jnd, a strategy that has worked well for me over the years is something I call "double, cut & run". When the stock reaches a price a little more than double what you paid....cut your position in half...and run that money into something else. Then hold the remainder of your NBIX shares risk-free. You'll have gotten your money back and anything else down the road is gravy.
However, that being said.....I paid $2.48/share for my NBIX and haven't sold anything yet. FDA approval jumps this over $10 instantly, and big partners like Abbott (& $140mil in the the NBIX reserves) reassure me that we're headed there.