Tesofensine is an investigational compound that has been studied for its potential in the treatment of obesity. It belongs to the class of serotonin-norepinephrine-dopamine reuptake inhibitors (SNDRI) and is thought to work by increasing levels of neurotransmitters that play a role in appetite regulation and energy expenditure. Tesofensine was initially developed as an antidepressant but gained attention due to its observed weight loss effects during clinical trials.