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Despite years of active research, there are still no approved medications for the treatment of cocaine dependence. Modafinil is a glutamate-enhancing agent that blunts cocaine euphoria under controlled conditions, and the current study assessed whether modafinil would improve clinical outcome in cocaine-dependent patients receiving standardized psychosocial treatment. This was a randomized, double-blind, placebo-controlled trial conducted at a university outpatient center (from 2002 to 2003) on a consecutive sample of 62 (predominantly African American) cocaine-dependent patients (aged 25-63) free of significant medical and psychiatric conditions. After screening, eligible patients were randomized to a single morning dose of modafinil (400 mg), or matching placebo tablets, for 8 weeks while receiving manual-guided, twice-weekly cognitive behavioral therapy. The primary efficacy measure was cocaine abstinence based on urine benzoylecgonine levels. Secondary measures were craving, cocaine withdrawal, retention, and adverse events. Modafinil-treated patients provided significantly more BE-negative urine samples (p=0.03) over the 8-week trial when compared to placebos, and were more likely to achieve a protracted period (> or =3 weeks) of cocaine abstinence (p=0.05). There were no serious adverse events, and none of the patients failed to complete the study as a result of adverse events. This study provides preliminary evidence, which should be confirmed by a larger study, that modafinil improves clinical outcome when combined with psychosocial treatment for cocaine dependence.
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A Double-Blind, Placebo-Controlled Trial of Modafinil
for Cocaine Dependence
Charles A Dackis*
, Kyle M Kampman
, Kevin G Lynch
, Helen M Pettinati
and Charles P O’Brien
University of Pennsylvania School of Medicine, Philadelphia, USA;
Department of Veterans Affairs Medical Center, Philadelphia, USA
Despite years of active research, there are still no approved medications for the treatment of cocaine dependence. Modafinil is a
glutamate-enhancing agent that blunts cocaine euphoria under controlled conditions, and the current study assessed whether modafinil
would improve clinical outcome in cocaine-dependent patients receiving standardized psychosocial treatment. This was a randomized,
double-blind, placebo-controlled trial conducted at a university outpatient center (from 2002 to 2003) on a consecutive sample of 62
(predominantly African American) cocaine-dependent patients (aged 25–63) free of significant medical and psychiatric conditions. After
screening, eligible patients were randomized to a single morning dose of modafinil (400 mg), or matching placebo tablets, for 8 weeks
while receiving manual-guided, twice-weekly cognitive behavioral therapy. The primary efficacy measure was cocaine abstinence based
on urine benzoylecgonine levels. Secondary measures were craving, cocaine withdrawal, retention, and adverse events. Modafinil-treated
patients provided significantly more BE-negative urine samples (p¼0.03) over the 8-week trial when compared to placebos, and were
more likely to achieve a protracted period (X3 weeks) of cocaine abstinence (p¼0.05). There were no serious adverse events, and
none of the patients failed to complete the study as a result of adverse events. This study provides preliminary evidence, which should be
confirmed by a larger study, that modafinil improves clinical outcome when combined with psychosocial treatment for cocaine
Neuropsychopharmacology (2005) 30, 205–211, advance online publication, 3 November 2004; doi:10.1038/sj.npp.1300600
Keywords: modafinil; cocaine; glutamate; pharmacotherapy; abstinence; addiction
Cocaine dependence is a major public health problem that
is characterized by recidivism and a host of medical and
psychosocial complications. An effective pharmacotherapy
has long been sought to improve treatment outcomes,
particularly since this disorder has a significant neurobio-
logical basis (Volkow and Fowler, 2000; Dackis and O’Brien,
2001; Ahmed et al, 2002). Although proven pharmacothera-
pies are available for alcohol and heroin dependence
(O’Brien, 2001), none exist for cocaine dependence despite
two decades of clinical trials primarily involving antide-
pressants, anticonvulsants, and dopaminergic medications.
Testing glutamate-enhancing agents is a new and promising
strategy based on recent findings that cocaine dysregulates
reward-related glutamate pathways (Thomas et al, 2001;
Dackis and O’Brien, 2003; Kalivas et al, 2003).
