Like that saying goes "No one ever went broke taking profits" always good to skim some off the top at some point in my opinion then buy back in on the pullback.
From what I'm reading about Clovis is that its mostly driven by speculation of a partnership or a buyout. Up 316% on the month from around $3.50 to $15+
If a Merger or acquisition does not happen this could tank because the drug they have isn't better than the competition, if it does it'll probably be a good price. I haven't started a position yet cause I'm waiting on a nice pullback for entry.