Cramer said Celgene is a reminder of the speculative nature of owning biotech stocks, especially those that rely on a single drug to prosper. He said he's still a believer in Celgene at these lower levels, albeit not as emphatically as before. As for Onyx, Cramer said that company may still be a takeover target, but after the stock's big run up he's not willing to chase it higher. --Written by Scott Rutt in Washington, D.C. To contact the writer of this article, click here: Scott Rutt. To follow the writer on Twitter, go to http://twitter.com/scottrutt. To submit a news tip, send an email to: firstname.lastname@example.org. To watch replays of Cramer's video segments, visit the Mad Money page on CNBC.