A Phase 2 interventional study of Dextroamphetamine and Placebo in Schizophrenia, sponsored by University of California, San Diego. Completed at 1 site in United States. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2021-08-17.
Sponsored by University of California, San Diego · Phase 2, Interventional, and Treatment
This application seeks renewed support for MH59803, "Dopaminergic substrates of startle gating across species," to extend a clear path of "bench-to-bedside" progress towards a critical paradigm shift in therapeutic models for schizophrenia (SZ) and schizoaffective disorder, depressed type (SZA): the use of Pharmacologic Augmentation of Cognitive Therapies (PACTs). This novel therapeutic strategy for SZ/SZA directly addresses the need for more effective treatments for this devastating disorder. MH59803 has investigated the neural regulation of laboratory-based measures of deficient information processing in SZ/SZA patients, using rodents and healthy human subjects (HS) to explicate the biology of these deficits, and to establish a rational basis for developing novel therapies for SZ/SZA. In its first 9 years, MH59803 studies of the neural regulation of prepulse inhibition (PPI) of startle in rats focused on basic neurobiological and molecular mechanisms. Over the past 2 years of support, MH59803 studies moved "from bench-to-bedside," focusing on dopamine (DA) agonist effects on PPI and neurocognition in HS, and their regulation by genes identified in cross-species studies. These studies detected biological markers that predict PPI-enhancing and pro-cognitive effects of the DA releaser, amphetamine (AMPH) in humans, leading to specific predictions of AMPH effects on PPI, neurocognition and Targeted Cognitive Training in SZ/SZA patients. If confirmed in the present application, these predictions could help transform therapeutic approaches to SZ/SZA. This renewal application of MH59803 thus reflects a logical progression of studies at systems and molecular levels, translated first to HS, and now to potentially transformative therapeutic models in SZ/SZA patients.
MH59803 demonstrated that AMPH (20 mg p.o.) significantly increased PPI and neurocognitive performance (MATRICS Consensus Cognitive Battery; MCCB) in HS characterized by specific performance-based or genetic biomarkers, including the val/val genotype for the rs4680 polymorphism of catechol-O-methyltransferase (COMT). Mechanistically-informative results were detected in studies of AMPH effects on PPI in rats with high vs. low brain regional Comt expression. Together with several reports of improved neurocognition and no adverse effects of acute or sustained AMPH administration to antipsychotic (AP)-medicated SZ/SZA patients, MH59803 findings provide a strong rationale for the next goal of this application: to test the potential utility of AMPH in a paradigm of biomarker-informed "PACTs". This "next step" is highly innovative - never previously reported, or perhaps even attempted - and consistent with National Institute of Mental Health (NIMH) objectives, directly challenges existing models for SZ/SZA therapeutics. Investigators will determine whether a test dose of 10 mg AMPH p.o. administered to biomarker-identified, AP-medicated SZ/SZA patients generates predicted increases in PPI, MCCB performance, and sensory discrimination learning in a Targeted Cognitive Training (TCT) module. In total, Investigators will leverage knowledge generated through converging cross-species studies in MH59803, to directly advance scientific and clinical domains, by testing the effects of a pro-cognitive drug on neurophysiological and neurocognitive performance, and Targeted Cognitive Training, in biomarker-stratified subgroups of SZ/SZA patients.
Aim: To assess acute effects of AMPH (0 vs 10 mg po) on PPI, neurocognition and computerized TCT in AP-medicated SZ/SZA patients. Hypothesis: PPI- and MCCB-enhancing effects of AMPH seen previously in HS will also be detected in SZ/SZA patients, as will TCT-enhancing effects of AMPH. Prediction: In a within-subject, placebo-controlled, randomized design, AMPH (10 mg po) will increase PPI and enhance MCCB and TCT performance in medicated SZ/SZA patients, particularly among those characterized by low basal performance levels and/or the val/val rs4680 COMT polymorphism. Concurrent HS testing will confirm and extend findings of AMPH effects on PPI and neurocognition, and help interpret findings in SZ/SZA patients.
In all participants, the aim to assess acute effects of 0 vs. 10 mg po dextroamphetamine (AMPH) on Prepulse Inhibition (PPI), neurocognition MATRICS: Consensus Cognitive Battery; MCCB, and computerized Targeted Cognitive Training (TCT).
Hypothesis: AMPH will enhance:
Prediction: In a within-subject, placebo-controlled, randomized design, AMPH (10 mg po) will increase PPI and enhance MCCB and TCT performance in medicated SZ/SZA patients, particularly among those characterized by low basal performance levels and/or the val/val rs4680 COMT polymorphism. Concurrent HS testing will confirm and extend findings of AMPH effects on PPI and neurocognition, and help interpret findings in SZ/SZA patients.
