Adults 18 to 85, any sex, with Alzheimer's Disease or Amnestic Mild Cognitive Impairment. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Number of Participants With Adverse Events (AEs)Primary· Part 1: Up to 5 weeks; Part 2: up to 16 weeks
The number of participants experiencing an adverse event (AE) was monitored. An AE is any unfavorable and unintended medical occurrence, symptom, or disease witnessed in a participant, regardless of whether or not a causal relationship with the study treatment can be demonstrated. Further, any worsening of a preexisting condition that is temporally associated with the use of the study treatment is also considered an AE.
Group
Value
95% CI
Part 1, Healthy Young Participants
1
Part 2, Healthy Elderly Participants
3
Part 2, AD and Amnestic MCI Elderly Participants
2
Number of Participants Who Discontinued Study Due to an AEPrimary· Part 1: Up to 5 weeks; Part 2: up to 16 weeks
The number of participants discontinuing study due to an AE was monitored.
Group
Value
95% CI
Part 1, Healthy Young Participants
0
Part 2, Healthy Elderly Participants
0
Part 2, AD and Amnestic MCI Elderly Participants
0
Effective Dose of [18F]MK-6240Primary· Up to approximately 5 hours following [18F]MK-6240 administration
Mean effective dose (ED) of \[18F\]MK-6240 was calculated from whole-body (WB) PET scans of healthy young participants included in Part 1 of study. ED, reported as microsieverts (µSv) / megabecquerel (MBq), is a measure of WB radiation exposure risk that accounts for differences in individual organ exposure and organ susceptibility to ionizing radiation. Following \[18F\]MK-6240 PET tracer administration, organ-specific time-activity curves (TACs) and radioactivity residence times were utilized to calculate exposure risk for individual organs. These values calculated for individual organs were
Group
Value
95% CI
Part 1, Healthy Young Participants
29.4
± 0.6
Organ Effective Dose of [18F]MK-6240Primary· Up to approximately 5 hours following [18F]MK-6240 administration
Mean organ ED of \[18F\]MK-6240 was calculated from WB PET scans of healthy young participants included in Part 1 of study. Organ ED, reported as micrograys (µGy) / MBq, is a measure of organ-specific radiation exposure risk. Following \[18F\]MK-6240 PET tracer administration, organ-specific TACs and radioactivity residence times were utilized to calculate organ ED for specific organs of the body.
Adrenals
Group
Value
95% CI
Part 1, Healthy Young Participants
12.7
± 1.0
Brain
Group
Value
95% CI
Part 1, Healthy Young Participants
8.8
± 0.4
Breasts
Group
Value
95% CI
Part 1, Healthy Young Participants
5.8
± 0.9
Gallbladder Wall
Group
Value
95% CI
Part 1, Healthy Young Participants
202.0
± 111.0
Lower Large Intestine Wall
Group
Value
95% CI
Part 1, Healthy Young Participants
46.4
± 5.5
Small Intestine
Group
Value
95% CI
Part 1, Healthy Young Participants
116.0
± 13.3
Stomach Wall
Group
Value
95% CI
Part 1, Healthy Young Participants
16.9
± 3.7
Upper Large Intestine Wall
Group
Value
95% CI
Part 1, Healthy Young Participants
128.0
± 15.7
Standardized Uptake Value Ratio (SUVR) of [18F]MK-6240 in Brain Regions of InterestPrimary· From 60 to 90 minutes following [18F]MK-6240 administration
As a surrogate of regional \[18F\[MK-6240 tracer distribution volume (VT), mean standardized uptake value ratios (SUVRs), were calculated for specific brain regions of interest (ROIs) in healthy elderly as well as AD/MCI elderly participants in Part 2 of the study. Calculated using calibrated PET scan images from each participant, SUVR is the relative ratio of pixel intensities at a specific brain ROI compared to a reference region (RR; cerebellar cortex, for this study). For an individual participant, the average SUVR for each brain ROI is calculated starting at 60 minutes and ending at 90 mi
Frontal Lobe
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.95
± 0.07
Part 2, AD and Amnestic MCI Elderly Participants
1.22
± 0.47
Temporal Lobe
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.98
± 0.07
Part 2, AD and Amnestic MCI Elderly Participants
1.64
± 0.72
Parietal Lobe
