Adults 18 to 65, any sex, with Major Depressive Disorder. 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.
Change From Double-blind Baseline in Montgomery-Asberg Depression Rating Scale (MADRS) - Total Score at Week 14Primary· Week 8 (double-blind baseline ) and week 14 (week 6 of double-blind phase)
MADRS measures the overall severity of depressive symptoms. The MADRS had a 10-item checklist. Items are rated on a scale of 0-6, for a total numeric range of scores from 0 (depressive symptoms absent) to 60 (numerically highest level of depressive symptoms).
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
29.5
± 6.00
Placebo + ADT
29.1
± 5.54
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-10.3
± 8.60
Placebo + ADT
-8.8
± 10.40
Change From Double-blind Baseline in Montgomery-Asberg Depression Rating Scale (MADRS) - Total Score at Weeks 9 Through 13Secondary· Week 8 (double-blind baseline) and weeks 9 through 13
MADRS measures the overall severity of depressive symptoms. The MADRS had a 10-item checklist. Items are rated on a scale of 0-6, for a total numeric range of scores from 0 (depressive symptoms absent) to 60 (numerically highest level of depressive symptoms).
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
29.5
± 6.00
Placebo + ADT
29.1
± 5.54
Change at Week 9
Group
Value
95% CI
CP-601,927 + ADT
-2.4
± 4.68
Placebo + ADT
-3.3
± 5.35
Change at Week 10
Group
Value
95% CI
CP-601,927 + ADT
-4.7
± 6.65
Placebo + ADT
-4.6
± 6.85
Change at Week 11
Group
Value
95% CI
CP-601,927 + ADT
-7.0
± 7.78
Placebo + ADT
-6.0
± 8.06
Change at Week 12
Group
Value
95% CI
CP-601,927 + ADT
-8.5
± 8.08
Placebo + ADT
-7.4
± 8.83
Change at week 13
Group
Value
95% CI
CP-601,927 + ADT
-8.6
± 8.16
Placebo + ADT
-7.9
± 9.37
Change From Double-blind Baseline in Hamilton Depression Scale 25-item (HAM-D25) - Total Score at Weeks 9 Through 14Secondary· Weeks 8 (double-blind baseline) through 14
The HAM-D25 is the 25-item version of a scale used to assess the range of depressive symptoms including depressed mood, work and activities, sleep, suicidal thinking, psychomotor agitation/retardation, appetite, sexual interest, anxiety, somatic symptoms, and cognitive symptoms. The items on the HAM-D were rated on a scale of 0-2 or 0-4, for a total numeric range of scores from 0 (depressive symptoms absent) to 72 (numerically highest level of depressive symptoms).
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
26.4
± 4.25
Placebo + ADT
26.3
± 4.96
Change at week 9
Group
Value
95% CI
CP-601,927 + ADT
-3.0
± 4.49
Placebo + ADT
-3.0
± 5.25
Change at week 10
Group
Value
95% CI
CP-601,927 + ADT
-4.4
± 6.57
Placebo + ADT
-4.7
± 5.78
Change at week 11
Group
Value
95% CI
CP-601,927 + ADT
-5.9
± 7.40
Placebo + ADT
-6.4
± 7.06
Change at week 12
Group
Value
95% CI
CP-601,927 + ADT
-7.6
± 7.63
Placebo + ADT
-6.7
± 7.67
Change at week 13
Group
Value
95% CI
CP-601,927 + ADT
-8.0
± 7.22
Placebo + ADT
-7.3
± 7.90
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-9.1
± 7.76
Placebo + ADT
-8.4
± 8.99
Change From Double-blind Baseline in Bech Melancholia Subscale Score at Weeks 9 Through 14Secondary· Weeks 8 (double-blind baseline) through 14
The Bech Melancholia is sum of scores on 6 items (items 1, 2, 7, 8, 10 and 13) pertaining to melancholia within HAM-D. The items are rated on a scale of 0-4, higher scores reflecting greater severity. Total possible score is 0-24.
