“An epidemic of diabetes,” along with a host of new drugs for the disease, could result in a near 70% increase in spending on treatments in the USA from this year to 2009, according to a new study.

The report, published by Medco Health Solutions, one of the USA's leading pharmacy benefit managers, noted that an aging population and a rising incidence of obesity are expected to push spending growth rates on diabetes medications up 16%-20% annually as use increases each year by 8%-10% and patients will more frequently use new drug combinations to reach blood sugar targets.

The study, Medco's 2007 Drug Trend Report, an annual analysis of prescription drug spending and usage, also found that diabetes treatments were the second leading contributor in dollar terms in 2006, up 14.5%, trailing only cholesterol drugs. New treatments that act upon new targets, such as Merck & Co's Januvia (sitagliptin), a dipeptidyl peptidase-4 inhibitor, and Eli Lilly and Amylin’s incretin mimetic Byetta (exenatide), have hit the market recently and other novel drugs in the pipeline will also help push costs upward in the future.

Commenting on the findings, the benefit manager’s chief medical officer, Robert Epstein, said that the disease is “creating a significant health care concern in America," and “while prevention of type 2 diabetes needs to be a national priority, drug treatments can help prevent the onset of complications from diabetes that lead to hospitalisations, more complex treatment and dramatically higher costs."

Sharp increase in cost of cancer drugs

The Medco report also noted that “with drug regimens running $5,000 to $10,000 per month,” cancer therapies have emerged as a leading driver of drug costs with more expensive niche medications displacing older products as standard treatment. Utilisation of these cancer drugs grew 8.6% while the growth in spending reached almost 38%, overtaking rheumatologic drugs as the number one specialty drug contributor.

This sharp increase in the cost of treatment was due to the rapid adoption of expensive treatments such as Bayer’s Nexavar (sorafenib), Celgene Corp’s Revlimid (lenalidomide) and Pfizer’s Sutent (sunitinib), and Medco noted that almost 25% of all new drugs and biologics approved last year were cancer medicines and more than 500 new ones and indications for existing drugs are under development.

However despite the two growth drivers of oncology and diabetes, the report finds that 2006 drug spending in Medco's “book of business” grew by only 2.8%, largely due to the increased use of generic drugs and changes brought on by Medicare Part D in the USA. Copycat versions of blockbusters such as Merck’s cholesterol-lowerer Zocor (simvastatin) and Pfizer’s antidepressant Zoloft (sertraline) hit the market last year, “creating opportunities to better control prescription spending,” the study notes, adding that in the first quarter of 2007, the generic dispensing rate reached an all-time high of 58.2%, up 4.5% from the same period a year ago.