The drug semaglutide, offered commercially as Ozempic or Wegovy, is well-known for serving to individuals lose vital quantities of weight shortly. Now the U.S. Meals and Drug Administration has permitted Wegovy, the model of semaglutide at present prescribed for weight reduction, for stopping critical cardiovascular situations in sure people who find themselves at excessive threat.
The FDA’s March 8 announcement will permit medical doctors to prescribe Novo Nordisk’s Wegovy, which has a better most dose of semaglutide than Ozempic does, to people who find themselves obese or overweight and have had at the least one cardiovascular occasion similar to a coronary heart assault or stroke. “It opens up a complete new group of sufferers for us,” says Nicholas Marston, a heart specialist at Brigham and Ladies’s Hospital.
This is what we learn about semaglutide’s results on heart problems and the way it may work.
Who’s candidate for taking the drug to scale back cardiac threat?
The FDA’s approval expands using semaglutide to individuals with a BMI of 27 or larger (certified as obese or overweight) with a historical past of cardiac occasions. But it surely’s unknown whether or not the drug would work as nicely at stopping heart problems in individuals with decrease BMIs. And it nonetheless hasn’t been examined in individuals who could also be susceptible to heart problems however haven’t been recognized.
How efficient is semaglutide at stopping cardiovascular issues?
The FDA based mostly its choice on a 2023 trial referred to as Semaglutide Results on Cardiovascular Outcomes in Folks with Obese or Weight problems (SELECT), by which Novo Nordisk examined Wegovy in additional than 17,000 individuals. The individuals all had a physique mass index (BMI) of 27 or larger. However not like earlier trials of semaglutide, the SELECT individuals didn’t have a historical past of diabetes, the illness for which the drug was initially permitted in 2017.
The trial confirmed that individuals who took semaglutide misplaced nearly 10% of their physique weight on common in comparison with individuals who obtained a placebo. That they had a 20% decrease threat of coronary heart assaults and strokes in the midst of about three years, in addition to considerably decrease ldl cholesterol and blood stress.
In gentle of those findings, which have been revealed in November, the FDA’s choice to approve the drug for stopping coronary heart issues “wasn’t shocking in any respect,” says Joseph Wu, a heart specialist at Stanford College. He says the 20% discount in threat is spectacular. By comparability, a 2023 trial of one other new coronary heart drug, bempedoic acid, discovered a 13% discount in threat of coronary heart assaults and strokes over three years. Wegovy might be a part of the ranks of different efficient cardiovascular medicine, similar to beta blockers and statins.
How does the drug stop cardiac issues?
Basically, semaglutide is believed to trigger individuals to drop pounds by binding to a molecule on cell surfaces referred to as the GLP-1 receptor, the place it mimics a starvation hormone and slows the speed at which the abdomen empties. This reduces urge for food and causes individuals to eat much less, leading to speedy weight reduction.
However its results on the cardiovascular system are much less clear. “It is the $1-million query,” Wu says. Weight reduction in all probability accounts for almost all of the impact, he says. Researchers already know that, for people who find themselves obese, shedding 10% of 1’s physique weight considerably reduces the chance of heart problems and stroke, and it has different advantages similar to decreasing knee ache and shortness of breath.
It is doable that semaglutide can also be having one other impact, Wu and Marston say. The drug might bind to GLP-1 receptors or another goal immediately on the center or blood vessels and have an effect on their perform or scale back irritation that would injury the cardiovascular system. The SELECT trial discovered proof that the drug lowered blood stress, irritation (as measured by blood proteins made by the liver) and ldl cholesterol.
Determining how a lot of the impact is a results of weight reduction or an extra impact will doubtless be a analysis precedence sooner or later, Marston says. “We at all times like to know why one thing works.” Scientists will have the ability to check a few of these questions within the lab utilizing human cells or animal fashions to know semaglutide’s mechanism for stopping heart problems extra exactly. And the SELECT trial has given Novo Nordisk a large dataset that the corporate can mine for extra details about the drug’s results.
What are the uncomfortable side effects?
Semaglutide shouldn’t be a brand new drug, and its uncomfortable side effects and dangers are well-known. The commonest ones are gastrointestinal issues similar to nausea and constipation, which happen as a result of the drug slows gastric emptying.
However researchers have not but studied what is going to occur to cardiovascular threat if individuals cease taking the drug. Individuals who take semaglutide for weight reduction however discontinue it normally achieve the burden again shortly, which Wu says would doubtless improve their cardiovascular threat to what it was beforehand. “The primary message is: taking this remedy does not imply you not want to steer a wholesome way of life,” he says.
What do scientists nonetheless not learn about semaglutide and coronary heart illness?
Wu says it is nonetheless unclear whether or not shedding 10% of 1’s weight with out weight reduction medicine has a special impact on cardiovascular threat than shedding it with semaglutide; nobody has performed a head-to-head comparability. And he provides that the SELECT trial didn’t embrace many individuals from completely different races or genders. Greater than 70% have been male, and 84% have been white. As extra individuals start taking the drug for weight reduction, researchers might be able to assemble extra information to find out how nicely it really works in broader populations.
This text was first revealed at Scientific American. © ScientificAmerican.com. All rights reserved. Comply with on TikTok and Instagram, X and Fb.