Neuropathic PainPhase 2CANNCT05351801
Proof of Concept Trial of Cannabis Derivatives in Neuropathic Pain
A Phase 2 study testing THC (Syndros), CBD (Epidolex) and THC + CBD (Nabiximols) in people with Neuropathic Pain and Peripheral Neuropathic Pain, run by VA Office of Research and Development at 6 sites in United States.
Trial summary
Chronic neuropathic pain (CNP) is disabling. Research on frontline treatments for CNP, shows inconsistent outcomes and dissatisfaction among Veterans. Veterans and clinicians have shown significant interest in cannabis derivatives (THC, CBD) for neuropathic pain control, but there are no well-controlled trials guiding… Read more about this study
- Who is it for?
- Ages 21 years and older
- Conditions the study is for
- Neuropathic Pain, Peripheral Neuropathic Pain
- What is being tested?
- THC (Syndros), CBD (Epidolex) and THC + CBD (Nabiximols)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 320 participants
- Where
- 6 sitesUnited States
- Study dates
- 21 Jun 2023to 31 May 2029
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Able to provide written consent
- Veterans 21 years and older at the date of screening
- Meet diagnostic criteria for neuropathic pain as defined by the Neuropathic Pain Special Interest Group of the International Association for the Study of Pain (NeuPSIG)
- Meet criteria for persistent, high-impact pain criteria.
- Presence of allodynia confirmed by one of the screening dynamic brush tests
- women of childbearing potential who agree to abide by contraceptive requirements
Who cannot join
- Actively engaged in or planning to enter a program of non-pharmacological invasive intervention for pain at the time of enrollment
- Peripheral neuropathy is not a primary source of neuropathic pain
- Hypersensitivity to THC, CBD, or THC/CBD
- Self-report of cannabis use during screening phase confirmed by positive urine toxicology for THC-COOH as measured and resulted at visit 5 before randomization
- Unwilling to refrain from using cannabis or cannabis-based products through the entire duration of the study
- Diagnosis of DSM-5 Cannabis Use Disorder in the past 6 months
Show all 14Show fewer
- Current DSM-5 diagnosis of cannabis use disorder, substance use disorder or serious psychiatric disorders
- Actual change or intent to change is greater than a 20% change (increase or decrease) in any other medication for pain or non-pharmacological treatment from 4 weeks before the screening appointment until completion of study (i.e., visit 13)
- Opioid doses > 400 mg MME (morphine milligram equivalent)
- Women who are pregnant or breastfeeding, or who intend to become pregnant in the 12 weeks from enrollment
- Any current unstable or concerning medical condition that would place the patient at increased risk, including hepatic, respiratory, immunological, cardiovascular, endocrine, or renal disease, or in the opinion of the investigator, prevents adherence with the protocol
- Need for immediate psychiatric hospitalization
- Enrolled in a medical marijuana program
- Federal employee
Trial locations and contacts
6 sites in 1 country. Contact the study team or a site near you to ask about taking part.
6 sites in 1 country
United States6 sites, 4 recruiting
- Recruiting
Providence VA Medical Center, Providence, RI
Providence, Rhode Island, 02908-4734
Jane Metrik, PhD, 401-273-7100 ext. 3400, jane.metrik@va.gov
- Recruiting
South Texas Health Care System, San Antonio, TX
San Antonio, Texas, 78229-4404
Muhammad Baig, MD, 210-617-5300 ext. 18244, muhammad.baig@va.gov
- Recruiting
VA San Diego Healthcare System, San Diego, CA
San Diego, California, 92161-0002
Albert Leung, MD, 858-642-3029, albert.leung@va.gov
- Terminated
VA Puget Sound Health Care System Seattle Division, Seattle, WA
Seattle, Washington, 98108-1532
- Recruiting
VA Connecticut Healthcare System West Haven Campus, West Haven, CT
West Haven, Connecticut, 06516-2770
Deepak D'Souza, MD MBBS, (203) 932-5711 ext. 2594, Deepak.DSouza@va.gov
Deepak D'Souza, MD MBBS
- Active, not recruiting
VA Greater Los Angeles Healthcare System, West Los Angeles, CA
West Los Angeles, California, 90073-1003
About this study
Chronic neuropathic pain (CNP) is disabling. Research on frontline treatments for CNP, shows inconsistent outcomes and dissatisfaction among Veterans. Veterans and clinicians have shown significant interest in cannabis derivatives (THC, CBD) for neuropathic pain control, but there are no well-controlled trials guiding expectations for benefit and adverse outcomes associated with cannabis for CNP. Because Veterans are likely to present with pain and pain-related polymorbidity significantly differing from that of civilians, a well-structured clinical trial of cannabinoids for Veterans with CNP is vital.