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
11.6
± 1.90
Placebo + ADT
11.6
± 2.05
Change at week 9
Group
Value
95% CI
CP-601,927 + ADT
-1.3
± 2.31
Placebo + ADT
-1.5
± 2.48
Change at week 10
Group
Value
95% CI
CP-601,927 + ADT
-2.1
± 3.07
Placebo + ADT
-2.0
± 2.87
Change at week 11
Group
Value
95% CI
CP-601,927 + ADT
-3.0
± 3.55
Placebo + ADT
-2.7
± 3.38
Change at week 12
Group
Value
95% CI
CP-601,927 + ADT
-3.6
± 3.65
Placebo + ADT
-3.0
± 3.40
Change at week 13
Group
Value
95% CI
CP-601,927 + ADT
-3.8
± 3.56
Placebo + ADT
-3.2
± 3.69
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-4.3
± 3.87
Placebo + ADT
-3.7
± 4.15
Change From Double-blind Baseline in Clinical Global Impression - Severity (CGI-S) at Weeks 9, 10, 12, and 14Secondary· Week 8 (double-blind baseline) and weeks 9, 10, 12, 14
CGI-S was defined as 7-point clinician rated scale to assess severity of participant's current illness state; range: 1 (normal - not ill at all) to 7 (among the most extremely ill participants). Higher score = more affected.
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
4.2
± 0.59
Placebo + ADT
4.2
± 0.67
Change at week 9
Group
Value
95% CI
CP-601,927 + ADT
-0.2
± 0.49
Placebo + ADT
-0.2
± 0.60
Change at week 10
Group
Value
95% CI
CP-601,927 + ADT
-0.5
± 0.81
Placebo + ADT
-0.5
± 0.83
Change at week 12
Group
Value
95% CI
CP-601,927 + ADT
-0.8
± 1.01
Placebo + ADT
-0.7
± 1.14
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-1.1
± 1.11
Placebo + ADT
-1.0
± 1.18
Change From Double-blind Baseline in Sheehan Irritability Scale (SIS) Total Score at Weeks 11 and 14Secondary· Weeks 8 (double-blind baseline), 11 and 14
The SIS is to rate suffering with regard to irritability symptoms. The degree to which irritability interferes with work, social and family function is also queried. The total SIS score is the sum of 7 items. Each item is rated on a scale of 0-10, for a total numeric range of scores from 0 (not at all) to 70 (extremely). The SIS also records the number of days impaired by irritability.
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
36.1
± 13.21
Placebo + ADT
34.8
± 13.68
Change at week 11
Group
Value
95% CI
CP-601,927 + ADT
-9.3
± 14.41
Placebo + ADT
-7.3
± 13.70
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-12.3
± 15.80
Placebo + ADT
-10.4
± 17.11
Change From Double-blind Baseline in Sheehan Disability Scale (SDS) Total Score at Weeks 11 and 14Secondary· Weeks 8 (double-blind baseline), 11 and 14
SDS is defined as a self-administered tool that measures functional impairment including work/school, social life, and family life/home responsibilities. Items are rated on a scale of 0-10 visual analog scale (0=not at all impaired, 10=extremely impaired), for a total numeric range of scores from 0 (not at all impaired) to 30 (extremely impaired).
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
19.0
± 5.88
Placebo + ADT
18.5
± 5.30
Change at week 11
Group
Value
95% CI
CP-601,927 + ADT
-5.6
± 6.98
Placebo + ADT
-3.8
± 6.33
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-6.6
± 7.98
Placebo + ADT
-5.7
± 8.21
Change From Double-blind Baseline in Sheehan Disability Scale (SDS) Subscale Score at Weeks 11 and 14Secondary· Weeks 8 (double-blind baseline), 11 and 14
SDS subscale is defined as a self-administered tool that measures functional impairment in 3-item including work/school, social life, and family life/home responsibilities. Items are rated on a scale of 0-10 visual analog scale, for a total numeric range of scores from 0 (not at all impaired) to 30 (extremely impaired).
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
6.0
± 2.22
Placebo + ADT
5.5
± 2.66
Change at week 11
Group
Value
95% CI
CP-601,927 + ADT
-2.1
± 2.86
Placebo + ADT
-0.9
± 2.10
Change at week 14
Group
Value
95% CI
CP-601,927 + ADT
-2.1
± 2.88
Placebo + ADT
-1.9
± 2.66
Clinical Global Impression - Improvement (CGI-I) Total Score at Weeks 9, 10, 12 and 14Secondary· Weeks 8 (double-blind baseline) 9, 10, 12 and 14
CGI-I was defined as a 7-point clinician rated scale ranging from 1 (very much improved) to 7 (very much worse). Improvement was defined as a score of 1 (very much improved), 2 (much improved), or 3 (minimally improved) on the scale. Higher score = more affected.
