Just in time for the 2010 holidays, Americans might have several new weight-loss drugs to help them shed their extra pounds.

By the end of October, the Food and Drug Administration should reach final approval on Qnexa, developed by Vivus Inc., and Arena Pharmaceuticals’ lorcaserin. The FDA has approved an application for a third drug, Contrave, created by Orexigen Therapeutics, but a decision date hasn’t been set, according to a report in Newsmax magazine.

Qnexa has piqued the interest of health experts in its phase II trials as it not only helped patients lose weight, but also reduced their blood pressure and sleep apnea symptoms.

“These positive Qnexa data, from what is considered a sizable study for OSA [obstructive sleep apnea], are exciting for those of us in the medical community treating obese patients with hypopnea syndrome,” Dr. David Winslow said in a statement.

Qnexa includes phentermine, part of the fen-phen diet drug combination of the late 1990s that was withdrawn from the market when it was tied to heart valve damage. In the new drug, Vivus has combined phentermine to immediately reduce appetite with topiramate, an epilepsy drug, which gives a feeling of fullness over time.

“What’s important to me, for my patients, is that a drug is efficacious and safe, and that is what I’ve seen in my two years of experience with this drug,” Dr. Michelle Look, a family practitioner in San Diego told CNBC.

Look is also a lead investigator in the Qnexa clinical trial and a paid consultant for Vivus. She said patients lost an average of 10 percent of their body weight, which is “definitely much higher than we’ve seen with any other compound that had been previously approved.”

Locaserin is similar to fenfluramine (the “fen” in fen-phen), and affects appetite signals to the brain and metabolism, but does not bind to cell receptors in the heart like fenfluramine did.
Arena said study subjects lost an average of 8 percent of their weight, with only headaches as a side effect. Side effects with Qnexa include dry mouth, change in taste, and digestive issues — all of which were mild to moderate, according to Vivus.

A 10 percent weight loss will reduce the risk of Type 2 diabetes, heart disease, some cancers, and arthritis, according to the National Institutes of Health.

According to FDA guidelines, obesity drugs should reduce body weight by 5 percent after one year to be considered effective.