Modafinil is a wake-promoting agent that is approved for
narcolepsy. Its glutamate-enhancing action (Ferraro et al,
1998, 1999) might be clinically advantageous in cocaine
dependence because the repeated administration of cocaine
depletes extracellular glutamate levels (Keys et al, 1998; Bell
et al, 2000; Hotsenpiller et al, 2001; Kalivas et al, 2003), and
reduces glutamatergic synaptic strength in the nucleus
accumbens (Thomas et al, 2001). Furthermore, it has
recently been demonstrated that normalizing extracellular
glutamate levels with N-acetylcysteine abolishes cocaine-
induced reinstatement, an animal model of relapse (Baker
et al, 2003). Modafinil has also been proposed as a cocaine
detoxification agent (Dackis et al, 2003). Cocaine with-
drawal symptoms (see Table 1) predict poor outcome
(Kampman et al, 2001), and modafinil would be expected to
reverse these symptoms as it is activating (Dackis et al,
2003). In addition, it has recently been reported that
patients with baseline cocaine withdrawal (Sofuoglu et al,
2003), and abstinence-related depression and irritability
(Newton et al, 2003), report enhanced euphoria after
cocaine administration under controlled conditions, sug-
gesting that the reversal of cocaine withdrawal might be
clinically advantageous. Modafinil is a reasonable medica-
tion for cocaine-dependent individuals because it has low
abuse potential (Jasinski, 2000; Jasinski and Kovacevic-
Online publication: 24 September 2004 at
Received 8 June 2004; revised 23 September 2004; accepted 24
September 2004
*Correspondence: CA Dackis, University of Pennsylvania Treatment
Research Center, 3900 Chestnut Street, Philadelphia, PA 19104, USA,
Tel: þ1 215 662 8752, Fax: þ1 215 243 4665,
Neuropsychopharmacology (2005) 30, 205211
2005 Nature Publishing Group All rights reserved 0893-133X/05
Ristanovic, 2000; Rush et al, 2002a, b), neurochemical
effects that differ markedly from those of psychostimulants
(Lin et al, 1996; Ferraro et al, 1997), and good tolerability
(Becker et al, 2004).
Given these considerations, we began to investigate
modafinil in cocaine-dependent patients some time ago by
conducting a drug interaction study. This study not only
found that modafinil was safely co-administered with
intravenous cocaine, but also reported that modafinil
significantly blunted cocaine-induced euphoria under con-
trolled conditions (Dackis et al, 2003). The consistency of
this interesting property was strengthened by another
controlled study reporting attenuated cocaine euphoria in
modafinil-treated patients (Malcolm et al, 2002). We
subsequently conducted an open-label modafinil trial and
reported high levels of cocaine abstinence in patients
experiencing severe cocaine withdrawal at baseline (Dackis
and O’Brien, 2003). The current study is a randomized,
double-blind, placebo-controlled, 8-week trial of modafinil
in 62 cocaine-dependent outpatients.
Study Participants
We randomized 62 treatment-seeking patients (44 male, 18
female; mean age 44.5, SD 8.7; age range 25–63) from the
greater metropolitan Philadelphia area. Patients gave
written informed consent to participate in this trial, which
was approved by the University of Pennsylvania Human
Investigations Committee, and informed consent compre-
hension was assessed with a quiz that was re-administered
until completely correct. Patients were required to meet
Diagnostic and Statistical Manual of Mental Disorders
(DSM IV) criteria for cocaine dependence, and to have
used at least $200 worth of cocaine in the past 30 days.
Individuals were excluded if they were dependent on any
substance other than cocaine or nicotine, had serious active
medical illness (including uncontrolled hypertension, sig-
nificant cardiac, renal, or hepatic disease, or life-threatening
or progressive illness), psychiatric illnesses (history of
bipolar disorder, active psychosis, current major depres-
sion), required psychotropics or medications that might
interact with modafinil, or had significantly abnormal
baseline laboratory tests. Pregnant women were excluded
and, since modafinil induces the metabolism of steroidal
contraceptives, women of childbearing potential were
required to use other acceptable birth control methods.
Study Design
This was a randomized, double-blind, placebo-controlled 8-
week trial of modafinil for cocaine dependence. Enrollment
began in September 2002, ended in October 2003, and the
pilot study was completed in December 2003 to determine
whether a larger study was justified.The 2-week screening
period (3–4 visits) included a comprehensive physical
examination and history, blood counts (red and white cells,
platelets, hemoglobin, hematocrit), blood chemistries (elec-
trolytes, blood urea nitrogen, creatinine, total protein), liver
function tests (bilirubin, alkaline phosphatase, aspartate
aminotransferase, alanine amino transferase), urinalysis,
urine pregnancy test for women, and a 12-lead ECG. This
entire medical evaluation was repeated 4 and 9 weeks after
randomization. The diagnosis of current cocaine depen-
dence was confirmed with a Structured Clinical Interview
for DSM IV (SCID) (First et al, 1996), and other psychiatric
disorders were ruled out with the mini-international inter-
view (Sheenan et al, 1997). After screening, 62 eligible
patients were randomized (with a computer generated code)
to receive modafinil 400 mg/day (n¼30) or matching
placebo (n¼32) for 8 weeks. The research pharmacist
generated the allocation sequence, assigned participants to
their groups, and was the only person aware of the
medication assignment code that was kept in a sealed
envelope for emergency access. None of the research
personnel, who enrolled, treated, and assessed the patients,
were aware of the patient assignments until the study was
concluded. The study physician dispensed modafinil or
matched placebo pills (supplied by Cephalon, Inc.) to
patients in weekly blister packs that contained a 9-day
supply in case of a missed visit. Treatment was initiated
with a single morning dose of 4 pills/day (each containing
100 mg of modafinil or placebo), and discontinued without
taper after 8 weeks. The study physician had the option to
reduce the dosage in one-pill increments, to a minimum of 2
pills/day, if tolerability problems emerged.
