A Study to Learn How Different Amounts of the Study Medicine Called PF-07999415 Are Tolerated and Act in the Body in Healthy Adults

Inclusion Criteria: * Male and female participants of non-childbearing potential aged 18 to 65 years, inclusive, at screening who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and cardiac monitoring. * Body Mass Index (BMI) of 18-33 kg/m2 and a total body weight \>50 kg (110 lb). Exclusion Criteria: * Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, dermatological, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing). * Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality or other conditions that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study. * Previous administration of an investigational product (drug or vaccine) within 30 days (or as determined by the local requirement) or 5 half-lives preceding the first dose of study intervention used in this study (whichever is longer). Participation in studies of other investigational products (drug or vaccine) at any time during participation in this study.