A Phase 1 interventional study of atirmociclib (PF-07220060) in Healthy Volunteer, sponsored by Pfizer. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-21.
Sponsored by Pfizer · Phase 1, Interventional, and Treatment
The purpose of this clinical trial is to learn about the dose proportionality on the PK of the study medicine (called atirmociclib) when administered in the various doses range under the fed condition in healthy participants.
This study is seeking participants who are:
All participants (72 total) in this study will receive atirmociclib at Dose (A), Dose (B), Dose (C), and Dose (D) oral dose in 1 of the 12 treatment sequences among 6 cohorts under fed conditions.
Atirmociclib will be given by mouth at the study research unit once single dose about 30 minutes after a moderate fat standard calorie meal.
Dose proportionality will be evaluated on the pharmacokinetics (PK), safety and tolerability of atirmociclib at Doses (A), (B), (C), and (D) oral dose under the fed condition.
Including the 28 days of screening window and the 35 days safety follow-up period, the total study duration for each participant can be up to 71 days, containing 2 periods (6 days for each period), minimum 7-day interval between two periods, and follow-up period 28 to 35 days from administration of the final dose of study intervention. During this time, they will undergo safety laboratory and serial blood PK samplings up to 120 hours after administration of atirmociclib to determine plasma concentrations of atirmociclib. Participants will be discharged from the research unit on Period 2 Day 6 following completion of all assessments.
Pfizer is the lead sponsor of 3,244 studies on the registry; 139 are open to participants now.
Of its 582 completed or terminated interventional studies of FDA-regulated products, 381 (65%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion:
In Period 1 Day 1, participants from Sequence AB and BA will receive Dose A and Dose B atirmociclib higher drug load IR MST tablet, respectively. In Period 2 Day 1, the participants from two sequences in the same cohort will shuffle the treatment.
Drug: atirmociclib (PF-07220060)
In Period 1 Day 1, participants from Sequence CD and DC will receive Dose C and Dose D atirmociclib higher drug load IR MST tablets, respectively. In Period 2 Day 1, the participants from two sequences in the same cohort will shuffle the treatment.
Drug: atirmociclib (PF-07220060)
In Period 1 Day 1, participants from Sequence AC and CA will receive Dose A and Dose C atirmociclib higher drug load IR MST tablet, respectively. In Period 2 Day 1, the participants from two sequences in the same cohort will shuffle the treatment.
Drug: atirmociclib (PF-07220060)
In Period 1 Day 1, participants from Sequence AD and DA will receive Dose A and Dose D atirmociclib higher drug load IR MST tablet, respectively. In Period 2 Day 1, the participants from two sequences in the same cohort will shuffle the treatment.
Drug: atirmociclib (PF-07220060)
In Period 1 Day 1, participants from Sequence BC and CB will receive Dose B and Dose C atirmociclib higher drug load IR MST tablets, respectively. In Period 2 Day 1, the participants from two sequences in the same cohort will shuffle the treatment.
Drug: atirmociclib (PF-07220060)
In Period 1 Day 1, participants from Sequence BD and DB will receive Dose B and Dose D atirmociclib higher drug load IR MST tablets, respectively. In Period 2 Day 1, the participants from two sequences in the same cohort will shuffle the treatment.
Drug: atirmociclib (PF-07220060)
Open-label, two-period, cross-over study to evaluate dose proportionality of atirmociclib (PF-07220060) pharmacokinetics when administered under fed condition to healthy participants
Area Under the Curve From Time Zero to Extrapolated Infinite Time (AUCinf)
Dose-normalized plasma AUCinf and Cmax of atirmociclib for each cohort (AUClast if AUCinf cannot be estimated)
Time frame: 1 hour prior to atirmociclib dosing, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 8, 12, 16, 24, 36, 48, 72, 96 and 120 hours post-dose
Maximum Observed Plasma Concentration (Cmax)
Time frame: 1 hour prior to atirmociclib dosing, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 8, 12, 16, 24, 36, 48, 72, 96 and 120 hours post-dose
Number of Participants With Adverse Events (AEs) by Seriousness and Relationship to Treatment
Time frame: Period 1: Days 1-6; minimum 7-day interval between two doses; Period 2: Day 1-35
Number of Participants With Laboratory Abnormalities
Time frame: Period 1: Days 1-6; minimum 7-day interval between two doses; Period 2: Day 1-35
Number of Participants With Abnormalities in Physical Examination
Time frame: Period 1: Days 1-6; minimum 7-day interval between two doses; Period 2: Day 1-35
Number of Participants With Clinically Significant Change in Electrocardiogram (ECG) Findings
Time frame: Period 1: Days 1-6; minimum 7-day interval between two doses; Period 2: Day 1-35
Number of Participants With Concomitant Medications
Time frame: Period 1: Days 1-6; minimum 7-day interval between two doses; Period 2: Day 1-35
Plan to share: No — Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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