U.S. drug sales grew at slowest rate since 1961: IMS

NEW YORK (Reuters) - Sales of prescription drugs in the United States grew by just 3.8 percent in 2007, marking the lowest growth rate since 1961, according to data compiled by IMS Health.

Total U.S. prescription drug sales reached $286.5 billion last year with slowing growth blamed on factors including patent expirations of lucrative medicines that opened the door to cheaper generic versions.

Other reasons cited by IMS in its annual U.S. Pharmaceutical Market Performance Review were fewer new product approvals, safety concerns, and the leveling of year-over-year growth from the Medicare Part D program.

The 3.8 percent growth rate compares to 8 percent growth seen in 2006.

"The moderating growth trend that began in 2001 resumed last year following the one-time impact on market growth in 2006 from the implementation of Medicare Part D," Murray Aitken, IMS's senior vice president for healthcare insight, said in a statement.

Cholesterol drugs, such as Pfizer Inc's Lipitor, once again led all therapy groups with prescription sales of $18.4 billion in 2007 despite a 15.4 percent decline in sales, primarily due to the availability of cheaper generics.

Acid reflux medicines known as proton pump inhibitors, including AstraZeneca's Nexium, ranked second with prescription sales of $14.1 billion and 2.8 percent growth.

Antipsychotics, such as Eli Lilly and Co's Zyprexa, overtook antidepressants as the third largest therapeutic class with $13.1 billion in sales and a 12.1 percent growth rate, according to IMS, which provides industry data on drug prescriptions and sales.

Brand name drugs with some $17 billion in sales lost patent protection in 2007, helping drive prescription volume growth of 10 percent for generic medicines.