Adults 18 to 75, any sex, with Hepatic 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.
Maximum Observed Plasma Concentration (Cmax) of Plasma PF-07321332Primary· Day 1 at 0 (pre-dose for PF-07321332), 0.5, 1, 2, 3, 4, 6, 8, 10, and 12 hours, Day 2 at 24 and 36 hours, and Day 3 at 48 hours
Cmax was the maximum observed plasma concentration and was directly observed from data. Concentration values below the lower limit of quantification (LLQ) were set to zero. Geometric mean analysis was on the log scale. Zero values were not included in geometric mean and geometric coefficient of variation calculation. The geometric coefficient of variation was expressed in percentage.
Group
Value
95% CI
Normal Hepatic Function
1.886
± 20
Moderate Hepatic Impairment
1.923
± 48
Area Under the Plasma Concentration-Time Profile From Time Zero to Time of the Last Quantifiable Concentration (AUClast) of Plasma PF-07321332Primary· Day 1 at 0 (pre-dose for PF-07321332), 0.5, 1, 2, 3, 4, 6, 8, 10, and 12 hours, Day 2 at 24 and 36 hours, and Day 3 at 48 hours
AUClast was area under the plasma concentration time-curve from zero (pre-dose) to the last measured concentration. The geometric coefficient of variation was expressed in percentage.
Group
Value
95% CI
Normal Hepatic Function
14.97
± 36
Moderate Hepatic Impairment
14.86
± 43
Area Under the Plasma Concentration-Time Profile From Time Zero Extrapolated to Infinite Time (AUCinf) of Plasma PF-07321332Primary· Day 1 at 0 (pre-dose for PF-07321332), 0.5, 1, 2, 3, 4, 6, 8, 10, and 12 hours, Day 2 at 24 and 36 hours, and Day 3 at 48 hours
AUCinf was defined as area under the plasma concentration-time curve from time zero to infinity. The geometric coefficient of variation was expressed in percentage.
Group
Value
95% CI
Normal Hepatic Function
15.24
± 36
Moderate Hepatic Impairment
15.06
± 43
Number of Participants With an Treatment Emergent Adverse Event (TEAE)Secondary· Up to 2 months
An AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. Treatment-emergent adverse event (TEAE) means event between first dose of study treatment and up to 30 days after last dose that were absent before treatment or that worsened relative to pretreatment state. An SAE was an AE resulting in any of death; inpatient hospitalization; life-threatening experience; disability; congenital anomaly or deemed significant for any other reason.
Participants with adverse events (All Causalities)
Group
Value
95% CI
Normal Hepatic Function
3
Moderate Hepatic Impairment
4
Participants with adverse events (Treatment Related)
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
3
Number of Participants With Abnormal Electrocardiograms (ECGs)Secondary· Up to 2 months
ECG categorical summarization criteria: 1. PR interval (the interval between the start of the P wave and the start of the QRS complex, corresponding to the time between the onset of the atrial depolarization and onset of ventricular depolarization): a) greater than or equal to (\>=) 300 millisecond (msec), b) \>=25% increase when baseline is \> 200 msec or \>=50% increase when baseline is less than or equal to (\<=) 200 msec.
2\. QRS duration (time from ECG Q wave to the end of the S wave corresponding to ventricle depolarization): a) \>=140 msec, b) \>=50% increase from baseline.
3\. QTcF i
PR INTERVAL NOT OTHERWISE SPECIFIED (MSEC): Value ≥ 300
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
PR INTERVAL NOT OTHERWISE SPECIFIED (MSEC): %Change ≥ 25/50%
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
QRS INTERVAL NOT OTHERWISE SPECIFIED (MSEC): Value ≥ 140
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
QRS INTERVAL NOT OTHERWISE SPECIFIED (MSEC): %Change ≥ 50%
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
QT INTERVAL NOT OTHERWISE SPECIFIED (MSEC): Value > 500
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
QTC INTERVAL NOT OTHERWISE SPECIFIED (MSEC): 450 < Value ≤ 480
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
QTC INTERVAL NOT OTHERWISE SPECIFIED (MSEC): 480 < Value ≤ 500
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
QTC INTERVAL NOT OTHERWISE SPECIFIED (MSEC): Value > 500
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
Number of Participants With Abnormal Vital SignsSecondary· Up to 2 months
Criteria for vital signs abnormalities: increase or decrease from baseline in systolic blood pressure (SBP) \>=30 mm Hg and increase or decrease from baseline in diastolic blood pressure (DBP) \>=20 mm Hg; the value of SBP \<90 mm Hg; the value of DBP \<50 mm Hg; the value of pulse rate \<40 bpm or \>120 bpm.
SBP: Value <90mmHg
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
SBP: Change >= 30 mmHg increase from baseline
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
1
SBP: Change >= 30 mmHg decrease from baseline
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
DBP: Value <50 mmHg
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
DBP: Change >= 20 mmHg increase from baseline
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
DBP: Change >= 20 mmHg decrease from baseline
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
Pulse Rate: Value <40 bpm
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
Pulse Rate: Value >120 bpm
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
0
Number of Participants With Abnormal Laboratory Assessments (Without Regard to Baseline Abnormality)Secondary· Up to 2 months
Following laboratory parameters were assessed against pre-defined abnormality criteria: hematology; clinical chemistry; urinalysis.
HEMATOLOGY: Platelets (10^3/mm^3) <0.5× lower limit of normal (LLN)
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
1
HEMATOLOGY: Eosinophils (10^3/mm^3) >1.2× upper limit of normal (ULN)
Group
Value
95% CI
Normal Hepatic Function
1
Moderate Hepatic Impairment
2
HEMATOLOGY: Monocytes (10^3/mm^3) >1.2× ULN
Group
Value
95% CI
Normal Hepatic Function
0
Moderate Hepatic Impairment
1
CLINICAL CHEMISTRY: Direct Bilirubin (mg/dL) >1.5× ULN
Time frame: From the first dose of study treatment to the last dose of study treatment date +35 days (up to 2 months).
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
The study is to estimate the effect of hepatic impairment on the plasma PK of PF-07321332/ritonavir. Findings from this study will be used to develop dosing recommendations so that the dose and/or dosing interval may be adjusted appropriately in the presence of hepatic impairment.
Publications & conference data
7 peer-reviewed publications reference this trial (live from Europe PMC):
NCT05263895 — Relative Bioavailability Study of 4 Different Formulations of PF-07321332 Relative to the Commercial Tablet Formulation
· Phase 1
· completed
NCT05047601 — A Study of a Potential Oral Treatment to Prevent COVID-19 in Adults Who Are Exposed to Household Member(s) With a Confir
· Phase 2, PHASE3
· completed
NCT05011513 — Evaluation of Protease Inhibition for COVID-19 in Standard-Risk Patients (EPIC-SR).
· Phase 2, PHASE3
· terminated
NCT04960202 — EPIC-HR: Study of Oral PF-07321332/Ritonavir Compared With Placebo in Nonhospitalized High Risk Adults With COVID-19
· Phase 2, PHASE3
· completed
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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 Pfizer
Last refreshed: 6 September 2023
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/NCT05005312.