For millions of people taking weight loss drugs, the next breakthrough may not be more weight loss.It may be fewer injections.Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.Pfizer and Amgen are developing monthly GLP-1 shots — a departure from injections like Wegovy and Zepbound, which are taken weekly.The goal, the drugmakers say, is to make weight loss drugs more convenient and easier to stick with.“Whether it’s a daily pill, a weekly injection or even a monthly injection, the more frequently a medication must be taken, the more opportunities there are to miss doses or stop treatment altogether,” said Dr.
Christopher McGowan, a gastroenterologist who runs a weight loss clinic in Cary, North Carolina.Dr.John Buse, an endocrinologist at the University of North Carolina School of Medicine, said patients “really like the idea” of a monthly GLP-1 shot.“The straight-up benefit of the once-monthly dose is you get 12 injections a year versus 52 a year,” said Buse, who worked on the trial of Pfizer’s monthly shot.All GLP-1 drugs start with the same premise: They’re molecules that bind to the GLP-1 receptor, setting off a cascade of signals in the body that regulate blood sugar and feelings of hunger.
That’s how semaglutide, the ingredient in Ozempic and Wegovy, works.But drugmakers soon began expanding what GLP-1s could do.
Tirzepatide, the ingredient in Mounjaro and Zepbound, binds to a second receptor, called GIP.Eli Lilly’s experimental drug, retatrutide, adds in a third.In all of these cases, the body begins to break down the active ingredients after about seven days, so weekly doses are needed to maintain the effects.
To make monthly dosing possible, Pfizer and Amgen had to engineer new drugs that remain active in the body far longer.Pfizer’s experimental drug berobenatide works by staying attached longer to a protein in the blood called albumin, which protects the molecule from bein...