Pharmaceutical companies view the worldwide obesity epidemic as a tremendous opportunity for profit. After being rejected initially by the FDA over safety concerns, a drug branded as Belviq is the most recent entry into the anti-obesity drug market. If it is anything like its predecessors, Belviq may eventually be pulled from the market after its side effects are better understood.

Obesity drug billions
According to the drug research firm Decision Resources, the obesity drug market will increase more than six-fold over the next decade, swelling from $420 million in 2010 to $2.6 billion in 2020 in the U.S., France, Germany, Italy, Spain, the U.K. and Japan.
Belviq became available in U.S. pharmacies June 7. The drug is intended to suppress appetite by activating brain receptors for serotonin, a neurotransmitter that controls feelings of fullness, or satiety. Arena, the drug company pushing Belviq, claims the drug helps obese patients lose an average of about 5 percent of their body weight when taken in combination with cutting calories and increasing exercise.
Little effect but side effects
Belviq is expensive. The wholesale cost to pharmacies for a patient’s one-month supply is $200. According to Arena, the drug must be taken for the rest of one’s life to be effective. Patients could also expect a lifetime of side effects, including headache, dizziness, fatigue, nausea, dry mouth and constipation. Diabetics on Belviq could expect low blood sugar, headache, back pain, cough and fatigue. Hallucinations and memory loss occurred in rare cases.
In addition to the price of a Belviq prescription, the side effects could be too much of a price to pay for a drug that doesn’t have much effect on weight loss. In clinical trials, the average weight loss after a year on Belviq was 3.7 percent more than placebo—the equivalent of a 250-pound person losing 10 pounds—less than a pound per month. Small changes in diet and exercise habits alone could get better results.
Belviq initially rejected
In 2010, the FDA rejected Belviq for approval and demanded more evidence for its safety. There was concern the drug caused tumors in animals and heart-valve defects in people. A similar serotonin-based drug—Fenfluramine (the fen in fen-phen)—was pulled from the market in 1997 because of the same heart concerns.
Arena eventually convinced the FDA that heart problems would not occur at the dose limits of a Belviq prescription. However, the company is required to conduct six studies now that the drug has reached the market to keep track of how many people suffer heart attacks or strokes after taking it.
Previous obesity drugs unsafe
Another obesity drug released last fall—Qsymia is also designed to suppress appetite and increase the feeling of fullness. The FDA originally rejected Qsymia because it increases the risk of birth defects. Multiple sclerosis is among the side effects that have emerged, which include increased heart rate, tingling of hands and feet, insomnia, dizziness, constipation and dry mouth.
It remains to be seen whether Belviq and Qsymia follow in the failed footsteps of other obesity drugs, such as amphetamines (addiction), fen-phen (heart valve defects, lung damage, sudden death), Meridia (major cardiac events) and Orlistat (anal soilage).
Magical thinking
In an interview about Belviq and Qsymia with USA Today, Sidney Wolfe, founder and senior adviser of the health research group at Public Citizen, said, “We strongly oppose both of them. They both have serious dangers. Its magical thinking to believe that you can turn off something as complex as hunger without affecting different systems, especially the cardiovascular system.”
Source: USA Today, TIME, ABC News, Fierce Biotech