For a second consecutive day the broad-based S&P 500 (^GSPC -0.12%) was absolutely shellacked on rising concerns that growth in the U.S., as well as in China and other emerging markets, could slow down and stop this rally in its tracks.

Nearly all markets around the world took it on the chin as U.S. corporate earnings continue to demonstrate little top-line growth; the early portion of earnings season has delivered far more earnings outlook reductions than we're used to seeing. Coupled with the fact that China's economy is struggling to keep quarter-over-quarter growth moving in the right direction and you have all the more cause for fear to be injected into the markets.

Despite a lack of economic data today, the S&P again honed in on yesterday's weak Chinese manufacturing data and dropped by a whopping 38.17 points (-2.09%) to end the trading day at 1,790.29, its lowest close since Dec. 17.

In the face of this overwhelming negativity, small-cap biopharmaceutical company BioDelivery Sciences (BDSI) led the charge higher with a gain of 50.6% after it and partner Endo Health Solutions (ENDP 137.50%) announced positive top-line results from a first phase 3 trial involving BEMA buprenorphine as a treatment for moderate-to-severe chronic pain. The results demonstrated that the drug met its primary end point, which was a mean change in the daily average pain numerical rating scale score from baseline. These results will trigger a $10 million milestone payment from Endo to BioDelivery, but there's still a lot of work to be done and data to comb over with another phase 3 trial ongoing.

Shares of volatile Ariad Pharmaceuticals (NASDAQ: ARIA) shot higher by 19.6% after The Mail newspaper in London reported that the biopharm could be an acquisition target by three separate pharmaceutical companies.The article cited Eli Lilly as the most likely bidder, asserting that Lilly would consider paying as much as $20 per share -- nearly three times yesterday's closing price -- to acquire Ariad. As I wrote earlier today, Eli Lilly desperately needs a spark in its pipeline, as patent expirations and late-stage failures mount. However, Ariad might not be the best choice despite its tax perks, given Iclusig's recently tarnished safety profile. To me, this has all the makings of a stock to pass on.

Finally, network infrastructure products provider Juniper Networks (JNPR 0.09%) edged higher by 6.6% after reporting robust fourth-quarter results and following word that activist hedge fund Jana Partners had acquired a large stake in the company. For the quarter, Juniper reported a 7% increase in revenue to $1.27 billion; adjusted income rose to $0.43 per share, up from $0.28 in the year-ago period and $0.06 higher than Wall Street's consensus. Following its report, William Blair and Barclays boosted their ratings on Juniper to outperform and overweight, respectively. What's really stirring the pot, however, is Jana Partners' sizable stake in Juniper, with the activist hedge fund calling for steeper cost cuts from the infrastructure giant. Hedge funds have an uncanny way of unlocking shareholder value when they feel management isn't doing enough, so consider this a win-win on both accounts for Juniper's shareholders today.