Tesofensine (NS2330) is a serotonin–noradrenaline–dopamine reuptake inhibitor from the phenyltropane family of drugs, which is being developed for the treatment of obesity. The right to develop and market tesofensine is held by NeuroSearch, a Danish pharmaceutical company.

Tesofensine was originally investigated for the treatment of Alzheimer's disease and Parkinson's disease, and was subsequently dropped from development for these applications after early trial results showed limited efficacy for treatment of these diseases. However, weight loss was consistently reported as an adverse event in the original studies, especially in overweight or obese patients. Therefore, it was decided to pursue development of tesofensine for the treatment of obesity.

Tesofensine primarily acts as an appetite suppressant, but possibly also acts by increasing resting energy expenditure.Phase 2 trials for the treatment of obesity have been successfully completed.

Tesofensine has a long half-life of about 9 days (220 h) and is mainly metabolized by cytochrome P4503A4 (CYP3A4) to the N-desmethyl-metabolite NS2360. NS2360 is the only metabolite detectable in human plasma. It has a longer half-life than tesofensine, i.e. approximately 16 days (374 h) in humans, and has an exposure of 31–34% of the parent compound at steady state. In vivo data indicate that NS2360 is responsible for approximately 6% of the activity of tesofensine. As in animals, the kidney appears to play only a minor role in the clearance of tesofensine in humans (about 15–20%).