The entire study was conducted at the University of
Pennsylvania Treatment Research Center, and included
thrice-weekly research technician assessments and weekly
physician assessments for adverse events, global improve-
ment, and concomitant medications. Patients were asked to
attend the clinic three times per week, and provide urine
samples during each visit. Two of these sessions included
CBT counseling, and at least one session per week included
an assessment by the study physician, who dispensed a
blister pack (9-day supply of study medications that they
took without staff observation) that was to be returned the
following week for adherence assessment. Patients were
paid $5 for each blister pack returned. Individual, manual-
guided CBT (Kadden et al, 1992) (adapted for substance
abuse) was provided twice weekly for 8 weeks, and CBT
sessions were audiotaped and reviewed for clinician manual
adherence by the supervising therapist. A follow-up end of
medication assessment was scheduled 1 week after the study
medications were discontinued.
Table 1 Clinical Effects of Modafinil are Largely Opposite to
Cocaine Withdrawal Symptoms
Cocaine withdrawal Modafinil effects
Hypersomnia Increased wakefulness
Depression Improved mood
Fatigue Increased energy
Poor concentration Improved attention and vigilance
Psychomotor retardation Locomotion (in animals)
Increased appetite Reduced feeding (in animals)
Enhanced cocaine euphoria Blunted cocaine euphoria
A double-blind, placebo-controlled trial of modafinil
CA Dackis et al
Outcome Measures, Schedule of Assessments, and
Sample Size
The primary efficacy measure for this trial was cocaine
abstinence based on thrice-weekly qualitative urinary
benzoylecgonine (BE) levels, and we hypothesized that
modafinil-treated patients would supply more BE-negative
urine samples than placebo-controlled patients over the 8-
week trial. Urine temperatures were measured at the time of
collection and acceptable samples (temperatures between
and 99
Fahrenheit) were analyzed with a fluorescent
polarization assay. Urine samples containing BE at con-
centrations X300 ng/ml were considered to be positive for
cocaine. Secondary efficacy measures included the weekly
physician-rated Clinical Global ImpressionFObjective
Scale (CGI-O), (Guy, 1976) self-reported cocaine use on
the Timeline Follow-Back Interview (TLFB) (Sobell and
Sobell, 1992) and Clinical Global Impression ScaleFSub-
jective (CGI-S) (Guy, 1976), and cocaine withdrawal/craving
measured by the Cocaine Selective Severity Assessment
(CSSA) (Kampman et al, 1998), Brief Substance Craving
Scale (BSCS) (Somoza et al, 1995), and Cocaine Craving
Questionnaire (CCQ) (Tiffany et al, 1993). In addition,
baseline demographics and clinical characteristics were
assessed with the Addiction Severity Index (ASI) (McLellan
et al, 1992), Hamilton Anxiety Scale (Ham A) (Hamilton,
1969), and Hamilton Depression Scale (Ham D) (Hamilton,
1967), Beck Depression Inventory (BDI) (Beck et al, 1974),
and the Symptom Checklist 90 Revised (SCL90) (Derogatis,
1977). Safety data were collected weekly, and included vital
signs (blood pressure, pulse, temperature), body weight,
and adverse events documented by the study physician on a
standardized form.
Statistical Analysis
The analysis was by intention-to-treat. The patients were
compared on a variety of baseline characteristics, using w
tests for categorical characteristics, and t-tests for contin-
uous characteristics, to assess how well the randomization
had balanced patient characteristics across the two (mod-
erately sized) treatment groups. The primary analyses did
not include additional covariates, but characteristics that
showed significant imbalance across the groups were
considered for inclusion as covariates in supplementary
analyses, together with characteristics known to be of
importance such as cocaine positive urine at baseline.
The repeated binary outcomes obtained from the
quantitative BE assays were analyzed using generalized
estimating equation (GEE) models (Diggle et al, 2002). In
these analyses, missing urine screens were imputed as
positive, which is a standard practice in clinical trials for
which cocaine abstinence is a primary outcome (Shoptaw
et al, 2002), although it does create a bias against treatment
dropouts. Other repeated outcomes (CGI-O, CGI-S, TLFB,
CSSA, BSCS, CCQ) were also analyzed using GEE models for
continuous or count responses. In all the repeated measures
analyses, the models included terms for treatment group
(placebo versus modafinil), together with linear and
quadratic time effects, and some group by time interactions.
Quadratic time effects were included in the models to allow
for the possibility that rates of cocaine use might decrease
(or increase) early in treatment, and remain at a lower (or
higher) level through the rest of the trial. Group by
quadratic time interactions allow these patterns to be
different for the different groups. In fitting these models to
the data, terms were included in the GEE models if they
were significant at the 5% level, and lower order effects
contained in a significant interaction effect were also
included. Model-based standard errors (Wald statistics)
were used to assess significance.
Baseline Measures
There were no significant (5% level) differences between the
modafinil and placebo groups on a battery of measures
drawn from the baseline ASI, TLFB, Ham A, Ham D, BDI,
SCL-90, and CSSA. A selection of important baseline
demographic, clinical, and psychosocial characteristics of
enrolled patients are listed in Table 2. As race, mean weekly
cocaine cost, mean days of weekly use, and years of lifetime
cocaine use were significant at the 10% level, they were
included as covariates in supplementary GEE analyses.
