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XR-NTX 380 mg, intramuscular injection

University of Pennsylvania · FDA-approved active Small molecule

XR-NTX 380 mg, intramuscular injection is a Opioid receptor antagonist Small molecule drug developed by University of Pennsylvania. It is currently FDA-approved for Opioid use disorder (prevention of relapse and maintenance of abstinence). Also known as: Vivitrol naltrexone for extended-release injectable suspension.

XR-NTX 380 mg is an extended-release formulation of naltrexone that blocks opioid receptors to prevent opioid use and reduce cravings in opioid use disorder.

XR-NTX 380 mg is an extended-release formulation of naltrexone that blocks opioid receptors to prevent opioid use and reduce cravings in opioid use disorder. Used for Opioid use disorder (prevention of relapse and maintenance of abstinence).

At a glance

Generic nameXR-NTX 380 mg, intramuscular injection
Also known asVivitrol naltrexone for extended-release injectable suspension
SponsorUniversity of Pennsylvania
Drug classOpioid receptor antagonist
TargetMu opioid receptor (primary); delta and kappa opioid receptors
ModalitySmall molecule
Therapeutic areaPsychiatry / Addiction Medicine
PhaseFDA-approved

Mechanism of action

Naltrexone is a competitive opioid receptor antagonist that binds to mu, delta, and kappa opioid receptors with high affinity. The extended-release intramuscular formulation provides sustained drug delivery over approximately one month, maintaining therapeutic opioid receptor blockade and reducing the reinforcing effects of opioid use. This mechanism helps prevent relapse and supports abstinence in patients with opioid use disorder.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

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

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Frequently asked questions about XR-NTX 380 mg, intramuscular injection

What is XR-NTX 380 mg, intramuscular injection?

XR-NTX 380 mg, intramuscular injection is a Opioid receptor antagonist drug developed by University of Pennsylvania, indicated for Opioid use disorder (prevention of relapse and maintenance of abstinence).

How does XR-NTX 380 mg, intramuscular injection work?

XR-NTX 380 mg is an extended-release formulation of naltrexone that blocks opioid receptors to prevent opioid use and reduce cravings in opioid use disorder.

What is XR-NTX 380 mg, intramuscular injection used for?

XR-NTX 380 mg, intramuscular injection is indicated for Opioid use disorder (prevention of relapse and maintenance of abstinence).

Who makes XR-NTX 380 mg, intramuscular injection?

XR-NTX 380 mg, intramuscular injection is developed and marketed by University of Pennsylvania (see full University of Pennsylvania pipeline at /company/university-of-pennsylvania).

Is XR-NTX 380 mg, intramuscular injection also known as anything else?

XR-NTX 380 mg, intramuscular injection is also known as Vivitrol naltrexone for extended-release injectable suspension.

What drug class is XR-NTX 380 mg, intramuscular injection in?

XR-NTX 380 mg, intramuscular injection belongs to the Opioid receptor antagonist class. See all Opioid receptor antagonist drugs at /class/opioid-receptor-antagonist.

What development phase is XR-NTX 380 mg, intramuscular injection in?

XR-NTX 380 mg, intramuscular injection is FDA-approved (marketed).

What are the side effects of XR-NTX 380 mg, intramuscular injection?

Common side effects of XR-NTX 380 mg, intramuscular injection include Injection site reactions (pain, erythema, induration), Nausea, Headache, Insomnia, Anxiety, Hepatotoxicity (elevated liver enzymes).

What does XR-NTX 380 mg, intramuscular injection target?

XR-NTX 380 mg, intramuscular injection targets Mu opioid receptor (primary); delta and kappa opioid receptors and is a Opioid receptor antagonist.

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