Adults 18 to 60, any sex, with Healthy Participant. 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 Concentration (Cmax) of PF-07321332Primary· Days 1, 2, 3 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, and 48 hours postdose on Day 3) in Period 1; Days 1, 4, 5, 6 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, 48, and 72 hours postdose on Day 6) of Period 2.
The Cmax of PF-07321332 in the study was observed directly from data.
Area Under the Plasma Concentration-time Profile From Time Zero to Time Tau (τ), Where Tau=12-hour Dosing Interval(AUCtau) for PF-07321332Primary· Days 1, 2, 3 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, and 48 hours postdose on Day 3) in Period 1; Days 1, 4, 5, 6 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, 48, and 72 hours postdose on Day 6) of Period 2.
The AUCtau of PF-07321332 was determined by Linear/Log trapezoidal method.
Number of Participants With Treatment Emergent Adverse Events (TEAEs)Secondary· Screening up to Day 35
An Adverse event (AE) was any untoward medical occurrence in a participant. A serious AE was any untoward medical occurrence at any dose that resulted in death; was life-threatening; required hospitalization or prolongation of existing hospitalization; resulted in persistent or significant disability/incapacity; resulted in congenital anomaly/birth, was a suspected transmission via a Pfizer product of an infectious agent,pathogenic or non-pathogenic, was considered serious. The focus of AE summaries was on treatment-emergent AE (TEAE). An AE was considered TEAE if the event occurred during the
Number of Participants With Laboratory Abnormalities (Without Regard to Baseline Abnormality)Secondary· Screening up to Day 9 of Period 2 or Early termination/discontinuation.
Safety laboratory assessments included urinalysis, hematology, chemistry and other. All the safety laboratory samples were collected following at least a 4-hour fast.
Number of Participants With Clinically Significant 12-lead Electrocardiogram (ECG) FindingsSecondary· Screening up to Day 9 of Period 2 or Early termination/discontinuation.
Triplicate 12-lead ECG readings approximately 2 minutes apart were taken at each test. All ECG assessments were made after at least a 5-minute rest in a supine position and prior to any blood draws or vital sign measurements.
Change From Baseline in Vital Signs Data - Supine Systolic Blood PressureSecondary· Screening up to Day 9 of Period 2 or Early termination/discontinuation.
Vital signs(systolic and diastolic blood pressure, and pulse rate) were measured with participants after having a rest for at least 5 minutes in a supine position. Vital signs assessment were performed after collection of ECGs and prior to collection of blood draws if scheduled at the same time.
Change From Baseline in Vital Signs Data - Supine Diastolic Blood PressureSecondary· Screening up to Day 9 of Period 2 or Early termination/discontinuation.
Vital signs(systolic and diastolic blood pressure, and pulse rate) were measured with participants after having a rest for at least 5 minutes in a supine position. Vital signs assessment were performed after collection of ECGs and prior to collection of blood draws if scheduled at the same time.
Change From Baseline in Vital Signs Data - Supine Pulse RateSecondary· Screening up to Day 9 of Period 2 or Early termination/discontinuation.
Vital signs(systolic and diastolic blood pressure, and pulse rate) were measured with participants after having a rest for at least 5 minutes in a supine position. Vital signs assessment were performed after collection of ECGs and prior to collection of blood draws if scheduled at the same time.
Time for Cmax (Tmax) for PF-07321332Secondary· Days 1, 2, 3 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, and 48 hours postdose on Day 3) in Period 1; Days 1, 4, 5, 6 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, 48, and 72 hours postdose on Day 6) of Period 2
Terminal Half-life(t1/2) of PF-07321332Secondary· Days 1, 2, 3 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, and 48 hours postdose on Day 3) in Period 1; Days 1, 4, 5, 6 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, 48, and 72 hours postdose on Day 6) of Period 2
Terminal half-life was defined as the time measured for the plasma concentration of drug to decrease by one half.
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of the Last Quantifiable Concentration(AUClast) of PF-07321332Secondary· Days 1, 2, 3 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, and 48 hours postdose on Day 3) in Period 1; Days 1, 4, 5, 6 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, 48, and 72 hours postdose on Day 6) of Period 2.
AUClast of PF-07321332 was determined by Linear/Log trapezoidal method.
Apparent Clearance(CL/F) of PF-07321332Secondary· Days 1, 2, 3 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, and 48 hours postdose on Day 3) in Period 1; Days 1, 4, 5, 6 (pre-dose, 0.5, 1, 1.5, 2, 4, 6, 8, 12, 16, 24, 48, and 72 hours postdose on Day 6) of Period 2.
Time frame: From screening up to Day 35..
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
The purpose of this study is to estimate the effect of a strong inhibitor of CYP3A4 (itraconazole) on the pharmacokinetics (PK) of PF-07321332/ritonavir in healthy participants.
Publications & conference data
8 peer-reviewed publications reference this trial (live from Europe PMC):
NCT05339334 — A Study to Learn About the Study Medicine PF-07321332 and Ritonavir in Adult Healthy Chinese Participants.
· Phase 1
· completed
NCT05263921 — Relative Bioavailability Study of PF-07321332/Ritonavir Oral Powder Relative to the Commercial Tablets in Healthy Partic
· Phase 1
· completed
NCT05263895 — Relative Bioavailability Study of 4 Different Formulations of PF-07321332 Relative to the Commercial Tablet Formulation
· Phase 1
· completed
NCT05129475 — Food Effect Study to Evaluate the Effect of High-Fat Meal on the Relative Bioavailability of PF-07321332 Boosted With Ri
· Phase 1
· completed
NCT04962230 — Drug-Drug Interaction Study Assessing Effect of Carbamazepine on PF-07321332 Boosted With Ritonavir
· Phase 1
· completed
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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 Pfizer
Last refreshed: 13 July 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/NCT04962022.