Pill Compliance
There were no significant differences between the modafinil
and placebo group on pill compliance or pill overuse. A
total of 41 patients (21 placebo, 20 modafinil) had at least 1
week where they did not return all of the expected unused
Table 2 Baseline Characteristics as Percentages or Means
(Standard Deviations) with p-Values Based on w
Tests for
Categorical Variables, or t-Tests for Continuous Characteristics
(n¼32) p-value
Age 46 (8.4) 43 (8.4) 0.28
% Males 67% 75% 0.47
% Married 23% 31% 0.49
Race (% African American) 90% 72% 0.07
Total years of education 12 (2.1) 13 (1.9) 0.27
Days in last 30 employed 11 (9.9) 15 (9.9) 0.11
% crack (smoking) use 87% 88% 0.92
% BE-positive baseline urines 63% 78% 0.20
CSSA scores at baseline 16 (12.1) 21 (13.2) 0.15
Days of cocaine use/week 2.0 (1.8) 2.9 (2.1) 0.07
Weekly cocaine cost 115 (113.8) 180 (203.3) 0.10
Years of cocaine use 14 (7.2) 11 (7.0) 0.10
Hamilton Anxiety Scale 7.4 (5.4) 8.7 (5.9) 0.36
Hamilton Depression Scale 12 (8.9) 14 (9.9) 0.31
Beck Depression Inventory 9.9 (7.5) 12.6 (9.7) 0.26
SCL-90 total score 30 (30.1) 53 (63.1) 0.30
Log-transformation performed prior to comparison of means.
A double-blind, placebo-controlled trial of modafinil
CA Dackis et al
pills in their blister packs (9-day supply given weekly). A w
test showed no difference in the group proportions with at
least one such week (w
(1) ¼0.01, p¼0.93). In each group,
the median number of weeks in which unprescribed
modafinil pills were retained 2 (third quartile of 3), and a
Mann–Whitney test of the number of weeks of unprescribed
pill retention among these patients showed no differences
between the two groups (Z¼0.14, p¼0.99). Across weeks
in which an excess of pills were used, the total numbers of
excess pills were also very similar: the mean 8-week-total
overused was 11.82 (SD ¼8.25) in the placebo patients, and
12.80 (8.52) in the modafinil patients (Mann–Whitney Z-
score ¼0.33, p¼0.77). When queried, patients typically
stated they could not recall, or were reluctant to disclose,
why they did not return the extra blister packaged pills.
Three modafinil-treated and four placebo-treated patients
retained more than 16 of the extra 64 pills supplied over 8
Treatment Retention
In the modafinil group, 19/30 (63.3%) of patients were still
present at the end of the eight weeks, compared to 21/32
(65.6%) in the placebo group. Also, for each group, the
median time to drop out was 24 visits. When defined as
failing to complete the first 2 weeks of treatment, there were
two dropouts in the modafinil group, and three in the
placebo group. A log-rank test showed no significant
difference in the distribution of time to drop out (w
(1) ¼0.79, p¼0.37). There was no significant difference
with regard to CBT attendance for the modafinil (50.0%)
compared to the placebo (54.6%) groups (t(60) ¼0.64,
Cocaine Abstinence
The trial was designed to obtain 24 urines from each patient
during medication treatment. The percent obtained of
expected urines for the modafinil group was 74.5%, and
for the placebo group was 63.0%: a t-test showed that the
average number of urines provided was not significantly
different across the two groups (t(60) ¼1.58, p¼0.12).
Figure 1 shows the within-group percentages of BE-negative
urines provided across the study. The mean proportion of
BE-free urines supplied (calculated for each patient as a
percentage of the 24 requested) was 42.3% for the modafinil
group, and 24.0% for the placebo group. A full GEE model
of the log-odds of a clean urine vs a missing or dirty urine
screen showed significant group by quadratic time
(Z¼2.25, p¼0.02) and group by linear time (Z¼2.49,
p¼0.01) effects. Examination of predicted probabilities of
BE-negative urine (‘abstinent visit’) suggested that the
groups had similar initial probabilities of a BE-negative
urine (0.29 for modafinil, 0.25 for placebo), that these
probabilities decreased steadily in the placebo group (0.23
at week 5 and 0.18 at week 8), and initially increased and
later decreased in the modafinil group (0.46 at week 5 and
0.32 at week 8). (Note: If significance was assessed using the
more conservative (Stokes et al, 2000) empirical standard
errors, then the group by quadratic effect was not
significant (p¼0.09), and dropping further nonsignificant
terms from the model yielded a final model with a
significant main effect for cocaine abstinence in the
modafinil group (odds ratio ¼2.41, 95% CI ¼(1.09, 5.31),
p¼0.03), compared to placebos, together with a significant
quadratic time effect.) Analyses adjusting for race, and for
baseline measures of mean weekly cocaine cost, mean days
of weekly use, and years of lifetime cocaine use, yielded
virtually identical estimates to those given by unadjusted
The baseline level of cocaine use has been reported to be
an important predictor of treatment outcome (Kampman
et al, 2001). In this study, there was a trend towards a higher
proportion of BE-positive urines at baseline in the placebo
group compared to the modafinil group. A complex model
was formulated that included terms representing baseline
urine BE status and its interactions with treatment group
and time. There was a significant group by baseline status
by quadratic time effect (p¼0.01), indicating significantly
different quadratic trends across the four groups (baseline
BE status by treatment condition). Table 3 shows the
estimated probabilities of an abstinent visit at the begin-
ning, middle, and end of the 8 weeks, for each of the four
As expected, based on previous work, the dominant effect
is that people with a BE-negative baseline status are more
likely to attain abstinent visits during the study. Within
each level of baseline status, the modafinil effect is similar to
that observed in the analyses described above: the groups
are similar at the beginning, the modafinil group appears to
improve more than the placebo group through the first 5
weeks, and the groups are similar at the end of the 8 weeks.