Read the detailed description
Chronic pain is a significant burden to United States Veterans and is a particular concern for Veterans. One of the causes of pain is chronic neuropathic pain (CNP). Frontline treatment for CNP, show inconsistent outcomes and have significant side effects. The ongoing opioid crisis has led to significant interest in safe and effective alternatives for pain control, and there is a significant need for research on desirable options for pain control that are likely to improve treatment adherence and outcomes. Veterans groups and Veterans Affairs clinicians have expressed significant interest in cannabis and its principal constituents (delta-9-tetrahydrocannabinol, THC; cannabidiol, CBD) for pain management, but the extant research describing the potential risks and benefits of cannabis for pain is weak. This randomized trial was developed as a proof of concept study to determine if cannabis constituents (THC, CBD, and THC+CBD) are superior to placebo in reducing pain in Veterans with CNP. The study is to recruit a sample of 320 adult Veterans who meet diagnostic criteria for high-impact CNP, are on stable treatment(s) for CNP, are not current cannabis users and who do not meet diagnostic criteria for Cannabis Use Disorder. This randomized phase II, 4-arm clinical trial aims to determine if cannabis constituents (THC, CBD) or their combination (THC+CBD) are superior to placebo in reducing pain in Veterans with CNP. This trial will offer the first evidence describing the potential benefits and adverse effects of cannabinoids for CNP in Veterans.
- Conditions
- Neuropathic Pain, Peripheral Neuropathic Pain
- Being tested
- THC (Syndros), CBD (Epidolex), THC + CBD (Nabiximols), Placebo
- Medical subject headings
- Neuralgia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
THC (Syndros)Drug
Participants will receive a target dose of 10mg per day of THC (Syndros).
CBD (Epidolex)Drug
Participants will receive a target dose of 800 mg per day of CBD (Epidolex).
THC + CBD (Nabiximols)Drug
Participants will receive a target dose of 10.8 mg / 10 mg per day of THC + CBD (Nabiximols).
PlaceboDrug
Placebo
| Study group | Role | What they receive |
|---|---|---|
| THC (Syndros) | Active comparator | Target dose of 10mg per day. Receives: Drug: THC (Syndros); Drug: Placebo |
| CBD (Epidolex) | Active comparator | Target dose of 800 mg per day. Receives: Drug: CBD (Epidolex); Drug: Placebo |
| THC + CBD (Nabiximols) | Active comparator | Target dose of 10.8 mg / 10 mg per day. Receives: Drug: THC + CBD (Nabiximols); Drug: Placebo |
| Placebo | Placebo comparator | Identical in appearance to the three active comparators. Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
To compare the short-term efficacy of THC, CBD, or THC+CBD vs Placebo on Neuropathic Pain as measured by the Numeric Rating Scale of Pain
The mean change in the weekly average of daily Numeric Rating Scale (NRS) pain score (0-10 scale; 0=no pain, 10=worst possible pain) from baseline to week 6.
Measured: Baseline, Week 6
Secondary outcomes (11)
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in pain quality (allodynia) as measured by the Quantitative Sensory Testing.
Allodynia measured by Quantitative Sensory Testing (QST) (0-10 scale; 0=no pain, 10=worst possible pain)
Measured: Baseline, Week 2, Week 4, Week 6, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in disability and function as measured by the Neuropathic Pain Scale.
Neuropathic Pain Scale (NPS) total score; 7 different questions/sensations (for each individual item 0-10 scale; 0= not present/no pain, 10= most sensation). Individual scores analyzed separately for pain quality and mean score analyzed for overall neuropathic pain).
