NCT04394845 is a Phase 1 clinical trial of [18F]GTP1 in Alzheimer Disease, sponsored by Genentech, Inc..

Who is sponsoring NCT04394845?

NCT04394845 is sponsored by Genentech, Inc..

What drugs are being tested in NCT04394845?

Interventions in NCT04394845: [18F]GTP1.

What condition does NCT04394845 study?

NCT04394845 studies Alzheimer Disease.

Is NCT04394845 still recruiting?

NCT04394845 is currently completed. Last updated 3 November 2021.

Are results published for NCT04394845?

Yes — primary outcome results have been posted to ClinicalTrials.gov. See the outcomes section above for details.

Last reviewed 2021-11-03 · How we verify

NCT04394845

Name: Drug Landscape Pharmaceutical Database
Creator: Drug Landscape
Published: 2026-01-01
License: https://creativecommons.org/licenses/by/4.0/

A Study of the Biodistribution and Safety of [18F]GTP1 in Healthy Japanese Participants

Completed Phase 1 Results posted Last updated 3 November 2021

What this trial tests

Phase 1 trial testing [18F]GTP1 in Alzheimer Disease in 6 participants. Completed in 9 October 2020.

Timeline

11 August 2020

Primary endpoint
9 October 2020

9 October 2020

Quick facts

Lead sponsor	Genentech, Inc.
Phase	Phase 1
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	diagnostic
Enrollment	6
Start date	11 August 2020
Primary completion	9 October 2020
Estimated completion	9 October 2020
Sites	1 location across United States

Drugs / interventions tested

[18F]GTP1 — full drug profile →

Conditions studied

Alzheimer Disease — all drugs for Alzheimer Disease →

Sponsor

Genentech, Inc. — full company profile →

Who can join

18 and older, any sex, with Alzheimer Disease. 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.

Total Source Organ Counts Based on Individualized Organ Volumes of Interest (VOIs) Primary · Day 1

Decay corrected \[18F\]GTP1 time-activity in the source organs acquired following bolus tracer injection and expressed as %Injected Dose (ID).

Mean collect time: 5.32767 minutes

Group	Value	95% CI
[18F]GTP1	0.33530	± 0.18795

Mean collect time: 16.38604 minutes

Group	Value	95% CI
[18F]GTP1	0.59398	± 0.11540

Mean collect time: 32.41194 minutes

Group	Value	95% CI
[18F]GTP1	2.13730	± 0.76985

Mean collect time: 53.21428 minutes

Group	Value	95% CI
[18F]GTP1	4.89330	± 1.41690

Mean collect time: 78.27645 minutes

Group	Value	95% CI
[18F]GTP1	9.38103	± 3.07024

Mean collect time: 97.78638 minutes

Group	Value	95% CI
[18F]GTP1	12.93725	± 4.91340

Mean collect time: 144.06733 minutes

Group	Value	95% CI
[18F]GTP1	20.76320	± 5.05449

Mean collect time: 187.27612 minutes

Group	Value	95% CI
[18F]GTP1	25.22968	± 6.09050

Source Organ Residence Time (Total Number of Disintegrations) Primary · Day 1

Source organ uptake and washout with calculation of total number of disintegrations (or residence time, or kinetic values) using the area under the time-activity curve divided by the injected dose of radiopharmaceutical

Brain

Group	Value	95% CI
[18F]GTP1 Female	0.0375	± 0.00295
[18F]GTP1 Male	0.0315	± 0.00717

Gallbladder Contents

Group	Value	95% CI
[18F]GTP1 Female	0.0254	± 0.038
[18F]GTP1 Male	0.0304	± 0.023

Gallbladder Contents with GB emptying model

Group	Value	95% CI
[18F]GTP1 Female	0.0102	± 0.012
[18F]GTP1 Male	0.0122	± 0.00637

LLI Cont.

Group	Value	95% CI
[18F]GTP1 Female	0.0416	± 0.00214
[18F]GTP1 Male	0.0396	± 0.00401

SI Cont.

Group	Value	95% CI
[18F]GTP1 Female	0.415	± 0.0219
[18F]GTP1 Male	0.395	± 0.0397

ULI Cont.

