Evaluation of Medical Cannabis and Prescription Opioid Taper Support for Reduction of Pain and Opioid Dose in Patients With Chronic Non-Cancer Pain

This study will use a randomized controlled design to test whether medical marijuana use by adults on high-dose chronic opioid therapy (COT) for chronic non-cancer pain is associated with reduced opioid dose and improved pain intensity and interference when added to a 24-week behavioral intervention (POTS).

This trial is a randomized, six-month study of medical marijuana (MM) on opioid use that will: (1) evaluate whether adults with chronic, non-cancer pain on COT assigned to MM+POTS, compared with those assigned to WL+POTS, have greater reduction in opioid dose and/or pain intensity and interference, (2) assess whether participants assigned to MM+POTS, compared with those assigned to WL+POTS, have improved quality of life, depression, and anxiety; and reduced self-reported opioid dose, (3) evaluate whether those assigned to MM+POTS develop symptoms of CUD and have a reduced number of OUD symptoms over the 24-week intervention, as well as at the 12-month time point.

Participants will be randomly assigned to either an active MM arm (n = 60), or to a waitlist control arm (WLC) (n = 60). Participants will be assessed at baseline, every 4 weeks for 6 months, and at a 12-month follow-up for opioid use, development of CUD, development or resolution of OUD, and neurocognitive performance. Urine collected will be assessed with quantitative assays.

Eligibility Criteria:
Inclusion Criteria:

1. Men and women aged 18-75, inclusive.
2. Endorsing \> 6 months of chronic, non-cancer pain.
3. On stable prescription opioid doses of 25 MME or greater for \>90 days, verified by the Prescription Monitoring Program.
4. Either no prior use or current light cannabis use (weekly or less in the past 12 months).
5. Plans to use medical cannabis for pain to control pain and/or reduce opioid dose.
6. Competent and willing to provide written informed consent in English.
7. Potential participants of childbearing potential must not be pregnant at enrollment. They will be asked to self-report pregnancy status and the start date of their most recent menstrual period and agree to use effective contraception: abstinence; hormonal contraception; intra-uterine device, sterilization; or double barrier contraception, during the study.

Exclusion Criteria:

1. Current cannabis use (including inhaled or ingested CBD products) of greater than weekly on average in the past 12 months, assessed via self-report (no more than 10 times in the past 90 days).
2. Current cannabis use disorder; current moderate to severe substance use disorder for any substance by structured interview, EXCEPT nicotine and opioids (OUD).
3. Current uncontrolled major medical illness, such as cancer, symptomatic hypothyroidism/hyperthyroidism or severe respiratory compromise.
4. Use of non-prescribed opioids, by self-report.
5. Dose change or initiation of medications with significant analgesic effects (e.g., tricyclic antidepressants, SSRIs, gabapentin, NSAIDs) in the past 4 weeks.
6. Concomitant medications will be discussed at each study visit, and any medications that may interact with cannabinoids (e.g., warfarin) will be discussed with a study clinician prior to enrollment or continued participation.
7. Actively suicidal and/or suicide attempt or psychiatric hospitalization in past year, or current suicidal ideation with specific plan or intent.
8. History of intellectual disability (e.g., Down's syndrome) or other severe developmental disorder or IQ \< 70.
9. Current diagnosis of delirium, dementia, amnestic, or other cognitive disorder; current diagnosis of bipolar II disorder; lifetime diagnosis of bipolar I disorder, schizophrenia spectrum, or other psychotic disorder.
10. Surgery within the past month or planned during the next 6 months.
11. Pregnant or trying to get pregnant or breastfeeding.
12. In the opinion of the investigator or study physicians, not able to complete study procedures or safely participate in this study.