Swiss pharmaceutical firm Roche is studying the possibility of selling its obesity drug Xenical as an over-the-counter product.
The move, which follows disappointing sales of the prescription medicine, would allow the product to compete with a range of non-prescription diet pills.
But industry analysts said regulators might block any switch given its reputation for side effects.
The company has already applied to have Xenical sold over the counter in Australia. The National Drugs and Poisons Schedule Committee, however, turned down its request last week.
Drug companies typically wait until the patent on a prescription drug expires before seeking to switch it to over the counter. But in the case of Xenical an earlier transfer could make commercial sense, given the wide appeal of an effective weight-loss therapy.
Xenical was hailed as a breakthrough in the treatment of obesity, the fastest growing medical problem in the Western world, when it was brought to market in 1998. But the product has failed to live up to its promise.