Number of COX-2 Inhibitor Prescriptions Decreased by 43% in 2004, IMS Health Study Finds
The number of COX-2 inhibitor prescriptions decreased by 43% between December 2003 and December 2004, according to a study released on Monday by the pharmaceutical information and consulting company IMS Health, the AP/Seattle Post-Intelligencer reports. According to the study, the number of COX-2 inhibitor prescriptions filled at retail and mail-order pharmacies and nursing homes decreased to 2.7 million in December 2004 from 4.5 million in September 2004, when Merck voluntarily withdrew the COX-2 inhibitor Vioxx from the market over safety concerns.
Lisa Morris, global marketing director at IMS, said that among Vioxx patients who continued to take prescription pain medications after the withdrawal, two-thirds switched to other COX-2 inhibitors, and one-third switched to older nonsteroidal anti-inflammatory drugs.
Impact Rx, which tracks physician prescriptions, found that, in the week after the Vioxx withdrawal, new prescriptions for the COX-2 inhibitors Celebrex and Bextra, both manufactured by Pfizer, increased by 25%. However, the percentage decreased to 8% by February as new reports indicated safety concerns for all COX-2 inhibitors.
FDA advisory committees on Wednesday will begin a three-day meeting to discuss potential restrictions on sales of COX-2 inhibitors. Hemant Shah, a pharmaceutical industry analyst for HKS, said that FDA could require stronger warnings on COX-2 inhibitor labels, a move that he said likely would reduce future sales of the medications (Johnson, AP/Seattle Post-Intelligencer, 2/15).
According to IMS study, U.S. sales of prescription drugs rose by 8.3% from $217.3 billion in 2003 to $235.4 billion in 2004, the smallest increase in nine years, Bloomberg/Los Angeles Times reports.
IMS said that safety concerns over COX-2 inhibitors, a mild flu season, higher consumer prescription drug copayments and safety concerns over antidepressants contributed to the results. Medicare prescription drug discount cards and the reimportation of medications from abroad had only a small effect on the results, IMS said.
IMS predicted that prescription drug sales would increase by less than 10% in 2005 as a result of new cost-control measures implemented by managed care companies and the loss of patent protection for a number of popular brand-name medications (Bloomberg/Los Angeles Times, 2/15).