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DTA (Dopaminergic Therapy for Anhedonia) Study

Dopaminergic Therapy for Inflammation-Related Anhedonia in Depression

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04723147
Enrollment
19
Registered
2021-01-25
Start date
2021-01-29
Completion date
2023-10-11
Last updated
2024-12-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Anhedonia, Depression

Keywords

Depression, Anhedonia

Brief summary

The purpose of this 6-week, double-blind, placebo-controlled, crossover study is to explore new treatment options for people with depression who have high inflammation and anhedonia. Thirty-five male and female participants with depression, between the ages of 25-55 years of age, will be randomized to two study tracks (A and B) to receive both placebo and three doses of L-DOPA, given in different orders. Increases or decreases in each dose will occur gradually over 6 weeks of the study. Participants will complete lab tests, medical and psychiatric assessments, neurocognitive testing and functional MRI (fMRI) scans as part of the study. The total length of participation is about 2 months.

Detailed description

Depression is a widespread disorder (lifetime prevalence \>20%). Current antidepressant medications are effective for many patients; however, more than 30% fail to respond. Of the patients that do respond to treatment, some continue to suffer with primary symptoms of depression like an inability to experience pleasure, called anhedonia. In this regard, one biological pathway that may contribute to symptoms of depression and particularly anhedonia is inflammation. The purpose of this 6-week, double-blind, placebo-controlled, crossover study is to explore new treatment options for people with depression who have high inflammation and anhedonia. Despite evidence of low dopamine function in patients with depression, the ability of existing dopaminergic therapies, like L-DOPA, to affect brain circuits in depression has yet to be explored. This study will help determine the best dose of an FDA-approved medication, Sinemet (L-DOPA) that might be used in the future to treat sub-groups of depressed individuals. Forty male and female participants with depression, between the ages of 25-55 years of age, will be randomized to two study tracks (A and B) to receive both placebo and three doses of L-DOPA, given in different orders. Increases or decreases in each dose will occur gradually over 6 weeks of the study. Participants will complete lab tests, medical and psychiatric assessments, neurocognitive testing and functional MRI (fMRI) scans as part of the study. The total length of participation is about 2 months.

Interventions

Patients will receive L-DOPA at doses ranging from 150 to 450 mg administered at a ratio of 1 mg carbidopa for every 4 mg L-DOPA. Starting dose is 150 mg/day with dose escalation 150 mg/day per week to a final dose of 450 mg/day

DRUGPlacebo

A placebo is a sugar pill that has no therapeutic effect and will be administered orally. Participants will receive 1 placebo tablet matching the Carbidopa Levodopa tablet.

Sponsors

National Institute of Mental Health (NIMH)
CollaboratorNIH
Emory University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
25 Years to 55 Years
Healthy volunteers
No

Inclusion criteria

* willing and able to give written informed consent; * men or women, 25-55 years of age * a primary diagnosis of DSM-V MD, current, as diagnosed by the SCID-I; * score \>10 on the Patient Health Questionnaire \[PHQ\]-9 * off all antidepressant or other psychotropic therapy (e.g. mood stabilizers, antipsychotics, anxiolytics, and sedative hypnotics) for at least 4 weeks prior to baseline visit (8 weeks for fluoxetine) * CRP ≥2 mg/L * Score \>/=2 on the anhedonia question of Patient Health Questionnaire \[PHQ\]-9

Exclusion criteria

* history or evidence (clinical or laboratory) of an autoimmune disorder ; * history or evidence (clinical or laboratory) of hepatitis B or C infection or human immunodeficiency virus infection; - history of any type of cancer requiring treatment with more than minor surgery; * unstable cardiovascular, endocrinologic, hematologic, hepatic, renal, or neurologic disease (as determined by physical examination, EKG and laboratory testing); * history of any (non-mood-related) psychotic disorder; active psychotic symptoms of any type; history or current bipolar disorder; history or current gambling disorder; substance abuse/dependence within 6 months of study entry (as determined by SCID); * active suicidal plan as determined by a score \>3 on item #3 on the HAM-D; g. an active eating disorder (except for patients with binge eating disorder in whom binging is clearly associated with worsening of mood symptoms) ; * a history of a cognitive disorder * pregnancy or lactation; * chronic use of non-steroidal anti-inflammatory agents (NSAIDS) (excluding 81mg of aspirin), glucocorticoid containing medications or statins; * use of NSAIDS, glucocorticoids, or statins at any time during the study; * urine toxicology screen is positive for drugs of abuse, * any contraindication for MRI scanning; n. intolerance, sensitivity or contraindication to carbidopa-levodopa (including history of narrow-angle glaucoma, melanoma, gastric and/or duodenal ulcers, bleeding disorders, or frequent migraines).

