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NCT05128058 · ClinicalTrials.gov registry record · Phase 1

A Target Occupancy Study With Ritlecitinib.

A Phase 1 study of Healthy, sponsored by Pfizer.

Completed
Registry status
Phase 1
Development phase
16
Enrollment target
1
Study location

NCT05128058: Completed Phase 1 study of Healthy, sponsored by Pfizer.

NCT05128058 is a Phase 1 study of Healthy that has completed, run by Pfizer. The registered enrollment target is 16 participants, below the 647-participant average among 1,090 other Healthy trials with a reported enrollment target (98% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT05128058, a Phase 1 study of Healthy, has completed, sponsored by Pfizer.

COMPLETED
Registry status
Phase 1
Development phase
16 participants
Enrollment target
1
Study location

Study Summary

This is a phase 1, open label, two-arm study to assess target occupancy and functional inhibition of JAK3 and TEC kinases by Ritlecitinib in healthy adult participants

Primary Outcome

Target occupancy for janus kinase 3 (JAK3) in peripheral blood mononuclear cells (PBMCs) by ritlecitinib was investigated in human blood by chemical probe-based enrichment and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis. % TO is calculated as \[(baseline value - value at specified time point)\*100/baseline value\], where baseline value in this formula is defined as the mean of the two pre-dose measurements at Hour -1 and Hour 0 on Day 1. Since (baseline value

Conditions Studied

Interventions

  • DRUG Ritlecitinib 50 mg
  • DRUG Ritlecitinib 200 mg

Study Locations (1)

Connecticut

  • Pfizer Clinical Research Unit - New Haven - New Haven

Trial Details

FieldValue
Enrollment Target 16 participants
Start Date 2021-10-22
Est. Completion 2022-01-14
Phase Phase 1
Pfizer

1,845 total trials

What the finished NCT05128058 record still lists

NCT05128058 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 16 participants, a relatively small participant target, below the 647-participant average among 1,090 other Healthy trials with a reported enrollment target (98% lower).

The record links to 1 condition, with Healthy appearing as the primary indexed condition, and to 2 interventions - of which Ritlecitinib 50 mg is the first listed.

NCT05128058 reports a single indexed study location in Connecticut.

Frequently Asked Questions

What is clinical trial NCT05128058 about?

NCT05128058 is a clinical study titled "A Target Occupancy Study With Ritlecitinib.". This is a phase 1, open label, two-arm study to assess target occupancy and functional inhibition of JAK3 and TEC kinases by Ritlecitinib in healthy adult participants

What is the current status of trial NCT05128058?

This trial is currently completed. It is a Phase 1 study. The enrollment target is 16 participants. The study started on 2021-10-22. Estimated completion is 2022-01-14.

What conditions does trial NCT05128058 study?

This clinical trial studies the following conditions: Healthy.

What interventions are being tested in trial NCT05128058?

The interventions under investigation include: Ritlecitinib 50 mg (DRUG), Ritlecitinib 200 mg (DRUG).

Who is sponsoring clinical trial NCT05128058?

This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT05128058 being conducted?

This trial has 1 study location across Connecticut. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Healthy

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT05128058's enrollment target sits among peer trials

16 936th of 1090 higher than 137 of 1,090 other Healthy trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Healthy trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT05128058, the US trial registry maintained by the National Library of Medicine. NCT05128058 (small enrollment · single site footprint · completed) retrieved and formatted by PlainTrial, see methodology.