Measured: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in disability and function as measured by the Gait Speed Test
Distance walked (meters)/time (seconds) measured by Gait Speed Test (lower score = worse, higher score =better)
Measured: Baseline, Week 4, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in perceived improvement as measured by the Patient Global Impression of Change
Patient Global Impression of Change (PGIC) 1-7 point ordinal scale assessed (1 = worse, 7 = better)
Measured: Baseline, Week 2, Week 4, Week 6, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in perceived improvement as measured by the patient satisfaction visual analog scale.
Patient satisfaction with intervention on visual analog scale (VAS, 0-100, 0=no satisfaction, 100 = complete satisfaction).
Measured: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in quality of life measured by the Veterans RAND 12 Item Health Survey
Mental Component Score (MCS) and Physical Component Score (PCS) measured by Veterans RAND 12 Item Health Survey (VR-12). VR-12 is an algorithmic score with ranges from 0-100 (0 indicates worse health-related quality of life and 100 represents better health-related quality of life).
Measured: Baseline, Week 4, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in anxiety measured by the Generalized Anxiety Disorder-7.
Generalized anxiety symptomology is measured by Generalized Anxiety Disorder-7 (GAD-7) total score. (total score ranges from 0-21; Score 0-4 = minimal anxiety, Score 5-9 = mild anxiety, Score 10-14 = moderate anxiety, Score 15-21 = severe anxiety)
Measured: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in pain quality as measured by the Short Form McGill Pain Questionnaire (SF-MPQ-2).
Short Form McGill Pain Questionnaire (SF-MPQ-2) total score and four subscales (continuous pain, intermittent pain, predominantly neuropathic pain, affective). (0= no pain to 5= excruciating pain)
Measured: Baseline, Week 2, Week 4, Week 6, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in disability and function as measured by the Brief Pain Inventory-Diabetic Peripheral Neuropathy.
Brief Pain Inventory-Diabetic Peripheral Neuropathy (BPI-DPN) pain intensity score (first four items 0-10; 10= pain as bad as can imagine) (remaining items 0% (no relief)-100% (complete relief)) and pain interference score (0-10, 10= completely intense).
Measured: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in emotional functioning (severity of depression) as measured by the Patient Health Questionnaire-9.
Severity of depression is measured by Patient Health Questionnaire-9 (PHQ-9) total score (0-27; 0=none, 27=worst).
Measured: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in emotional functioning (PTSD symptoms) as measured by the PTSD Checklist-DSM-5 (PCL-5).
PTSD symptoms are assessed by PTSD Checklist-DSM-5 (PCL-5) total score symptom severity score (0-80; 0= not at all to 80= worst).
Measured: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Apr 2022
- Study start21 Jun 2023
- Primary completion29 Sep 2028 (estimated)
- Study completion31 May 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Neuropathic PainStudies of the same condition, open and under way.
- More trials run by VA Office of Research and DevelopmentThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Double-blind, randomized, placebo-controlled, parallel group Phase II study with randomization to one of the four treatment arms: 1) 10 mg mg THC , 2) 800 mg CBD , 3) 10.8 mg THC + 10 mg CBD , and 4) placebo. The 8-week treatment phase comprises a 2-week up-titration, 4 weeks maintenance on the target dose followed by 2 weeks down-titration, to minimize cannabis withdrawal syndrome. The two-weeks up titration phase is to minimize side effects and improve tolerability. Efficacy will be assessed by responses during the 4-week target dose phase.
