MedPath

Trial of Ondansetron as a Parkinson's HAllucinations Treatment

Phase 2
Active, not recruiting
Conditions
Dementia With Lewy Bodies
Parkinson's Hallucinations
Interventions
Registration Number
NCT04167813
Lead Sponsor
University College, London
Brief Summary

TOPHAT (Trial of Ondansetron as a Parkinson's HAllucinations Treatment) is a double blind, individually randomized, placebo-controlled, parallel group, flexible dose trial of ondansetron (8-24mg/day) as a treatment for Parkinson's hallucinations, with a 12-week primary outcome and follow-up to 24 weeks.

Detailed Description

This study investigates whether ondansetron, a drug used to treat post-operative sickness, has a meaningful treatment effect on Parkinson's hallucinations, and whether the drug is safe and cost effective for use in the NHS. We will compare ondansetron to placebo (a tablet that looks identical but contains no drug) over 12 weeks treatment, with follow up (once treatment ends) for a further 12 weeks. Assessments of symptoms will be carried out during treatment (after 6 and 12 weeks), and once treatment ends (18, 24 weeks), to measure hallucinations, delusions (false beliefs), Parkinson's symptoms (tremor, anxiety, sleep disturbance), memory, quality of life, possible side-effects such as constipation and headache, and the proportion of people who drop out due to side effects, or require additional treatment for their hallucinations. Blood drug concentration (measured after 6 and 12 weeks) will provide information on how quickly the drug is cleared from the body, and how this relates to treatment effects and side-effects, to guide future prescribing in people with Parkinson's. Based on knowledge of the average hallucinations scores in previous Parkinson's treatment studies, 306 people will be needed for the study to detect a meaningful treatment effect. The study will run for 4 years and involves a series of linked stages: (1) Trial set up across 20-30 UK centres; (2) Recruitment over 2 years; (3) Completion of follow up; and analysis, publication and dissemination of results.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
168
Inclusion Criteria
  1. Adults aged over 18 years.

  2. Meet MDS criteria for Parkinson's disease or revised criteria for DLB.

  3. Score of 3 or more on the SAPS-H visual hallucinations item, indicating the presence of visual hallucinations at least weekly in the previous month.

  4. Score of 3 or more on SAPS-H global rating, indicating moderate symptom severity.

  5. Score of 4 or more on CGI-S, indicating moderate symptom severity.

  6. On a stable dose of anti-Parkinson's medication, cholinesterase inhibitor or memantine for at least 28 days.

  7. Capacity to give informed consent or, if lacking, legal representative able to give consent.

  8. Pre-menopausal women, and men whose partners are of child bearing potential will agree to use effective contraception. 9) If treated with an antipsychotic drug at the time of enrolment, can still participate, provided the drug is stopped the day before trial medication is commenced.

Exclusion Criteria
  1. Bradycardia (<50 bpm) (rescreen if reversible).

  2. Congenital long QTc syndrome or presence of clinically significant prolongation of QTc (>460 ms for men or >470 ms for women) on ECG screening.

  3. Severe hepatic failure (bilirubin >50 micromole/L)

  4. Prescribed apomorphine (if apomorphine is discontinued, rescreen once stable on an alternative anti-Parkinson's treatment).

  5. Prescribed tropisetron, granisetron, dolasetron.

  6. History of hypersensitivity to ondansetron and its excipients (or those of placebo) or drugs listed in 5).

  7. Participation in another Clinical Trial of an Investigational Medicinal Product (IMP) in the previous 28 days.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Matched placeboOndansetron 8mg or matched placebo tabletsParticipants randomised to the placebo treatment arm will take matched placebo, administered as tablets.
Active TreatmentOndansetron 8mg or matched placebo tabletsParticipants randomised to the active treatment arm will take 8-24mg/day of ondansetron.
Primary Outcome Measures
NameTimeMethod
Hallucinations12 weeks

Scale for Assessment of Positive Symptoms-Hallucinations (0-35 points, higher scores indicate greater severity of hallucinations

Secondary Outcome Measures
NameTimeMethod
Global illness severity2, 4, 6, 12, 18, 24 weeks

Clinical Global Impression of Severity Scale (1-7, higher scores indicate greater severity)

Safety and tolerability2, 4, 6, 12, 18, 24 weeks

Number of Participants With Treatment-Related Adverse Events

Hallucinations6, 12 weeks

University of Miami Parkinson's disease Hallucinations Questionnaire (0-15, where higher scores indicate greater symptom severity)

Non-motor symptoms2,4,6,12,18,24 weeks

Non-motor symptoms scale (0-120, higher scores indicate greater severity

Delusions2, 4, 6, 12, 18, 24 weeks

Scale for Assessment of Positive Symptoms-Delusions (0-65 points, higher scores indicate greater symptom severity

Health related quality of life6, 12, 18, 24 weeks

EQ-5D-5L

Cost effectiveness2, 4, 6, 12, 18, 24 weeks

Health and social service utilisation

Pharmacokinetics, plasma concentrations of the study drug6, 12 weeks

Measured using a validated HPLC/MS assay

Feasibility and Acceptability of Video Consultationbaseline, 6 and 12 weeks

The feasibility of video consultation will be measured at baseline, 6 and 12 weeks by the proportion of participants who were able to successfully attend on at least one occasion, the proportion who successfully attended all three assessments, and a Satisfaction questionnaire that allows both quantitative and qualitative information to be collected.

Cognition12 weeks

Standardised Mini-Mental State Examination (0-30, higher scores indicate better performance)

Trial Locations

Locations (23)

Dorset

🇬🇧

Poole, United Kingdom

Salford

🇬🇧

Salford, United Kingdom

Grampian

🇬🇧

Aberdeen, United Kingdom

Betsi Cadwaladr

🇬🇧

Bangor, United Kingdom

Pennine

🇬🇧

Bury, United Kingdom

Addenbrookes

🇬🇧

Cambridge, United Kingdom

Dartford

🇬🇧

Dartford, United Kingdom

Tayside

🇬🇧

Dundee, United Kingdom

Barking

🇬🇧

London, United Kingdom

Glasgow

🇬🇧

Glasgow, United Kingdom

Bart's Health

🇬🇧

London, United Kingdom

Imperial College NHS

🇬🇧

London, United Kingdom

Luton & Dunstable

🇬🇧

London, United Kingdom

Northumbria

🇬🇧

North Shields, United Kingdom

Cornwall

🇬🇧

Redruth, United Kingdom

Sherwood Forest

🇬🇧

Sutton In Ashfield, United Kingdom

Newcstle

🇬🇧

Newcastle, United Kingdom

Lewisham

🇬🇧

London, United Kingdom

UCLH NHS foundation trust

🇬🇧

London, United Kingdom

Anuerin Bevan

🇬🇧

Newport, United Kingdom

Oxford

🇬🇧

Oxford, United Kingdom

North West Anglia

🇬🇧

Peterborough, United Kingdom

North Midlands

🇬🇧

Stoke, United Kingdom

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