Does anybody have an official press release from the makers of Opana (or, even better, the U.S. FDA) in regards to this?
I'm looking into this on the Endo website. They do have a product listing for a new formulation of Opana ER, so I checked it out. The older one had the TimeRx gelling mechanism, which was the same as in the Xanax XR.
Here is the listing for the inactive ingridients in the old vs new formulation, and we can compare that to the new OxyContin inactives.
Opana ER Inactive Ingridients (original forumlation)
The tablets contain the following inactive ingredients: hypromellose, methylparaben, silicified microcrystalline cellulose, sodium stearyl fumarate, TIMERx-N, titanium dioxide, and triacetin. The 5 mg, 10 mg, 15 mg, 20 mg, and 30 mg tablets also contain macrogol, and polysorbate 80. In addition, the 5 mg, 7.5 mg, and 30 mg tablets contain iron oxide red.
- The 7.5 mg tablets contain iron oxide black, and iron oxide yellow.
- The 10 mg tablets contain FD&C yellow No. 6.
- The 20 mg tablets contain FD&C blue No. 1, FD&C yellow No. 6, and D&C yellow No. 10.
- The 40 mg tablets contain FD&C yellow No. 6, D&C yellow No. 10, and lactose monohydrate.
Opana ER Inactive Ingridients (new forumlation)
The tablets contain the following inactive ingredients: hypromellose, polyethylene oxide,
polyethylene glycol, α-tocopherol, citric acid, polyvinyl alcohol, titanium dioxide, macrogol and talc. In addition, the 5 mg, 7.5 mg and 30 mg tablets contain iron oxide red. The 7.5 mg tablets contain iron oxide black, and iron oxide yellow.
- The 10 mg tablets contain FD&C yellow No. 6.
- The 20 mg tablets contain FD&C blue No. 1, FD&C yellow No. 6, and D&C yellow No. 10.
- The 40 mg tablets contain FD&C yellow No. 6, and D&C yellow No. 10
OxyContin/OxyNeo Inactive Ingridients
Inactive ingredients in all strengths: butylated hydroxytoluene (BHT), hypromellose,
polyethylene glycol 400, polyethylene oxide, magnesium stearate, titanium dioxide.
• The 10 mg tablets also contain: hydroxypropyl cellulose.
• The 15 mg tablets also contain: black iron oxide, yellow iron oxide, and red iron oxide.
• The 20 mg tablets also contain: polysorbate 80 and red iron oxide.
• The 30 mg tablets also contain: polysorbate 80, red iron oxide, yellow iron oxide, and black iron oxide.
• The 40 mg tablets also contain: polysorbate 80 and yellow iron oxide.
• The 60 mg tablets also contain: polysorbate 80, red iron oxide and black iron oxide.
• The 80 mg tablets also contain: hydroxypropyl cellulose, yellow iron oxide and FD&C Blue #2/Indigo Carmine Aluminum Lake.
It appears that the new formulation of Opana ER is not the same as the OP OxyContin. I underlined the only inactive ingridient that was not in the older formulation but is now in the new Opana ER forumulation, and is also found in the OxyContin formulation, and it was the polyethylene glycol (which might not be exactly the same since one has "400" after it). If that is the only thing that makes up the taper resistance in the OxyContin, then the Opana will be the same way I guess, but I doubt that the one ingridient does it all. That doesn't mean that this will be any more or less effective though.
I am not a chemist so all of this is an educated guess. Feel free to point out anything that I may have incorrect.
For those of you interested in doing your own research, here is where the product listings are found:
http://www.endo.com/endopharma/our-products
http://www.purduepharma.com/Products/Prescription/Pages/default.aspx