The purpose of this clinical trial is to learn if the study medicine (called PF-07976016) is safe and how it goes in and out of the body in healthy people. The study may also explore if PF-07976016 has the potential to interact with another medicine called midazolam. In addition, the study may explore how PF-07976016 goes into the body of people who have obesity.

Key Inclusion Criteria:

1. 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.
2. A total body weight >50 kg (110 lb).
3. Parts A, B and C only: BMI of 20-33 kg/m2.
4. Part D only: BMI of 30-40 kg/m2 and may have well controlled hyperlipidemia or hypertension.

Key Exclusion Criteria:

1. Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, skin or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).

2. Any condition possibly affecting drug absorption.

3. Previous administration with 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 their participation in this study.

4. Standard 12-lead ECG that demonstrates clinically relevant abnormalities that may affect participant safety or interpretation of study results.

5. Renal impairment as defined by an estimated glomerular filtration rate of <75 mL/min/1.73 m².

6. Participants with ANY of the following abnormalities in clinical laboratory tests at screening, as assessed by the study specific laboratory and confirmed by a single repeat test, if deemed necessary:

   • alanine aminotransferase, aspartate aminotransferase, or bilirubin ≥1.05 × upper limit of normal;
   • fasting plasma glucose > 126 mg/dL;
   • HbA1c ≥6.0% (Parts A,B and C); HbA1c ≥6.5% (Part D);
   • hematuria as defined by ≥1+ heme on urine dipstick;
   • albuminuria as defined by urine albumin/creatinine ratio >30 mg/g.

Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.

Parts A, B and D are double-blinded and sponsor-open while Part C is open-label.