Food Effect Study to Evaluate the Effect of High-Fat Meal on the Relative Bioavailability of PF-07321332 Boosted With Ritonavir in Healthy Adult Participants

Area under the plasma concentration-time profile from time zero to the time of the last quantifiable concentration was determined by linear/log trapezoidal method and reported in this outcome measure.

AUCinf was calculated by AUClast + (Clast/kel). AUClast was the area under the plasma concentration-time profile from time zero to the time of the last quantifiable concentration (Clast). Clast was the predicted plasma concentration at the last quantifiable time point from the log-linear regression analysis and kel was the terminal phase rate constant calculated by a linear regression of the log-linear concentration-time curve.

Cmax was defined as maximum observed plasma concentration. It was observed directly from data.

Tmax was defined as the time to reach maximum observed plasma concentration of PF-07321332.

t1/2 was calculated by Loge(2)/kel. kel was the terminal phase rate constant calculated by a linear regression of the loglinear concentration-time curve.

Clearance of a drug is a measure of the rate at which a drug is metabolized or eliminated by normal biological processes. Clearance obtained after oral dose (apparent clearance) is influenced by the fraction of the dose absorbed. CL/F was calculated as dose/AUCinf.

Volume of distribution is defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired plasma concentration of a drug. Apparent volume of distribution after oral dose (Vz/F) is influenced by the fraction absorbed. Vz/F was calculated as dose/(AUCinf*kel). kel was the terminal phase rate constant calculated by a linear regression of the loglinear concentration-time curve.

An adverse event (AE) was any untoward medical occurrence in a participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An SAE was an AE which resulted in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent were events between first dose of study drug and up to maximum of 35 days after last dose that were absent before treatment or that worsened relative to pretreatment state.

Clinical laboratory abnormalities included following criteria: a) hematology evaluation included eosinophils/leukocytes greater than (>) 1.2* upper limit of normal (ULN), monocytes/leukocytes >1.2*ULN; b) clinical chemistry evaluation included urobilinogen greater than or equal to (>=) 1, fibrinogen >1.25*baseline; c) urinalysis evaluation included urine hemoglobin >=1.

Vital signs evaluations included supine blood pressure (BP) and pulse rate. The pre specified criteria for vital signs included systolic blood pressure (BP) minimum (min.) less than (<) 90 millimeter of mercury (mmHg); systolic BP change from baseline maximum (max.) decrease >= 30 mmHg, max. increase >=30 mmHg; diastolic BP min. <50mmHg; diastolic BP change from baseline max. decrease >=20, max. increase >=20; supine pulse rate min. <40 beats per minute (bpm) and max. >120 bpm.

A 12-lead ECG was obtained using an ECG machine that automatically calculated the heart rate and measured PR, QT, and QTc intervals and QRS complex. All scheduled ECGs were performed after the participant had rested quietly for at least 5 minutes in a supine position. The pre specified criteria for ECG values included absolute value of QTCF (Fridericia's correction formula): >=450 to less than or equal to (<=) 480 milliseconds, >480 to <=500 milliseconds, >500 milliseconds, increase from baseline >30 - <=60, increase from baseline >60. PR interval: >=300 milliseconds, increase from baseline: baseline >200 milliseconds and max. increase >=25% and baseline <=200 milliseconds and max. increase >=50%; QRS duration: >=140 milliseconds, increase from baseline >=50%.