Health stocks rebounded a bit from Monday's market mess on Tuesday, but slightly underperformed the broader markets. After losing roughly 3% apiece on Monday, the Nasdaq and Amex biotechnology indices closed up 2.8% and 2.4%, respectively. Big biotech Amgen regained 6.8%, while Celgene rebounded 13%. Investors are waiting to hear from ImClone ( IMCL) and its mystery flirtation as the deadline draws near for that $70-a-share bidder to make up its mind. The unknown pharmaceutical company will have to make a firm offer or withdraw its bid by midnight Wednesday. ImClone shares closed up 44 cents, or 0.7%, at $62.40. Shares of Bristol-Myers Squibb ( BMY), which last week announced a hostile tender for ImClone's shares at $62 a share, closed up $1, or 5.0%, at $20.85. Pfizer ( PFE) gave an update on its pipeline, saying that t now has 25 programs in late stage development - up from 16 six months ago. The company said the majority of advances have been in oncology, pain, inflammation, diabetes, Alzheimer's disease and schizophrenia. It is targeting between 15 and 20 regulatory submissions between 2010 and 2012. The Wall Street Journal reported late Monday that Pfizer would not develop newer products for heart disease, obesity and bone health. Shares were up 79 cents, or 4.5%, at $18.44. The publication also said that GlaxoSmithKline ( GSK) may cut up to 850 more research and development jobs - about 6% of its total R&D staff. Shares of the pharmaceutical company were up $1.38, or 3.2%, at $43.46. Brean Murray, Carret & Co analyst Jonathan Aschoff started coverage on Auxilium Pharmaceuticals ( AUXL) with a sell rating and an $18 price target. Shares were down 60 cents, or 1.8%, at $32.40. Also, Roth Capital initiated coverage on medical device company Synovis Life Technologies ( SYNO) with a hold rating and a $21 price target. Shares were off by 20 cents, or 1.1%, at $18.82.