New drug for obesity is important, but changing habits remains essential

The approval by Anvisa of Wegovy, the first injectable drug for weekly use for obesity, may be an important strategy in combating the condition in Brazil, experts point out. However, the adoption of other measures, such as healthy eating and physical activity, remain essential. The high value of the drug is also a cause for concern.

According to estimates by the World Obesity Federation, an international organization dedicated to the reduction, prevention and treatment of obesity, in 2030 Brazil will have almost 30% of the adult population living with obesity. This is one of the highest rates in the world.

Therefore, the approval of the new medicine is considered a positive point to reduce the high number in Brazil. “Having a medicine that is safe and more effective than the old ones is in fact a breakthrough”, says Licio Velloso, professor of medicine at Unicamp (State University of Campinas) and coordinator of the Center for Research on Obesity and Comorbidities.

Clinical studies with more than 4,500 people worldwide found that the drug led to an average 17% reduction in body weight in patients over about 17 months. In contrast, those who used the placebo lost 2.4% of body weight.

Produced by Novo Nordisk, Wegovy is the trade name for semaglutide 2.4mg. Velloso explains that the substance was designed by genetic engineering to act on neurons associated with the feeling of satiety. The drug increases this perception even without eating anything or with a low diet.

“It’s as if this drug imitated the role that food intake would have. So, the individual ends up feeling as if he had eaten”, explains the professor. By causing this notion, the patient loses weight during the treatment.

Another substance with similar functioning is liraglutide. In Brazil, it already had authorization in cases of obesity. However, semaglutide has some advantages.

“It is a breakthrough because it has more power and is safer”, says Velloso. The professor mentions that semaglutide has a longer stay in the body. This makes the patient use the injection once a week – for liraglutide, this occurs daily. In addition, it provides a better feeling of satiety, which is related to greater weight loss.

Other medications

In addition to liraglutide and semaglutide, two other drugs are authorized to treat obesity in Brazil: orlistat and sibutramine. Velloso explains that the first two have more specific actions.

Orlistat inhibits an enzyme that we have in the intestine with the function of absorbing fat. When a person eats a fatty food and is taking orlistat, the medicine inhibits the enzyme and the fat is discarded in the stool. The problem is that this mechanism can cause diarrhea due to the fat coming out during defecation. “It is not a very comfortable medication, so much so that it is not used that much”, says Velloso.

Sibutramine, on the other hand, acts on the brain by reducing the desire to eat foods that give pleasure to the patient. The problem is that it is associated with side effects and is not recommended for people with heart disease. “This is very important because a large number of patients with obesity have cardiovascular diseases. So you eliminate a large number of people who cannot use sibutramine”, says Velloso.

“It won’t solve the problem”

Even if the approval of the new drug with a higher rate of effectiveness and safer is a positive point for the control of obesity, other actions are still necessary. Velloso says that the drug alone “will not solve the problem”, since the consumption of healthy and less caloric foods, combined with the practice of physical activity, are essential.

“Changes in habits are the basis of any type of health care for people with obesity”, says Paulo Miranda, president of Sbem (Brazilian Society of Endocrinology and Metabology). According to him, other actions, such as medication, come to help with other strategies.

Miranda also claims that it is necessary to incorporate new technologies into the SUS (Sistema Único de Saúde) so that medicines such as semaglutide are accessible to a larger portion of the population.

“We don’t have any pharmacological therapy available for the treatment of obesity inserted in the SUS. So, patients who depend on the SUS for their care and for the supply of medication are left unattended in this scenario.”

There are still no expectations for the drug to be submitted to Conitec (National Commission for the Incorporation of Technologies in the SUS) for availability in public health. Pharmaceutical Novo Nordisk also has no forecast of how much the drug will cost in Brazil. In the United States, where semaglutide is already sold, the list price is US$ 1,349 (about R$ 6,000).

For the value, Velloso says he believes that semaglutide will be restricted to the highest income population. But he believes the drug’s costs will come down, making it more affordable over time.

The Unicamp professor cites the case of liraglutide. According to him, in the beginning, the medicine cost between R$ 1,600 and R$ 1,700. In about five years, the drug’s price dropped, reaching a current average price of R$ 800 – about half of the price initially charged.