A Study to Learn How the Body Processes the Study Medicine Called Osivelotor (PF-07940367) in People With Loss of Liver Function

Inclusion Criteria:

• Body mass index (BMI) of 16 to 40 kg/m2, inclusive; and a total body weight greaterthan 50 kg (greater than 110 lb)

• Stable hepatic impairment that meets the criteria for Class A or B of the Child Pughclassification with no clinically significant change in disease status within the 28days prior to the screening visit

• Stable concomitant medications for the management of individual participants'medical history

Exclusion Criteria:

• Any condition possibly affecting drug absorption (eg, prior bariatric surgery,gastrectomy, ileal resection, prior status portacaval shunt surgery);

• Hepatic carcinoma or hepatorenal syndrome or limited predicted life expectancy;

• A diagnosis of hepatic dysfunction secondary to any acute ongoing hepatocellularprocess that is documented by medical history, physical examination, liver biopsy,hepatic ultrasound, computerized tomography scan, or MRI;

• Presence of clinically active Stage 3 or 4 hepatic encephalopathy. Clinically activeStage 2 encephalopathy is allowed if, in the opinion of the investigator, theparticipant is able to provide informed consent.