123 45 678
Study Week
Figure 1 Weekly cocaine abstinence in modafinil and placebo groups,
defined as the percentage of urine samples that were (1) submitted
(requiring attendance), and (2) found to be BE-negative. Missing urines are
therefore imputed as positive.
Table 3 Estimated Probabilities of an Abstinent Visit at the
Beginning, Middle, and End of the 8-Week Trial for the Placebo and
Modafinil Groups, According to Baseline BE Status
Tx group; baseline BE status Week 1 Week 5 Week 8
Placebo; BE-negative 0.68 0.46 0.56
Modafinil; BE-negative 0.64 0.61 0.45
Placebo; BE-positive 0.13 0.19 0.14
Modafinil; BE-positive 0.11 0.30 0.10
A double-blind, placebo-controlled trial of modafinil
CA Dackis et al
In addition to this effect, a greater percent of the modafinil
(33%) than placebo (13%) were able to attain prolonged
abstinence, as defined by the achievement of 3 consecutive
weeks of BE-negative urines (none missing) during any time
period (w
¼3.84, df ¼1, p¼0.05).
Patient-Reported Use (TLFB, CGO-S)
There were no significant modafinil effects on self-reported
(TLFB) rates of cocaine use (GEE model Z-score ¼0.35,
p¼0.73), or on dollars spent on cocaine (GEE model
Z-score ¼1.08, p¼0.28). CGI-S showed no differences
between modafinil and placebo groups in reported cocaine
severity (GEE model Z-score ¼0.37, p¼0.72) or func-
tional impairment.
Physician-Rated Assessments
The CGI-O summary scales were rated weekly by the study
physician. The modafinil group showed consistently lower
overall severity scores, and consistently greater improve-
ment scores, although these differences did not reach
significance: for the Global Severity of Cocaine Dependence
Scale (GEE model Z-score ¼1.47, p¼0.14); for the Global
Improvement of Cocaine Dependence of the CGI-O (GEE
model Z-score ¼1.88, p¼0.06).
Cocaine Craving and Withdrawal (CSSA, BCSC, CCQ)
There were no treatment group differences in the total CSSA
scores (mixed effects model F(1, 57) ¼0.75, p¼0.34) over
the 8 weeks. For the intensity of craving item, there were
significant group by linear (GEE model Z-score ¼3.16,
p¼0.002) and group by quadratic (Z-score ¼3.10,
p¼0.002) time effects. Each group showed a decrease in
scores, and the modafinil group showing a greater initial
decline in scores. However, while modafinil group means
were consistently lower than those of the placebo group,
within-time-point contrasts showed no significant group
differences at any point. Similar results were found for the
frequency of craving item: there were significant group by
linear (Z-score ¼2.91, p¼0.004) and group by quadratic
(Z-score ¼3.10, p¼0.002) time effects, but no significant
group differences at any point. There were no significant
treatment group differences in the BCSC intensity
(Z-score ¼0.47, p¼0.64), frequency (Z-score ¼0.35,
p¼0.73), length of time (Z-score ¼0.08, p¼0.94), and
number of times (Z-score ¼1.52, p¼0.13) scales or in the
CCQ total score (Z-score ¼0.76, p¼0.45).
There were no medication-related serious adverse events,
and none of the patients discontinued modafinil due to
adverse events. There were no clinically significant differ-
ences between the two groups with regard to laboratory,
vital sign, electrocardiogram, body weight, or physical
examination findings. Adverse events occurring in at least
5% of modafinil patients, and with at least twice the
incidence of occurrence in placebo patients, included:
nausea (23%), upper respiratory symptoms (17%), anxiety
(13%), tachycardia (13%), urinary tract infection (10%),
dizziness (7%), reduced appetite (7%), racing thoughts
(7%), and dry mouth (7%). None of the patients ascribed
euphoria or cocaine-like effects to the study medications.
Dose reductions due to adverse events were made in six of
30 modafinil-treated patients, from the initial dose of 400 to
300 mg/day (n¼2) or 200 mg/day (n¼4), and adverse
events subsequently resolved in each case (see Table 4).
Dose reductions were not made for any of the placebo-
treated patients.