Design outcomes

Primary

MeasureTime frameDescription
Targeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) ConnectivityBaseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)Patients will undergo resting-state and task-based functional magnetic resonance imaging (fMRI) to calculate functional connectivity (FC) between the ventral striatum (VS) and ventromedial prefrontal cortex (vmPFC). FC is measured as continuous Z scores reflecting the correlation of activity between the brain regions using Fisher's Z transformation {Z(R)=0.5ln\[(1+R)/(1-R)\]}. This is a standard method for calculating fMRI FC whereby higher FC Z scores reflect stronger connectivity.

Secondary

MeasureTime frameDescription
Effort-Expenditure for Rewards Task (EEfRT)Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)The EEfRT is a widely used, multi-trial task in which participants are given an opportunity on each trial to choose between two different task difficulty levels in order to obtain monetary rewards. EEfRT will be used as an objective measure of motivation and will be administered following MRI scans during the study. The EEfRT is reported as the percent of high effort trials selected. A higher percentage reflects higher motivation for effort expenditure.
Inventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia ScaleBaseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)Anhedonia symptoms experienced over the past 7 days will be assessed from a subscale of the Inventory of Depressive Symptomatology- Self-Report (IDS-SR), a widely used self-report for measuring depression severity. The anhedonia subscale score is created by summing responses to items #8 (responsiveness of mood to good or desired events), #19 (general interest), and #21 (capacity for pleasure). Total anhedonia subscale scores range from 0-9 with higher scores reflecting greater anhedonia.
Hedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)The Snaith-Hamilton Pleasure Scale-Clinician (SHAPS-C) is a clinician-administered version of a validated tool for assessing hedonic tone. The SHAPS-C uses 14 questions. If Strongly disagree or disagree is chosen as the answer, item receives a score of 1 per question. If Strongly agree or agree is chosen, item receives a score of 0; then sum the scores. Total possible score ranges from 0 to 14, with higher scores reflecting greater pathology (worse study outcome).
Motivation and Pleasure-Self-Report (MAP-SR)Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)The Motivation and Pleasure-Self-Report (MAP-SR) will be used to capture self-reported aspects of anhedonia and reduced motivation. The scale uses 18 question each rated on a Likert scale of 0-4. Total possible score ranges from 18 to 72, with higher scores reflecting worse outcome.
Hamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation ItemBaseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)The anhedonia and motivation-related item from the clinician administered Hamilton Depression Rating Scale (HAM-D) (item #7: work and activities) will be used to measure anhedonia. This item is rated on a scale of 0-4 with higher scores reflecting worse outcome.

Countries

United States

Participant flow

Pre-assignment details

38 individuals consented to participate in the study and underwent study-specific screening. 19 of these individuals met eligibility criteria and took part in the study. Only those who actually started the study are included in the following tables.

Participants by arm

ArmCount
Carbidopa Levodopa Followed by Placebo
Participants will receive first Carbidopa Levodopa at doses ranging from 150 to 450 mg administered at a ratio of 1 mg carbidopa for every 4 mg L-DOPA with a starting dose of 150 mg/day with dose escalation 150 mg/day per week to a final dose of 450 mg/day; and then placebo. Carbidopa Levodopa: Patients will receive L-DOPA at doses ranging from 150 to 450 mg administered at a ratio of 1 mg carbidopa for every 4 mg L-DOPA. Starting dose is 150 mg/day with dose escalation 150 mg/day per week to a final dose of 450 mg/day Placebo: A placebo is a sugar pill that has no therapeutic effect and will be administered orally. Participants will receive 1 placebo tablet matching the Carbidopa Levodopa tablet.
10
Placebo Followed by Carbidopa Levodopa
Participants will receive first placebo, and then Carbidopa Levodopa (L-DOPA) at doses ranging from 150 to 450 mg administered at a ratio of 1 mg carbidopa for every 4 mg L-DOPA with a starting dose of 150 mg/day with dose escalation 150 mg/day per week to a final dose of 450 mg/day. Carbidopa Levodopa: Patients will receive L-DOPA at doses ranging from 150 to 450 mg administered at a ratio of 1 mg carbidopa for every 4 mg L-DOPA. Starting dose is 150 mg/day with dose escalation 150 mg/day per week to a final dose of 450 mg/day Placebo: A placebo is a sugar pill that has no therapeutic effect and will be administered orally. Participants will receive 1 placebo tablet matching the Carbidopa Levodopa tablet.
9
Total19

