Cocaine Use DisorderPhase 2NCT05529927
Efficacy and Safety of Sustained-release Dexamphetamine in Patients With Moderate to Severe Cocaine Use Disorder
A Phase 2 study testing Sustained-release Dexamphetamine in people with Cocaine Use Disorder, run by Parnassia Addiction Research Centre at 1 site in Netherlands.
Trial summary
In The Netherlands, each year, about 15 thousand people come into treatment because of problems with cocaine use. There is no approved medication for treatment of cocaine addiction and the psychosocial treatment patients receive is not successful for everyone; many return to treatment several times. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Cocaine Use Disorder
- What is being tested?
- Sustained-release Dexamphetamine
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 204 participants
- Where
- 1 siteNetherlands
- Study dates
- 22 Apr 2026to Oct 2029
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- male and female patients between 18 years and over;
- actively participating in opioid agonist treatment with oral methadone;
- with moderate or severe cocaine use disorder according to DSM-5;
- with regular use of cocaine in the previous month (i.e., ≥8 days/month);
- with snorting, inhaling or injecting cocaine use as primary route of administration;
- express the intention to reduce or stop their cocaine use;
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- be able and willing to attend the treatment center for 2 days per week;
- be able and willing to co-operate with the required study assessments and study procedures; and
- have provided written informed consent.
Who cannot join
- severe medical (e.g., severe renal or hepatic insufficiency/failure) or severe psychiatric problems (e.g. previous or acute severe psychotic episode, acute suicidality, current bipolar disorder);
- cardiovascular problems: clinically relevant ECG abnormalities suggestive of channelopathy or structural or ischemic heart disease, or a prolonged QTc interval (≥500 msec); moderate to severe hypertension (i.e., SBP>140; DBP>90); HR>100, known coronary artery disease (i.e., angina pectoris, acute myocardiac infarction), known cardiomyopathy, CVA;
- glaucoma;
- Gilles-de-la-Tourette syndrome;
- pheochromocytoma;
- hyperthyroid status;
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- pregnancy or continued lactation;
- use of monoamine oxidase inhibitor(s) (MAOI): currently or in the past 14 days;
- treatment with other prescription psychostimulants that might potentially be effective for stimulant use disorder (i.e., (immediate release) dexamphetamine, lisdexamphetamine, methylphenidate, or modafinil);
- anticipated need for inpatient treatment (clinical judgement);
- (expected) inability to complete the 30 weeks study (e.g., planned holidays, expected incarceration or hospitalization);
- insufficient command of the Dutch language; and
- current participation in another addiction treatment study.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Netherlands1 site, 1 recruiting
- Recruiting
Brijder Den Haag
The Hague, 2512 HN
Tjitske Colenbrander, MD, +31616046159, t.colenbrander@brijder.nl
About this study
Official title: Efficacy and Safety of 24 Weeks Sustained-release Dexamphetamine in Patients With Moderate to Severe Cocaine Use Disorder With Comorbid Opioid Use Disorder - A Multicenter Randomized, Double-blind, Placebo-controlled Study
In The Netherlands, each year, about 15 thousand people come into treatment because of problems with cocaine use. There is no approved medication for treatment of cocaine addiction and the psychosocial treatment patients receive is not successful for everyone; many return to treatment several times. There is evidence that agonist ("replacement") medications are effective in treating addiction: methadone for heroin addiction; nicotine replacement for smokers. Dexamphetamine is a stimulant medication registered for treatment of ADHD. It may also be effective as agonist treatment for people with cocaine addiction.
It will be investigated whether sustained-release dexamphetamine in people with cocaine addiction, participating in routine methadone maintenance treatment for their comorbid opioid use disorder, (1) reduces cocaine use and (2) improves their health and quality of life.
Read the detailed description
RESEARCH QUESTION/RATIONALE: Treatment for patients with cocaine use disorder is modestly effective and there is an urgent need for more effective treatments. Several randomized controlled trials, including our previous proof of principle study (Nuijten et al., 2016, The Lancet), suggest that sustained-release dexamphetamine is the most promising medication for the treatment of cocaine use disorder.
HYPOTHESIS \& OBJECTIVES: Therefore, it is hypothesized that sustained-release dexamphetamine is effective in patients with cocaine use disorder in terms of reducing cocaine use and improving health and quality of life.