The current study found that modafinil-treated patients
provided a significantly greater proportion of BE-negative
urine samples than placebo-treated patients over the 8-week
clinical trial. Also, a significantly greater number of
modafinil-treated patients attained the important clinical
goal of protracted cocaine abstinence. It is important to
note that missing urines were imputed as positive in our
analysis. This approach is widely used in cocaine treatment
research, based on the assumption that missing urine
samples are not ignorable (and more likely to be positive),
but it makes clinic attendance an essential factor in the
definition of abstinence and may represent a limitation in
our study. Both groups received an equivalent number of
CBT sessions, further attributing improved outcome to
modafinil administration. Although enrolled patients were
predominantly African Americans living in an urban
setting, other demographic and clinical characteristics are
reasonably consistent with the general cocaine-dependent
population. Modafinil was well tolerated with a dose
Table 4 Clinical Information Regarding Six (20% of Total) Modafinil-Treated Patients Requiring Dose Reductions from the Initial
400 mg/day
Week dose
End dose of
modafinil (mg/day)
Retention after modafinil
Reason for modafinil
dose reduction
#17 3 200 Completed study Insomnia
#19 4 200 Completed week 7 Headache, dizziness
#30 2 300 Completed study Nausea
#43 2 200 Completed week 6 Nausea, Lightheaded
#53 6 200 Completed study Tachycardia
#57 2 300 Completed week 5 Anxiety
A double-blind, placebo-controlled trial of modafinil
CA Dackis et al
titration option, there were no serious adverse events, and
there were no medication-associated dropouts.
Even though modafinil is pharmacologically distinct from
classic psychostimulants (Lin et al, 1996; Ferraro et al,
1997), it is listed on Schedule IV as having mild abuse
potential. Consequently, we carefully monitored the possi-
bility of modafinil overuse and our data showed no
discernible evidence of this phenomenon. None of the
patients enrolled in this study ascribed cocaine-like effects
to their study medication, and blister pack compliance data
showed no evidence of modafinil compared to placebo
overuse. Both groups had a small and equivalent tendency
to retain extra pills that were supplied in their blister packs,
but it is unclear whether the pills were ingested, hoarded,
lost, or otherwise disposed. Still, since pertinent animal
(Gold and Balster, 1996; Deroche-Gamonet et al, 2002) and
human (Jasinski, 2000; Rush et al, 2002a, b) studies suggest
that modafinil might be weakly reinforcing, overuse should
be further assessed in future trials with this population.
None of the secondary efficacy measures attained
significance, although physician-rated improvement
showed a trend (p¼0.06) for the modafinil group. There
was no evidence that modafinil reduced cocaine craving,
which is notoriously difficult to quantify. There was also no
evidence that modafinil reversed cocaine withdrawal, but
our study was not designed to assess this possibility and the
majority of enrolled patients had insignificant cocaine
withdrawal at baseline. Detoxification remains an important
research question because patients with cocaine withdrawal
symptoms have poor clinical outcome (Kampman et al,
2001), and enhanced euphoric responses to cocaine (New-
ton et al, 2003; Sofuoglu et al, 2003). Modafinil promotes
feelings of well-being (Beusterien et al, 1999) has clinical
effects that are largely opposite to cocaine withdrawal
symptoms, and blunts cocaine-induced euphoria. It is
possible that the steady improvement seen in modafinil-
treated patients (see Figure 1) reflects the effect of
diminished reward on their cocaine use.
Although we report significant objective improvement
(clean urines) with modafinil, our results are limited by the
sample size, the subjective nature of craving and withdrawal
questionnaires, and the fact that a substantial proportion of
our patients had a cocaine-negative sample at baseline.
While our assessment of baseline cocaine use might have
been different had we collected multiple urine samples
during screening, it is also possible that our patients had
only moderate addiction severity, and a greater likelihood
of responding to placebo treatment. On the other hand,
although not statistically significant, the modafinil group
had fewer days of cocaine use, fewer cocaine-positive
urines, and lower cocaine withdrawal scores (although
more years of cocaine use), so baseline differences may have
created a disadvantage for the placebo group. Another study
weakness is that medication adherence was only confirmed
by pill counts. Finally, our subjects received manual-guided
CBT, which might not generalize to the clinical setting
where this treatment is seldom available. Nevertheless, we
did find that modafinil significantly improved cocaine
abstinence in this randomized, controlled pilot study,
suggesting that further research should be conducted to
determine whether modafinil might become a first-line
treatment for cocaine dependence.
Financial disclosures: Dr Dackis has participated in the
Cephalon speakers’ bureau. Dr O’Brien was a consultant to
Cephalon approximately 10 years ago.
Author contributions: Dr Dackis, as principal author of
this article, and Dr Lynch, as principal statistician for the
analysis, had full access to all study data and take
responsibility for the integrity of the data and the accuracy
of the data analysis.
Study concept and design: Dackis, Kampman, Pettinati,
O’Brien, Lynch
Statistical expertise: Lynch
Obtained funding: O’Brien, Pettinati
Administrative, technical, or material support: O’Brien,
Pettinati, Kampman
Study supervision: Dackis, O’Brien
Funding/support: Funding for this trial was provided by
the National Institute of Drug Abuse (NIDA) with NIDA
Grants DA P60-05186 and DA P50-12756. Cephalon
provided modafinil and matched placebo tablets.
