Companies searching for anti-obesity solution in a pill

For those struggling with obesity, the dream of finding a pill that can magically make them thin seems tantalizing within reach.

However, though the pharmaceutical giants of Europe and the United States are engaged in fierce competition to develop such a drug, realization is not so easy.

Two primary types of anti-obesity drugs have been developed to date. One works to suppress the taker's appetite so they will eat less, while the other functions to prevent the absorption of fat from the user's dietary intake and excrete it as stool.

Mazindol, developed by a Swiss company, is of the first type. It is available by prescription in Japan for individuals with a body mass index (BMI) of 35 or greater for whom regular dietary and exercise remedies have proven ineffective. Orlistat, sold by a British and a Swiss firm, is an example of the second fat type, which works to excrete dietary fat.

Though these types of medicines are being used to treat obesity, there are many others that have disappeared from the market. Achieving a good balance between the drug's effectiveness and harmful side effects is difficult. One example of a drug no longer available is Dexfenfluramine. Previously approved by the Food and Drug Administration (FDA) in the United States, side effects such as valvular heart disease and suicidal tendencies were observed in users, and the maker was forced to halt development and sales. Testing of anti-obesity drugs by the FDA is becoming more stringent, and there also some doctors voicing concerns, saying, "Medicine designed to induce weight loss runs counter to the natural desire to (eat to) live."

Still, this year, three types of the first category of drugs are awaiting FDA approval and expectations for them are high. In clinical studies, Qnexa, developed by a start-up in the United States, was shown to be effective in inducing an average 10 percent loss in weight over one year and is considered to the closest to gaining approval and making it to the market. Lorcaserin, developed by a different U.S. start-up, has proved effective in reducing weight by 5.8 percent over a one-year period.

The Japanese pharmaceutical company Eisai acquired the rights to sell the drug in the United States. The global market for weight-loss drugs is expected to reach $1.8 billion (142.23 billion yen) by 2018.