STUDY DESIGN: Multicentre randomized, double-blind, placebo-controlled study in 204 patients with cocaine use disorder - participating in routine methadone maintenance treatment for their comorbid opioid use disorder. In the 1st study phase (24 weeks) the efficacy and safety of sustained-release dexamphetamine is compared with placebo. In the 2nd double-blind, placebo-controlled randomized treatment discontinuation phase (6 weeks), we assess the consequences of discontinuation of sustained-release dexamphetamine treatment.
STUDY POPULATION: Patients with moderate/severe cocaine use disorder participating in routine oral methadone maintenance treatment for their comorbid opioid use disorder .
INTERVENTION: The investigational product is in tablets, containing 30 mg dexamphetamine sulphate in sustained-release formulation. Patients will be titrated to the target dose of 90 mg/day, if tolerated. Medication is dispensed twice weekly.
OUTCOME PARAMETERS: Primary endpoint: number of days of cocaine abstinence in the final 4 weeks of treatment, assessed by combined self-report and urinalysis. Key secondary endpoint: Good or improved overall health status (in terms of physical and mental health, and social functioning).
SAMPLE SIZE/DATA-ANALYSIS: Assuming 5 days difference in cocaine abstinent days in the final 4 weeks of the study to be clinically relevant requires 102 patients per treatment group in order to detect these 5 days difference (pooled standard deviation: 11 days; two-sided alpha=0.05; power=0.90). Primary analysis: As cocaine abstinence is assessed throughout the trial, the numbers of days of cocaine abstinence in the sequential 4 week periods will be treated as repeated measure. The primary analysis will be a likelihood-based mixed model of repeated measures (MMRM) approach, including treatment, fixed timepoints (periods of 4 weeks, categorical) and their interaction as fixed factors and subject as random effect. Treatment center and overall health status (both stratification factors) will be included as covariates. The contrast between the two groups at week 24 will be the primary comparison.
- Conditions
- Cocaine Use Disorder
- Being tested
- Sustained-release Dexamphetamine, Placebo
- Keywords
- cocaine use disorder, sustained-release dexamphetamine, agonist pharmacotherapy, opioid use disorder, methadone maintenance treatment, randomized controlled trial (RCT), placebo-controlled, double-blind
- Medical subject headings
- Opioid-Related Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Sustained-release DexamphetamineDrug
During the first week, patients will be individually titrated to the target dose of 90 mg/day, if tolerated. From the second week onwards, patients are prescribed 3 tablets (30 mg) per day, if tolerated. Titration can be slower but should be finished at the end of week 4. After 4 weeks dosages can no longer be increased, and only be reduced.
Patients will visit the treatment centre 2 times per week to take their study medication under supervision of the treatment staff and to receive take-home medication for the days in between study visits.
After 24 weeks patients will be randomized to either (double-blind) continuation or discontinuation (placebo) of SR-Dexamphetamine treatment to assess the consequences of discontinuation, during a 6 weeks period.
PlaceboDrug
Dispensed under the same conditions and with similar frequency as the investigational product (see above).
After 24 weeks study medication will be discontinued in the placebo group.
| Study group | Role | What they receive |
|---|---|---|
| Sustained-release Dexamphetamine | Experimental | Tablets of 30 mg sustained-release dexamphetamine sulphate. Target dose: 90 mg/day, if tolerated. Tablets have to be taken daily, in the morning, per os for 24 weeks. Receives: Drug: Sustained-release Dexamphetamine |
| Placebo | Placebo comparator | Identical matched placebo, dispensed under the same conditions and with similar frequency as the investigational product (see above). Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Primary outcome measure for the primary study objective (to evaluate the efficacy of 24 weeks SR-dexamphetamine, compared with 24 weeks placebo): the number of days cocaine abstinence.
The number of days of cocaine abstinence in the final 4 weeks of treatment, assessed by combined self-report and urinalysis.
Measured: Final 4 weeks of treatment (first study phase; i.e., week 21-24)
Secondary outcomes (13)
Key secondary outcome measure for the primary study objective ("good or improved overall health status", in terms of physical health, mental health, and social functioning).
Good or improved overall health is defined as follows:
- In patients with physical health problems (Maudsley Addiction Profile; MAP-HSS), or mental health problems (Brief Symptom Inventory; BSI) or problematic social functioning (Social functioning, criminality; European Addiction Severity Index; EuropASI) at baseline, good or improved overall health is defined as: at least 40% improvement in at least one of the 'problematic' health domains, compared with baseline status, assessed at week 24.
