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 greater than 50 kg (greater than 110 lb) * Stable hepatic impairment that meets the criteria for Class A or B of the Child Pugh classification with no clinically significant change in disease status within the 28 days 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 hepatocellular process 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 active Stage 2 encephalopathy is allowed if, in the opinion of the investigator, the participant is able to provide informed consent.