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 320 participants (estimated)
Sponsor and investigators
- Lead sponsor
- VA Office of Research and Development
- Sponsor type
- US federal agency
- Responsible party
- Sponsor
- Investigators
- Deepak D'Souza, MD MBBS, Principal investigator, VA Connecticut Healthcare System West Haven Campus, West Haven, CTDonald McGeary, PhD, Principal investigator, South Texas Health Care System, San Antonio, TX
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05351801
- Sponsor's protocol ID
- NURP-002-20F
- Acronym
- CAN
- Status last verified
- Feb 2026
- First submitted
- 8 Apr 2022
- Last updated
- 27 Feb 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Proof of Concept Trial of Cannabis Derivatives in Neuropathic Pain
- ClinicalTrials.gov ID
- NCT05351801
- Acronym / sponsor ID
- CAN / NURP-002-20F
- Conditions
- Neuropathic Pain, Peripheral Neuropathic Pain
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 320 participants (estimated)
- Lead sponsor
- VA Office of Research and DevelopmentUS federal agency
- Study start
- 21 Jun 2023 (actual)
- Primary completion
- 29 Sep 2028 (estimated)
- Study completion
- 31 May 2029 (estimated)
- First posted
- 28 Apr 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Chronic neuropathic pain (CNP) is disabling. Research on frontline treatments for CNP, shows inconsistent outcomes and dissatisfaction among Veterans. Veterans and clinicians have shown significant interest in cannabis derivatives (THC, CBD) for neuropathic pain control, but there are no well-controlled trials guiding expectations for benefit and adverse outcomes associated with cannabis for CNP. Because Veterans are likely to present with pain and pain-related polymorbidity significantly differing from that of civilians, a well-structured clinical trial of cannabinoids for Veterans with CNP is vital.
Detailed description
Chronic pain is a significant burden to United States Veterans and is a particular concern for Veterans. One of the causes of pain is chronic neuropathic pain (CNP). Frontline treatment for CNP, show inconsistent outcomes and have significant side effects. The ongoing opioid crisis has led to significant interest in safe and effective alternatives for pain control, and there is a significant need for research on desirable options for pain control that are likely to improve treatment adherence and outcomes. Veterans groups and Veterans Affairs clinicians have expressed significant interest in cannabis and its principal constituents (delta-9-tetrahydrocannabinol, THC; cannabidiol, CBD) for pain management, but the extant research describing the potential risks and benefits of cannabis for pain is weak. This randomized trial was developed as a proof of concept study to determine if cannabis constituents (THC, CBD, and THC+CBD) are superior to placebo in reducing pain in Veterans with CNP. The study is to recruit a sample of 320 adult Veterans who meet diagnostic criteria for high-impact CNP, are on stable treatment(s) for CNP, are not current cannabis users and who do not meet diagnostic criteria for Cannabis Use Disorder. This randomized phase II, 4-arm clinical trial aims to determine if cannabis constituents (THC, CBD) or their combination (THC+CBD) are superior to placebo in reducing pain in Veterans with CNP. This trial will offer the first evidence describing the potential benefits and adverse effects of cannabinoids for CNP in Veterans.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 4
- Model description
- Double-blind, randomized, placebo-controlled, parallel group Phase II study with randomization to one of the four treatment arms: 1) 10 mg mg THC , 2) 800 mg CBD , 3) 10.8 mg THC + 10 mg CBD , and 4) placebo. The 8-week treatment phase comprises a 2-week up-titration, 4 weeks maintenance on the target dose followed by 2 weeks down-titration, to minimize cannabis withdrawal syndrome. The two-weeks up titration phase is to minimize side effects and improve tolerability. Efficacy will be assessed by responses during the 4-week target dose phase.
| Arm | Type | Receives |
|---|---|---|
| THC (Syndros) | Active comparator | Drug: THC (Syndros), Drug: PlaceboTarget dose of 10mg per day. |
| CBD (Epidolex) | Active comparator | Drug: CBD (Epidolex), Drug: PlaceboTarget dose of 800 mg per day. |
| THC + CBD (Nabiximols) | Active comparator | Drug: THC + CBD (Nabiximols), Drug: PlaceboTarget dose of 10.8 mg / 10 mg per day. |
| Placebo | Placebo comparator | Drug: PlaceboIdentical in appearance to the three active comparators. |
Who may qualify
- Ages
- 21 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Able to provide written consent
- Veterans 21 years and older at the date of screening
- Meet diagnostic criteria for neuropathic pain as defined by the Neuropathic Pain Special Interest Group of the International Association for the Study of Pain (NeuPSIG)
- Meet criteria for persistent, high-impact pain criteria.
