Adults 18 to 65, any sex, with Akathisia, Drug-Induced or Antipsychotic Agents. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Part 1: Number of Participants With AkathisiaPrimary· Up to 13 days
Incidence of akathisia is reported as the number of participants who experienced akathisia. Akathisia is defined as a score of 3 on the Barnes akathisia scale (BAS) for 3 consecutive intervals or an akathisia score (BAS) of ≥4 for any single day, or the use of a rescue medication within 13 days of initiating treatment with haloperidol and preladenant. The BAS is scored as follows: objective akathisia, subjective awareness of restlessness and subjective distress related to restlessness are rated on a 4-point scale from 0 - 3 and are summed yielding a total score ranging from 0 (no akathisia) to
Group
Value
95% CI
Part 1: Preladenant
0
Part 1: Placebo
0
Part 2: Number of Participants Who Were Treatment FailuresPrimary· Up to 14 days
Incidence of treatment failure is reported as the number of participants who were treatment failures. A treatment failure is defined as the failure to achieve at least a 1 point reduction from baseline in BAS score at 24 to 26 hours following study treatment. The BAS is scored as follows: objective akathisia, subjective awareness of restlessness and subjective distress related to restlessness are rated on a 4-point scale from 0 - 3 and are summed yielding a total score ranging from 0 (no akathisia) to 9 (severe akathisia).
Group
Value
95% CI
Part 2: Preladenant
4
Part 2: Standard of Care
1
Part 1: Mean Global Clinical Impression at Day 14Secondary· Day 14 of Part 1
Global clinical impression (GCI) was administered to assess whether any deterioration is due to akathisia or uncontrolled psychoses. Score on a scale +2 to -2 (+2 represents much improvement, +1 some improvement, 0 no change, -1 some worsening, and -2 much worsening).
Group
Value
95% CI
Part 1: Preladenant
0.9231
± 0.7596
Part 1: Placebo
1.7778
± 0.4410
Part 1: Mean Positive and Negative Symptom Scale for Schizophrenia (PANSS) Total Score at Day 14Secondary· Day 14 of Part 1
The PANSS is a 30-item clinician-rated instrument for assessing the symptoms of schizophrenia. It consists of 3 subscales: positive subscale (7 items), negative subscale (7 items), and general psychopathology subscale (16 items). Positive symptoms refer to an excess or distortion of normal mental status (e.g., delusions). Negative symptoms represent a diminution or loss of normal functions (e.g., emotional withdrawal).
For each item, symptom severity was rated on a 7-point scale, from 0=absent to 6=extreme. The PANSS total score for each participant was calculated as the sum of the rating ass
Group
Value
95% CI
Part 1: Preladenant
38.4615
± 19.4834
Part 1: Placebo
36.3333
± 17.0587
Part 2: Mean GCI at Day 14Secondary· Day 14 of Part 2
The GCI was administered to assess whether any deterioration is due to akathisia or uncontrolled psychoses. Score on a scale +2 to -2 (+2 represents much improvement, +1 some improvement, 0 no change, -1 some worsening, and -2 much worsening).
Group
Value
95% CI
Part 2: Preladenant
0.6667
± 1.0328
Part 2: Standard of Care
2.0000
± 0.0000
Part 2: PANSS Total Score at Day 14Secondary· Day 14 of Part 2
The PANSS is a 30-item clinician-rated instrument for assessing the symptoms of schizophrenia. It consists of 3 subscales: positive subscale (7 items), negative subscale (7 items), and general psychopathology subscale (16 items). Positive symptoms refer to an excess or distortion of normal mental status (e.g., delusions). Negative symptoms represent a diminution or loss of normal functions (e.g., emotional withdrawal). For each item, symptom severity was rated on a 7-point scale, from 0=absent to 6=extreme. The PANSS total score for each participant was calculated as the sum of the rating assi
Group
Value
95% CI
Part 2: Preladenant
43.5000
± 28.5430
Part 2: Standard of Care
27.75
± 11.2361
Adverse events — posted to ClinicalTrials.gov
Time frame: Up to 22 days (including follow-up).
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
This study is designed to evaluate the effectiveness of preladenant in the prevention (Part 1) or treatment (Part 2) of antipsychotic induced akathisia in participants with acute psychosis using the Barnes Akathisia Scale.
Publications & conference data
1 peer-reviewed publication reference this trial (live from Europe PMC):
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Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Merck Sharp & Dohme LLC
Last refreshed: 7 November 2018
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT00693472.