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Canada Halts Adderall Sales, Citing Deaths

February 10, 2005; Page B1

    Canadian regulators yesterday evening suspended sales of the once-daily formulation of the blockbuster attention-deficit disorder drug Adderall, citing a risk that it may cause sudden deaths.

    Adderall, used by 700,000 Americans, is one of the most popular drugs for people with the widely-diagnosed condition more formally known as attention deficit hyperactivity disorder. Shire Pharmaceuticals Group PLC sold $759 million of Adderall XR in the U.S. last year and about $10 million in Canada.

    The move by Canada puts immediate pressure on U.S. regulators who have faced criticism for their handling of drug-safety matters.

    A senior Food and Drug Administration official said the agency has examined the same data as the Canadian regulators, and "we do not believe it is strong enough at the moment to merit an immediate change to the labeling or marketing status here in the United States." Overall, he said, the rate of sudden deaths and cardiovascular problems among the patients taking the withdrawn drug "doesn't appear significantly different from the rate with other, similar drugs" used for the condition, or "from the background rate for people of the same age groups who are not taking these products."

    In a one-page letter to the company, the Canadian regulatory agency, Health Canada, said the "identified risk of sudden death following the recommended doses cannot be managed by label changes." The company said there have been 20 reports of sudden deaths on Adderall's extended release and a prior formulation of the medicine since 1994, when the drug first came on the market. Many of those deaths occurred in patients who had serious cardiac abnormalities; in other cases, the company lacked sufficient information to determine if the patients' hearts were normal or defective, Shire officials said.

    "The sudden deaths were extremely rare," a company spokesman said. More than 38 million prescriptions for the new and old versions of the drug have been written during that time.

    Shire Chief Executive Matthew Emmens said the company strongly disagrees with Health Canada's decision, which came as "an absolute complete surprise" last night. He said Shire received a call from a Health Canada official late in the day seeking voluntary withdrawal of the drug. He said he refused to pull the drug from the market and Health Canada responded by suspending it indefinitely.

    "We steadfastly disagree with their interpretation of this data," Mr. Emmens said.

    Mr. Emmens said the company intended to continue to sell the drug in the U.S. He said the U.S. FDA in the summer of 2004 reviewed the same data and sought stepped up warnings on the drug label, or package insert. The company added a third sentence to the existing black box -- the highest level of warning -- saying that misuse of the drug "may cause sudden death and serious cardiovascular adverse events."

    Shire also added a new section to another part of the label called the "warning" section, saying there were reports of sudden death at the usual doses of the drug in children with structural cardiac abnormalities or serious heart problems. "Adderall XR generally should not be used in children or adults with structural cardiac abnormalities," the new language said.

    In a news release last night, Health Canada said "the incidence of serious adverse reactions leading to death was higher in" the extended release and earlier formulations of Adderall, when added together, than in other drugs in the same class. Here, the Canadian agency's conclusion appears to differ from that of the FDA.

    Of the 20 deaths reported in patients taking Adderall, 12 were from strokes, two in children, Health Canada said. It advised patients to consult physicians immediately about their use of the drug and selecting alternatives

    Attention-deficit disorder is estimated to affect 3% to 5% of school-age children, with some projections of 10% or more. The condition also increasingly is treated in adults, some of whom are diagnosed when they seek doctors' advice about their children.

    The widespread use of Adderall and competing drugs long has raised questions about whether they are being overprescribed for children who may simply be jittery or energetic. Emerging safety concerns with Adderall will add new urgency to questions about pills that some argue may not be vital to children's health.

    The warnings about Adderall also will draw attention to the question of the safety of competing drugs used to treat attention-deficit disorder. Other stimulants prescribed are Novartis AG's Ritalin and its generic equivalent, methylphenidate, as well as Johnson & Johnson's Concerta. A newer drug, Eli Lilly & Co.'s Strattera, isn't a stimulant but has potentially been linked to serious liver side effects.

    Shire, based in Basingstoke in the United Kingdom, began marketing Adderall XR in Canada in February 2004. It was approved in the U.S. in October 2001 as a treatment for children with attention-deficit disorder and won U.S. approval for adult use last August. The older formulation of Adderall, a tablet that had to be taken more than once a day, was approved in the U.S. in 1994 and a generic version now is available. Canada is taking no action against that version, which was never marketed in the country.

    The Canadian decision is likely to create a headache for the FDA, which already is under a microscope because of questions from Congress about whether the agency reacts aggressively enough to drug-safety issues. The concerns emerged last year during congressional investigations of the FDA's response to worries about the potential risks of antidepressants, when regulators in the U.K. released stronger warnings about the drugs well before the FDA took a similar action.

    More recently, Merck & Co.'s withdrawal last fall of Vioxx because of evidence the widely used painkiller was linked to increased rates of heart attacks and stroke renewed the focus on FDA. The agency plans an advisory committee meeting next week to examine the potential risks of the remaining drugs in Vioxx's class.


"La gente es maravillosamente tolerante. Perdona todo excepto al genio."
Oscar Wilde.