- Presence of allodynia confirmed by one of the screening dynamic brush tests
Key exclusion criteria (14 listed)
- Actively engaged in or planning to enter a program of non-pharmacological invasive intervention for pain at the time of enrollment
- Peripheral neuropathy is not a primary source of neuropathic pain
- Hypersensitivity to THC, CBD, or THC/CBD
- Self-report of cannabis use during screening phase confirmed by positive urine toxicology for THC-COOH as measured and resulted at visit 5 before randomization
- Unwilling to refrain from using cannabis or cannabis-based products through the entire duration of the study
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| THC (Syndros)Participants will receive a target dose of 10mg per day of THC (Syndros). | Drug | THC (Syndros) |
| CBD (Epidolex)Participants will receive a target dose of 800 mg per day of CBD (Epidolex). | Drug | CBD (Epidolex) |
| THC + CBD (Nabiximols)Participants will receive a target dose of 10.8 mg / 10 mg per day of THC + CBD (Nabiximols). | Drug | THC + CBD (Nabiximols) |
| PlaceboPlacebo | Drug | CBD (Epidolex), Placebo, THC (Syndros), THC + CBD (Nabiximols) |
Primary outcome
To compare the short-term efficacy of THC, CBD, or THC+CBD vs Placebo on Neuropathic Pain as measured by the Numeric Rating Scale of Pain
Time frame: Baseline, Week 6
The mean change in the weekly average of daily Numeric Rating Scale (NRS) pain score (0-10 scale; 0=no pain, 10=worst possible pain) from baseline to week 6.
11 secondary outcomes
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in pain quality (allodynia) as measured by the Quantitative Sensory Testing.
Time frame: Baseline, Week 2, Week 4, Week 6, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in disability and function as measured by the Neuropathic Pain Scale.
Time frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in disability and function as measured by the Gait Speed Test
Time frame: Baseline, Week 4, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in perceived improvement as measured by the Patient Global Impression of Change
Time frame: Baseline, Week 2, Week 4, Week 6, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in perceived improvement as measured by the patient satisfaction visual analog scale.
Time frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in quality of life measured by the Veterans RAND 12 Item Health Survey
Time frame: Baseline, Week 4, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in anxiety measured by the Generalized Anxiety Disorder-7.
Time frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in pain quality as measured by the Short Form McGill Pain Questionnaire (SF-MPQ-2).
Time frame: Baseline, Week 2, Week 4, Week 6, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in mean changes in disability and function as measured by the Brief Pain Inventory-Diabetic Peripheral Neuropathy.
Time frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in emotional functioning (severity of depression) as measured by the Patient Health Questionnaire-9.
Time frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
To assess the efficacy of THC, CBD, or THC+CBD vs Placebo in emotional functioning (PTSD symptoms) as measured by the PTSD Checklist-DSM-5 (PCL-5).
Time frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 5, Week 6, Week 7, Week 8
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Feb 2026.
- Individual participant dataSharing planned: No
Related trials for Neuropathic Pain
RecruitingObservational study
Pain Phenotypes in Individuals With Multiple Sclerosis
Multiple Sclerosis, Chronic Pain
Enrolling by invitationPhase 4
Low Dose Naltrexone Therapy for Complex Regional Pain Syndrome
Complex Regional Pain Syndrome, Chronic Pain
RecruitingPhase 2
Effectiveness of Phenotype-based Pain Management Guidelines for Head and Neck Cancer Related Pain: a Pilot Study
Cancer Pain, Orofacial Pain
RecruitingPhase 2
A Master Protocol Study (LY900028) of Multiple Intervention-Specific-Appendices (ISAs) in Participants With Chronic Pain
Osteoarthritis, Knee, Diabetic Neuropathic Pain
RecruitingObservational study
Trigeminal Neuralgia Electrophysiology
Trigeminal Neuralgia
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Deepak D'Souza, MD MBBS principal investigator
VA Connecticut Healthcare System West Haven Campus, West Haven, CT
Donald McGeary, PhD principal investigator
South Texas Health Care System, San Antonio, TX
6 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing THC (Syndros), CBD (Epidolex) and THC + CBD (Nabiximols) in people with Neuropathic Pain and Peripheral Neuropathic Pain, run by VA Office of Research and Development at 6 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 14 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 27 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Courtney C DiCocco ((203) 932-5711, Courtney.DiCocco@va.gov), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To compare the short-term efficacy of THC, CBD, or THC+CBD vs Placebo on Neuropathic Pain as measured by the Numeric Rating Scale of Pain (time frame: Baseline, Week 6). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Feb 2026.