Baseline characteristics

CharacteristicPlacebo Followed by Carbidopa LevodopaTotalCarbidopa Levodopa Followed by Placebo
Age, Continuous39.4 years
STANDARD_DEVIATION 8.6
36.7 years
STANDARD_DEVIATION 9
34.3 years
STANDARD_DEVIATION 9
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
United States
9 participants19 participants10 participants
Sex: Female, Male
Female
7 Participants17 Participants10 Participants
Sex: Female, Male
Male
2 Participants2 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 180 / 180 / 180 / 19
other
Total, other adverse events
12 / 1811 / 1811 / 185 / 19
serious
Total, serious adverse events
0 / 180 / 180 / 180 / 19

Outcome results

Primary

Targeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) Connectivity

Patients will undergo resting-state and task-based functional magnetic resonance imaging (fMRI) to calculate functional connectivity (FC) between the ventral striatum (VS) and ventromedial prefrontal cortex (vmPFC). FC is measured as continuous Z scores reflecting the correlation of activity between the brain regions using Fisher's Z transformation {Z(R)=0.5ln\[(1+R)/(1-R)\]}. This is a standard method for calculating fMRI FC whereby higher FC Z scores reflect stronger connectivity.

Time frame: Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)

Population: Reported sample sizes reflect the number of available and analyzable fMRI scans for each condition from participants having data at baseline and at least one post L-DOPA or post placebo scan

ArmMeasureGroupValue (MEAN)Dispersion
All ParticipantsTargeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) ConnectivityBaseline0.183 Mean subject-level FC Z scoresStandard Deviation 0.132
All ParticipantsTargeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) ConnectivityWeek 1 post- placebo0.219 Mean subject-level FC Z scoresStandard Deviation 0.125
All ParticipantsTargeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) ConnectivityWeek 1 post L-DOPA (150 mg/day)0.275 Mean subject-level FC Z scoresStandard Deviation 0.133
All ParticipantsTargeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) ConnectivityWeek 1 post L-DOPA (300 mg/day)0.202 Mean subject-level FC Z scoresStandard Deviation 0.134
All ParticipantsTargeted Ventral Striatum to Ventromedial Prefrontal Cortex (VS-vmPFC) ConnectivityWeek 1 post L-DOPA (450 mg/day)0.287 Mean subject-level FC Z scoresStandard Deviation 0.135
Secondary

Effort-Expenditure for Rewards Task (EEfRT)

The EEfRT is a widely used, multi-trial task in which participants are given an opportunity on each trial to choose between two different task difficulty levels in order to obtain monetary rewards. EEfRT will be used as an objective measure of motivation and will be administered following MRI scans during the study. The EEfRT is reported as the percent of high effort trials selected. A higher percentage reflects higher motivation for effort expenditure.

Time frame: Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)

Population: Reported sample sizes reflect the number of participants with available EEfRT data for each condition.

ArmMeasureGroupValue (MEAN)Dispersion
All ParticipantsEffort-Expenditure for Rewards Task (EEfRT)Baseline0.369 percentage of choicesStandard Deviation 0.198
All ParticipantsEffort-Expenditure for Rewards Task (EEfRT)Week 1 post-placebo0.300 percentage of choicesStandard Deviation 0.165
All ParticipantsEffort-Expenditure for Rewards Task (EEfRT)Week 1 post L-DOPA (150 mg/day)0.368 percentage of choicesStandard Deviation 0.145
All ParticipantsEffort-Expenditure for Rewards Task (EEfRT)Week 1 post L-DOPA (300 mg/day)0.322 percentage of choicesStandard Deviation 0.153
All ParticipantsEffort-Expenditure for Rewards Task (EEfRT)Week 1 post L-DOPA (450 mg/day)0.330 percentage of choicesStandard Deviation 0.154
Secondary

Hamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation Item

The anhedonia and motivation-related item from the clinician administered Hamilton Depression Rating Scale (HAM-D) (item #7: work and activities) will be used to measure anhedonia. This item is rated on a scale of 0-4 with higher scores reflecting worse outcome.

Time frame: Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)

Population: Lower sample sizes reflect participant withdrawal or incomplete data.