Investigators: Dackis, Kampman, Pettinati, O’Brien
Role of sponsor: Dr Dackis was the sponsor and was the
principal investigator.
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... In contrast to that, Nuijten et al., 2015, conducted a randomized feasibility trial and revealed the Modafinil did not improve cocaine abstinence, cocaine craving, health, social functioning, and patient satisfaction, and treatment adherence to modafinil was low as well [32]. Confirming the findings, Dackis et al., 2005, found that there were no significant differences in cocaine abstinence, craving, cocaine withdrawal, retention, and tolerability between Modafinil and placebo patients based on a randomized, double-blind, placebo-controlled study. Evidence suggests that Modafinil may not demonstrate favorable clinical outcomes as a treatment for cocaine dependence [33]. ...
... Confirming the findings, Dackis et al., 2005, found that there were no significant differences in cocaine abstinence, craving, cocaine withdrawal, retention, and tolerability between Modafinil and placebo patients based on a randomized, double-blind, placebo-controlled study. Evidence suggests that Modafinil may not demonstrate favorable clinical outcomes as a treatment for cocaine dependence [33]. ...
... Modafinil is a weak inhibitor of dopamine transporter with resulting increases in synaptic dopamine levels (MartinezRaga et al, 2008). Initial clinical trials were promising for both methamphetamine (Shearer et al, 2009) and cocaine (Shearer et al, 2009;Dackis et al, 2005). Subsequent larger randomized trials have been negative, however (Dackis et al, 2012;Anderson et al, 2012). ...
... Though originally developed with the expectation that modafinil could have a non-dopaminergic target for its wake promoting effects, research findings indicate that modafinil also has dopamine-enhancing effects as a mechanism for it therapeutic action (Volkow et al., 2009). These findings not only warn of the risk of methylphenidate abuse by non-prescription users, but also state that reports of its abuse are rare and that its potential to reduce regular cocaine and methamphetamine use needs to be researched further (Battleday & Brem, 2015;Dackis et al., 2005;Volkow et al., 2009). ...
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The global rise in methamphetamine use and its negative effects warrants the need for research exploring harm reduction and treatment interventions for individuals with methamphetamine use disorder. Agonist medications have been utilized for years for the treatment of heroin and opioid addiction, but have yet to be incorporated into mainstream Canadian practice for methamphetamine dependence. This review aims to provide an overview of the current trends of prescription psychostimulant usage for individuals with methamphetamine use disorder from a Canadian perspective, identifies the barriers to accessing prescription psychostimulants for methamphetamine use disorder and highlights the nursing clinical practice implications in caring for individuals with the disorder. Discourse on the sustained abstinence and harm reduction debate is presented from the perspective of methamphetamine abuse is provided along with the neuropsychiatric complications of chronic methamphetamine use. The impacts of specific prescription psychostimulants on cognition are discussed as is the use of neuroimaging techniques to assess neuronal damage in methamphetamine users. Sign of toxicity, overdose and the contraindications for use of these prescription psychostimulants is also presented. The implications to nursing clinical practice in caring for this population is provided, touching on the clinical presentation of methamphetamine use, completing thorough assessment and screening and patient education. The findings of this review indicate the need for further research in this area exploring the benefits of prescription psychostimulants as a harm reduction and treatment intervention for the global problem of methamphetamine dependence.
Frontiers in Clinical Drug Research - CNS and Neurological Disorders is a book series that brings updated reviews to readers interested in advances in the development of pharmaceutical agents for the treatment of central nervous system (CNS) and other nerve disorders. The scope of the book series covers a range of topics including the medicinal chemistry, pharmacology, molecular biology and biochemistry of contemporary molecular targets involved in neurological and CNS disorders. Reviews presented in the series are mainly focused on clinical and therapeutic aspects of novel drugs intended for these targets. Frontiers in Clinical Drug Research - CNS and Neurological Disorders is a valuable resource for pharmaceutical scientists and postgraduate students seeking updated and critical information for developing clinical trials and devising research plans in the field of neurology. The eleventh volume of this series features reviews that cover the following topics related to the treatment of a variety of CNS disorders, related diseases, and basic research: The Multi-target Directed Ligands candidate (MTDLs) prototypes for neurodegenerative diseases Drugs for relapse prevention in addiction Neuroprotective activities of cinnamic acids and their derivatives in neurodegenerative disorders Phytosome for targeted delivery of natural compounds in treating alzheimer's disease Physical activity as a non-pharmacologic method for treatment of alzheimer's disease
Despite the lack of guidance available for practitioners, extensive polypharmacy has become the primary method of treating patients with severe and chronic mood, anxiety, psychotic or behavioral disorders. This ground-breaking new book provides an overview of psychopharmacology knowledge and decision-making strategies, integrating findings from evidence-based trials with real-world clinical presentations. It adopts the approach and mind-set of a clinical investigator and reveals how prescribers can practice 'bespoke psychopharmacology', tailoring care to the individualized needs of patients. Practitioners at all levels of expertise will enhance their ability to devise rationale-based treatments, targeting manifestations of dysfunctional neural circuitry and dimensions of psychopathology that cut across conventional psychiatric diagnoses. Presented in a user-friendly, practical, full-colour layout and incorporating summary tables, bullet points, and illustrative case vignettes, it is an invaluable guide for all healthcare professionals prescribing psychotropic medications, including psychiatry specialists, primary care physicians, and advanced practice registered nurses.
