Marijuana-based Drug for Anxiety in Autistic Adults

Inclusion Criteria: 1. Male or female age 18 to 45 years old with an autism diagnosis. 2. Participant is ≥ 100 lbs. 3. Participant or a legally authorized representative provides informed consent/assent for participation in the trial. 4. Participant/caregiver is willing and able to comply with all study procedures. 5. Participant meets ADOS-2 criteria for Autism or Autism Spectrum 6. Participant meets DSM-5 criteria for ASD. 7. Participant has a minimum CGI-S (Anxiety) score ≥ 5 based on anxiety related social functional impairment. 8. Participant has a FSIQ ≥ 65 at screening measured with the WASI- II, or within 1 year of screening with a comparable assessment. 9. Participant must have a negative pregnancy test (urine and serum) at Screening, and a negative urine test at Baseline, Active Phase Visits, and EoS visits, see Table 1. Schedule of Activities. 10. Sexually active participants agree to use two methods of effective birth control, as described in Appendix B: Contraceptive and Barrier Guidance during the study intervention period and for at least 14 days after the Study Termination visit. 11. Participant must be stable on any pre-study medications and/or psychotherapy for 6-weeks prior to study enrollment, agree to inform prescribing clinician(s) about participation in the study, and agree to maintain medication or psychotherapy treatment regimen during the study. 12. Participant must be able to ingest MB-IMP (or placebo) and be willing to commit to medication dosing and completing the dosing diary. 13. Participant/caregiver agrees to keep all study medication provided by site staff securely stored at home and not to share/distribute study medication to any other individual. 14. Participant agrees not to participate in any other interventional clinical trials during the study period. 15. Participant agrees to inform the investigators within 48- hours of any side-effects, medical conditions, and procedures. 16. Participant agrees to abstain from alcohol use during the study. Exclusion Criteria: 1. Participant weighs \< 100 lbs. 2. Participant is sexually active and does not practice two effective forms of birth control. 3. Participant is pregnant, lactating, or planning pregnancy during the study period or within 12 weeks thereafter. 4. Participant has a current or historical psychotic features/disorder assessed via the Mini-International Neuropsychiatric Interview (MINI). 5. Participant has a current or historical DSM-5 diagnosis of dissociative identity disorder, positive family history (first-degree relative) of psychotic disorder or bipolar disorder type 1. 6. At high risk of suicide or suicide attempts. 1. Individuals presenting current serious suicide risk, as determined through psychiatric interview, responses to the Columbia Suicide Severity Rating Scale (C-SSRS), and/or clinical judgment of the investigator. 2. History of suicide attempts within 12 months prior to study enrollment. 7. Participant has a current substance use disorder within the 12 months prior to enrollment as determined by the MINI Kid56. 8. Participant's urine drug screen is positive for opiates, methamphetamine, cocaine, THC, and amphetamines (unless prescribed). Participants with positive THC urine analysis tests are excluded from the study but will be allowed to rescreen (maximum twice) after a 1-month cessation of cannabis use. 9. Participant has a history of arrhythmia, other than occasional premature atrial contractions (PACs) and premature ventricular contractions (PVCs) without ischemic heart disease, within 12 months of screening. 10. Participant with a history of atrial fibrillation, atrial tachycardia, atrial flutter or paroxysmal supraventricular tachycardia, or any other arrhythmia associated with a bypass tract, may be enrolled only if they have been successfully treated with ablation and have not had a recurrent arrhythmia for at least one year off all antiarrhythmic drugs or are under adequate and stable pharmacologic treatment for atrial fibrillation for at least a year, as confirmed by a cardiologist. 11. Participant has a current diagnosis or evidence of significant or uncontrolled hematological, endocrine, cerebrovascular, cardiovascular, coronary, pulmonary, gastrointestinal, renal, immunocompromising, or neurological disease according to PI's discretion. 12. Evidence of existing hepatocellular injury defined as alanine transaminase (ALT) and aspertate aminotranferase (AST) elevations of greater than 3 times upper limit normal (ULN) and bilirubin elevation of greater than 2 times ULN. 13. The PI or medical monitor deems the participant inappropriate for the study for any reason. 14. Any known allergies/sensitivities to cannabis (in the opinion of the investigator). 15. Not able to attend required face-to-face visits or those who plan to move out of the area within the treatment period.