Estimating generic availability for Razadyne ER, Aricept, Topamax

[diana.papshev]

The following is first in the series of specific requests from our members. Incidentally, these cases consistently highlight that if a first-time generic has been approved, there is no guarantee that it will reach retail shelves or that the approval will be permanent (appeals can always affect the FDA’s decision).

1. Razadyne ER

• FDA has not issued tentative approvals yet (source: Drugs@FDA)
• U.S. District Court ruled in favor of Barr Laboratories, finding the ‘318 patent invalid, as announced on 8/28/2008. In the same press release, Barr announced final FDA approval of galantamine hydrobromide (immediate and extended release) and immediate plans for launch. However, Ortho-McNeil is planning to appeal. (source: Barr press release 8/08)

2. Aricept

• Teva has received final FDA approval for the generic donepezil on 4/28/2008 (source: Drugs@FDA).
• However, U.S. District Court has granted a preliminary injunction until the trial can be held, which has not been scheduled yet. At issue is the enforceability of the ‘841 patent, which is set to expire on 11/25/2010. (sources: Teva Press release 3/08; Bloomberg.com news release 3/08; FDA’s Orange Book)

3. Topamax

• Mylan’s topiramate has received a tentative approval, followed by a final approval, which was then reverted back to a tentative approval (source: FDA Letter)
• US Court ruled against Mylan by confirming the validity of the ‘006 patent, which now has been extended to March 2009 for pediatric exclusivity (source: Johnson and Johnson press release 7/08)
• FDA approved generics for 25, 50, 100 and 200mg tablets on 3/27/09 for various manufacturers (see:FDA update on generic drugs for April 1, 2009)