- In patients without physical health problems, or mental health problems or problematic social functioning at baseline, good or improved overall health is defined as: no deterioration of 40% or more in any of the 'non-problematic' health domains, compared with baseline status, that results in crossing the threshold of health problems, again assessed at week 24.
This endpoint concerns the 24-week efficacy of SR-dexamphetamine in terms of overall health.
Measured: Final 4 weeks of treatment (i.e. week 21 - week 24) compared with baseline
Secondary outcome measures for the primary study objective: Cocaine use related secondary endpoints: (1) Total number of days cocaine abstinence.
Measured: During first 12 weeks treatment (i.e., 0-84 days)
Secondary outcome measures for the primary study objective: Cocaine use related secondary endpoints: (2) Total number of days cocaine abstinence.
Measured: During 24 weeks treatment (i.e., 0-168 days)
Secondary outcome measures for the primary study objective: Cocaine use related secondary endpoints: (3) Complete abstinence from cocaine.
Measured: During 24 weeks treatment
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (4) Achieving a period of sustained abstinence from cocaine for at least 21 consecutive days.
Proportion of subjects achieving sustained cocaine abstinence of at least 21 consecutive days as measured by the Timeline Follow-Back Method (TLFB): SR-dexamphetamine versus placebo. Higher proportion means better outcome.
Measured: During 24 weeks treatment
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (5) At least 40% reduction in cocaine use (days/month) in the final 4 weeks of treatment (weeks 21-24), compared with baseline.
Measured: The final 4 weeks of treatment (weeks 21-24)
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (6) Number of weeks of uninterrupted cocaine abstinence sustained till abstinence during final treatment week in study phase 1.
Measured: Final treatment week in study phase 1
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (7) Average number of cocaine administrations on days that cocaine was used.
Measured: During 24 weeks treatment
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (8) Cocaine craving.
Cocaine craving is measured using the Obsessive Compulsive Drug Use Scale (OCDUS, Franken et al., 2002), with a score range of 0 to 20. Higher scores mean worse outcome.
Measured: During 24 weeks treatment
Secondary outcome measure for the secondary study objective (to assess the acceptance, tolerability, and safety of 24 weeks SR-dexamphetamine): treatment completion; medication adherence; adverse events, and serious adverse events.
- The number and proportion of patients starting and completing 24 weeks treatment;
- Maximum dose received; dose at the end of week 4; dose in final 4 weeks of study phase 1 (weeks 21-24); dose in final 4 weeks of study phase 2 (weeks 27-30) (all: mean(std.dev), and median/IQR).
- Safety will be assessed and reported in terms of:
- Vital signs (heart rate, blood pressure) and body weight.
- ECG and safety laboratory parameters (NT-proBNP, and hs-Troponine T).
- Adverse events (AEs; solicited and unsolicited) and serious adverse events (SAEs).
Measured: The first 24 weeks of treatment
Secondary outcome measure for the secondary study objective (to evaluate the effect of discontinuation of SR-dexamphetamine after 24 weeks treatment): days cocaine abstinence.
Days cocaine abstinence in the final 4 weeks of the discontinuation phase of the study (i.e., weeks 27-30), assessed by combined self-report and urinalysis. A decrease of ≥5 days/month in cocaine abstinent days, compared with the number of cocaine abstinent days/month at the end of study phase 1 (weeks 21-24) is considered to be a clinically relevant deterioration.
Measured: Final 4 weeks of treatment discontinuation phase (second study phase; i.e., week 27-30)
Secondary outcome measure for the secondary study objective (to evaluate the effect of discontinuation of SR-dexamphetamine after 24 weeks treatment): overall health status.
The overall health status of patients in the final 4 weeks of the discontinuation study phase 2 (weeks 27-30), - defined as "deteriorated overall health status", in terms of physical health, mental health, and social functioning - thereby using the overall health status at the end of study phase 1 (weeks 21-24) as reference. More specifically, deteriorated overall health status is defined as follows: In patients without physical health problems, or mental health problems or problematic social functioning at week 24, deteriorated overall health status is defined as: a deterioration of 40% or more in any of the 'non-problematic' health domains, compared with status at week 24, that results in crossing the threshold of health problems, assessed at week 30.
Measured: Final 4 weeks of treatment discontinuation phase (second study phase; i.e., week 27-30)
Secondary outcome measure for the secondary study objective (to evaluate the effect of discontinuation of SR-dexamphetamine after 24 weeks treatment): dichotomous outcome of deterioration.
