What is a clinical trial?

A clinical trial is a research study involving human participants designed to evaluate medical interventions — such as drugs, devices, or behavioral strategies. Trials follow a structured protocol and are registered on ClinicalTrials.gov. They progress through phases: Phase 1 (safety), Phase 2 (efficacy), Phase 3 (large-scale comparison), and Phase 4 (post-market surveillance).

How do I find clinical trials I'm eligible for?

You can search ClinicalTrials.gov or use ClinicalMetric to filter by condition, phase, or location. Each trial listing includes eligibility criteria such as age range, sex, diagnosis, and prior treatment history. Contact the study team directly or ask your physician to refer you to a relevant trial.

Are clinical trials safe to participate in?

Clinical trials are conducted under strict ethical and regulatory oversight, including IRB approval and FDA regulation in the US. All participants must give informed consent after reviewing potential risks and benefits. Phase 1 trials carry more uncertainty, while Phase 3 trials involve interventions with an established safety profile. Participation is always voluntary and you may withdraw at any time.

What are the phases of clinical trials?

Clinical trials progress through four main phases. Phase 1 tests safety and dosing in a small group (20–80 people). Phase 2 evaluates efficacy and side effects in a larger group (100–300). Phase 3 compares the intervention against standard treatments in thousands of participants. Phase 4 occurs after approval and monitors long-term effects in the general population.

Do participants get paid for joining clinical trials?

Many clinical trials offer compensation for time and travel expenses, though payment structures vary widely by study. Compensation is not intended to be coercive. Some trials also cover treatment costs for participants. Always review the consent form carefully and ask the study coordinator about any financial considerations before enrolling.

Addiction and Substance Use Disorder Clinical Trials 2026: Opioid, Alcohol, and New Treatments

Medical Notice

This article is for informational purposes only and does not constitute medical advice. Substance use disorder treatment should be supervised by a qualified healthcare provider. If you or someone you know is experiencing a substance use crisis, contact SAMHSA's National Helpline at 1-800-662-4357 (free, confidential, 24/7).

Summary

Substance use disorders (SUDs) affect over 48 million Americans and cost the U.S. economy over $600 billion annually — yet treatment remains dramatically under-utilized, with fewer than 20% of people with SUD receiving any treatment in a given year. In 2026, a wave of novel therapeutic approaches is entering clinical trials: psilocybin and MDMA are advancing through Phase 2 and Phase 3 trials for alcohol use disorder and PTSD-related substance use; GLP-1 receptor agonists like semaglutide and liraglutide are showing unexpected ability to reduce cravings for alcohol and opioids; and ibogaine derivatives are being evaluated in structured clinical settings following striking results in veterans with treatment-resistant addiction. NIDA's Clinical Trials Network (CTN) continues running pragmatic trials across community treatment programs. This guide covers the most important SUD trials recruiting in 2026 and how to connect with them.

NIDA Clinical Trials Network (CTN)

The National Institute on Drug Abuse (NIDA) funds the Clinical Trials Network, a system of approximately 16 research nodes across the U.S. that conduct trials in real-world community treatment settings — not just academic medical centers. This is significant because CTN trials recruit people who are already seeking treatment, making them more accessible than academic trials that often require patients to travel to specialized centers.

Active CTN trials in 2026 include comparisons of buprenorphine formulations, low-dose naltrexone augmentation, telehealth-delivered MOUD, and contingency management for stimulant use disorder.
CTN-0094 (INSPIRE): Evaluating extended-release buprenorphine (Sublocade) versus daily sublingual buprenorphine for opioid use disorder treatment — addresses adherence and diversion concerns with depot formulations.
CTN-0099: Studying liraglutide (a GLP-1 agonist) for reducing alcohol use in alcohol use disorder — recruiting adults who drink heavily and are motivated to reduce or stop drinking.
Finding CTN trials: Visit drugabuse.gov/researchers/research-resources/nida-clinical-trials-network or search ClinicalTrials.gov for "NIDA CTN" as the sponsor.

GLP-1 Agonists: An Unexpected Addiction Treatment

One of the most surprising findings in addiction medicine in recent years is that GLP-1 receptor agonists — the class of drugs including semaglutide (Ozempic/Wegovy) and liraglutide (Victoza/Saxenda), originally developed for diabetes and obesity — appear to reduce cravings for alcohol, opioids, nicotine, and other substances. Animal studies showed dramatic reductions in self-administration; observational studies in humans are confirming the signal.