ArmMeasureGroupValue (MEAN)Dispersion
All ParticipantsHamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation ItemBaseline3.0 score on a scaleStandard Deviation 0.3
All ParticipantsHamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation ItemWeek 1 post-placebo1.9 score on a scaleStandard Deviation 1.1
All ParticipantsHamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation ItemWeek 1 post L-DOPA (150 mg/day)1.6 score on a scaleStandard Deviation 1.1
All ParticipantsHamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation ItemWeek 1 post L-DOPA (300 mg/day)1.3 score on a scaleStandard Deviation 0.9
All ParticipantsHamilton Depression Rating Scale (HAM-D) Anhedonia and Motivation ItemWeek 1 post L-DOPA (450 mg/day)1.8 score on a scaleStandard Deviation 1
Secondary

Hedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )

The Snaith-Hamilton Pleasure Scale-Clinician (SHAPS-C) is a clinician-administered version of a validated tool for assessing hedonic tone. The SHAPS-C uses 14 questions. If Strongly disagree or disagree is chosen as the answer, item receives a score of 1 per question. If Strongly agree or agree is chosen, item receives a score of 0; then sum the scores. Total possible score ranges from 0 to 14, with higher scores reflecting greater pathology (worse study outcome).

Time frame: Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)

Population: Smaller sample sizes reflect participant withdrawal or incomplete data

ArmMeasureGroupValue (MEAN)Dispersion
All ParticipantsHedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )Baseline9.7 score on a scaleStandard Deviation 4.1
All ParticipantsHedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )Week 1 post-placebo5.6 score on a scaleStandard Deviation 5.4
All ParticipantsHedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )Week 1 post L-DOPA (150 mg/day)3.9 score on a scaleStandard Deviation 4.3
All ParticipantsHedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )Week 1 post L-DOPA (300 mg/day)4.9 score on a scaleStandard Deviation 5.1
All ParticipantsHedonic Capacity as Measured by the Snaith Hamilton Pleasure Clinician Scale (SHAPS-C )Week 1 post L-DOPA (450 mg/day)5.3 score on a scaleStandard Deviation 5.2
Secondary

Inventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia Scale

Anhedonia symptoms experienced over the past 7 days will be assessed from a subscale of the Inventory of Depressive Symptomatology- Self-Report (IDS-SR), a widely used self-report for measuring depression severity. The anhedonia subscale score is created by summing responses to items #8 (responsiveness of mood to good or desired events), #19 (general interest), and #21 (capacity for pleasure). Total anhedonia subscale scores range from 0-9 with higher scores reflecting greater anhedonia.

Time frame: Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)

Population: Smaller sample sizes reflect participant withdrawal or incomplete data

ArmMeasureGroupValue (MEAN)Dispersion
All ParticipantsInventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia ScaleBaseline5.2 score on a scaleStandard Deviation 2
All ParticipantsInventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia ScaleWeek 1 post-placebo3.0 score on a scaleStandard Deviation 2.1
All ParticipantsInventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia ScaleWeek 1 post L-DOPA (150 mg/day)2.5 score on a scaleStandard Deviation 1.5
All ParticipantsInventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia ScaleWeek 1 post L-DOPA (300 mg/day)2.4 score on a scaleStandard Deviation 1.8
All ParticipantsInventory of Depressive Symptomatology- Self-Report (IDS-SR) Anhedonia ScaleWeek 1 post L-DOPA (450 mg/day)3.2 score on a scaleStandard Deviation 1.7
Secondary

Motivation and Pleasure-Self-Report (MAP-SR)

The Motivation and Pleasure-Self-Report (MAP-SR) will be used to capture self-reported aspects of anhedonia and reduced motivation. The scale uses 18 question each rated on a Likert scale of 0-4. Total possible score ranges from 18 to 72, with higher scores reflecting worse outcome.

Time frame: Baseline, 1-week of placebo, and 1-week at each dose of L-DOPA (150 mg/day, 300 mg/day and 450 mg/day)

Population: Smaller sample sizes reflect participant withdrawal or incomplete data.

ArmMeasureGroupValue (MEAN)Dispersion
All ParticipantsMotivation and Pleasure-Self-Report (MAP-SR)Baseline22.4 mean MAP-SR total scoreStandard Deviation 9.9
All ParticipantsMotivation and Pleasure-Self-Report (MAP-SR)Week 1 post-placebo35.0 mean MAP-SR total scoreStandard Deviation 13.4
All ParticipantsMotivation and Pleasure-Self-Report (MAP-SR)Week 1 post L-DOPA (150 mg/day)35.4 mean MAP-SR total scoreStandard Deviation 7
All ParticipantsMotivation and Pleasure-Self-Report (MAP-SR)Week 1 post L-DOPA (300 mg/day)35.3 mean MAP-SR total scoreStandard Deviation 5.2
All ParticipantsMotivation and Pleasure-Self-Report (MAP-SR)Week 1 post L-DOPA (450 mg/day)33.5 mean MAP-SR total scoreStandard Deviation 8

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026