Trial Outcomes & Findings for The Effects of Prazosin on Dopamine in Healthy Humans: A PET Pilot Study (NCT NCT01999530)

NCT ID: NCT01999530

Last Updated: 2019-05-30

Results Overview

Binding potential (an estimate of the ratio of Bmax/kd) was measured by positron emission tomography to determine if taking prazosin alters the amount of tracer bound to receptors. A negative change in binding potential means a decrease in binding potential and a positive change in binding potential represents an increase. Bmax is the total density of receptors. kd is the affinity of a drug for the target

• Recruitment status: COMPLETED
• Study phase: PHASE1
• Target enrollment: 20 participants
• Primary outcome timeframe: 3 weeks after taking prazosin
• Results posted on: 2019-05-30

Participant Flow

Participant milestones

Measure	Prazosin Hydrochloride Gradual upward titration to 15mg/day (or highest dose tolerated) for approximately three weeks. Prazosin Hydrochloride: Gradual upward titration to 15mg/day for approximately three weeks.
Overall Study STARTED	20
Overall Study COMPLETED	7
Overall Study NOT COMPLETED	13

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The Effects of Prazosin on Dopamine in Healthy Humans: A PET Pilot Study

Baseline characteristics by cohort

Measure	Prazosin Hydrochloride n=7 Participants Gradual upward titration to 15mg/day (or highest dose tolerated) for approximately three weeks. Prazosin Hydrochloride: Gradual upward titration to 15mg/day for approximately three weeks.
Age, Categorical <=18 years	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	7 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants
Sex: Female, Male Female	0 Participants n=5 Participants
Sex: Female, Male Male	7 Participants n=5 Participants
Race/Ethnicity, Customized Asian	1 participants n=5 Participants
Race/Ethnicity, Customized Caucasian	3 participants n=5 Participants
Race/Ethnicity, Customized Hispanic	2 participants n=5 Participants
Race/Ethnicity, Customized Mixed	1 participants n=5 Participants
Region of Enrollment Canada	7 participants n=5 Participants

PRIMARY outcome

Timeframe: 3 weeks after taking prazosin

Binding potential (an estimate of the ratio of Bmax/kd) was measured by positron emission tomography to determine if taking prazosin alters the amount of tracer bound to receptors. A negative change in binding potential means a decrease in binding potential and a positive change in binding potential represents an increase. Bmax is the total density of receptors. kd is the affinity of a drug for the target

Outcome measures

Measure	Prazosin Hydrochloride n=7 Participants Gradual upward titration to 15mg/day (or highest dose tolerated) for approximately three weeks. Prazosin Hydrochloride: Gradual upward titration to 15mg/day for approximately three weeks.
Changes in [11C]-(+)-PHNO Binding (Measured as Binding Potential) in Dorsal Caudate (DC)	2.1 binding potential Interval 1.4 to 2.8

Adverse Events

Prazosin Hydrochloride

Serious events: 0 serious events

Other events: 6 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	Prazosin Hydrochloride n=20 participants at risk Gradual upward titration to 15mg/day (or highest dose tolerated) for approximately three weeks. Prazosin Hydrochloride: Gradual upward titration to 15mg/day for approximately three weeks.
Gastrointestinal disorders Nausea	30.0% 6/20

Additional Information

Bernard Le Foll

Centre for Addiction and Mental Health

Phone: 416-535-8501

Email: bernard.lefoll@camh.ca

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place