Top 200 Prescription Drugs of 2006

MAY 01, 2007
Ed Lamb

Large increases in prescriptions for and sales of generics and biologics were the major stories for the US pharmaceutical industry in 2006. (See the Top 200 tables on pages 36 and 37.) The primary driver of these trends appears to have been the launch of the full Medicare Part D benefit, as the program for seniors and disabled individuals greatly increased medication access to people who, in the past, had no or very limited drug coverage. Another major factor behind the continued rise of generics was the market entry of multiple unbranded competitors to blockbusters such as Merck's Zocor (simvastatin) and Pfizer's Zoloft (sertraline).

Before proceeding to a discussion of those overall trends, here is a look at the numbers for selected products and therapeutic categories:

?Total drug sales increased by 8.3% from 2005, to $274.9 billion1

?Prescriptions dispensed grew to 3.7 billion during the past year, an increase of 4.6%

?Lipitor (atorvastatin; Pfizer) once again topped the lists of most commonly prescribed and purchased medications

?Amgen's antianemia injectable Aranesp (darbepoetin alfa) led all gainers among Top 20 earners, with an increase in revenues of 42%

?Statins, proton pump inhibitors, and antidepressants were the top-earning drug categories. Antineoplastic monoclonal antibodies, the 7thranked class, trailed only statins in dollar growth.2

?New to the Top 20 list for prescriptions were Advair Diskus (fluticasone propionate and salmeterol xinafoate; GlaxoSmithKline), Mylan's furosemide, Teva's lisinopril, and Barr's warfarin sodium. The angiotensin-converting enzyme inhibitor from Teva (lisinopril) rose the most, from 43rd place in 2005 to 13th place in 2006.

?New to the Top 20 list for sales were Remicade (infliximab; Centocor) and Lexapro (escitalopram; Forest). They moved up from 21 and 23 to 18 and 19, respectively.

More Patients Getting More Generic Drugs

A telling statistic is that generic products dispensed to Medicare Part D beneficiaries made up 63% of the total prescription volume last year.1 Medicare requires coverage of nearly every drug in the classes of antidepressants, antipsychotics, anticonvulsants, antiretrovirals, antineoplastics, and immunosuppressants. As the Part D rolls grow from the current estimate of 24 million, and as more generics become available, drug plans can be expected to choose lowercost products over higher-priced ones.3

Patients and payers also can expect to see increasing numbers of generic drug approvals and approvals of competitors to brand name drugs. In 2006, the FDA approved 371 generic drug products, up from 361 in 2005.4,5

More significant than the number, though, was the type. Important products that went off or lost their patent protection in 2006 included Zoloft; Zocor; Plavix (clopidogrel; sanofi-aventis/Bristol- Myers Squibb); Pravachol (pravastatin; Bristol-Myers Squibb); and Mobic (meloxicam; Boehringer Ingelheim). The results of such an occurrence can be dramatic. To cite just 1 example, the lipid-lowering Zocor dropped from 2nd place in the number of prescriptions in 2005 to 25th place in 2006.1

Products that will have generic competition for the first time this year include Prevacid (lansoprazole; TAP) and Imitrex (sumatriptan; GlaxoSmithKline).6

Biologics Growing Rapidly

Interestingly, 6 generic products but no biotech products are in the Top 20 prescribed, but the opposite is true for the list of Top 20 drug sales. This disparity may not be surprising when a year's worth of unbranded lisinopril can cost as little as $300, but a week's worth of Aranesp therapy can cost more than $1000.7,8 The biotech segment's rapid growth in revenues, however, is attributable in part to the availability of Medicare coverage for the products.

For the next 4 years, IMS Health forecasts continued annual total pharmaceutical sales growth in the range of 6% to 9%. Generics and biologics will continue to grow more rapidly than the entire market.1

Mr. Lamb is a freelance pharmacy writer living in Virginia Beach,Va, and president of Thorough Cursor Inc.


1. IMS Health. IMS Health reports U.S. prescription sales jump 8.3 percent in 2006, to $274.9 billion. Press release. March 8, 2007.

2. IMS Health. Top 10 Therapeutic Classes by U.S. Sales. IMS Health Web site. Available at:,2777,6599_80408854_80411855,00.html. Accessed March 11, 2007.

3. Centers for Medicare & Medicaid Services. Medicare drug plans strong and growing. Press release. January 30, 2007.

4. Buehler GJ. Office of Generic Drugs update. Presented at: Annual Meeting of the Generic Pharmaceutical Association; Boca Raton, Fla; February 18, 2006.

5. US Food and Drug Administration, Office of Generic Drugs. Generic Drug Approvals. Office of Generic Drugs Web site. Available at: Accessed February 6, 2007.

6. US Food and Drug Administration. Electronic Orange Book. Available at: Accessed March 11, 2007.

7. Available at: Accessed March 11, 2007.

8. Bio Scrip. Available at: Accessed March 11, 2007.