Source is today's Wall Street Journal page D7:

AstraZeneca will stop selling Nolvadex by the end of June in the U.S.
However generic companies such as a unit of Barr Laboratories and Teva
Pharmaceutical will be selling it as generic tamoxifen.

Poor AstraZeneca reported only  $114 million in world-wide sales for
Nolvadex in 2005, down from $134 million in 2004.  What I do not understand
is why AZ would stop selling Nolvadex as long as they are making a profit?
Obviously if Barr and Teva can make money selling tamoxifen then AZ should
be able to.

In fact I never understood why the original company would refuse to lower
prices to compete with a generic company.  Most people would take the
original brand name drug if the price and their co-pay were the same as a
generic.  Wouldn't this insure that the original company would have a sales
advantage over any company that wanted to produce a generic brand?

I know as soon as a patent runs out that drug companies try to release a
"great, new, improved version" of the patent expired drugs. However due to
cost containment and experience with the old drug, not every physician will
be persuaded to switch to the expense new drug.  So why quit making a proven
drug that is making money ?  Why let the generic companies get your
business?

Is over a hundred million dollars a year in sales such a trivial amount of
cash that it is not worth bothering with?