A Study to Evaluate the Safety, Tolerability, Kinetics, Biodistribution and Repeatability of 11C-BMS-986196 After Intravenous (IV) Administration in Healthy Participants and After Repeat IV Administration in Participants With Multiple Sclerosis

Number of Participants With Adverse Events Based on Severity.

An adverse event (AE) is defined as any new untoward medical occurrence or worsening of a pre-existing medical condition in a clinical investigation participant administered study treatment that does not necessarily have a causal relationship with this treatment.

Time frame: From first visit up to 9 days post

Number of Participants With Clinically Significant Changes in Electrocardiograms.

Number of participants with clinically significant changes in electrocardiograms.

Time frame: From first visit up to 9 days post

Number of Participants With Clinically Significant Changes in Vital Signs.

Number of participants with clinically significant changes in vital signs.

Time frame: From first visit up to 9 days post

Number of Participants With Clinically Significant Changes in Laboratory Values.

Number of participants with clinically significant changes in laboratory values.

Time frame: From first visit up to 9 days post

Number of Participants With Clinically Significant Changes in Phsyical Examinations.

Number of participants with clinically significant changes in phsyical examinations.

Time frame: From first visit up to 9 days post

Number of Participants With Clinically Significant Changes in C-SSRS.

Number of participants with clinically significant changes in C-SSRS. Columbia-Suicide Severity Rating Scale (C-SSRS). The entire Columbia Suicide Severity Rating Scale (C-SSRS) will be administered, but the investigators will use its' Suicidal Ideation Intensity scale (0-25 score range summed from five items, with higher scores indicating more severe suicidal ideation) as the primary outcome. Data Not Collected

Time frame: Data Not Collected

Radiation Dosimetry Calculated From PET-CT Images in Healthy Participants

Measurement and assessment of radiation exposure and absorption of ionizing radiation in body tissue. The Organ Level Internal Dose Assessment (OLINDA) 2.0 software package (Hermes Medical Solutions) was used to estimate the organ and whole-body radiation absorbed doses. OLINDA uses Medical Internal Radiation Dose (MIRD) methodology (Stabin, Sparks, and Crowe 2005). The NURBs ICRP-89 adult male (73 kg) model was used to calculate the referent s-factors (Valentin and Streffer 2002). Tissue weighting factors defined in (ICRP Publication 103, 2007) were used to calculate the whole body effective dose (ED). All other MIRD assumptions about the homogeneity of source organ distribution were employed.

Time frame: 2 hours

Image Acquisition Window After Tracer Administration

Period of time required to collect the imaging data during a scan. Participants received a bolus intravenous administration of up to 370 MBq of 11CBMS- 986196. Immediately following the 11C-BMS-986196 administration, dynamic PET emission data were acquired for 90 minutes in a single bed position focused on the cranium. For PET acquisitions, a low dose CT scan was performed before administration of the radiotracer, to enable correction for attenuation of emitted radiation.

Time frame: 90 Mins

Percentage of Participants With Test Repeatablity Based on SUV.

Standardized uptake value (SUV) is Semi-quantitative measurement of tracer uptake in body tissue defined as ratio of radioactivity per unit volume of a region of interest to the radioactivity per unit volume of the whole body. Test-retest repeatability based on standardized uptake value (SUV) of CNS PET images in participants with MS: The test-retest repeatability will be based on a quantitative analysis of cranial PET images and will be evaluated for the Response-Evaluable 3 population. The test-retest repeatability (%), which is defined based upon the absolute value of the difference between test and retest values normalized by their mean: Test-Retest difference = RT-T Test-retest repeatability (%) = 100%-2×\|(RT-T)/(RT+T)\|×100% with T being the calculated value for the parameter measured at Visit 1 (test, T) and RT being the calculated value for the same parameter measured at Visit 2 (retest, RT).

Time frame: 2 hours

Percentage of Participants With Test Repeatablity Based on VT.

Volume of Distribution (VT) is the ratio of the radioligand concentration in a region of interest to the radioligand concentration in plasma at equilibrium. Test-retest repeatability based on VT of CNS PET images in participants with MS: The test-retest repeatability will be based on a quantitative analysis of cranial PET images and will be evaluated for the Response-Evaluable 3 population. The test-retest repeatability (%), which is defined based upon the absolute value of the difference between test and retest values normalized by their mean: Test-Retest difference = RT-T Test-retest repeatability (%) = 100%-2×\|(RT-T)/(RT+T)\|×100% with T being the calculated value for the parameter measured at Visit 1 (test, T) and RT being the calculated value for the same parameter measured at Visit 2 (retest, RT).

Time frame: 2 Hours

Percentage of Free Brain BTK Relative to Baseline

Percentage of free brain Burtons Tyrosine Kinase (BTK) relative to baseline

Time frame: Data Not Collected

Mean Standardized Uptake Value (SUV) in the Brain

Standardized uptake value (SUV) is Semi-quantitative measurement of tracer uptake in body tissue defined as ratio of radioactivity per unit volume of a region of interest to the radioactivity per unit volume of the whole body.

Time frame: On visits 1 (Day 1) and vist 2 (2hrs to 6 days after visit 1 tracer administration)

Mean Volume of Distribution (VT) in the Brain

Volume of Distribution (VT) is the ratio of the radioligand concentration in a region of interest to the radioligand concentration in plasma at equilibrium.

Time frame: On visits 1 (Day 1) and vist 2 (2hrs to 6 days after visit 1 tracer administration)