Highly-anticipated obesity drugs
In June of this year, the Food and Drug Administration approved the first weight-loss drug in 13 years with its approval of Arena Pharmaceuticals Inc's Belviq.
Belviq was one of three weight-loss medications hoping for approval by the FDA after initial rejections. Then in July came the approval of Vivus Inc's Qsmyia.
With obesity rates in the country nearing 35% of the adult population, a number of physicians have called on the FDA to approve new weight loss treatments. Currently a number of companies, recognizing the profits that can come from such efforts, are researching and developing approaches to take to create effective anti-obesity drugs.
But for decades now anti-obesity drugs have caused enough health trouble that, if they're approved at all, they're quickly withdrawn from the market. Most recently Abbott Laboratories had its drug Meridia withdrawn in 2010 when it indicated increased hearty attack and stroke.
Unfortunately, the new drugs under development don't seem all that much safer. Their approval indicates the FDA is more willing to make drugs available, despite lingering safety issues.
So let's step back and take a look at the recent history of anti-obesity drugs.
Combination weight drugs, known as "rainbow pills, were a risky a stew of amphetamine (such as phendematrezine), laxatives, and thyroid hormones. These comprised the diet drugs, which suppress appetite by causing feelings of satiety (fullness).
The best known of these anti-obesity drugs was phentermine which received FDA approval in 1959. It stimulates the release of norepephrine. In 1990, Fenfluraminine, was combined with phentermine known as "Fen-Phen," which is only safe if used for a very short term--less than 12 weeks. Dangerous side effects, especially to the heart, continued to accrue. It is classified as a Schedule IV drug, with potential for abuse.
Pancreatic lipase inhibitors or gut absorption
Xenical (orlistat), employs a different weight loss mechanism, impairing fat absorption and digestion. While there has been modest weight loss on these drugs, there have also been reports of fecal incontinence, and kidney stones and rare liver injuries have also been reported.
Neurotransmitter inhibitor; Meridia (sibutramine), works effectively by blocking both norepinephrine and serotonin reuptake. Unfortunately sibutramine has been withdrawn from the market due to cardiovascular safety concerns (hypertension and myocardial infarction).
Diabetes drug Metformin (glucophage) helps decrease the amount of sugar the body absorbs from food.
Topomax (topiramiate), an anti-convulsant sold by Johnson & Johnson, also used in treating bi-polar disorder, often increases satiety
Finally, naltrexone (Depade, ReVia) help drinkers stop drinking.
New Anti-Obesity Drugs in 2012
So let's return to the recent FDA approvals of news anti-obesity treatments, the first approval of a long-term weight loss medication since 1999.
Belviq works on brain receptors for serotonin, a neurotransmitter that triggers feelings of satiety.
Less than a month later, the FDA approved Qsymia, which targets multiple brain signals that drive people to eat--a unique approach.
The one-two approval of Qsymia and Belviq indicate the FDA's new willingness to make weight loss meds available, despite safety issues.
And the need is there. Let's look at the ugly facts. As the Scientific American blog on the topic notes, according to the Centers for Disease Control and Prevention, over one-third of adults in the U.S. are obese. And, to make matters worse, while 78 million U.S. adults are obese, another 34% are overweight. Being overweight is the second leading cause of preventable death, after smoking, in the U.S. and is expected to rise to 42% by 2030.
Currently a number of companies, recognizing the profits that can come from efforts to minimize the risks of obesity, are researching and developing approaches to take to create effective anti-obesity drugs. The FDA's close approval of Qsymia and Belviq suggests the companies have support in high places.
Despite its impressive performance in research trials, Vivius's Qsymia is not a complete breakthrough in terms of medicine's approach to obesity. Qsymia's modeling itself on phentermine and topiramate makes it just a novel re-mixing of anti-obesity approaches.
Both drugs have uphill battles to climb. The FDA rejected Qsymia in 2010 over concerns that it could cause birth defects if taken by pregnant women. The company came up with a plan designed to minimizes the chance of women becoming pregnant while on the pill d the heart health fears from Fen-Phen, the company came up with a plan to prevent patients with recent or unstable heart disease from taking the pill. Not finished yet, the FDA said the company had to do studies of the heart before patients could start taking Qsymia.
That may sound like chip-chip-chipping away at Qsymia's roll-out plan and California-based Vivus Inc. plans a slow roll-out. But according to Fox News, estimates are that the new pill could earn more than $1 billion in sales through 2016.
Rival Arena Pharmaceuticals of San Diego plans to start selling Belviq in early 2013.
We sure could use safe anti-obesity drugs. Time, and thousands of patients, will tell whether we have an answer or more of the same misery.