“I’m excited to have a potential new medication to add to existing treatment options for my patients who struggle with their weight despite making optimal lifestyle changes,” says Fatima Cody Stanford, MD, MPH, an instructor of medicine and pediatrics at Harvard Medical School in Boston who specializes in obesity medicine. More than 2 out of 3 American adults are overweight or obese, according to the Department of Health and Human Services. A person with a BMI from 25 to 29.9 is considered overweight, and a person with a BMI of over 30 is considered obese. “Unlike the other medications that are approved by the FDA, this is the lowest BMI that has ever been considered by the FDA for weight regulation with anti-obesity medications,” says Dr. Stanford. Typically, the FDA approves anti-obesity medication for persons who have a BMI of 30 or greater (classified as obese) or who have a BMI of 27 or higher with existing health conditions, such as type 2 diabetes, obstructive sleep apnea, and heart disease, she says. According to the National Heart, Lung, and Blood Institute (NHLBI), BMI is calculated based on a person’s weight and height, and the same formula is used for both men and women. For example, a person who is 5 feet 4 inches tall and weighs 145 or more pounds (lbs) is considered overweight. If that person weighs more than 174 lbs, they would be considered obese. Having too much body weight for your height is associated with an increased risk for heart disease, high blood pressure, type 2 diabetes, and even certain cancers, the NHLBI notes. RELATED: How Your BMI Can Affect Your Health and Wellness

How Plenity Works to Help Some People With Weight Loss

Although Plenity comes in the form of small capsule, the FDA has granted it clearance as a medical device rather than a pharmaceutical drug. That’s because the body doesn’t absorb the gelatin capsule, which contains hydrogel particles made from cellulose and citric acid. According to a series of tweets from the FDA, the particles simply absorb water and pass through the gastrointestinal system. The gel pieces have the firmness of vegetables once they reach the stomach and contain no calories. People take Plenity capsules 20 to 30 minutes before eating. “This drug appears to improve satiety in patients that have obesity,” says Stanford. “The patient will feel full quicker when eating a meal, which can likely lead to decreased food consumption and lower weight status,” she says. Once Plenity reaches the large intestine, it loses its three-dimensional structure and most of its absorption capacity. The released water is reabsorbed in the large intestine and then the remaining cellulosic material comes out when the person has a bowel movement. RELATED: 9 Hard Truths About Weight Loss That Can Help You Slim Down

How Much Weight Did People Lose in Previous Studies on Plenity?

The FDA based its approval of Plenity on the success of the aforementioned Obesity research, called the GLOW study. In the randomized, double-blind, and placebo-controlled study, 324 people completed the 24-week trial, with 172 participants randomly assigned to take Plenity and 152 randomly assigned to a placebo. Participants were 84 percent white and 56 percent female, and were between ages 22 and 65, with the average person being about 48 years old. Participants’ BMIs were between 27 and 40. Subjects took three capsules of Plenity or placebo with 500 milliliters of water 20 to 30 minutes before lunch and dinner. Researchers instructed participants to eat a diet with 300 calories below their calculated energy requirement with 45 to 50 percent of their calorie intake from carbohydrates, 30 percent from fat, and 20 to 25 percent from protein. Participants also exercised at a moderate intensity (such as walking or lightly biking) for 30 minutes every day. At the end of the trial, 59 percent of adults in the treatment group lost 5 percent or more of their total body weight, compared with 42 percent of the placebo group. Further analysis of the data published by Gelisis, the maker of Plenity, placed the participants into two groups: responders and nonresponders. The responders represented about 6 out of 10 people who took Plenity, and they lost an average of 10 percent of their total body weight (about 22 lbs) and nearly 4 inches from their waists. The nonresponders lost an average of only 1 percent of their total body weight (about 2 lbs). RELATED: 14 Diet and Weight Loss Mistakes — and How to Avoid Them Twenty-seven percent of the Plenity group were classified as super-responders, compared with 15 percent of the placebo group. These people lost an average of about 14 percent of their total body weight, or about 30 lbs. The investigators noted there was a clear and early separation between responders and non-responders. A weight loss of at least 3 percent as early as after eight weeks of treatment predicted clinically meaningful weight loss at six months. “Early prediction of response to therapy could allow more efficient use of resources and provide a key treatment milestone for clinicians and patients,” according to the paper. The study also showed that nearly one-half of the adults with prediabetes or people who had never had diabetes treatment were super-responders. These individuals, who typically face greater challenges to lose weight, had 6 times greater odds of being super-responders, compared with placebo, researchers reported. RELATED: 5 Bad Habits That May Increase Your Risk of Prediabetes

What Weight Loss Seekers Should Know About the Safety and Side Effects of Plenity

There were no serious adverse events and the FDA granted the product a “non-significant risk” (NSR) determination, per the GLOW study. But according to the FDA, Plenity can cause certain side effects, the most common of which are diarrhea, bloating, infrequent bowel movements, flatulence, and abdominal pain. The control group also had these side effects but at a lower rate. “Overall, it does have what appears to be a good safety profile and wide scale application to this patient population,” says Stanford. According to the makers of Plenity, there will be a targeted U.S. launch at the end of this year with the intent that the product will be widely available throughout the country by prescription in 2020.