Group	Value	95% CI
[18F]GTP1 Female	0.228	± 0.0117
[18F]GTP1 Male	0.217	± 0.0219

Heart Wall

Group	Value	95% CI
[18F]GTP1 Female	0.0153	± 0.00326
[18F]GTP1 Male	0.019	± 0.00774

Kidneys

Group	Value	95% CI
[18F]GTP1 Female	0.046	± 0.0195
[18F]GTP1 Male	0.0448	± 0.0114

Mean Radiation Absorbed Dose Estimates in Target Organs and Whole Body Based on Standard Medical Internal Radiation Dose (MIRD) Methodology Primary · Day 1

Radiation absorbed dose estimates based on the Medical Internal Radiation Dose (MIRD) methodology utilizing urine data and International Commission on Radiological Protection (ICRP) gastrointestinal (GI) tract kinetics

Adrenals

Group	Value	95% CI
[18F]GTP1 Female	0.0164	± 0.00156
[18F]GTP1 Male	0.0123	± 0.000451

Brain

Group	Value	95% CI
[18F]GTP1 Female	0.00789	± 0.00075
[18F]GTP1 Male	0.00606	± 0.00132

Breasts

Group	Value	95% CI
[18F]GTP1 Female	0.00595	± 0.000974
[18F]GTP1 Male	0.00457	± 0.00044

Gallbladder Wall

Group	Value	95% CI
[18F]GTP1 Female	0.0756	± 0.0662
[18F]GTP1 Male	0.0713	± 0.0353

LLI Wall

Group	Value	95% CI
[18F]GTP1 Female	0.0447	± 0.00236
[18F]GTP1 Male	0.0376	± 0.00314

Small Intestine

Group	Value	95% CI
[18F]GTP1 Female	0.117	± 0.00513
[18F]GTP1 Male	0.0925	± 0.00864

Stomach Wall

Group	Value	95% CI
[18F]GTP1 Female	0.0141	± 0.000929
[18F]GTP1 Male	0.0106	± 0.000758

ULI Wall

Group	Value	95% CI
[18F]GTP1 Female	0.127	± 0.00513
[18F]GTP1 Male	0.105	± 0.00974

Percentage of Participants With Adverse Events Primary · Up to 5 days

An AE is the appearance or worsening of any undesirable sign, symptom, or medical condition, even if the event is not considered to be related to study drug. Study drug includes the investigational drug under evaluation during any phase of the study. Medical conditions/diseases present before starting study drug are only considered AEs if they worsen after starting study drug. Abnormal laboratory values or test results constitute AEs only if they induce clinical signs or symptoms, are considered clinically significant, or require therapy.

Group	Value	95% CI
[18F]GTP1	1

Adverse events — posted to ClinicalTrials.gov

Time frame: Baseline up to 5 days. Reporting threshold: 5%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

[18F]GTP1

Serious: 0/6 (0%)

Deaths: 0/6

Other adverse events (1 terms — click to expand)

Reaction	System	[18F]GTP1
Haematoma	Vascular disorders	—

Data from ClinicalTrials.gov NCT04394845 adverse events section.

Sponsor's own description

The purpose of this study is to evaluate the biodistribution, safety and tolerability of a single dose of \[18F\]GTP1 as a tau targeted radiopharmaceutical in healthy Japanese participants.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

Tauvid™: The First FDA-Approved PET Tracer for Imaging Tau Pathology in Alzheimer's Disease.
Jie CVML, Treyer V, Schibli R, Mu L. · · 2021 · cited 92× · PMID 33573211 · DOI 10.3390/ph14020110

Verify or expand the search:

Other trials of [18F]GTP1

Trials testing the same drug.

NCT04566003 — Evaluation Comparing Tau PET Radiotracers, [18F]GTP1 and [18F]PI-2620 or [18F]MK-6240 in Subjects With Normal Cognition · Phase 1 · completed
NCT03828747 — A Study of Semorinemab in Patients With Moderate Alzheimer's Disease · Phase 2 · completed
NCT03289143 — A Study to Evaluate the Efficacy and Safety of Semorinemab in Patients With Prodromal to Mild Alzheimer's Disease · Phase 2 · terminated
NCT02640092 — Longitudinal Evaluation of [18F]GTP1 as a PET Radioligand for Imaging Tau in the Brain of Participants With Alzheimer's · Phase 1 · completed

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Other Genentech, Inc. trials

Trials by the same sponsor.

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Verify against primary sources

ClinicalTrials.gov — authoritative US registry record
WHO ICTRP — international registry index
EU Clinical Trials Register
Sponsor press releases (Google)

Data sources for this page

Trial protocol + status: ClinicalTrials.gov NCT04394845 (US National Library of Medicine, public domain)
Publications: Europe PMC API search by NCT ID, retrieved 10 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 Genentech, Inc.
Last refreshed: 3 November 2021

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/NCT04394845.

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing