Time is running out on the U.S. patents for many of the most popular brand-name drugs. Unless original exclusivity dates are somehow extended, over the next several years generic versions of many well-known best-selling drugs will become available.

Pharmacists will need to stay abreast of these changes as consumers struggling to cope with the high cost of prescription medications turn to them with the question "Is there a generic for that?" Increasingly, over the next several years, the answer will be yes.

Off patent in 2009 and 2010

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Prevacid (lansoprazole), Takeda's blockbuster heartburn and acid reflux medication, will see its patent expire in 2009 and will be marketed in an over-the-counter version by Novartis, which has acquired the rights.²

Three big-name drugs for the treatment of migraine — Ortho-McNeill's Topamax (topiramate); Novartis' Migranal (dihydroergotamine); and GSK's Imitrex (sumatriptan) — are going off patent this year. A generic version of Topamax already has been approved by FDA.³ GSK is evaluating in trials a spinoff Imitrex-plus-naproxen combination drug, Trexima, which it hopes to launch to replace lost sales.^4,5

Generic formulations of Lamictal (lamotrigine), GSK's treatment for bipolar disorder and epilepsy, which has lost its patent protection, have been approved by FDA. GSK obtained FDA approval in June, however, to market its Lamictal XR (extended release) epilepsy drug, again in the hope of replacing sales expected to be lost to the generic.⁶

The patent for UCB's Keppra (levetiracetam), also for the treatment of epilepsy, was another to reach expiration in 2009.

Patents for many blockbuster brand-name drugs begin expiring at a rapid pace in 2010 and will continue for the next few years. Facing increased competition from generics, drug companies are busy developing new pipeline drugs and devising strategies to try to hold onto sales for their drugs facing patent expiration.

Lipitor (atorvastatin) — Pfizer's blockbuster cholesterol pill goes off patent in March 2010. Lipitor is the best-selling drug in the world, with nearly $13 billion in sales.⁷ Pfizer has struck a deal with Ranbaxy Laboratories that will enable release of the generic form outside the United States before patents run out, but delays U.S. release until November 2011.⁸

Arimidex (anastrozole) — AstraZeneca's after-surgery treatment for postmenopausal women with early breast cancer was set to expire in December 2009, but an extension was granted so that pediatric studies could be made. It now looks as if June 2010 is the earliest a generic version could become available.⁹

Aricept (donepezil) — Pfizer/Eisai is to lose patent protection in 2010 on this treatment for symptoms of early Alzheimer's. Teva has gained tentative FDA approval to market its generic version; however, Eisai and Teva are locked in a patent challenge, keeping the generic off the market for now.¹⁰