Week 8 (double-blind baseline)
Group
Value
95% CI
CP-601,927 + ADT
3.7
± 0.77
Placebo + ADT
3.5
± 0.66
Week 9
Group
Value
95% CI
CP-601,927 + ADT
3.4
± 0.84
Placebo + ADT
3.2
± 0.78
Week 10
Group
Value
95% CI
CP-601,927 + ADT
3.2
± 0.92
Placebo + ADT
3.1
± 0.88
Week 12
Group
Value
95% CI
CP-601,927 + ADT
2.7
± 1.05
Placebo + ADT
2.8
± 1.07
Week 14
Group
Value
95% CI
CP-601,927 + ADT
2.5
± 1.05
Placebo + ADT
2.7
± 1.03
Number of Participants With Remission at Weeks 9, 10, 12 and 14Secondary· Weeks 9, 10, 12 and 14
Remission was defined as response plus an absolute MADRS total score of less than or equal to 10 plus a CGI-I score less than 2 ('much' or 'very much' improved).
Week 9
Group
Value
95% CI
CP-601,927 + ADT
1
Placebo + ADT
0
Week 10
Group
Value
95% CI
CP-601,927 + ADT
4
Placebo + ADT
1
Week 12
Group
Value
95% CI
CP-601,927 + ADT
5
Placebo + ADT
9
Week 14
Group
Value
95% CI
CP-601,927 + ADT
9
Placebo + ADT
11
Number of Participants With Response at Weeks 9 Through 14Secondary· Weeks 9 through 14
Response was defined as greater than 50 percent reduction from double-blind baseline in MADRS total score.
Week 9
Group
Value
95% CI
CP-601,927 + ADT
3
Placebo + ADT
4
Week 10
Group
Value
95% CI
CP-601,927 + ADT
8
Placebo + ADT
8
Week 11
Group
Value
95% CI
CP-601,927 + ADT
15
Placebo + ADT
10
Week 12
Group
Value
95% CI
CP-601,927 + ADT
18
Placebo + ADT
16
Week 13
Group
Value
95% CI
CP-601,927 + ADT
23
Placebo + ADT
20
Week 14
Group
Value
95% CI
CP-601,927 + ADT
22
Placebo + ADT
20
Plasma CP-601,927 ConcentrationSecondary· Week 11, 12 and 14
Blood samples were collected for plasma CP-601,927 concentration analysis which was summarized by mean and standard deviation.
Week 11 at 1 Hour
Group
Value
95% CI
CP-601,927 + ADT
5.80
± 3.42
Week 11 at 2 Hours
Group
Value
95% CI
CP-601,927 + ADT
5.90
± 3.13
Week 12
Group
Value
95% CI
CP-601,927 + ADT
6.24
± 3.85
Week 14 at 1 Hour
Group
Value
95% CI
CP-601,927 + ADT
5.36
± 3.83
Week 14 at 2 Hour
Group
Value
95% CI
CP-601,927 + ADT
5.39
± 3.89
Adverse events — posted to ClinicalTrials.gov
Reporting threshold: 0%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
Open-Label ADT
Serious: 3/297 (1%)
Deaths: —
CP-601,927 + ADT
Serious: 1/77 (1%)
Deaths: —
Placebo + ADT
Serious: 1/85 (1%)
Deaths: —
Serious adverse events (6 terms)
Reaction
System
Open-Label ADT
CP-601,927 + ADT
Placebo + ADT
Thyroid cancer
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
—
—
—
Suicide attempt
Psychiatric disorders
—
—
—
Atrial fibrillation
Cardiac disorders
—
—
—
Pneumonia
Infections and infestations
—
—
—
Pregnancy
Pregnancy, puerperium and perinatal conditions
—
—
—
Suicidal ideation
Psychiatric disorders
—
—
—
Other adverse events (217 terms — click to expand)
The primary objectives of this study are to: 1) Evaluate the efficacy of CP 601,927 compared to placebo in the augmentation of antidepressant therapy (ADT) in patients with Major Depressive Disorder (MDD) using the Montgomery Asberg Depression Rating Scale (MADRS). 2) Evaluate the safety and tolerability of CP 601,927 in patients with MDD on ADT.
Publications & conference data
1 peer-reviewed publication reference this trial (live from Europe PMC):
NCT01396135 — A Phase 1 Study To Investigate The Pharmacokinetics, Safety And Tolerability Of CP-601,927 In Healthy Japanese Subjects
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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 Pfizer
Last refreshed: 3 May 2021
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/NCT01098240.