A Study to Evaluate the Efficacy and Safety of Daridorexant in Participants With Insomnia Disorder

A Randomized, Double-blind, Multi-center, Placebo-controlled, Parallel, Phase III Study to Evaluate the Efficacy and Safety of ACT-541468 (Daridorexant) in Adult and Elderly Subjects With Insomnia Disorder

The purpose of this phase 3 study is to evaluate the efficacy and safety of Daridorexant compared to in participants with insomnia disorder.

Study Overview

• Status: Completed
• Conditions: Insomnia Disorder
• Intervention / Treatment: Drug: Daridorexant; Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 164
• Phase: Phase 3

Contacts and Locations

Study Locations

• South Korea
  • Busan, South Korea, 47392
    • Inje University Busan Paik Hospital
  • Busan, South Korea, 50612
    • Pusan National University Yangsan Hospital
  • Cheonan, South Korea, 31151
    • Soonchunhyang University Cheonan Hospital
  • Daegu, South Korea, 42601
    • Keimyung University Dongsan Medical Center
  • Daejeon, South Korea, 35015
    • Chungnam National University Hospital
  • Gwangju, South Korea, 61469
    • Chonnam National University Hospital
  • Ilsan, South Korea, 10380
    • Inje University Ilsan Paik Hospital
  • Incheon, South Korea, 21565
    • Gachon University Gil Medical Center
  • Incheon, South Korea, 22711
    • Catholic Kwandong University International St. Mary's Hospital
  • Seongnam-si, South Korea, 13620
    • Seoul National University Bundang Hospital
  • Seoul, South Korea, 03080
    • Seoul National University Hospital
  • Seoul, South Korea, 05505
    • Asan Medical Center
  • Seoul, South Korea, 05278
    • Kyung Hee University Hospital at Gangdong
  • Seoul, South Korea, 03722
    • Severance Hospital
  • Seoul, South Korea, 07804
    • Ewha Womans University Medical Center
  • Suwon, South Korea, 16247
    • The Catholic University of Korea, ST. Vincent's Hospital
  • Wŏnju, South Korea, 26426
    • Wonju Severance Christian Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Signed informed consent prior to any study-mandated procedure;
• Male or female aged ≥ 19 years;
• Insomnia disorder according to DSM-5 criteria;
• The predominant complaint is dissatisfaction with sleep quantity or quality, associated with one (or more) of the following symptoms:
• Difficulty initiating sleep.
• Difficulty maintaining sleep (characterized by frequent awakenings or problems returning to sleep after awakenings).
• Early-morning awakening with inability to return to sleep.
• Insomnia Severity Index score ≥ 15;
• Insufficient sleep quantity as collected subjectively in the sleep diary A. ≥ 30 min to fall asleep, and B. Wake time during sleep ≥ 30 min, and C. Subjective Total Sleep Time (sTST) ≤ 6.5 h

Exclusion Criteria:

• Body mass index (BMI) ≥ 40.0 kg/m2
• Documented medical history and/or comorbidity of sleep-related breathing disorder
• History of and/or concurrent sleep apnea or suspected sleep apnea
• Korean-Mini Mental State Examination-2 (K-MMSE-2) score < 25 in subjects ≥ 50 years;
• For female subjects: pregnant, lactating or childbearing potential who do not consent to true abstinence or use an effective method of contraception for required period
• Initiation of the cognitive behavior therapy (CBT) for treatment of insomnia disorder within 4 weeks prior to the Screening visit (Visit 1) or planned CBT during the study
• A history of moderate to severe hepatic impairment (eg, Child-Pugh Class B or C)
• Positive urine drug test or presence of alcohol in exhaled breath as detected by breathalyzer test.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo	Drug: Placebo; Placebo will be taken orally, once daily in the evening as indicated by investigator.
Experimental: Daridorexant	Drug: Daridorexant; Daridorexant will be taken orally, once daily in the evening as indicated by investigator.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective total sleep time(sTST)	Change from baseline to week 4 in subjective total sleep time (sTST) measured by eDairy	Week 4

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective latency to sleep onset (sLSO)	Change from baseline to week 4 in subjective latency to sleep onset (sLSO) measured by eDairy	Week 4
Subjective wake after sleep onset (WASO)	Change from baseline to week 4 in subjective wake after sleep onset (WASO) measured by eDairy	Week 4

Collaborators and Investigators

• Sponsor: Nxera Pharma Korea Co., Ltd.
• Investigators: Study Director: Clinical Development, Nxera Pharma Korea Co., Ltd., Nxera Pharma Korea Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): December 4, 2024
• Primary Completion (Actual): September 23, 2025
• Study Completion (Actual): October 21, 2025

Study Registration Dates

• First Submitted: June 11, 2025
• First Submitted That Met QC Criteria: June 11, 2025
• First Posted (Actual): June 19, 2025

Study Record Updates

• Last Update Posted (Actual): January 21, 2026
• Last Update Submitted That Met QC Criteria: January 19, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Mental Disorders; Sleep Wake Disorders; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Initiation and Maintenance Disorders; Substandard Drugs; Pharmaceutical Preparations; daridorexant
• Other Study ID Numbers: NPK-DAR-301

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No