"Extended" (Alternate Day) Antipsychotic Dosing

NCT04478838 | Recruiting Phase 4

• 1 other identifier: 154-2018
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

The study wishes to examine whether "extended" antipsychotic treatment, in this case, antipsychotic treatment every other day, is as effective as daily treatment. It is also evaluating whether there may be differences in terms of side effects. Participants will be randomly assigned to either the treatment as usual group (i.e., taking antipsychotic daily) or the extended dosing group (i.e., taking antipsychotic one day on, one day off). That means, like flipping a coin, there is a 50/50 chance that participants will continue on daily dosing of your antipsychotic or have it switched to every other day dosing. This study will last for 1 year. Participants will be evaluated at the beginning and every two weeks during the first 6 months, with visits once every 4 weeks for the final 6 months. In total, participants will make 22 visits over 52 weeks to the investigator's office. The investigators hypothesize that with ED, there will be no change in symptom severity but improvement in the frequency and severity of side effects, wellbeing, and functioning.

Conditions

Drug Therapy; Schizophrenia and Related Disorders; Drug Administration Schedule; Antipsychotic Agents

Keywords

Extended Dosing; Alternate day dosing; Olanzapine; Risperidone; Paliperidone

Outcome Measures

Primary Outcomes (1)

• Clinical Deterioration using the "Brief Psychiatric Rating Scale - Expanded"

  Change in the Brief Psychiatric Rating Scale - total scores from baseline to 52 weeks. The score values for each item on the BPRS range from 1 to 7. The higher the score for each item the worse the outcome. The values for each item on the BPRS are scored as follows: 1- Not Present, 2 - Very Mild, 3- Mild, 4- Moderate, 5 - Moderately Severe, 6- Severe, 7- Very Severe.

  0 and 52 weeks

Secondary Outcomes (18)

• Exploratory Outcomes - Symptoms 1 using "The Clinical Global Impression - Schizophrenia Scale"

  0 and 52 weeks

• Exploratory Outcomes - Symptoms/Side Effects using "The Clinical Global Impression - Schizophrenia Scale"

  0 and 52 weeks

• Exploratory Outcomes - Symptoms 3 using the "Calgary Depression Scale for Schizophrenia"

  0 and 52 weeks

• Exploratory Outcomes - Symptoms 4 using the "Yale-Brown Obsessive-Compulsive Scale"

  0 and 52 weeks

• Exploratory Outcomes - Symptoms 5 using the "Hamilton Anxiety Scale"

  0 and 52 weeks

Study Arms (2)

Extended Dosing Group

EXPERIMENTAL

Participants taking olanzapine or risperidone or paliperidone will be switched to an alternate day dosing schedule.

Drug: Risperidone; Drug: Olanzapine; Drug: paliperidone

Treatment as Usual group

NO INTERVENTION

Participants will continue to take their olanzapine or risperidone or paliperidone following the same prescribed daily schedule.

Interventions

Risperidone DRUG

0.25 mg, 0.5 mg, 1 mg, 2 mg, 3 mg and 4 mg Tablets

Also known as: Risperdal

Extended Dosing Group

Olanzapine DRUG

2.5 mg, 5 mg, 7.5 mg, 10 mg, 15 mg, 20 mg Tablets

Also known as: Zyprexa, Apo-Olanzapine, Sandoz-Olanzapine

Extended Dosing Group

paliperidone DRUG

3 mg, 6 mg, 9 mg Tablets

Also known as: Invega

Extended Dosing Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• (i) A primary diagnosis of a Schizophrenia Spectrum or Other Psychotic Disorder as defined by the DSM-5 diagnosis and confirmed by the MINI (Version 7.0.2)
• (ii) age 18 or older
• (iii) female participants of childbearing potential must be using a reliable method of contraception and have a negative pregnancy test at the time of enrolment and must, in the investigator's opinion, practice a clinically accepted, reliable method of contraception during this study. Male participants must not father a baby during their time in the study
• (iv) ability to communicate in English
• (v) capacity to provide written, informed consent, as assessed using the MacCAT-CR at time of consent
• (vi) stabilized as outpatients with a single oral AP (risperidone or olanzapine or paliperidone\*) at the same dose for ≥3 months i. On a prescribed risperidone dose of between 1-6mg, or a prescribed olanzapine dose of between 5-20mg, or a prescribed paliperidone 3-12mg
• (vii) evidence of adherence with current AP treatment

You may not qualify if:

• (i) exposure to a depot AP within 1 year (i.e., no depot AP injection within the last year)
• (ii) Current diagnosis of substance use disorder according to DSM-5 criteria (verified through the MINI for Psychotic Disorders (Version 7.0.2) and a positive drug screen for street and /or prescription drugs not prescribed to the participant by treating physicians
• (iii) ECT within the last 3 months
• (iv) pregnancy or lactation
• (v) neurological condition (dementia including Alzheimer's disease, multiple sclerosis, epilepsy, stroke, or traumatic brain injury)
• (vi) allergy to the study drugs and their excipients
• (vii) allergy (e.g., galactosaemia) or severe intolerance to lactose
• (viii) negative urine drug screen result for Olanzapine or Risperidone or Paliperidone (if applicable)

Sponsors & Collaborators

• Centre for Addiction and Mental Health: lead

Study Sites (1)

Centre for Addiction and Mental Health

Toronto, Ontario, M5T 1R8, Canada

RECRUITING

MeSH Terms

Conditions

Schizophrenia

Interventions

Risperidone; Olanzapine; Paliperidone Palmitate

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Pyrimidinones; Pyrimidines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Benzodiazepines; Benzazepines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Isoxazoles; Azoles

Study Officials

• Gary J Remington, MD, PhD

  Centre for Addiction and Mental Health

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Carol Borlido

CONTACT

416-535-8501; carol.borlido@camh.ca

Gary Remington, MD, PhD

CONTACT

416-535-8501; gary.remington@camh.ca

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Senior Scientist

Study Record Dates

• First Submitted: July 16, 2020
• First Posted: July 21, 2020
• Study Start: June 6, 2022
• Primary Completion (Estimated): September 30, 2027
• Study Completion (Estimated): September 30, 2028
• Last Updated: April 13, 2026

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)