Trial Outcomes & Findings for Countermeasures to Reduce Sensorimotor Impairment and Space Motion Sickness Resulting From Altered Gravity Levels (NCT NCT02136420)

Last Updated: 2018-01-08

Results Overview

Note that this applies to arms 1-4 only. Subjects sat on a chair on a moving platform on top of a centrifuge that created an artificial gravity environment. Subjects were repeatedly roll tilted to angles between 11 and 19 degrees, and then reported their perceived tilt angle using a subjective visual vertical task. They did this while experiencing centripetal acceleration equivalent to Earth gravity (1 Gz), and then hypogravity (0.5 Gz). We hypothesized that, after entering hypogravity, subjects would tend to underestimate their tilt angle. We calculated the percent change in their perception of tilt between 1 Gz and 0.5 Gz.

Recruitment status

COMPLETED

Study phase

PHASE4

Target enrollment

30 participants

Primary outcome timeframe

1 session

Results posted on

2018-01-08

Participant Flow

Participant milestones

Participant milestones
Measure	Tilt Perception, Training, Placebo placebo	Manual Control, Training, Placebo placebo	Perceptual Thresholds,Drug Then Placebo Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with promethazine then once with placebo, separated by \>4 days. This arm corresponds to results published in Diaz-Artiles et al 2017.	Perceptual Thresholds,Placebo Then Drug Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days. This arm corresponds to results published in Diaz-Artiles et al 2017.
Overall Study STARTED	10	10	5	5
Overall Study COMPLETED	9	10	5	5
Overall Study NOT COMPLETED	1	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Countermeasures to Reduce Sensorimotor Impairment and Space Motion Sickness Resulting From Altered Gravity Levels

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Tilt Perception, Training, Placebo n=10 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Manual Control, Training, Placebo n=10 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Perceptual Thresholds,Drug Then Placebo n=5 Participants Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with promethazine then once with placebo, separated by \>4 days. Promethazine: Subject receives promethazine Placebo: Placebo	Perceptual Thresholds,Placebo Then Drug n=5 Participants Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days. Promethazine: Subject receives promethazine Placebo: Placebo	Total n=30 Participants Total of all reporting groups
Age, Continuous	28.3 years STANDARD_DEVIATION 6.4 • n=93 Participants	28.0 years STANDARD_DEVIATION 6.3 • n=4 Participants	27.4 years STANDARD_DEVIATION 4.2 • n=27 Participants	24.8 years STANDARD_DEVIATION 2.9 • n=483 Participants	27.6 years STANDARD_DEVIATION 4.3 • n=36 Participants
Sex: Female, Male Female	4 Participants n=93 Participants	6 Participants n=4 Participants	1 Participants n=27 Participants	2 Participants n=483 Participants	13 Participants n=36 Participants
Sex: Female, Male Male	6 Participants n=93 Participants	4 Participants n=4 Participants	4 Participants n=27 Participants	3 Participants n=483 Participants	17 Participants n=36 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=93 Participants	1 Participants n=4 Participants	1 Participants n=27 Participants	1 Participants n=483 Participants	4 Participants n=36 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	9 Participants n=93 Participants	9 Participants n=4 Participants	4 Participants n=27 Participants	4 Participants n=483 Participants	26 Participants n=36 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants	0 Participants n=483 Participants	0 Participants n=36 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants	0 Participants n=483 Participants	0 Participants n=36 Participants
Race (NIH/OMB) Asian	3 Participants n=93 Participants	3 Participants n=4 Participants	0 Participants n=27 Participants	0 Participants n=483 Participants	6 Participants n=36 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants	0 Participants n=483 Participants	0 Participants n=36 Participants
Race (NIH/OMB) Black or African American	1 Participants n=93 Participants	0 Participants n=4 Participants	1 Participants n=27 Participants	0 Participants n=483 Participants	2 Participants n=36 Participants
Race (NIH/OMB) White	6 Participants n=93 Participants	7 Participants n=4 Participants	4 Participants n=27 Participants	3 Participants n=483 Participants	20 Participants n=36 Participants
Race (NIH/OMB) More than one race	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants	2 Participants n=483 Participants	2 Participants n=36 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants	0 Participants n=483 Participants	0 Participants n=36 Participants

PRIMARY outcome

Timeframe: 1 session

Outcome measures

Outcome measures
Measure	Training, Placebo n=9 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Perceptual Thresholds,Placebo Then Drug Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days.
Percent Change in Roll Tilt Perception After Exposure to Hypogravity	27.0 percentage change Interval 7.4 to 57.1	—

PRIMARY outcome

Timeframe: 2 sessions separated by at least four days; measurements made 2 hrs after ingestion of medication

This is a perceptual self-motion threshold that measures the precision of the vestibular system. It is analogous to an audiogram, but for motion. Subjects sat on a motorized platform which repeatedly provided them with small motions to the left or right. After each motion subjects report whether they perceived a motion to the left or right. Based on subject responses, a psychometric curve fit is performed that determines the threshold (the standard deviation of the underlying cumulative Gaussian). Yaw rotation means rotations about an axis that is perpendicular to gravity. This outcome measure applies only to arm 5 subjects.

