AstraZeneca issues Crestor safety warning
pharmafile | May 20, 2004 | News story | |
AstraZeneca has written to healthcare professionals in the UK after a small number of patients reported serious side effects after taking high doses of its cholesterol treatment Crestor.
Just four cases of rhabdomyolosis associated with Crestor have been reported, among the 110,000 UK patients taking the drug in its first year on the market, but the serious, sometimes fatal condition is the same that led to Bayer's Lipobay/Baycol being withdrawn in 2001.
The Crestor cases were all in patients who had received higher than the recommended 10mg starting dose of the drug and who had pre-existing risk factors for rhabdomyolosis, the potentially fatal kidney damage which can result from myopathy, the muscle wasting side effect sometimes seen in patients taking statins.
AstraZeneca's letter reminds prescribers that the starting dose is 10mg, and can be increased to 20mg after four weeks if necessary, but that the higher 40mg dose was rarely needed.
Despite the relatively small risk, the warning could seriously undermine Crestor's reputation as a major rival to Pfizer's Lipitor (atorvastatin) and the most tried and tested drug in the class, simvastatin.
Crestor can claim to be the most effective of all the statins in lowering cholesterol levels, but the drug has been unable to shake off fears about its safety in high doses ever since it scrapped plans to market an 80mg dose after serious side effects were seen in clinical trials.
US consumer watchdog organisation Public Citizen has opposed the marketing of Crestor on safety grounds, since before its US approval in August 2003, claiming the FDA had been irresponsible not to demand regular urine and blood tests for signs of kidney damage.
In March 2003, its campaign highlighting rhabdomyolosis cases in patients around the world resulted in sales falling 3% in the following week, but they have now resumed their upward trend.
AstraZeneca has issued a detailed response to Public Citizen's campaign, refuting in particular the claim that a 39-year-old patient had died because of Crestor side effects, apparently caused because of an unrelated heart attack.
In the UK, Crestor achieved the best ever launch of a new product, and has also enjoyed rapid uptake in its first EU market, the Netherlands, but is still awaiting launch in Europe's biggest market Germany. The company is at loggerheads with the regulators over pricing and labelling claims, still unresolved from when the country dropped out of the mutual recognition procedure in March 2003.