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Drug: Dexedrine, dextroamphetamine, d-amphetamine. Dosage form, frequency and duration: Each participant receives a single pill of placebo or active drug (dextroamphetamine 10 mg) 30 minutes after arriving at the lab. The participant then completes approximately 6 hours of testing in the laboratory. The participant stays at the lab for 7.5 hours in order to monitor physical condition in case the participant received the active pill One week later, that participant receives a single pill of the alternate comparator and is again tested in the laboratory. Thus, in total, each participant receives one placebo pill and one active pill, separated by one week.
Drug: Dextroamphetamine · Drug: Placebo
Drug: Dexedrine, dextroamphetamine, d-amphetamine Dosage form, frequency and duration: Each participant receives a single pill of placebo or active drug (dextroamphetamine 10 mg) 30 minutes after arriving at the lab. The participant then completes approximately 6 hours of testing in the laboratory. The participant stays at the lab for 7.5 hours in order to monitor physical condition in case the participant received the active pill One week later, that participant receives a single pill of the alternate comparator and is again tested in the laboratory. Thus, in total, each participant receives one placebo pill and one active pill, separated by one week.
Drug: Dextroamphetamine · Drug: Placebo
Each participant receives a single pill of placebo or active drug (dextroamphetamine 10 mg) and completes approximately 6 hours of testing in the laboratory. One week later, that participant receives a single pill of the alternate comparator and is again tested in the laboratory. Thus, in total, each participant receives one placebo pill and one active pill, separated by one week.
Also known as: d-amphetamine, Dexedrine
Each participant receives a single pill of placebo or active drug (dextroamphetamine 10 mg) and completes approximately 6 hours of testing in the laboratory. One week later, that participant receives a single pill of the alternate comparator and is again tested in the laboratory. Thus, in total, each participant receives one placebo pill and one active pill, separated by one week.
Prepulse Inhibition (PPI)
PPI was assessed with 42 trials of 6 types: 118 dB 40 ms pulse alone (P) \& the same P preceded 10, 20, 30, 60, or 120 ms by a prepulse (pp) 16 dB over background. Startle magnitude (SM), habituation, latency \& latency facilitation were measured to interpret changes in PPI. %PPI = 100 x \[(SM on P trials) - (SM on pp+P trials)\] / SM on P trials. Example: SM on P trials = 80 units SM on pp+P trials = 30 units %PPI = 100 x (80-30)/80 = 100 x 50/80 = 62.5% Greater %PPI mean the reflex has been inhibited to a greater extent in the presence of a pp. %PPI can't exceed 100: when SM on pp+P trials = 0, then %PPI = 100 x (SM on P trials - 0)/SM on P trials = 100 x 1 = 100%. However, %PPI can theoretically be infinitely negative since SM on pp+P trials could be infinitely large ("prepulse facilitiation" (PPF)), i.e. SM is potentiated in the presence of a pp. PPF is "normal" at very short \& very long pp intervals, but not within a species-specific physiological range of intervals.
Time frame: two visits, 1 week apart, each visit lasting approximately 6 hours
MATRICS Consensus Cognitive Battery Performance (MCCB)
The T-score indicates the performance on a neurocognitive battery of tests. Higher score reflects better performance.
Time frame: two visits, 1 week apart, each visit lasting approximately 6 hours
Targeted Cognitive Training (TCT): PositScience, Inc.
Auditory discrimination learning: Subjects identify direction (up vs. down) of 2 consecutive sound sweeps. Parameters (e.g. inter-sweep interval, sweep duration) are established for subjects to maintain 80% correct responses. On screen and test days, subjects complete 1h of TCT. Analytic software yields the key measures: auditory processing speed (APS) and APS "learning". APS is the shortest inter-stimulus interval at which a subject performs to criteria and APS learning is the difference (ms) between the first APS and the best APS of the subsequent trials. A smaller APS reflects "better" discrimination (i.e., subject correctly identified frequency "sweep" direction despite a smaller ms gap between stimuli) and a larger ms value for APS learning reflects more learning, i.e., faster APS with repeated trials. Limits for APS are capped at 0-to-1000 ms; values for APS learning are capped at (-) 1000-to-APS.
Time frame: two visits, 1 week apart, each visit lasting approximately 6 hours
| Milestone | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo |
|---|---|---|---|---|
| Started | 19 | 19 | 21 | 23 |
| Completed | 19 | 19 | 21 | 23 |
| Not completed | 0 | 0 | 0 | 0 |
PPI was assessed with 42 trials of 6 types: 118 dB 40 ms pulse alone (P) \& the same P preceded 10, 20, 30, 60, or 120 ms by a prepulse (pp) 16 dB over background. Startle magnitude (SM), habituation, latency \& latency facilitation were measured to interpret changes in PPI. %PPI = 100 x \[(SM on P trials) - (SM on pp+P trials)\] / SM on P trials. Example: SM on P trials = 80 units SM on pp+P trials = 30 units %PPI = 100 x (80-30)/80 = 100 x 50/80 = 62.5% Greater %PPI mean the reflex has been inhibited to a greater extent in the presence of a pp. %PPI can't exceed 100: when SM on pp+P trials = 0, then %PPI = 100 x (SM on P trials - 0)/SM on P trials = 100 x 1 = 100%. However, %PPI can theoretically be infinitely negative since SM on pp+P trials could be infinitely large ("prepulse facilitiation" (PPF)), i.e. SM is potentiated in the presence of a pp. PPF is "normal" at very short \& very long pp intervals, but not within a species-specific physiological range of intervals.
