The European elections set off delayed market reactions as the EU begins to come unglued. The elevation again of a socialist to the French presidency and gains made by neo-Nazis in Greece show there is no political will for the austerity measures needed to return the countries to a firmer financial footing. The euro may crumble or Greece may exit the union, or both.

While the stocks below strapped on rocket packs and went even higher, resist the urge to high-five everyone in the cubicles next to you. Smart investors won't celebrate until they know why their stock surged. Without a fundamental basis for the bounce, these stocks can quickly make the return trip down.

Fit or fat?
Yesterday investors in Arena Pharmaceuticals (Nasdaq: ARNA) were as excited as a dog welcoming home its master after the FDA posted on its website its rigorous evaluation of Arena's data supporting approval of its fat-fighting drug lorcaserin. Arena's stock shot higher by 26% on the development.

Although there were many positive indicators, there's still a lot of concern as well over side effects, and even if the FDA panel approves the drug tomorrow, there's nothing to suggest that the full regulatory agency will follow suit.

Arena, VIVUS (Nasdaq: VVUS), and Orexigen Therapeutics (Nasdaq: OREX) have been rising and falling in tandem as each possible indication of approval or denial comes to the fore. Last month the three surged ahead after VIVUS got a 20-2 vote in favor of approval of Qnexa from the panel only to have their hopes dashed a few days later when the FDA said not so fast, as it wanted an additional three months to review the results.

In the past I've avoided making a CAPSCall on these biotechs because the FDA is so capricious in its decisions, but the euphoria gripping the market for these stocks -- Arena's up 83% year to date -- has me believing its investors will be in for a rude awakening. The Fool's biotech guru Brian Orelli agrees with me (or I agree with him) and suggests Arena hasn't "satisfied the FDA's safety concerns."

Add the biotech to the Fool's free portfolio tracker and tell me in the comments section below or on the Arena Pharmaceuticals CAPS page if you think as I do that the FDA's not ready to assume the risks associated with a new fat-loss drug.

A meal fit for a king
It wasn't a drug approval that sent shares of Savient Pharmaceuticals (Nasdaq: SVNT) 17% higher yesterday, but rather the defeat of a creditor trying to prevent it from restructuring its debt.

Savient's stock tumbled the other day when Tang Capital Partners, which owns some $39 million worth of debt, accused the biotech of being insolvent and asked a judge to appoint a receiver. Tang wanted the courts to prohibit any financing deal to be enjoined as well as to stop any bonuses from being paid to management. The judge, however, refused Tang's request for the restraining order, and Savient said it will now be able to raise about $44 million and extend maturity on half of its debt.

The biotech reported earnings this morning too that underscored the troubles Tang highlighted. The investment fund accused Savient of having "no reasonable prospect of continuing its business successfully" because doctors are leery of prescribing its gout treatment Krystexxa as it can lead to "extremely severe adverse reactions," including allergic anaphylaxis, which Savient noted in filings with the SEC.

Sales in the first quarter were just $3.1 million, barely higher than the $3.0 million it sold in the fourth quarter. Losses also widened to $0.49 per share, worse than the $0.46 loss analysts were expecting as costs of trying to sell Krystexxa soared.

Savient tried to sell itself one time before without success, perhaps realizing how difficult it would be to go it alone. Although other drugmakers like Abbott Labs or Merck could find Savient a natural fit since they also sell anti-inflammatory treatments, none was willing to take the bait.

Let us know on the Savient Pharmaceuticals CAPS page whether you think it will eventually get the royal treatment from a suitor, and then add it to your watchlist to see whether it can survive.

Going into orbit
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