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Safety and Efficacy Study of Suvorexant in Participants With Primary Insomnia - Study A (MK-4305-028)

Merck Sharp & Dohme (MSD) logo

Merck Sharp & Dohme (MSD)

Status and phase

Completed
Phase 3

Conditions

Primary Insomnia

Treatments

Drug: Comparator: Placebo
Drug: Suvorexant Low Dose (LD)
Drug: Suvorexant High Dose (HD)

Study type

Interventional

Funder types

Industry

Identifiers

NCT01097616
4305-028
2010_520 (Other Identifier)

Details and patient eligibility

About

This is a multicenter study to test the hypothesis that suvorexant (MK-4305) is superior to placebo in improving insomnia as measured by change from baseline in: subjective total sleep time and time to sleep onset, wake time after persistent sleep onset, and latency to onset of persistent sleep. Participants who complete the initial 3-month Treatment (TRT) Phase may participate in an optional 3-month Extension (EXT) Phase.

Enrollment

1,023 patients

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

  • Must be ≥18 yrs old on the day of signing informed consent
  • Diagnosed with Primary Insomnia
  • Good physical and mental health
  • Participant ≥65 yrs old score at least 25 on the Mini Mental State Examination
  • A female participant who is of reproductive potential has a negative serum pregnancy test and agrees to use contraception
  • Reports difficulty with initiating and maintaining sleep during the 4 weeks prior to Visit 1 (accordingly to specific protocol criteria)
  • Reports spending 6.5 to 9 hours nightly in bed on at least 3 out of 7 nights prior to Visit 1
  • Regular bedtime is between 9 pm-1 am
  • Willing to refrain from napping while in study
  • Able to read, understand and complete questionnaires and all diaries
  • Willing to limit alcohol, caffeine, and nicotine consumption while in the study
  • For a portion of participants: Must be willing to stay overnight in a sleep laboratory and must be willing to stay in bed for at least 8 hours each night while at the sleep laboratory

Exclusion criteria

  • Female participant is pregnant and/or breastfeeding at Prestudy visit, or expecting to conceive while in study
  • History or diagnosis of another sleep disorder
  • Difficulty sleeping due to a medical condition
  • History of a neurological disorder
  • History of bipolar disorder, psychotic disorder, or posttraumatic stress disorder, or current psychiatric disorder that requires a prohibited medication
  • Ongoing depression
  • History of substance abuse or dependence
  • History or current evidence of a clinically significant cardiovascular disorder or clinically significant electrocardiogram (ECG) at Prestudy Visit
  • Taking certain prohibited medications
  • Consumption of the equivalent of >15 cigarettes a day
  • History of malignancy ≤5 years prior to signing informed consent, except for adequately treated basal cell or squamous cell skin cancer or in situ cervical cancer
  • Participant is considered morbidly obese
  • Previously randomized in another investigational study of suvorexant

Trial design

Primary purpose

Treatment

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Double Blind

1,023 participants in 3 patient groups, including a placebo group

Suvorexant HD
Experimental group
Description:
Drug
Treatment:
Drug: Suvorexant High Dose (HD)
Suvorexant LD
Experimental group
Description:
Drug
Treatment:
Drug: Suvorexant Low Dose (LD)
Placebo
Placebo Comparator group
Description:
Placebo Comparator
Treatment:
Drug: Comparator: Placebo

Trial contacts and locations

0

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Data sourced from clinicaltrials.gov

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