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NTX/PBO-B

Alkermes, Inc. · Phase 3 active Small molecule

NTX/PBO-B is a combination of naltrexone (an opioid antagonist) and bupropion (an antidepressant) designed to reduce appetite and promote weight loss.

NTX/PBO-B is a combination of naltrexone (an opioid antagonist) and bupropion (an antidepressant) designed to reduce appetite and promote weight loss. Used for Chronic weight management in obese or overweight adults with weight-related comorbidities.

At a glance

Generic nameNTX/PBO-B
SponsorAlkermes, Inc.
Drug classCombination antiobesity agent (opioid antagonist + antidepressant)
TargetOpioid receptors (naltrexone); norepinephrine and dopamine transporters (bupropion)
ModalitySmall molecule
Therapeutic areaObesity / Metabolic Disease
PhasePhase 3

Mechanism of action

Naltrexone blocks opioid receptors in the hypothalamus, removing tonic inhibition of pro-opiomelanocortin (POMC) neurons that regulate satiety. Bupropion, a norepinephrine-dopamine reuptake inhibitor, enhances the activity of these POMC neurons. Together, the combination increases energy expenditure and decreases hunger, leading to sustained weight reduction.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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