Levitt ( LEV) was flying high on word BFC Financial ( BFF), an investment firm that already owns about 17% of the Florida homebuilder, will buy its remaining shares in a stock-swap merger, which, based on BFC's $6.35 closing price Tuesday, is worth about $286 million, or $14.41 a share. Levitt stockholders will receive 2.27 shares of BFC for each Levitt share. Levitt was soaring $3.90, or 36%, to $14.78. BFC was slipping 4 cents to $6.31.

Palatin Technologies ( PTN) surged after pharmaceutical giant AstraZeneca ( AZN) agreed to pay the New Jersey-based company up to $310 million to develop drugs targeting melanocortin receptors. The melanocortin system, which is Palatin's main focus, has been shown to regulate homeostasis and can be used in treating obesity. Britain-based AstraZeneca will pay Palatin $10 million upfront and the rest of the total will consist of milestone payments. Palatin shares were gaining 37 cents, or 18.1%, to $2.42. AstraZeneca was recently up 20 cents to $55.75.

RedEnvelope ( REDE) widened its fiscal third-quarter profits to $5.3 million, or 56 cents a share, compared with last year's $4.1 million, or 43 cents a share. The analyst who follows the upscale-accessories retailer was looking for 49 cents a share, according to Thomson Financial. Revenue, at $57 million, was up 7.5% from a year ago but short of the $59.9 million estimate. Shares of the San Francisco-based company were rising $1.02, or 13.7%, to $8.46.

Catalyst Pharma ( CPRX) was climbing after a Stifel Nicolaus analyst stamped a buy rating on the stock, citing its CPP-109 drug candidate, which mitigates the euphoric effects of cocaine and methamphetamines to curb addiction. The analyst believes that CPP-109 could be a unique product because, to date, there haven't been any drug-addiction pharmaceuticals approved by the Food and Drug Administration. The Coral Gables, Fla., company was adding 95 cents, or 18.7%, to $6.18.

Polydex Pharma ( POLXF) lost more than half its value after its Ushershell cellulose-sulfate compound -- which was undergoing advanced-phase testing in South Africa, Benin, Uganda and India for HIV prevention in women -- was shown it may actually have the reverse effect of amplifying HIV-contraction risk. Canada-based Polydex halted the testing entirely when preliminary results at some of the trial sites indicated this possibility. Family Health International, a nonprofit organization testing cellulose sulfate in Nigeria, ceased its trial as well, given Polydex's findings. Shares were down $3.66, or 55%, to $3.

Another Canada-based drugmaker, YM Biosciences ( YMI), plummeted after it halted an advanced-phase trial -- but not due to any safety concerns. Instead its tesmilifene product, which was proposed to treat breast cancer that is metastatic (spreads to other parts of the body) or recurrent, is "very unlikely" to make a significant difference in overall survival rates compared with other treatments, as the independent Data Safety Monitoring Board advised the company. An AG Edwards analyst cut the stock's rating to hold from buy. Shares were plunging $2.07, or 54.9%, to $1.70.

Websense's ( WBSN) fourth-quarter profits dropped to $7.8 million, or 17 cents a share, compared with year-ago income of $11.1 million, or 23 cents a share, while remaining roughly in line with estimates. But the next quarter should see earnings between 19 cents and 21 cents a share, under the 25 cents a share Wall Street is seeking. The San Diego-based security-software company was losing $3.05, or 12.5%, to $21.30.

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