Cardiome Pharma Corp., the Vancouver-based developer of heart drugs, fell the most in seven years in Nasdaq trading after U.S. regulators declined to approve its treatment for rapid, irregular heartbeat.
The Vancouver-based company closed at $9.78 (U.S.), down $2.17 or 18 per cent yesterday in Nasdaq Stock Market trading. The shares earlier fell 35 per cent. Cardiome last declined more in a day on April 6, 2001, when it lost 36 per cent. About nine million shares changed hands.
On the Toronto Stock Exchange where 838,302 shares traded yesterday, the stock fell $2.28 (Canadian) to close at $10.57.
The U.S. Food and Drug Administration asked for additional safety information about the medicine, named Kynapid, in a so-called approvable letter dated Aug. 8, Cardiome and Japanese partner Astellas Pharma Inc. said yesterday in a statement. The intravenous drug targets short-term atrial fibrillation and is Cardiome's lead product candidate.
"While this action letter could result in the need for an additional clinical study, Cardiome is optimistic that the questions raised can be satisfactorily addressed from currently available data," Bob Rieder, Cardiome's chief executive officer, said in a statement.
Atrial fibrillation affects an estimated 2.2 million people in the United States and causes the heart's upper chambers to quiver instead of pumping effectively, according to the American Heart Association. Blood may pool or clot, increasing the risk of stroke. Patients with chronic atrial fibrillation sometimes have a pacemaker implanted under the skin to regulate heart rhythm.
Kynapid was designed to be a more comfortable, faster-acting alternative to the standard treatment of electrically shocking the heart into normal rhythm. The drug worked in about half of patients studied, with an average treatment time of 10 minutes.
Side effects included two cases of extremely abnormal heart rhythm and one death in a patient who had other cardiac risk factors. Patients with acute heart attack and advanced heart failure, two of the leading causes of atrial fibrillation, were excluded from clinical testing.
A panel of outside advisers to the FDA voted 6-2 in December in favour of allowing the drug to be sold, saying the benefits for some patients outweighed the risk of potentially deadly side effects in a few.
The FDA letter asked for additional information about these side effects "in order to assure an acceptable risk benefit profile compared to" treatment with an electronic device, according to the statement. The agency also asked for a safety update from current trials.
Kynapid would be the first new intravenous treatment for rapid, irregular heartbeat in more than a decade.
Pfizer Inc.'s Corvert infusion, approved in 1995, and Tikosyn capsule, approved in 1999, are the only FDA-approved medicines to correct atrial fibrillation, according to briefing documents provided by Astellas and Cardiome. New York-based Pfizer doesn't disclose the sales of either drug.
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