Outcome measures

Outcome measures
Measure	Training, Placebo n=5 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Perceptual Thresholds,Placebo Then Drug n=5 Participants Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days.
Yaw Perceptual Motion Threshold Placebo	.83 deg per sec Standard Deviation .25	.92 deg per sec Standard Deviation .29
Yaw Perceptual Motion Threshold Promethazine	.86 deg per sec Standard Deviation .19	1.06 deg per sec Standard Deviation .26

PRIMARY outcome

Timeframe: 2 sessions separated by at least four days; measurements made 2 hrs after ingestion of medication

This is a perceptual self-motion threshold that measures the precision of the vestibular system. It is analogous to an audiogram, but for motion. Subjects sat on a motorized platform which repeatedly provided them with small motions to the left or right. After each motion subjects report whether they perceived a motion to the left or right. Based on subject responses, a psychometric curve fit is performed that determines the threshold (the standard deviation of the underlying cumulative Gaussian). Roll tilt means rotations about an axis that is Earth-horizontal. This outcome measure applies only to arm 5 subjects.

Outcome measures

Outcome measures
Measure	Training, Placebo n=5 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Perceptual Thresholds,Placebo Then Drug n=5 Participants Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days.
Roll Perceptual Motion Threshold Placebo	.27 deg per sec Standard Deviation .15	.32 deg per sec Standard Deviation .12
Roll Perceptual Motion Threshold Promethazine	.39 deg per sec Standard Deviation .20	.39 deg per sec Standard Deviation .13

PRIMARY outcome

Timeframe: 2 sessions separated by at least four days; measurements made 2 hrs after ingestion of medication

This is a perceptual self-motion threshold that measures the precision of the vestibular system. It is analogous to an audiogram, but for motion. Subjects sat on a motorized platform which repeatedly provided them with small motions to the left or right. After each motion subjects report whether they perceived a motion to the left or right. Based on subject responses, a psychometric curve fit is performed that determines the threshold (the standard deviation of the underlying cumulative Gaussian). Interaural translation refers to translations in the horizontal plane to the subject's left or right. This outcome measure applies only to arm 5 subjects.

Outcome measures

Outcome measures
Measure	Training, Placebo n=5 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Perceptual Thresholds,Placebo Then Drug n=5 Participants Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days.
Interaural Perceptual Motion Threshold Placebo	.57 cm per sec Standard Deviation .17	.78 cm per sec Standard Deviation .23
Interaural Perceptual Motion Threshold Promethazine	.77 cm per sec Standard Deviation .39	.80 cm per sec Standard Deviation .16

PRIMARY outcome

Timeframe: 1 session

Note that this applies to arms 6-9 only. Subjects sat on a chair on a moving platform on top of a centrifuge that created an artificial gravity environment. Subjects completed a manual control task in which their charge was randomly perturbed in roll tilt, and they used a joystick to attempt to keep themselves aligned with upright, while in the dark. They did this while experiencing centripetal acceleration equivalent to Earth gravity (1 Gz), and then hypogravity (0.5 Gz). We calculated their performance by calculating the standard deviation of chair position across time, with a smaller number indicating better performance. Then we calculated the percent change in their performance between 1 Gz and 0.5 Gz.

Outcome measures

Outcome measures
Measure	Training, Placebo n=10 Participants placebo Hyper gravity training: Subject receives hypergravity training before testing Placebo: Placebo	Perceptual Thresholds,Placebo Then Drug Subjects undergo perceptual motion threshold tests to determine the smallest motion they can reliably sense for yaw rotation, interaural translation and roll tilt. Each subject is tested twice, once with placebo then once with promethazine, separated by \>4 days.
Percent Change in Manual Control Performance After Exposure to Hypogravity	75.4 percentage change Standard Deviation 48.8	—

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Faisal Karmali

Massachusetts Eye and Ear Infirmary

Phone: 617-573-5593

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place