A randomized double blind placebo controlled study to evaluate the modulation of cognitive functions in Parkinson's subjects by sildenafil

ISRCTN	ISRCTN18044132
DOI	https://doi.org/10.1186/ISRCTN18044132
Secondary identifying numbers	A1481189

Submission date: 30/08/2005
Registration date: 26/09/2005
Last edited: 23/05/2016

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Nervous System Diseases

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Contact information

Dr David Burn
Scientific

Regional Neurosciences Centre
Newcastle General Hospital
Westgate Road
Newcastle
NE46BE
United Kingdom

Phone	+44 (0)1912563425
Email	d.j.burn@ncl.ac.uk

Study information

Study design	Randomised controlled trial
Primary study design	Interventional
Secondary study design	Randomised controlled trial
Study setting(s)	Not specified
Study type	Treatment
Scientific title	A randomized double blind placebo controlled study to evaluate the modulation of cognitive functions in Parkinson's subjects by sildenafil
Study acronym	SCOPE
Study objectives	That 48 weeks of sildenafil therapy will stabilize or slow down the progression of cognitive impairment in Parkinson's disease subjects with mild cognitive impairment when compared with untreated Parkinson's disease controls. The study will also assess the effects of sildenafil upon motor state and olfaction in Parkinson's disease since these parameters may also be improved by sildenafil.
Ethics approval(s)	Not provided at time of registration
Health condition(s) or problem(s) studied	Parkinson's disease (PD)
Intervention	Sildenafil dosing in the treatment group will start at 50 mg once daily for 4 weeks. Dosing is then increased to 100 mg daily for a further 44 weeks. The control group will receive matching placebo teatment for 48 weeks.
Intervention type	Drug
Pharmaceutical study type(s)
Phase	Not Specified
Drug / device / biological / vaccine name(s)	Sildenafil
Primary outcome measure	1. To test if 48 weeks of sildenafil therapy will result in improved cognitive functions in Parkinson's disease subjects as measured by the paired association learning (PAL) test 2. To test if 48 weeks of sildenafil therapy will result in improved olfaction in Parkinson's disease subjects as measured by the UPSIT test
Secondary outcome measures	To test if 48 weeks of sildenafil therapy will result in improved motor and cognitive function in Parkinson's disease subjects as measured by the Unified Parkinson's Disease Rating Scale (UPDRS), Dyskinesia Rating Scale, Spatial Working Memory Test and Reaction Time Test.
Overall study start date	14/12/2004
Completion date	30/09/2006

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	50 Years
Upper age limit	80 Years
Sex	Both
Target number of participants	100 subjects, 50 randomised to both sildenafil and placebo group
Key inclusion criteria	1. Male or female subjects (excluding women of child bearing potential) between the ages of 50 and 80 years, inclusive 2. Diagnosis of Parkinson's disease according to UK Parkinson's Disease Society Brain Bank Criteria 3. Diagnosis of Parkinson's disease >12 months 4. Mild cognitive impairment insufficient to fulfill Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for dementia, with MMSE score 18-27 5. University of Pennsylvania Smell Identification Test (UPSIT) test score of <30 6. Subjects must be willing and able to provide written informed consent
Key exclusion criteria	1. Subjects with evidence of severe or unstable concomitant medical illness 2. Known hypersensitivity to, or current use of sildenafil, or other PDE5 inhibitors 3. Clinically significant orthostatic hypotension (defined as disabling postural light-headedness or syncopal episodes associated with a fall in systolic blood pressure on standing of over 30 mmHg) 4. Patient taking anti-psychotic or cholinesterase inhibitor medication 5. Patient taking dopamine agonists 6. Major depressive disorder 7. Anosmia secondary to head injury/non-PD related cause 8. Exclusion of patients with Multiple Systems Atrophy 9. Exclusion of patients with colour-blindness 10. Subjects who were prescribed and/or are taking nitrates or nitric oxide donors in any form (oral, sub-lingual, tansdermal, inhalation,aerosols), alpha blockers and/or class IA or III anti-arrhythmic medication 11. Use of medication known or suspected to be potent or moderate inhibitors of cytochrome P4503A4 (excluding ketoconazole, itraconazole, cimetidine, ritonavir) 12. Subjects with congenital QT prolongation 13. Electrocardiogram (ECG) evidence of severe life-threatening rhythm or ischaemic disturbances including acute myocardial infarction (within last year), left bundle branch block, or ventricular tachycardia 14. QTcF prolongation >500 msecs 15. Sustained hypertension >170 mmHg systolic or >110 mmHg diastolic; sustained hypotension <90 mmHg systolic or <50 mmHg diastolic 16. History of regular alcohol abuse within 6 months of screening 17. Treatment with investigational drug within 30 days or 5 half-lives (whichever is longer) preceding the first dose of study medication
Date of first enrolment	14/12/2004
Date of final enrolment	30/09/2006

Locations

Countries of recruitment

England
United Kingdom

Study participating centre

Regional Neurosciences Centre

Newcastle
NE46BE
United Kingdom

Sponsor information

Pfizer Inc. (USA)
Industry

Groton Laboratories
Clinical Sciences Dept.
445 Eastern Point Road
Groton
CT06340
United States of America

"ROR"	https://ror.org/01xdqrp08

Funders

Funder type

Industry

Study is fully funded by Pfizer Inc. (USA)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan

Editorial Notes

23/05/2016: No publications found, verifying study status with principal investigator