As the patent cliff looms large for companies, some have found novel ways to extend patents. If successful, that means higher costs for users, but an article published in the British Medical Journal (BMJ) suggests that there are darker sides to some of these techniques.
Eisai's blockbuster Alzheimer's drug Aricept, sold in the U.S. by Pfizer ($PFE), had generated more than $2 billion in annual sales since its approval in 1996, according to the article, but faced patent expiration in 2009 and potential competition from generics.
The BMJ article, picked up by The New York Times, points out that the patent was extended on a 23 mg dosage that caused more nausea and vomiting and showed little, if any, additional benefit. That is a dosage that you couldn't get by combining any of the 5 mg or 10 mg doses being sold. The added side affects, the BMJ says, could be dangerous for elderly patients with Alzheimer's. The drug did lose protection in 2010 and sales have declined, according to the Times, but the BMJ article raises questions about whether the conditions under which the patent was extended put patients at risk.
Companies have used other tactics to hold onto patents, like offering extended-release versions, but changing the dosage, particularly to such an unusual amounts, is relatively new, BMJ points out. In the case of Aricept, it suggests it also was potentially dangerous.
FDA reviewers recommended against the new dosage, but the drug was approved by the director of the FDA's neurology products division. He found the chance of improved functioning warranted the extension, although a study showed little improvement. The FDA and officials with Eisai had no comment about the BMJ's report.