Josefa García Barrado

In the treatment of obesity, maintaining weight loss is the most difficult phase. Two independent clinical trials published in Nature Medicine have adopted two different strategies to achieve this. The first is a phase 3b trial involving the GLP-1 drug orforglipron, administered orally on a daily basis for 52 weeks. This trial included 376 adults in the United States who had already completed 72 weeks of injectable treatment with tirzepatide or semaglutide. Almost 75% and 80% respectively of patients on each injectable drug maintained their weight loss. The second trial involved 90 obese adults from the Netherlands who followed a low-calorie diet for eight weeks and then received a daily supplement of the bacterium Akkermansia muciniphila for 24 weeks, alongside a healthy diet. Although those who received the supplement regained more than 13% of the weight initially lost, those who took the placebo regained almost 33%.

GLP-1 medicines for the treatment of obesity show considerable variability between individuals. Using data from 23andMe, scientists at this genetic testing company conducted genome-wide association studies in nearly 28,000 people treated with these drugs, analysing self-reported weight loss and adverse effects. Their findings, published in Nature, identified variations in two genes involved in gut hormone pathways that regulate appetite and digestion, although the authors caution that the effects of genetics appear to be modest.

Glucagon-like peptide-1 (GLP-1) receptor agonist drugs, used to control obesity and type 2 diabetes, are associated with changes in food purchasing in favour of healthier options. This result, published in the journal JAMA Network Open, was obtained by analysing nearly two million shopping receipts from more than 1,100 participants in Denmark. Those who started treatment with GLP-1 drugs began to make purchases with fewer calories, sugars, saturated fats and carbohydrates, along with a modest increase in protein content. A decrease in the purchase of ultra-processed foods was also observed.

An article published in Nature Medicine outlines the new framework for pharmacologically treating obesity and its complications established by the European Association for the Study of Obesity (EASO). The new guidelines establish semaglutide and tirzepatide as first-line treatment for this disease and most associated conditions. The team of authors, with Spanish participation, reviewed the scientific evidence on the effects of drugs on total weight loss and its complications and designed an algorithm to help medical personnel guide treatment, taking into account each patient's medical history and the action profiles of available medications.

The use of GLP-1 analog diabetes drugs-such as semaglutide, sold under the trade name Ozempic-is not linked to an increased risk of suicide, according to two studies published in JAMA Internal Medicine. The first, led by a U.S. team, analyzes data from more than 3,300 people who have participated in clinical trials. The second analyzes data from 124,517 users of these drugs in Sweden and Denmark, and compares them with an even larger group of people who used another type of diabetes medication.

A paper published today in the journal Science explores the potential of glucagon-like peptide-1 (GLP-1)-based drugs such as semaglutide to treat diseases beyond diabetes and obesity. For example, recent studies suggest that they could improve conditions ranging from depression to neurological disorders to cardiovascular and kidney disease.

The Spanish Agency of Medicines and Health Products (AEMPS) has announced that the anti-obesity drug Wegovy (semaglutide) will be available, with a doctor’s prescription, starting from May. It is the same active ingredient as Ozempic, but for patients without diabetes.