Novo Nordisk will sell a less expensive one-month supply of Wegovy for patients who previously took compounded versions of the medication.

After years of easily available, cheap copies of Eli Lilly's and Novo Nordisk's highly effective weight-loss drugs, some U.S. patients say they are unwilling to pay more and are pursuing alternatives to get around the regulatory deadline for compounding pharmacies to stop making them.

Those who take tirzepatide, the drug sold as Zepbound and Mounjaro, could lose more weight than those who take semaglutide, known as Ozempic and Wegovy, according to new research.