Semaglutide for alcohol use disorder: Phase 2 trials at multiple academic centers (NCT05895643 and others) testing 0.5–1mg weekly injections in people with moderate-to-severe AUD; primary outcomes are reduction in heavy drinking days and alcohol cravings.
Semaglutide for opioid use disorder: Phase 2 trials evaluating semaglutide as an adjunct to buprenorphine — testing whether it reduces residual cravings and relapse risk in patients already on MOUD.
Mechanism: GLP-1 receptors in the mesolimbic reward system (nucleus accumbens, VTA) appear to modulate dopamine signaling triggered by addictive substances; reducing the reward value of the substance reduces craving and use.
Eligibility typically requires: Adults 18+ with AUD or OUD diagnosis (DSM-5 criteria), absence of contraindications to GLP-1 agonists (pancreatitis history, thyroid cancer risk), not currently pregnant.

Psilocybin for Alcohol Use Disorder

After a landmark Johns Hopkins study (Davis et al., 2021) showed psilocybin therapy producing large reductions in heavy drinking, multiple Phase 2 and Phase 3 trials are now evaluating psilocybin-assisted therapy (PAT) for alcohol use disorder (AUD). This is among the most active areas of psychedelic medicine research in 2026.

NIAAA-funded Phase 2 trials: Multiple university centers (Yale, UCSF, UNC, Ohio State) are running Phase 2 psilocybin + psychotherapy trials for AUD in 2026; comparing different dose regimens and therapy protocols.
USONA Institute Phase 3: Planning a Phase 3 registration trial for psilocybin in AUD; protocol in development with FDA IND granted.
How sessions work: Typically 2–3 high-dose psilocybin sessions (25–30mg) with trained therapists present; preceded by preparatory sessions and followed by integration therapy; total commitment 3–4 months.
Exclusion criteria: Personal or family history of psychosis, bipolar I disorder, or schizophrenia; use of lithium or MAOIs; severe cardiovascular disease. Screening is thorough.

Ibogaine for Opioid Use Disorder

Ibogaine, a psychoactive compound derived from the West African Tabernanthe iboga plant, has shown striking case series results in opioid use disorder — reportedly interrupting withdrawal symptoms and cravings for extended periods after a single dose. A landmark 2023 Nature Medicine study of 30 Special Operations veterans showed ibogaine (with magnesium co-administration for cardiac safety) produced significant reductions in PTSD, depression, and alcohol use.

Phase 2 trial (NCT05765981): MAPS-sponsored study evaluating ibogaine + magnesium for treatment-resistant opioid use disorder; recruiting veterans and non-veterans at clinical sites in Canada and Europe (ibogaine remains Schedule I in the U.S.).
Noribogaine (TBX-002): An ibogaine metabolite with a longer half-life and potentially improved cardiac safety profile; Phase 1 studies underway evaluating dose range and QTc prolongation management.
Cardiac monitoring: Ibogaine's primary safety concern is QT prolongation leading to cardiac arrhythmia; all clinical trials require baseline ECG, cardiology clearance, and continuous cardiac monitoring during the session.

Opioid Use Disorder: MOUD Optimization Trials

Medications for opioid use disorder (MOUD) — buprenorphine, methadone, and naltrexone — are the evidence-based standard of care, yet many patients have suboptimal outcomes due to adherence barriers, dose adequacy, or co-occurring conditions. Active 2026 trials address these gaps:

X:BOT extended study: Follow-up to the original X:BOT trial comparing XR-naltrexone vs buprenorphine; extended 12-month follow-up outcomes are being analyzed to understand long-term relapse patterns.
Low-dose buprenorphine induction (Bernese protocol): Allows patients on fentanyl to start buprenorphine without precipitated withdrawal; pragmatic trials validating the protocol in emergency department and outpatient settings.
Contingency management for stimulant use: SAMHSA's Contingency Management Learning Collaborative and clinical trials testing financial incentives (up to $600 in prizes) for stimulant-negative urine screens; highly effective but previously restricted by federal guidelines now being revised.

How to Find Addiction Clinical Trials in 2026

ClinicalTrials.gov: Search your substance (e.g., "alcohol use disorder" or "opioid use disorder") + "recruiting" + your state. Many trials offer compensation and cover transportation costs.
NIDA's website: drugabuse.gov has a trials finder and lists of CTN sites by state — CTN sites are embedded in community treatment programs, making participation easier than academic center trials.
SAMHSA treatment locator: findtreatment.gov identifies community treatment programs — many serve as CTN research sites and have coordinators who can discuss both standard care and trial options.
Psychedelic trial registries: MAPS (maps.org), Usona Institute, and Multidisciplinary Association for Psychedelic Studies maintain their own trial registries for psilocybin, MDMA, and ibogaine studies.

End of Guide // ClinicalMetric Intelligence — CM-INS-073