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.95
± 0.06
Part 2, AD and Amnestic MCI Elderly Participants
1.42
± 0.80
Occipital Lobe
Group
Value
95% CI
Part 2, Healthy Elderly Participants
1.01
± 0.06
Part 2, AD and Amnestic MCI Elderly Participants
1.61
± 0.92
Insula and Cingulate Cortex
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.93
± 0.07
Part 2, AD and Amnestic MCI Elderly Participants
1.22
± 0.42
Hippocampus
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.93
± 0.10
Part 2, AD and Amnestic MCI Elderly Participants
1.37
± 0.25
Amygdala
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.84
± 0.11
Part 2, AD and Amnestic MCI Elderly Participants
1.67
± 0.40
Parahippocampal and Ambient Gyri
Group
Value
95% CI
Part 2, Healthy Elderly Participants
0.96
± 0.11
Part 2, AD and Amnestic MCI Elderly Participants
1.71
± 0.39
Intra-subject Test-Retest (T-RT) Variability of Standardized Uptake Value Ratio (SUVR) in Brain Regions of InterestPrimary· Up to 16 weeks following initial dose of [18F]MK-6240
For each AD/MCI participant receiving 2 doses of MK-6240, the SUVR (60-90 min) during initial dose (SUVR\_1) was compared to the SUVR (60-90 min) during the second dose (SUVR\_2) to determine the percent test-retest (T-RT) variability of the SUVR (60-90 min) for each brain ROI.
T-RT variability = (absolute value (SUVR\_1 - SUVR\_2) / average SUVR) \* 100. If T-RT variability = 0, indicates no variability between SUVR\_1 and SUVR\_2.
Frontal Lobe
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
7
Temporal Lobe
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
12
Parietal Lobe
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
7
Occipital Lobe
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
9
Insula and Cingulate Cortex
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
4
Hippocampus
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
6
Amygdala
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
5
Parahippocampal and Ambient Gyri
Group
Value
95% CI
Part 2, AD and Amnestic MCI Elderly Participants
6
Adverse events — posted to ClinicalTrials.gov
Time frame: Part 1: up to 5 weeks Part 2: up to 16 weeks.
Reporting threshold: 0%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
This 2-part, open-label study was designed to investigate the safety, tolerability, and efficacy of \[18F\]MK-6240, a Positron Emission Tomography (PET) imaging agent, for the quantification of neurofibrillary tangle (NFT) deposition in the brain. Brain NFT deposition is a pathologic finding in Alzheimer's Disease (AD), with brain NFT density shown to correlate with the severity of cognitive impairment in AD. The objectives of the study include performing the following with respect to \[18F\]MK-6240 administered as a PET imaging agent: 1) assess safety and tolerability; 2) determine radiation safety profile; 3) determine optimal imaging protocol parameters for quantification of brain NFTs in AD; 4) compare tracer binding in brain PET scans from participants with AD, participants with amnestic mild cognitive impairment (MCI) and healthy elderly participants; and 5) evaluate intra-subject test-retest (T-RT) variability of tracer uptake in brain regions of interest.
Publications & conference data
3 peer-reviewed publications reference this trial (live from Europe PMC):
NCT07457138 — Lombard Cohort of Brain Health Services
· recruiting
NCT07234942 — A Study to Investigate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of RO7812653 in Participants Wit
· Phase 1
· recruiting
NCT07479914 — Art of Memory for Cognitive Enhancement in the Monza Brain Health Service
· NA
· active not recruiting
NCT07214727 — A Study to Evaluate ALN-5288 in Patients With Alzheimer's Disease
· Phase 1
· recruiting
NCT07105709 — Open-label Extension Study in Participants With Early Alzheimer's Disease
· Phase 2
· recruiting
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Publications: Europe PMC API search by NCT ID, retrieved 9 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Merck Sharp & Dohme LLC
Last refreshed: 18 September 2018
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT02562989.