Study to Estimate the Effects of Hepatic Impairment on the Pharmacokinetics (PK) of PF-07321332

A PHASE 1, NON-RANDOMIZED, OPEN-LABEL STUDY TO ASSESS THE PHARMACOKINETICS, SAFETY AND TOLERABILITY OF PF-07321332 BOOSTED WITH RITONAVIR IN ADULT PARTICIPANTS WITH MODERATE HEPATIC IMPAIRMENT AND HEALTHY PARTICIPANTS WITH NORMAL HEPATIC FUNCTION

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.

Inclusion Criteria:

• Male and female participants who are classically healthy having no clinically relevant abnormalities. No known or suspected hepatic impairment
• Stable hepatic impairment that meets the criteria for Class B of the Child-Pugh Classification

Exclusion Criteria:

• Any condition possibly affecting drug absorption (eg, prior bariatric surgery, gastrectomy, ileal resection).
• Participants who have been vaccinated with COVID-19 vaccines within the past week of dosing
• A positive urine drug test, for illicit drugs, at Screening
• History of sensitivity reactions to ritonavir or any of the formulation components of PF-07321332 or ritonavir.
• eGFR <60 mL/min/1.73m2 based on the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation
• Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) level ≥ upper limit of normal (ULN) (for healthy participants); AST or ALT > 5x ULN (for hepatic impairment participants)
• Albumin > ULN (for healthy participants);
• Prothrombin time > ULN (for healthy participants);
• Total bilirubin level ≥1.5 × ULN [NOTE: Participants with a history of Gilbert syndrome (and hence elevated total bilirubin) are eligible provided direct bilirubin level is ≤ ULN).