Icalcaprant / Placebo for Icalcaprant / Bipolar I Disorder · Phase 2 Trial

A Study to Assess Adverse Events and Change in Disease Activity of Oral Icalcaprant in Adult Participants With Bipolar I or II Disorder

ClinicalTrials.gov · August 14, 2026

Preliminary Why this matters to you Expert discussion

Early or partial results. Treat as a signal, not a conclusion.

AI Summary

This is an active Phase 2 registration for icalcaprant, an investigational small-molecule drug, in adults with bipolar I or II disorder. The trial measures depression severity by MADRS change at week 6 and adverse events through week 10. No results are posted; this record describes the study design and planned outcomes only.

What was studied

Phase 2, Interventional, Randomized, Parallel, Quadruple masking, Treatment purpose. Bipolar I Disorder, Bipolar II Disorder; age from 18 Years; to 65 Years. Intervention: Group 1: Icalcaprant Dose A; Group 2: Icalcaprant Dose B. Compared with: Group 3: Placebo for Icalcaprant — Placebo Comparator. n = 195. 33 sites: United States.

Key findings

Safety

This is a registry record; no efficacy or safety results are reported.

Who this may help

Clinicians and researchers should note this ongoing trial as an early-stage evaluation of a novel mechanism for bipolar depression. Results when published will clarify whether icalcaprant meets Phase 2 efficacy and safety thresholds to warrant Phase 3 development.

Plain-language summary

Phase 2 trial of an investigational agent for bipolar depression with surrogate mood and safety endpoints; study is actively recruiting with no results posted.

Study design

As stated by the source record.

MethodsPrimary outcome measures: Change from Baseline to Week 6 in the MADRS (Montgomery-Åsberg Depression Rating Scale) total score (assessed at Up to approximately Week 6); Number of Participants with Adverse Events (AEs) (assessed at Up to approximately 10 weeks)

DesignPhase 2, Interventional, Randomized, Parallel, Quadruple masking, Treatment purpose

PopulationBipolar I Disorder, Bipolar II Disorder; age from 18 Years; to 65 Years

Sample size195

InterventionGroup 1: Icalcaprant Dose A; Group 2: Icalcaprant Dose B

ComparatorGroup 3: Placebo for Icalcaprant — Placebo Comparator

Setting33 sites: United States

Reported figures

Quoted from the source exactly as published.

Planned enrollment195

Phase2

Number of treatment arms3

Randomization probability to placebo1 in 3

Primary outcome measure 1Change from Baseline to Week 6 in MADRS total score

Primary outcome measure 2Number of Participants with Adverse Events, up to approximately 10 weeks

Planned number of study sitesapproximately 35

Study duration of treatment6 weeks

Clinical bottom line

Caveats

This is a registry record; no efficacy or safety results are reported.
The trial is still actively recruiting; no data are available for analysis.
Phase 2 design and sample size (estimated 65 per arm) are insufficient to establish clinical benefit or practice guidance.
Specific inclusion and exclusion criteria, dosing details, and blinding method are not detailed in this registry summary.

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

moderate

Phase 2 RCT with placebo control and 1:1:1 randomization across three arms.

Directness

moderate

MADRS is a validated surrogate for depressive symptom severity; safety endpoints are direct.

Consistency

insufficient

No prior published efficacy data on icalcaprant in bipolar disorder reported in this registry.

Risk of bias

moderate

Placebo-controlled design and randomization reduce bias; no details on blinding or allocation concealment.

Sample adequacy

limited

Estimated 195 participants across three arms (~65 per arm) for Phase 2; underpowered for definitive efficacy.

What is missing. This record has no key findings. That is a gap in the analysis, not a judgement about the study.

Source abstract

Registry record from ClinicalTrials.gov (NCT06696755). This is a study registration, not published results. Lead sponsor: AbbVie. Recruitment status: RECRUITING. Phase: PHASE2. Study type: INTERVENTIONAL. Enrollment: 195 participants (ESTIMATED). Conditions: Bipolar I Disorder, Bipolar II Disorder. Interventions: DRUG: Icalcaprant; DRUG: Placebo for Icalcaprant. Primary outcome measures: Change from Baseline to Week 6 in the MADRS (Montgomery-Åsberg Depression Rating Scale) total score , Up to approximately Week 6; Number of Participants with Adverse Events (AEs) , Up to approximately 10 weeks. Brief summary: Bipolar disorder is a severe chronic mood disorder that affects up to 4% of the adult population and 1.8% of the pediatric population in the United States. This study will assess how safe and effective Icalcaprant is in treating adult participants with bipolar I or II disorder. Icalcaprant is an investigational drug being developed for the treatment of depressive episodes in adult participants with bipolar I or II disorder. Participants are placed in 1 of 3 groups, called treatment arms. There is a 1 in 3 chance that a participant will be assigned to a placebo. Around 195 adult participants with bipolar I or II disorder will be enrolled in approximately 35 sites across the United States of America. Participants will receive oral capsules of Icalcaprant or matching placebo once daily for 6 weeks, with a 4-week safety follow-up period. There may be a higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects and completing questionnaires.

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

NCT06696755IcalcaprantPlacebo for IcalcaprantBipolar I DisorderAbbvieBipolar Ii Disorder