A Randomized, 4-sequence, 2-period, Double-blind, Placebo Controlled Study With a DSM-IV-TR Diagnosis of Cocaine Abuse

There will be a 28-day screening period with eligible subjects remaining resident in the
clinic from the evening before Day -1 up and until the morning of Day 9. On the morning of
Day 1, a 50 mg intravenous (IV) infusion of cocaine will be administered over 10 minutes to
all subjects. If none of the stopping criteria were met and no intervening safety concerns,
subjects will be randomized to one of the treatment sequences on Day 3. On dosing days, Day
3 and Day 6, subjects will have fasted at least 8 hours before dosing of cocaine and either
RBP-8000 200 mg, RBP-8000 100 mg or matching placebo.

Inclusion Criteria:

- Male and female volunteers aged 21-50 years, inclusive

- Body mass index (BMI)18-32 kg/m^2 and weight of at least 50 kg

- Not currently seeking treatment for substance abuse or substance dependence

- Subject is healthy, in the opinion of the Principal Investigator other than cocaine
abuse; as determined by the absence of clinically significant medical/psychiatric
history or findings, particularly cardiovascular or central nervous system (CNS)
disease, physical examination, normal renal function, ECG findings, vital signs, and
laboratory results at screening

- Males agree to refrain from sperm donations for the entire duration of the study, and
for at least 90 days after the last dose of study drug

- Has experience using cocaine by the smoked or IV route at least 6 times in past 12
months and a positive urine drug screen for cocaine prior to study intake (Day -2).
Has experience using cocaine by the smoked or IV route in the past 3 months and a
positive urine drug screen for cocaine during screening prior to study check-in at
the clinic

- Be able to verbalize understanding of the consent form, able to provide written
informed consent, and verbalize willingness to complete study procedures, prior to
the initiation of any protocol-specific procedures

- Meet DSM-IV-TR criteria for current cocaine abuse

- Be able to comply with protocol requirements, rules, and regulations of the study
site, and be likely to complete all the study procedures in the opinion of the
Principal Investigator

Exclusion Criteria:

- Current or past history of seizure disorder, including alcohol- and/or
stimulant-related seizure, febrile seizure, or significant family history of
idiopathic seizure disorder. Have any previous clinically significant reaction to
cocaine, including loss of consciousness or seizure

- Current alcohol dependence or current drug dependence according to DSM-IV-TR criteria
(excluding nicotine and caffeine)

- Clinically significant history of cardiac disease, including cardiovascular and
conduction abnormalities or ECG evidence of cardiac abnormalities

- QTcF greater than or equal to 450 for male subjects and 470 for female subjects as
measured through a 12-lead ECG

- History of liver disease or current elevation of aspartate aminotransferase (AST) or
alanine aminotransferase (ALT) exceeding 3x the upper limit of normal

- Be on probation or parole, and/or have current or pending legal charges with the
potential for incarceration that could interfere with the study scheduling

- Women with a positive pregnancy test at screening; or women who are pregnant or
lactating or who are seeking to become pregnant

- Women of childbearing potential (who are sexually active with a male) who fail to use
medically acceptable contraception methods (e.g., an oral or injectable
contraceptive, an approved hormonal implant or topical patch, an intrauterine device,
a double barrier method, or barrier plus spermicide). A woman of childbearing
potential is defined as any female who is less than 2 years post-menopausal or has
not undergone a hysterectomy or surgical sterilization, e.g., bilateral tubal
ligation, bilateral ovariectomy (oophorectomy). Females that are post-menopausal will
be confirmed as such by the follicle stimulating hormone (FSH) test at initial
screening

- Males who do not agree to use barrier contraception and spermicide when engaging in
sexual activity with a female of child-bearing potential while on study medication,
and for at least 28 days after the last dose of study medication

- History of clinically significant severe allergic or anaphylactic reactions