A dichotomous outcome of deterioration (yes versus no) based on the composite outcome of (1) a clinically relevant decrease of ≥5 days/month in cocaine abstinent days and/or (2) deterioration in overall health status.
Measured: Final 4 weeks of treatment discontinuation phase (second study phase; i.e., week 27-30)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Sep 2022
- Study start22 Apr 2026
- Primary completionJan 2029 (estimated)
- Study completionOct 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Cocaine Use DisorderStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 204 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Parnassia Addiction Research Centre
- Sponsor type
- University, hospital or other
- Collaborators
- Leiden University Medical Center, Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA), Radboud University Medical Center, The Netherlands Cancer Institute, Het Zwarte Gat
- Responsible party
- Principal investigator, Vincent Hendriks, Parnassia Addiction Research Centre
- Investigators
- Vincent Hendriks, PhD., Principal investigator, Parnassia Addiction Research Centre
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05529927
- Sponsor's protocol ID
- 10140262110025
- Status last verified
- May 2026
- First submitted
- 19 Aug 2022
- Last updated
- 29 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Coded IPD will become available upon reasonable request. Procedures have not yet been determined.
Publications
Nuijten M, Blanken P, van de Wetering B, Nuijen B, van den Brink W, Hendriks VM. Sustained-release dexamfetamine in the treatment of chronic cocaine-dependent patients on heroin-assisted treatment: a randomised, double-blind, placebo-controlled trial. Lancet. 2016 May 28;387(10034):2226-34. doi: 10.1016/S0140-6736(16)00205-1. Epub 2016 Mar 22.
PubMed 27015909Blanken P, Nuijten M, van den Brink W, Hendriks VM. Clinical effects beyond cocaine use of sustained-release dexamphetamine for the treatment of cocaine dependent patients with comorbid opioid dependence: secondary analysis of a double-blind, placebo-controlled randomized trial. Addiction. 2020 May;115(5):917-923. doi: 10.1111/add.14874. Epub 2020 Jan 6.
PubMed 31908066
Study at a glance
From the registry record, last updated by the sponsor on 29 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Efficacy and Safety of 24 Weeks Sustained-release Dexamphetamine in Patients With Moderate to Severe Cocaine Use Disorder With Comorbid Opioid Use Disorder - A Multicenter Randomized, Double-blind, Placebo-controlled Study
- ClinicalTrials.gov ID
- NCT05529927
- Acronym / sponsor ID
- 10140262110025
- Conditions
- Cocaine Use Disorder
- Keywords
- cocaine use disorder, sustained-release dexamphetamine, agonist pharmacotherapy, opioid use disorder, methadone maintenance treatment, randomized controlled trial (RCT), placebo-controlled, double-blind
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 204 participants (estimated)
- Lead sponsor
- Parnassia Addiction Research CentreUniversity, hospital or other
- Collaborators
- Leiden University Medical Center, Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA), Radboud University Medical Center, The Netherlands Cancer Institute, Het Zwarte Gat
- Study start
- 22 Apr 2026 (actual)
- Primary completion
- Jan 2029 (estimated)
- Study completion
- Oct 2029 (estimated)
- First posted
- 7 Sep 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
In The Netherlands, each year, about 15 thousand people come into treatment because of problems with cocaine use. There is no approved medication for treatment of cocaine addiction and the psychosocial treatment patients receive is not successful for everyone; many return to treatment several times. There is evidence that agonist ("replacement") medications are effective in treating addiction: methadone for heroin addiction; nicotine replacement for smokers. Dexamphetamine is a stimulant medication registered for treatment of ADHD. It may also be effective as agonist treatment for people with cocaine addiction.
It will be investigated whether sustained-release dexamphetamine in people with cocaine addiction, participating in routine methadone maintenance treatment for their comorbid opioid use disorder, (1) reduces cocaine use and (2) improves their health and quality of life.
Detailed description
RESEARCH QUESTION/RATIONALE: Treatment for patients with cocaine use disorder is modestly effective and there is an urgent need for more effective treatments. Several randomized controlled trials, including our previous proof of principle study (Nuijten et al., 2016, The Lancet), suggest that sustained-release dexamphetamine is the most promising medication for the treatment of cocaine use disorder.
HYPOTHESIS \& OBJECTIVES: Therefore, it is hypothesized that sustained-release dexamphetamine is effective in patients with cocaine use disorder in terms of reducing cocaine use and improving health and quality of life.
