What benefits of Wegovy have been shown in studies?

Studies have shown that Wegovy is effective in helping people lose weight, with a significant proportion of them achieving at least a 5% weight reduction.

Three of the studies involved adults who had tried unsuccessfully to lose weight in the past and had a BMI of >30 kg/m2 or a BMI of >27 kg/m2 plus a weight-related health problem.

In the first of these, involving 1,961 people, people treated with Wegovy were able to lose on average 15% of their body weight after 68 weeks compared with a 2% loss of weight in people who had placebo (a dummy treatment). In addition, 84% of people in the Wegovy group were able to lose at least 5% of their weight compared with 31% of people in the placebo group.

In the second study, involving 611 people, those treated with Wegovy lost on average 16% of their body weight after 68 weeks compared with a 6% loss of weight in people who had placebo. Around 85% of people in the Wegovy group lost at least 5% of their weight compared with 48% of people in the placebo group. All participants in this study also received counselling to help them lose weight.

The third study, involving 902 people, looked at how the effects of Wegovy were maintained over the first 20 weeks. In this study, all participants had Wegovy for 20 weeks, after which some stopped having Wegovy and were given placebo instead. After 48 more weeks, those who continued on Wegovy lost a further 8% of their body weight while those on placebo regained 7% of theirs, indicating that people need to continue taking Wegovy in order not to regain weight.

A fourth study involved 1,210 adults with type 2 diabetes with a BMI of >27 kg/m2 and who had also tried unsuccessfully to lose weight in the past. After 68 weeks, those treated with Wegovy were able on average to lose 10% of their weight compared with a 3% loss in people who had placebo. In addition, 67% of people in the Wegovy group were able to lose at least 5% of their weight compared with 30% of people in the placebo group.