Dextroamphetamine as Adjunct in Cocaine/Opiate Dependent Patients - 3

This 27-week double-blind, placebo controlled treatment is designed to evaluate
dextroamphetamine sulfate (sustained release) as an adjunct in concurrent cocaine and opiate
dependent patients. All subjects will receive methadone. For the treatment of cocaine
dependence, subjects will receive one of 2 doses of dextroamphetamine (15 or 30mg) or
placebo. After 4 weeks of treatment the dose level of dextroamphetamine is doubled (30 or
60mg). This dose is maintained for 20 weeks; during which subjects attend twice weekly
visits to the clinic and receive weekly cognitive behavioral therapy. Follow up evaluations
will be conducted out to 3 months post treatment. Subjects will be assisted in transferring
to Houston area methadone clinics to maintain treatment for opiate dependence following
treatment completion.

Inclusion Criteria- Subject must:

- Exhibit cocaine and opiate dependence through a DSM-IV diagnosis as determined by
SCID.

- Be between 18 and 45 years old

- Women must agree to use contraception

- Have an EKG that has been confirmed by a cardiologist

- Give a cocaine positive urine during screening - Present with evidence of opiate
withdrawal

Exclusion Criteria- Subject must not:

• Have a serious medical illness including, but not limited to the following: Hypertension
Significant heart disease Clinically significant cardiovascular abnormality Angina
Hepatic, renal, or gastrointestinal disorders that could result in an altered metabolism
or excretion of study agent

- Have any Axis I disorder that is not related to drug use

- Have current dependence on any psychoactive disorder other than nicotine

- Be on probation or parole for reasons other than those related to drug charges (ASI)

- Be pregnant or lactating

- Have been in any outside treatment in 3 months