Context: Hypothalamic injury often leads to rapid, intractable weight gain causing hypothalamic obesity, which is associated with increased risk of cardiovascular and metabolic morbidity and mortality. There are no approved or effective pharmacological treatments for hypothalamic obesity, and conventional lifestyle management remains ineffective.

Objective: Investigate the safety and efficacy of Tesomet (0.5mg tesofensine/50mg metoprolol) in adults with hypothalamic obesity.

Methods: Twenty-one adults with hypothalamic obesity (16 females) were randomized to Tesomet (0.5mg/50mg) or placebo for 24 weeks. Patients also received diet/lifestyle counselling. The primary endpoint was safety; secondary endpoints included measures of body weight, appetite-scores, quality of life, and metabolic profile.

Results: Eighteen patients completed 24-weeks. Consent withdrawal, eligibility, and serious adverse events (SAE) unrelated to treatment resulted in dropouts. One patient experienced a Tesomet-related SAE of exacerbated pre-existing anxiety leading to treatment discontinuation. Tesomet-related adverse events were otherwise mostly mild, and included sleep disturbances (Tesomet 50%, Placebo 13%), dry mouth (Tesomet 43%, Placebo 0%), and headache (Tesomet 36%, Placebo 0%). No significant differences in heart rate or blood pressure were observed between groups. Compared to placebo, Tesomet resulted in additional mean (95% CI) weight change of -6.3% ([-11.3; -1.3]; P = 0.017), increased the number of patients achieving ≥5% weight loss (Tesomet 8/13, Placebo 1/8; P = 0.046), and tended to augment the reduction in waist circumference by 5.7cm ([-0.1; 11.5]; P = 0.054).

Conclusion: Tesomet was well-tolerated, did not affect heart rate or blood pressure, and resulted in significant reductions in body weight compared to placebo in adults with hypothalamic obesity.