While there are no FDA-approved treatments for cocaine use disorder (CUD), several modafinil analogs have demonstrated promise in reducing cocaine self-administration and reinstatement in rats. Furthermore, the range of dopamine transporter (DAT) compounds provides an opportunity to develop pharmacotherapeutics without abuse liability. This study extended the comparison of JJC8-088 and JJC8-091, the former compound having higher DAT affinity and predicted abuse liability, to rhesus monkeys using a concurrent cocaine-food schedule of reinforcement. First, binding to striatal DAT was examined in cocaine-naïve monkey tissue. Next, i.v. pharmacokinetics of both JJC compounds were evaluated in cocaine-experienced male monkeys (n=3/drug). In behavioral studies, acute and chronic administration of both compounds were evaluated in these same monkeys responding under a concurrent food vs. cocaine (0, 0.003-0.1 mg/kg/injection) schedule of reinforcement. In nonhuman primate striatum, JJC8-088 had higher DAT affinity compared to JJC8-091 (14.4 {plus minus} 9 vs. 2,730 {plus minus} 1,270 nM, respectively). Both JJC compounds had favorable plasma pharmacokinetics for behavioral assessments, with half-lives (t1/2) of 1.1 h and 3.5 h for JJC8-088 (0.7 mg/kg, i.v.) and JJC8-091 (1.9 mg/kg, i.v.), respectively. Acute treatment with both compounds shifted the cocaine dose-response curve to the left. Chronic treatment with JJC8-088 decreased cocaine choice in two of the three monkeys, while JJC8-091 only modestly reduced cocaine allocation in one monkey. Differences in affinities of JJC8-091 DAT binding in monkeys compared to rat, may account for the poor rodent-to-monkey translation. Future studies should evaluate atypical DAT blockers in combination with behavioral interventions that may further decrease cocaine choice. Significance Statement Cocaine use disorder (CUD) remains a significant public health problem with no FDA-approved treatments. The ability of drugs that act in the brain in a similar manner to cocaine, but with lower abuse liability, has clinical implications for a treatment of CUD.
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Much experimental and clinical data suggest that the pharmacological profile of modafinil, a newly discovered waking substance, differs from those of amphetamine and methylphenidate, two classical psychostimulants. The brain targets on which modafinil acts to induce wakefulness, however, remain unknown. A double-blind study using the protooncogene c-fos as experimental marker in the cat was, therefore, carried out to identify the potential target neurons of modafinil and compare them with those for amphetamine and methylphenidate. Cats were sacrificed after a single oral administration of amphetamine, methylphenidate, or modafinil at equivalent doses for wake induction (1, 2.5, or 5 mgykg, respectively) and brain sections examined for Fos by immunocytochemistry. Administration of either amphetamine or methylphenidate evoked Fos-like immunoreactivity in a large number of neurons in the striatum and whole cortex, especially in the caudate nucleus and mediofrontal cortex, which are known to be dopaminergic targets. In contrast, administration of modafinil resulted in the labeling of few cells in these structures, but did induce marked Fos labeling in neurons of the anterior hypothalamic nucleus and adjacent areas. These results provide evidence for the potential brain targets of modafinil, which differ from those of amphetamine or methylphenidate, and suggest that modafinil induces wakefulness by mechanisms distinct from those of the two stimulants.
Alterations in the density of GABA and glutamate immunolabeling within nerve terminals in the shell region of the nucleus accumbens were assessed in rats withdrawn from intravenous cocaine exposure. Four groups of rats were used: one group self‐administered cocaine (0.42 mg/ kg/ infusion) in daily 3‐h sessions for approximately 2 weeks, two additional groups received either saline or cocaine in a noncontingent fashion, and a fourth comprised a drug‐naive, age‐matched control group. Immunogold electron microscopy was used to quantify presynaptic terminal GABA and glutamate density within the vesicular and mitochondrial pools approximately 18 days following the last drug or saline exposure in the treatment groups. A significant 27.7% decrease in vesicular glutamate density within asymmetrical nerve terminals was observed in animals that self‐administered cocaine as compared to controls. This group also showed an 18.6% decrease in vesicular nerve terminal glutamate immunolabeling as compared to animals that were administered a similar total dose of cocaine in a response‐independent fashion. No significant changes in the density of nerve terminal GABA vesicular immunolabeling were observed in any groups. For both transmitters, no differences were detected in the density of immunolabeling within the presynaptic mitochondrial (i.e., metabolic) pool. These results demonstrate that glutamate density is suppressed in the shell region of the nucleus accumbens following withdrawal from 2 weeks of cocaine exposure. The findings also suggest that the motivational aspects that accompany self‐administration may participate in this reduction. Synapse 30:393–401, 1998. © 1998 Wiley‐Liss, Inc.