| % inhibition of startle | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo |
|---|---|---|---|---|
| Placebo | 22.629 ± 62.657 | 41.162 ± 42.103 | 50.626 ± 25.850 | 50.626 ± 29.621 |
| Amphetamine | 32.656 ± 57.669 | 39.545 ± 33.429 | 45.822 ± 31.777 | 53.029 ± 24.671 |
The T-score indicates the performance on a neurocognitive battery of tests. Higher score reflects better performance.
| standardized T-score | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo |
|---|---|---|---|---|
| placebo | 31.895 ± 15.937 | 39.895 ± 11.704 | 54.476 ± 11.557 | 57.870 ± 11.153 |
| amphetamine | 33.842 ± 16.269 | 38.105 ± 12.552 | 55.476 ± 11.383 | 56.000 ± 11.286 |
Auditory discrimination learning: Subjects identify direction (up vs. down) of 2 consecutive sound sweeps. Parameters (e.g. inter-sweep interval, sweep duration) are established for subjects to maintain 80% correct responses. On screen and test days, subjects complete 1h of TCT. Analytic software yields the key measures: auditory processing speed (APS) and APS "learning". APS is the shortest inter-stimulus interval at which a subject performs to criteria and APS learning is the difference (ms) between the first APS and the best APS of the subsequent trials. A smaller APS reflects "better" discrimination (i.e., subject correctly identified frequency "sweep" direction despite a smaller ms gap between stimuli) and a larger ms value for APS learning reflects more learning, i.e., faster APS with repeated trials. Limits for APS are capped at 0-to-1000 ms; values for APS learning are capped at (-) 1000-to-APS.
| msec | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo |
|---|---|---|---|---|
| placebo | -15.118 ± 346.088 | -50.158 ± 218.464 | 5.911 ± 75.105 | -2.113 ± 107.563 |
| amphetamine | 52.647 ± 305.887 | 101.000 ± 434.379 | 35.905 ± 64.539 | 29.190 ± 83.183 |
Collected over two visits, 1 week apart, each visit lasting approximately 6 hours. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Subjects With Schizophrenia: Placebo | 0/38 (0%) | 0/38 (0%) | 0/38 (0%) |
| Subjects With Schizophrenia: 10 mg Amphetamine | 0/38 (0%) | 0/38 (0%) | 0/38 (0%) |
| Healthy Subjects: Placebo | 0/44 (0%) | 0/44 (0%) | 0/44 (0%) |
| Healthy Subjects: 10 mg Amphetamine | 0/44 (0%) | 0/44 (0%) | 0/44 (0%) |
| Age, Continuous(years) | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo | Total |
|---|---|---|---|---|---|
| Mean | 39 (23 to 51) | 42 (27 to 55) | 29 (19 to 55) | 30 (20 to 53) | 35 (19 to 55) |
| Sex: Female, Male(Participants) | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo | Total |
|---|---|---|---|---|---|
| Female | 11 | 6 | 6 | 6 | 29 |
| Male | 8 | 13 | 15 | 17 | 53 |
| Ethnicity (NIH/OMB)(Participants) | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo | Total |
|---|---|---|---|---|---|
| Hispanic or Latino | 5 | 8 | 6 | 5 | 24 |
| Not Hispanic or Latino | 12 | 9 | 13 | 18 | 52 |
| Unknown or Not Reported | 2 | 2 | 2 | 0 | 6 |
| Race (NIH/OMB)(Participants) | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo | Total |
|---|---|---|---|---|---|
| American Indian or Alaska Native | 3 | 3 | 2 | 4 | 12 |
| Asian | 0 | 2 | 5 | 6 | 13 |
| Native Hawaiian or Other Pacific Islander | 0 | 1 | 0 | 0 | 1 |
| Black or African American | 8 | 3 | 3 | 1 | 15 |
| White | 5 | 7 | 7 | 12 | 31 |
| More than one race | 2 | 2 | 1 | 0 | 5 |
| Unknown or Not Reported | 1 | 1 | 3 | 0 | 5 |
| Region of Enrollment(participants) | Subjects With Schizophrenia: Placebo 1st, Then 10 mg Amphetamine | Subjects With Schizophrenia: 10 mg Amphetamine 1st, Then Placebo | Healthy Subjects: Placebo 1st, Then 10 mg Amphetamine | Healthy Subjects: 10 mg Amphetamine 1st, Then Placebo | Total |
|---|---|---|---|---|---|
| United States | 19 | 19 | 21 | 23 | 82 |
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University of California, San Diego