More than a decade ago, the fen-phen weight-loss cocktail and a related diet pill called Redux made headlines after links to heart and lung troubles forced a recall, which eventually cost Wyeth $21 billion in charges. Other prescription drugs - Abbott's Meridia and Roche's Xenical - never fared well due to side effects. Sanofi-Aventis never soldAcomplia due to psychiatric side effects. And even the over-the-counter Alli pill, which is really a version of Xenical, is suspect these days thanks to concerns over liver injury ( see here).
Now, though, a trio of would-be diet pill makers is focusing attention anew on the long-disgraced obesity market. This is underscored by Eisai's willingness to pay $50 million for the rights to sell Arena Pharmaceuticals' lorcaserin in the US; another $160 million based on development and approval milestones, and a $1.16 billion, one-time payment that may follow based on annual sales. This is a big deal, because Arena is now the first of the threesome to strike this sort of pact with a much bigger partner. In a trial, 47 percent of lorcaserin patients lost at least 5 percent of their body weight, compared with 23 percent on a placebo. Arena, however, may have an advantage over its rivals.
One is Orexigen Therapeutics, which is developing Contrave, a combo of the Wellbutrin antidepressant and a sustained release form of naltrexone, an opioid blocker used to treat addictions. This pill, which showed a 6 percent weight loss in trials, comes up for FDA review in December. And later this month, Vivus faces an FDA panel over its Qnexa pill, which combines phentermine (the part of fen-phen that wasn't fatal) and topiramate, which is sold by Johnson & Johnson as Topamax for treating seizures and migraines. One trial demonstrated nearly 15 percent weight loss.
Obesity, itself, remains a hot topic because of the growing number of overweight people are at risk for various health complications. But weight-loss cocktails that combine existing drugs may be a hard sell, especially if side effects are lurking. The Vivus meeting will almost certainly provide insight into how the FDA believes obesity should be treated. And then there's price. Everyone knows that insurers don't want to cover drugs that may be taken by a gazillion people who could lose a few pounds through other means. "Managed care doesn't want everybody to be on" a diet drug, says Bruce Leavitt, lead payer value consultant at Milliman, "especially not with what's happened in the past."
Nonetheless, one analyst remains bullish on the prospects for FDA approval. In an investor note, Jon LeCroy of Hapoalim Securities, writes the FDA wouldn't have scheduled advisory committee meetings for the drugs "if the FDA viewed the efficacy or safety data clearly warranting not approving the drugs, then there would be no need to host an expert panel." He also believes the panel experts may be inclined toward approval, since they are disposed to be in favor of new therapies. Maybe so, but given the track record, those advisory committees should exercise extra caution.
pic thx to alan cleaver on flickr