STUDY DESIGN: Multicentre randomized, double-blind, placebo-controlled study in 204 patients with cocaine use disorder - participating in routine methadone maintenance treatment for their comorbid opioid use disorder. In the 1st study phase (24 weeks) the efficacy and safety of sustained-release dexamphetamine is compared with placebo. In the 2nd double-blind, placebo-controlled randomized treatment discontinuation phase (6 weeks), we assess the consequences of discontinuation of sustained-release dexamphetamine treatment.
STUDY POPULATION: Patients with moderate/severe cocaine use disorder participating in routine oral methadone maintenance treatment for their comorbid opioid use disorder .
INTERVENTION: The investigational product is in tablets, containing 30 mg dexamphetamine sulphate in sustained-release formulation. Patients will be titrated to the target dose of 90 mg/day, if tolerated. Medication is dispensed twice weekly.
OUTCOME PARAMETERS: Primary endpoint: number of days of cocaine abstinence in the final 4 weeks of treatment, assessed by combined self-report and urinalysis. Key secondary endpoint: Good or improved overall health status (in terms of physical and mental health, and social functioning).
SAMPLE SIZE/DATA-ANALYSIS: Assuming 5 days difference in cocaine abstinent days in the final 4 weeks of the study to be clinically relevant requires 102 patients per treatment group in order to detect these 5 days difference (pooled standard deviation: 11 days; two-sided alpha=0.05; power=0.90). Primary analysis: As cocaine abstinence is assessed throughout the trial, the numbers of days of cocaine abstinence in the sequential 4 week periods will be treated as repeated measure. The primary analysis will be a likelihood-based mixed model of repeated measures (MMRM) approach, including treatment, fixed timepoints (periods of 4 weeks, categorical) and their interaction as fixed factors and subject as random effect. Treatment center and overall health status (both stratification factors) will be included as covariates. The contrast between the two groups at week 24 will be the primary comparison.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Sustained-release Dexamphetamine | Experimental | Drug: Sustained-release DexamphetamineTablets of 30 mg sustained-release dexamphetamine sulphate. Target dose: 90 mg/day, if tolerated. Tablets have to be taken daily, in the morning, per os for 24 weeks. |
| Placebo | Placebo comparator | Drug: PlaceboIdentical matched placebo, dispensed under the same conditions and with similar frequency as the investigational product (see above). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- male and female patients between 18 years and over;
- actively participating in opioid agonist treatment with oral methadone;
- with moderate or severe cocaine use disorder according to DSM-5;
- with regular use of cocaine in the previous month (i.e., ≥8 days/month);
- with snorting, inhaling or injecting cocaine use as primary route of administration;
Key exclusion criteria (13 listed)
- severe medical (e.g., severe renal or hepatic insufficiency/failure) or severe psychiatric problems (e.g. previous or acute severe psychotic episode, acute suicidality, current bipolar disorder);
- cardiovascular problems: clinically relevant ECG abnormalities suggestive of channelopathy or structural or ischemic heart disease, or a prolonged QTc interval (≥500 msec); moderate to severe hypertension (i.e., SBP>140; DBP>90); HR>100, known coronary artery disease (i.e., angina pectoris, acute myocardiac infarction), known cardiomyopathy, CVA;
- glaucoma;
- Gilles-de-la-Tourette syndrome;
- pheochromocytoma;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Sustained-release DexamphetamineDuring the first week, patients will be individually titrated to the target dose of 90 mg/day, if tolerated. From the second week onwards, patients are prescribed 3 tablets (30 mg) per day, if tolerated. Titration can be slower but should be finished at the end of week 4. After 4 weeks dosages can no longer be increased, and only be reduced. Patients will visit the treatment centre 2 times per week to take their study medication under supervision of the treatment staff and to receive take-home medication for the days in between study visits. After 24 weeks patients will be randomized to either (double-blind) continuation or discontinuation (placebo) of SR-Dexamphetamine treatment to assess the consequences of discontinuation, during a 6 weeks period. | Drug | Sustained-release Dexamphetamine |
| PlaceboDispensed under the same conditions and with similar frequency as the investigational product (see above). After 24 weeks study medication will be discontinued in the placebo group. | Drug | Placebo |
Primary outcome
Primary outcome measure for the primary study objective (to evaluate the efficacy of 24 weeks SR-dexamphetamine, compared with 24 weeks placebo): the number of days cocaine abstinence.
