Tamiflu warning in Japan after child suicides *
· Doctors told not to give drug to teenagers
· Concern over favoured treatment for bird flu
Justin McCurry in Tokyo and Sarah Boseley
Thursday March 22, 2007
The Guardian
Concerns about the anti-flu drug Tamiflu deepened yesterday after
doctors in Japan were warned against prescribing it to teenagers because
of several cases in which young patients committed suicide or harmed
themselves.
Japan's health ministry decided to act after a boy and a girl, both 14,
fell to their deaths in suspected suicides last month and two
12-year-old boys suffered minor injuries after falling from buildings.
The move is likely to fuel anxieties about Tamiflu, which is being
stockpiled around the world as the best available drug to combat a bird
flu epidemic. The US Food and Drug Administration studied the evidence
on deaths linked to the drug last November. Despite concluding that the
drug should continue to be used, the US and Canada have asked its
manufacturer, the Swiss pharmaceutical company Roche, to warn in its
labelling that Tamiflu may cause abnormal behaviour.
The possible side effects came to light in 2005, when 12 children died
and 32 exhibited abnormal behaviour, including running on to the road
and falling from buildings.
Since it was approved in Japan in 2001, 54 people have died while taking
Tamiflu, which is imported to Japan by Chugai Pharmaceutical.
"As well as changing the warning distributed with the drug, we have
directed Chugai Pharmaceutical to raise awareness among medical
professionals of the risk of abnormal behaviour after taking Tamiflu,"
the ministry said. "While no causal relationships have been established,
we judged it was necessary to warn doctors."
But Rokuro Hama, a doctor who drew attention 18 months ago to the deaths
in Japan, said he was disappointed that the ministry's action was
limited to a warning over teenagers.
"More deaths are reported in infants and adults," he said. "There have
been 38 cases of sudden deaths, of which 23 were adults and 15 were
under 10 years old."
They died, he said, of respiratory suppression, suggesting the drug may
have a similar effect to a sedative, alcohol or an anaesthetic. When the
US authorities looked at the evidence in November, they said the
possibility that Tamiflu was the cause of the sudden deaths could not be
ruled out.
Roche insisted the drug was safe. It said there was no established
causal link between Tamiflu and neuropsychiatric symptoms. Clinical
studies in the US had shown that children being given the drug as a
treatment for flu were less likely to exhibit such symptoms as delirium,
delusion and self-harm than those not receiving treatment. A study by
Japanese health authorities had also found no increase in psychiatric
symptoms among patients taking Tamiflu.
"Influenza-associated delirium and neuropsychiatric disorders are not
uncommon and occur in the United States in approximately four of every
100,000 influenza patients, resulting in hospitalisation," Roche said.
The company said that more than 45 million sufferers worldwide had taken
Tamiflu, and the rate of psychiatric symptoms was one in 37,000
patients. Incidents that led to deaths occurred in only one in 5 million
patients.
Japan has proved a lucrative market for Tamiflu. During the 2004-05 flu
season, 6 million of an estimated 16 million Japanese sufferers took the
drug. Doctors have been told not to prescribe it for patients aged
10-20, apart from those considered at high risk of developing serious
flu-related symptoms.
People caring for young patients taking Tamiflu will be told not to
leave them unattended for at least the first two days of their treatment.
Chugai said it accepted the guidelines and would raise public awareness
of potential problems.