BOSTON (

TheStreet

) --Obesity drugs are dead.

Orexigen Therapeutics

(OREX)

is done.

Arena Pharmaceuticals

(ARNA) - Get Report

is a corpse.

Vivus

(VVUS) - Get Report

is in an irreversible coma, waiting for someone to pull the plug.

The only silver lining from Tuesday's

outright and devastating rejection of Orexigen's obesity drug Contrave

is that investors need not waste time or money any longer speculating on which of these three companies will be the first to get their drug approved. The U.S. Food and Drug Administration has made it crystal clear that it has serious problems with the entire obesity drug field and that none of these drugs -- Contrave, lorcaserin or Qnexa -- have weight-loss benefits that justify the safety risks.

Orexigen shares are tanking, down 72% to $2.53 in early Tuesday trading. Vivus shares are down about 11%, while Arena's stock is also indicated lower.

So many investors and commentators, including myself, thought this three-way obesity drug race between Orexigen, Vivus and Arena would one day have a winner, even with the latter two receiving drug rejections last year. We were all wrong. The reality is that the finish line is a cliff over which all three horses just plunged to their death.

Sell-side analysts on Orexigen Therapeutics' conference call Tuesday tried to tease out something positive from the Contrave rejection -- asking management if they plan to appeal or inquiring about possible future study designs. You could almost see the little gears in their sell-side analyst brains whirling with the idea that Orexigen will need to raise money soon, so best to be as conciliatory and upbeat as possible in the hopes of snatching some of the Orexigen investment banking business.

Orexigen will need to raise money if the company pushes ahead with Contrave, but that would be a foolish decision. On the call, Orexigen CEO Michael Narachi said his first step will be to have a meeting with FDA to get more details about what the agency wants from a pre-approval cardiovascular risk outcomes study. After that, he added, the board will sit down and decide whether it's prudent to proceed or just drop Contrave altogether.

FDA is clearly concerned about data from Contrave studies showing the drug causes in an increase in blood pressure and heart rate. Any study to assess the heart safety risk of Contrave in obese patients is going to take at least four or five years and will need to enroll thousands of patients. This is a huge and expensive undertaking and at the end, the study may well find that there is a safety risk tied to Contrave.

That's what happened to

Abbott Labs

(ABT) - Get Report

and its diet drug Meridia, which was withdrawn from the market last year under pressure from FDA following the negative results from a lengthy cardiovascular outcomes study.

Orexigen must bear the responsibilities of any pre-approval study of Contrave under its partnership agreement with the Japanese drug firm

Takeda

.

If Orexigen drops Contrave, which seems like the smart and fiscally responsible move, the company could pivot to focus on the development of its second weight-loss drug Empatic. Yet the glaring problem is that both Contrave and Empatic contain bupropion, the drug at the center of the FDA's heart safety concerns.

Orexigen believes Empatic helps patients lose more weight than Contrave and has a different safety profile, but still, at this point it's hard to see how FDA would let Empatic slide without requiring a similar pre-approval heart risk study.

Meantime, Vivus and Arena each have their own significant challenges. Vivus must assuage FDA that Qnexa won't cause birth defects in babies born to women who use the drug to lose weight. Given today's Contrave rejection, concerns about Qnexa and heart safety issues are also likely to be resurrected. Arena's lorcaserin is buried under worries about cancer and heart safety risks.

The message FDA sent to the public and investors Tuesday is clear: If you're obese, don't sit around waiting for the approval of a magic pill that is going to help you lose weight.

Put down the muffin and get on the treadmill.

--Written by Adam Feuerstein in Boston.

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Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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