Time frame: Final 4 weeks of treatment (first study phase; i.e., week 21-24)
The number of days of cocaine abstinence in the final 4 weeks of treatment, assessed by combined self-report and urinalysis.
13 secondary outcomes
Key secondary outcome measure for the primary study objective ("good or improved overall health status", in terms of physical health, mental health, and social functioning).
Time frame: Final 4 weeks of treatment (i.e. week 21 - week 24) compared with baseline
Secondary outcome measures for the primary study objective: Cocaine use related secondary endpoints: (1) Total number of days cocaine abstinence.
Time frame: During first 12 weeks treatment (i.e., 0-84 days)
Secondary outcome measures for the primary study objective: Cocaine use related secondary endpoints: (2) Total number of days cocaine abstinence.
Time frame: During 24 weeks treatment (i.e., 0-168 days)
Secondary outcome measures for the primary study objective: Cocaine use related secondary endpoints: (3) Complete abstinence from cocaine.
Time frame: During 24 weeks treatment
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (4) Achieving a period of sustained abstinence from cocaine for at least 21 consecutive days.
Time frame: During 24 weeks treatment
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (5) At least 40% reduction in cocaine use (days/month) in the final 4 weeks of treatment (weeks 21-24), compared with baseline.
Time frame: The final 4 weeks of treatment (weeks 21-24)
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (6) Number of weeks of uninterrupted cocaine abstinence sustained till abstinence during final treatment week in study phase 1.
Time frame: Final treatment week in study phase 1
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (7) Average number of cocaine administrations on days that cocaine was used.
Time frame: During 24 weeks treatment
Secondary outcome measures for the primary study objective: Cocaine use related endpoints: (8) Cocaine craving.
Time frame: During 24 weeks treatment
Secondary outcome measure for the secondary study objective (to assess the acceptance, tolerability, and safety of 24 weeks SR-dexamphetamine): treatment completion; medication adherence; adverse events, and serious adverse events.
Time frame: The first 24 weeks of treatment
Secondary outcome measure for the secondary study objective (to evaluate the effect of discontinuation of SR-dexamphetamine after 24 weeks treatment): days cocaine abstinence.
Time frame: Final 4 weeks of treatment discontinuation phase (second study phase; i.e., week 27-30)
Secondary outcome measure for the secondary study objective (to evaluate the effect of discontinuation of SR-dexamphetamine after 24 weeks treatment): overall health status.
Time frame: Final 4 weeks of treatment discontinuation phase (second study phase; i.e., week 27-30)
Secondary outcome measure for the secondary study objective (to evaluate the effect of discontinuation of SR-dexamphetamine after 24 weeks treatment): dichotomous outcome of deterioration.
Time frame: Final 4 weeks of treatment discontinuation phase (second study phase; i.e., week 27-30)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 May 2026.
- Background: PubMed 27015909Nuijten M, Blanken P, van de Wetering B, Nuijen B, van den Brink W, Hendriks VM. Sustained-release dexamfetamine in the treatment of chronic cocaine-dependent patients on heroin-assisted treatment: a randomised, double-blind, placebo-controlled trial. Lancet. 2016 May 28;387(10034):2226-34. doi: 10.1016/S0140-6736(16)00205-1. Epub 2016 Mar 22.
- Background: PubMed 31908066Blanken P, Nuijten M, van den Brink W, Hendriks VM. Clinical effects beyond cocaine use of sustained-release dexamphetamine for the treatment of cocaine dependent patients with comorbid opioid dependence: secondary analysis of a double-blind, placebo-controlled randomized trial. Addiction. 2020 May;115(5):917-923. doi: 10.1111/add.14874. Epub 2020 Jan 6.
- Individual participant dataSharing planned: Yes. Coded IPD will become available upon reasonable request. Procedures have not yet been determined.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Vincent Hendriks, PhD. principal investigator
Parnassia Addiction Research Centre
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Sustained-release Dexamphetamine in people with Cocaine Use Disorder, run by Parnassia Addiction Research Centre at 1 site in Netherlands.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 29 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Netherlands. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Vincent Hendriks, PhD. (+31651154583, vincent.hendriks@brijder.nl), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Primary outcome measure for the primary study objective (to evaluate the efficacy of 24 weeks SR-dexamphetamine, compared with 24 weeks placebo): the number of days cocaine abstinence. (time frame: Final 4 weeks of treatment (first study phase; i.e., week 21-24)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05529927, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 May 2026; AzTrials last refreshed its copy on 7 Nov 2026.