Cigna will cap out-of-pocket costs at $200 per month for patients using the weight-loss drugs Wegovy and Zepbound through an add-on to its pharmacy benefit management plans, the company announced on Wednesday.

A new study shows that people Zepbound lost about 50% more weight than those using Wegovy. It was the first head-to-head trial of the blockbuster weight-loss medications.

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