Last reviewed · How we verify
NTX/BUP
NTX/BUP is a Opioid agonist-antagonist combination Small molecule drug developed by Alkermes, Inc.. It is currently in Phase 3 development for Opioid use disorder (maintenance treatment).
NTX/BUP is a fixed-dose combination of naltrexone (an opioid antagonist) and buprenorphine (a partial opioid agonist) that reduces opioid cravings and withdrawal symptoms while blocking euphoric effects of additional opioid use.
NTX/BUP is a fixed-dose combination of naltrexone (an opioid antagonist) and buprenorphine (a partial opioid agonist) that reduces opioid cravings and withdrawal symptoms while blocking euphoric effects of additional opioid use. Used for Opioid use disorder (maintenance treatment).
-
Baseline phase 3 → approval rate
+58.3pp
Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas). -
CNS / neurology attrition
-3.0pp
CNS drugs have historically high Phase 3 failure rates (notably in Alzheimer disease + major depression).
| Regulator | Country | Likely year | Lag vs FDA |
|---|---|---|---|
| FDA | US | 2028–2030 | — |
| EMA | EU | 2029–2031 | +0.7 yr |
| MHRA | GB | 2029–2031 | +0.7 yr |
| Health Canada | CA | 2029–2032 | +0.9 yr |
| TGA | AU | 2029–2032 | +1.2 yr |
| PMDA | JP | 2029–2032 | +1.5 yr |
| NMPA | CN | 2030–2033 | +2.3 yr |
| MFDS | KR | 2029–2032 | +1.4 yr |
| CDSCO | IN | 2029–2033 | +1.8 yr |
| ANVISA | BR | 2030–2033 | +2.3 yr |
Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).
Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.
At a glance
| Generic name | NTX/BUP |
|---|---|
| Sponsor | Alkermes, Inc. |
| Drug class | Opioid agonist-antagonist combination |
| Target | Mu-opioid receptor (μ-OR) |
| Modality | Small molecule |
| Therapeutic area | Psychiatry / Addiction Medicine |
| Phase | Phase 3 |
Mechanism of action
Buprenorphine acts as a partial agonist at mu-opioid receptors, providing sufficient opioid activity to prevent withdrawal and reduce cravings, while naltrexone competitively blocks opioid receptors to prevent euphoria from additional opioid use. The combination is designed to improve treatment adherence and reduce the abuse potential compared to buprenorphine alone by discouraging attempts to augment the effect with additional opioids.
Approved indications
- Opioid use disorder (maintenance treatment)
Common side effects
- Headache
- Nausea
- Constipation
- Insomnia
- Withdrawal symptoms (if inadequately dosed)
Key clinical trials
- Trial of Naltrexone/Bupropion for the Treatment of Methamphetamine Use Disorder (PHASE3)
- Optimizing Retention, Duration and Discontinuation Strategies for Opioid Use Disorder Pharmacotherapy (RDD) (PHASE2)
- Extended-Release Naltrexone and Monthly Extended-Release Buprenorphine for Cocaine Use Disorder (CURB-2) (PHASE2)
- Improving Treatment Outcomes for Prescription Opioid Dependence (PHASE2, PHASE3)
- Buprenorphine/Naloxone Stabilization and Induction Onto Injection Naltrexone (PHASE2, PHASE3)
- Naltrexone for Use in Conjunction With Buprenorphine in Adults With Opioid Use Disorder Prior to First Dose of VIVITROL® (Naltrexone for Extended-Release Injectable Suspension) (PHASE3)
- Evaluating Naltrexone for Use in Conjunction With Buprenorphine in Adults With Opioid Use Disorder Transitioning From Buprenorphine Maintenance Prior to First Dose of VIVITROL (PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- NTX/BUP CI brief — competitive landscape report
- NTX/BUP updates RSS · CI watch RSS
- Alkermes, Inc. portfolio CI
Frequently asked questions about NTX/BUP
What is NTX/BUP?
How does NTX/BUP work?
What is NTX/BUP used for?
Who makes NTX/BUP?
What drug class is NTX/BUP in?
What development phase is NTX/BUP in?
What are the side effects of NTX/BUP?
What does NTX/BUP target?
Related
- Drug class: All Opioid agonist-antagonist combination drugs
- Target: All drugs targeting Mu-opioid receptor (μ-OR)
- Manufacturer: Alkermes, Inc. — full pipeline
- Therapeutic area: All drugs in Psychiatry / Addiction Medicine
- Indication: Drugs for Opioid use disorder (maintenance treatment)
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing