental drug peramivir cut short
by about one-third the number of days people were sick with the flu, Japanese
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
Kohno says that similar questionnaires were used in studies of Tamiflu and
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
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,
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.