Clinical Trial of High Dose Lisdexamfetamine and Contingency Management in MA Users

Inclusion Criteria:

• Participant must meet all the following criteria:

1. Between 18 and 55 years of age;

2. Diagnosed with a moderate to severe methamphetamine (MA) use disorder asdefined by the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, 5th edition) criteria;

3. Active MA use at screening measured via self-reported MA use ≥14 days in thepast 28 days AND verified by urine drug metabolite testing;

4. Interested in reducing/stopping MA use;

5. If female:

6. Be of non-childbearing potential, defined as (i) postmenopausal (12 monthsof spontaneous amenorrhea and ≥ 45 years of age); or (ii) documentedsurgically sterilized (i.e., tubal ligation, hysterectomy, or bilateraloophorectomy); or

7. Be of childbearing potential, have a negative pregnancy test at screening,and agree to use an acceptable method of birth control throughout thestudy;

8. Willing to be randomized to one of the 4 study arms and followed for theduration of the trial;

9. Able to provide informed consent;

10. Willing to comply with study procedures;

11. Able to communicate in English or French.

Exclusion Criteria:

1. Symptomatic or advanced cardiovascular disease (e.g., advancedarteriosclerosis), moderate hypertension; current hyperthyroidism confirmed viablood test; known hypersensitivity or idiosyncrasy to the sympathomimeticamines or glaucoma or any disabling, severe, OR unstable medical conditionthat, in the opinion of the study physician, precludes safe participation orthe ability to provide fully informed consent; 2. Any severe or unstableco-morbid substance use disorder that, in the opinion of the study physician,precludes safe participation in the study; 3. Participants with Opioid UseDisorder (OUD) who have been on Opioid Agonist Therapy (OAT) for < 12 weeks,and not yet at stabilization dose, or at stabilization dose < 4 weeks; 4.Current or history of any serious psychiatric disorder (e.g., bipolar disorder,pre-existing psychosis, schizophrenia) that, in the opinion of the studyphysician, precludes safe participation in the study; 5. History of a severeadverse event, hypersensitivity or known allergic reaction to LDX or otheramphetamine drugs OR hypersensitivity to the sympathomimetic amines; 6.Pregnant, nursing, or planning to become pregnant during the study period; 7.Planned extended absence during study period (e.g., pending legal action,surgery, incarceration, inpatient residential program) in the opinion of thestudy physician that might prevent completion of the study; 8. Use of aninvestigational drug for stimulant use disorder during the 30 days prior toscreening, confirmed via self-report OR pharmacy records; 9. Currentlyreceiving contingency management for the treatment of stimulant use disorder inthe 4 weeks prior to screening, confirmed via self-report OR site records; 10.Use of prescribed amphetamine-type medication OR medication for the treatmentof stimulant use disorder (e.g., methylphenidate, modafinil, bupropion) in the 4 weeks prior to screening; 11. Current or anticipated need for treatment withany medication that may interact with LDX (e.g., proton pump inhibitors,monoamine oxidase inhibitors [MAOIs]) used currently or within the past 14 daysAND that would preclude study participant at the discretion of the studyphysician