US regulators have now approved Novo Nordisk’s obesity drug Saxenda (liraglutide 3mg), a higher dose form of its diabetes blockbuster Victoza (liraglutide 1.2mg and 1.8mg), to help patients lose weight alongside diet and exercise.

The US Food and Drug Administration has issued a green light for the glucagon-like peptide-1 receptor agonist in adults with a body mass index of 30 and above, or 27 in those with at least one weight-related condition such as hypertension or type II diabetes.

Approval came on the back of clinical data showing that patients had an average weight loss of 4.5% from baseline compared to treatment with a placebo at one year, and that 62% given the drug lost at least 5% of their body weight versus 34% of the control group. 

On the safety side, Saxenda has been approved with a Risk Evaluation and Mitigation Strategy and comes with a boxed warning that tumours of the thyroid gland have been observed in rodent studies (whether the drug causes these in humans is unknown). Regulators have also stipulated that Saxenda should not be used in patients with a personal or family history of medullary thyroid carcinoma or in those with multiple endocrine neoplasia syndrome type 2, as they are predisposed to MTC.

The FDA has requested that Novo carries out a suite of post-marketing studies: to evaluate dosing, safety, and efficacy in paediatric patients; to assess potential effects on growth, sexual maturation, and central nervous system development and function in immature rats; a 15-year-plus MTC case registry to identify any increase in MTC incidence related to Saxenda; and an evaluation of the potential risk of breast cancer. Cardiovascular safety is already being investigated in an ongoing outcomes trial.