Library / Weight and metabolic

Tesofensine

Also known as NS2330, Nupenta, Tesomet (with metoprolol)

Human trials

Not a peptide: an oral small molecule that blocks reuptake of serotonin, noradrenaline and dopamine. Originally studied for Alzheimer and Parkinson disease, then for obesity in phase 2 and 3 trials.

Not an approved medicine. Tesofensine is not an approved medicine for this use in Australia or the United States. This page summarises published research for information only. It is not a recommendation to use Tesofensine, and VialOwl does not sell or supply it.

Background

Oral small molecule (NS2330), not a peptide, developed by the Danish company NeuroSearch. It was first tested for Parkinson and Alzheimer disease, where weight loss was noticed, and was then studied for obesity.

How it is thought to work

Blocks the reuptake of three brain chemical messengers: noradrenaline, dopamine and serotonin. This reduces appetite and may raise energy use, similar in concept to older weight loss stimulants.

What is claimed, and the evidence

Claim	Evidence	Notes
Weight loss in obesity	Human trials	Phase 2 trial (203 people): 4.5% to 10.6% weight loss over 24 weeks versus 2% with diet and placebo; phase 3 confirmation not found on PubMed. Not approved by TGA, FDA or EMA.
Treats Parkinson disease	Human trials Not supported	Randomised trial in early Parkinson disease showed no significant benefit over placebo.
Treats Alzheimer disease	Human trials Not supported	Studied in randomised trials; development for this use did not proceed.
Weight loss in hypothalamic obesity (combined with metoprolol as Tesomet)	Human trials	Randomised trial of 21 adults: about 6% more weight loss than placebo over 24 weeks; not approved.

Side effects

Effect	How often	Notes
Dry mouth	Common	Most common in obesity and Parkinson trials.
Insomnia	Common	Common in trials.
Nausea, constipation and diarrhoea	Common	Common in the phase 2 obesity trial.
Increased heart rate Serious	Common	About 7 beats per minute higher at 0.5 mg in the obesity trial; a concern given past heart safety problems with similar drugs.
Anxiety, sleep disturbance and headache	Common	In the Tesomet trial sleep problems affected 50% versus 13% on placebo; one person stopped because of worsened anxiety.

Warnings

Not a peptide and not approved by the TGA, FDA or EMA.
Raises heart rate; long term cardiovascular safety has not been shown.
Unapproved products are not made to medicine standards and may be contaminated, underdosed, overdosed or contain a different substance from the label; the TGA warns that injected unapproved peptides carry risks including contamination, infection and local tissue damage.

Regulatory status

Australia: Not included on the ARTG (unapproved). Not specifically listed in the Poisons Standard (June 2026). Not verified whether captured by another Poisons Standard entry.
United States: Not FDA approved. Reported approved in Mexico in 2023 (Not verified with the Mexican regulator).

Sources

Also in Weight and metabolic

From the VialOwl library, reviewed 26 September 2026. For education and general information. It is not medical advice and not a recommendation to use Tesofensine.