Yes it's common practice to sell shares in order to pay tax liabilities resulting from vested options, however if big things were truly in the works, i would have to believe any rational person would do all they can to hang on to their shares until that big event happens, including scraping together $20k in order to pay the tax from those options (which i have to believe is an easy thing to do for these high level execs).
Selling shares to pay taxes from options is IMO their way to justify selling their shares, without causing a panic.
" key management and BoD members sold stock to limit tax paying (see SEC filings)"
This is totally absurd. If big things were afoot, why would any insider sell??
First, that would be considered trading on undisclosed material info, i.e. illegal.
Second, who in the world would sell at $2 if there is something big in the works that could mean they sell at $4 (fake numbers for illustrative purposes obviously). If I told you that you can sell today for a gain of $100, and pay $30 in tax (pocketing $70), or sell tomorrow and make $1M, and pay $400k in tax (pocketing $600k), you would opt for taking your $70? Tax planning drives certain decisions, this is not one of them.
These guys have a couple of heavy albatrosses that are strangling their future:
i) cost of CVOT
ii) going up to litigate against TEVA who wants to come out with generics
Both of these things cost $$$$$. And the outcome of fighting TEVA is truly a cointoss nobody knows who will be successful (and anyone that tells you VVUS patent portfolio is rock solid and will overcome doesn't know anything about patent litigation, where anything can happen).